82nd Annual Meeting of the American Thyroid Association MEETING ABSTRACTS & PROGRAM

1 Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom 2 Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada 3 Center for Human and Clinical Genetics, Leiden University Medical Center, Leiden, Netherlands 4 Department of Pediatric Endocrinology, Emma Children's Hospital, Academic Medical Center, Amsterdam, Netherlands 5 Department of Pediatrics, Leiden University Medical Center, Leiden, Netherlands 6 The Sanger Institute Mouse Genetics Project, Wellcome Trust Sanger Institute, Hinxton, United Kingdom 7 Division of Molecular Neuroendocrinology, National Institute for Medical Research, Mill Hill, United Kingdom 8 Neural Development Unit, UCL Institute of Child Health, London, United Kingdom 9 Department of Medical Sciences, Universita degli Studi di Milano, Milan, Italy 10 School of Medicine and Pharmacology, Freemantle Hospital Unit, The University of Western Australia, Crawley, WA, Australia 11 Department of Pediatrics, West Middlesex University Hospital, Ilesworth, United Kingdom 12 Department of Endocrinology and Metabolic Disorders, Leiden University Medical Center, Leiden, Netherlands 13 Developmental Endocrinology Research Group, Clinical and Molecular Genetics Unit, UCL Institute of Child Health and Great Ormond Street Hospital for Children, London, United Kingdom Oral 1 LOSS-OF-FUNCTION MUTATIONS IN IGSF1 CAUSE A NOVEL, X-LINKED SYNDROME OF CENTRAL HYPOTHYROIDISM AND TESTICULAR ENLARGEMENT

Disorders of Thyroid Function Thursday Oral Clinical 9:00 AM

Congenital central hypothyroidism occurs either as an isolated thyroid-stimulating hormone (TSH) deficiency or in conjunction with other pituitary hormone deficits. Undetected central hypothyroidism is associated with developmental delay in children and adverse cardiometabolic sequelae in adults. Hitherto, mutations in the thyrotropin-releasing hormone receptor (TRHR) or TSHβ subunit (TSHB) genes are the only known causes of isolated TSH deficiency.

Using whole-exome and candidate gene sequencing, we have studied 10 unrelated families with males exhibiting isolated TSH deficiency, testicular enlargement, and variably low serum prolactin levels.

We have identified nine distinct mutations in the X-linked immunoglobulin superfamily member 1 (IGSF1) gene in affected males. IGSF1 encodes a pituitary-enriched plasma membrane glycoprotein; disease-associated mutations block trafficking of IGSF1 from the endoplasmic reticulum to the membrane, consistent with the loss-of-protein function. We have also characterized IGSF1-deficient mice. Adult male IGSF1 null mice show decreased pituitary TSH content and circulating T4 levels, together with increased body weight and fat mass, recapitulating features of the human disorder. Decreased TRHR mRNA levels in pituitaries from null mice, together with reduced TSH bioactivity in patients with IGSF1 mutations, suggest that impaired TRH signaling may be the basis for hypothyroidism.

Collectively, our observations delineate a novel X-linked syndrome in which loss-of-function mutations in IGSF1 cause central hypothyroidism, testicular enlargement, and variable prolactin deficiency, and identify a previously unsuspected role for IGSF1 in hypothalamic–pituitary control of thyroid and testicular function.

1 Leibniz Institute for Age Research/Fritz Lipmann Institute, Jena, Germany 2 Internal Medicine, Erasmus Medical Center, Rotterdam, Netherlands 3 Center for Molecular Biomedicine, Friedrich-Schiler-University, Jena, Germany 4 Laboratory of Comparative Endocrinology, KU Leuven, Leuven, Belgium Oral 2 CONSEQUENCES OF BRAIN-SPECIFIC THYROID HORMONE DEPRIVATION IN MCT8/OATP1C1 DOUBLE KNOCKOUT MICE

Thyroid Hormone Metabolism & Regulation Thursday Oral Basic 9:15 AM

Inactivating mutations in the thyroid hormone (TH) transporter MCT8 cause a severe form of psychomotor retardation. In mice, Mct8 deficiency results in an impaired transport of T3, but not of T4 into the brain, and it is not associated with any neurological impairments. We speculated that in mice, TH uptake into the CNS is facilitated by Mct8 and by Oatp1c1, a T4-specific TH transporter localized at the blood–brain barrier.

To define the role of Mct8 and Oatp1c1 in brain TH transport, we generated Mct8/Oatp1c1 double knockout (dko) mice and analyzed them by determining T4 transport, brain TH content, deiodinase activities, and expression levels of TH-regulated gene products in wild type, the respective single and double mutant animals. Immunohistochemical stainings were performed to determine neuronal differentiation and myelination at different postnatal time-points. Animals were also subjected to extensive behavioral studies.

In contrast to Mct8 ko and Oatp1c1 ko mice, Mct8/Oatp1c1 dko mice exhibited a strongly diminished uptake of T4 into the CNS. Hence, brain T4 and T3 content was pronouncedly reduced, while type 2 deiodinase activities were found to be highly elevated. Determination of T3-regulated gene products indicated a severe hypothyroid state of the brain in the absence of both transporters. As a consequence, differentiation of inhibitory neurons in the cerebral cortex, as well as myelination, was strongly impaired. Finally, behavior tests revealed coordination and locomotor deficits in Mct8/Oatp1c1 dko mice.

Our data point to a critical function of Mct8 and Oatp1c1 in the transport of TH into the brain. Since Oatp1c1 is only weakly expressed in the human CNS, Mct8/Oatp1c1 dko mice may be considered as an animal model for human MCT8 deficiency.

1 Medicine, Mount Sinai School of Medicine, New York, NY 2 VA Medical Center, James J. Peters VA Medical Center, Bronx, NY 3 Department of Pediatrics, University of Cincinnati, Cincinnati, OH Oral 3 ROLE OF INTERFERON-ALPHA IN DEVELOPMENT OF AUTOIMMUNE THYROIDITIS: EPIGENETIC REGULATION OF KEY GENES

Disorders of Thyroid Function Thursday Oral Basic 9:30 AM

Autoimmune thyroid diseases (AITDs) result from interactions between genetic and environmental factors. Several AITD susceptibility loci have been identified through genome-wide association studies, but the causal variants remain undefined. Recent evidence suggests that epigenetic mechanisms modulate the complex interplay between genes and intra- and extracellular factors to trigger pathological autoimmune responses. Since cytokines are key mediators of tissue inflammation and infiltration, we tested the hypothesis that inflammatory cytokines promote thyroid cell dysfunction through epigenetic modifications of AITD genes. One prime cytokine in the etiology of AITD is interferon-alpha (IFNa), which has also been shown to precipitate AITD when used as therapeutic agent. We have previously shown that IFNa increases mRNA expression of major AITD susceptibility genes in both cell lines and a mouse model of IFNa thyroid expression.

We mapped modifications of histone patterns [histone H3 mono- and trimethylated at Lys-4 (H3K4me1 and H3K4me3)] induced by IFNa at these loci using ChIP-seq in human thyroid cells. ChIP-seq data were integrated with RNA-seq and bioinformatic analyses.

Integration of ChIP-seq and RNA-seq data showed that significantly upregulated pathways included genes characterized by H3K4me3 enrichment in the 5′-regions, demonstrating a correlation between H3K4me3 and pathway activation by IFNa. Most upregulated genes/pathways participate in innate immunity and host defense response. IFNa induced enrichment of H3K4me1 mostly in noncoding gene regions. We next used the potential of H3K4me1 to mark regulatory regions to identify functional AITD-associated single-nucleotide polymorphisms (SNPs). An AITD-associated SNPs, in thyroglobulin (TG) gene was marked by enrichment of H3K4me1. This same SNP was previously shown by us through bioinformatic analyses followed by ChIP, luciferase reporter, and siRNA assays to bind interferon regulatory factor-1 (IRF1) and to modulate TG promoter activity in an allele-dependent manner.

Our results demonstrate that an unbiased genome-wide epigenomic screening can pinpoint the disease-associated variants and identify novel genetic–epigenetic interactions.

1 Head and Neck Surgery, Memorial Sloan Kettering Cancer Center, New York, NY 2 Endocrinology, Memorial Sloan Kettering Cancer Center, New York, NY 3 Nuclear Medicine, Memorial Sloan Kettering Cancer Center, New York, NY Oral 4 THE RESULTS OF SELECTIVE USE OF RADIOACTIVE IODINE ON SURVIVAL AND RECURRENCE IN THE MANAGEMENT OF PAPILLARY THYROID CANCER BASED ON MSKCC RISK GROUP STRATIFICATION

Thyroid Cancer Thursday Oral Clinical 9:45 AM

The American Thyroid Association guidelines on the management of well-differentiated thyroid cancer (WDTC) recommend the routine use of RAI in all T3 or greater primary tumors, and selective use in patients with intrathyroidal disease <1 cm, or evidence of nodal metastases. The guidelines recognize that there are conflicting and inadequate data to make firm recommendations for most patients. The aim of this study was to analyze our experience of the selective use of radioactive iodine (RAI) in the management (WDTC).

Retrospective review of 1129 patients who underwent total thyroidectomy in Memorial Sloan Kettering Cancer Center between 1986 and 2005: the median age was 46 years (range 11–91 years) with a man-to-woman ratio of 1:2.8. All patients were managed with total thyroidectomy and had no evidence of macroscopic residual disease after surgery or distant metastases. Four hundred ninety were pT1/T2N0, 193 pT1/T2N1, and 444 were pT3/T4. All patients were assessed using the GAMES risk stratification method. Select patients within each group did not receive RAI. Details on recurrence and disease-specific survival were recorded by the Kaplan–Meier method and compared using the log-rank test.

With a median follow-up of 63 months (range 1–282 months), select patients with early primary disease (pT1/T2) and low-volume metastatic disease in the neck (pT1/T2 N1) who were managed without RAI had excellent outcomes. In the group with advanced local disease (pT3/T4), select patients with pT3N0 disease were safely managed without RAI. The 5-year DSS and RFS in the pT1/T2N0, pT1/T2N1, and pT3/T4 were 100% and 92%, 100% and 92%, and 98% and 87%, respectively.

Our results justify the selective use of RAI following initial surgical treatment using a risk group stratification method. The place of RAI in the management of PTC should not be a blanket treatment for all. Instead clinicians must make the decision on whether to recommend adjuvant RAI on a case-by-case basis using a multidisciplinary team experienced in the management of thyroid cancer.

1 University of Pennsylvania School of Medicine, Philadelphia, PA 2 Biostatistics, University of Washington, Seattle, WA 3 Medicine, Epidemiology and Health Services, University of Washington, Seattle, WA Oral 7 THE NATURAL HISTORY OF SUBCLINICAL HYPERTHYROIDISM IN THE ELDERLY: THE CARDIOVASCULAR HEALTH STUDY

Disorders of Thyroid Function Thursday Oral Clinical 2:10 PM

Subclinical hyperthyroidism affects 1–2% of individuals aged 65 and older, yet the degree to which it persists over time and its associated health risks in this population are unclear. We examined transitions in the thyroid status over a 2–3-year period and the risks of cardiovascular and total mortality in older individuals with subclinical hyperthyroidism.

In 5,009 US-community-dwelling men and women aged 65 and over who were enrolled in the Cardiovascular Health Study and not taking thyroid medications, serum TSH and free-T4 concentrations were measured in banked specimens at 1989–90, 1992–93, and 1996–97 visits. We identified 70 subjects with subclinical hyperthyroidism (TSH<0.45 mU/L with a normal free-T4 level) at their first TSH measurement and examined persistence, resolution, and progression of subclinical hyperthyroidism over 2–3 years. Cox proportional hazards models were used to determine the relationship between subclinical hyperthyroidism and cardiovascular and total mortality over ten years of follow-up, using 4194 euthyroid individuals (TSH 0.45–4.5 mU/L) as a reference group. All models were adjusted for age, sex, race, and initiation of thyroid medications.

Of the 70 individuals with subclinical hyperthyroidism, 60% were women, 24% were nonwhite, and mean age was 73.7 years. Among those with subclinical hyperthyroidism who obtained follow-up thyroid testing or were taking thyroid medication at follow-up (n=44), 43% persisted; 41% became euthyroid; 5% progressed to overt hyperthyroidism; and 11% initiated thyroid medication. There was no association between initial TSH and total or cardiovascular mortality (see Table).

Subclinical hyperthyroidism persists in nearly half of older individuals, with high rates of reversion to euthyroidism. Although numbers were small, subclinical hyperthyroidism was not associated with overall or cardiovascular mortality.

1 Endocrine Oncology Unit, Gustave Roussy Institute, Villejuif, France 2 Nuclear Medicine Unit, Bergonie Institute, Bordeaux, France Oral 9 IMPACT OF MOLECULAR TARGETED THERAPIES IN PATIENTS WITH BONE METASTASES OF DIFFERENTIATED THYROID CARCINOMA

Thyroid Cancer Thursday Oral Clinical 2:40 PM

Bone metastases (BM) are frequent in patients with differentiated thyroid cancer and may impair the quality of life. We aimed to study the frequency of bone progression in patients treated with tyrosine kinase inhibitors (TKI) because of progressive soft tissue disease of radioactive iodine refractory-differentiated thyroid cancer.

In this monocentric retrospective study, we reviewed patients with BM treated with TKI, from 2007 to 2012. BM were monitored by clinical exam, CT, or TEP-CT imaging every 3 months. Bone progression was defined by the occurrence of a skeletal event and/or the appearance of a new bone lesions and/or progression of known measurable bone lesions.

Thirty patients (19 men, mean age 57 years, 11 with papillary, 9 with follicular, and 10 with poorly differentiated thyroid cancer) were treated with vandetanib (n=12), sorafenib (n=19), sunitinib (n=8), or motesanib (n=2), with 4 patients receiving two successive TKIs and 3 patients receiving 3 successive TKIs. Response to TKI treatment at 3 months according to RECIST 1.0 was a partial response in 4 (10%) cases, stable disease in 24 (59%) cases, and progressive disease in 13 (31%) cases. Among the 28 nonprogressive patients under treatment, 19 (68%) had stable bone disease, and 9 (32%) had bone progression, including 2 with new bone lesions, 1 with a skeletal-related event, and 6 with progression of known bone lesions. Among the 13 patients with progressive disease during treatment, 7 (53%) had stable bone disease, and 6 (47%) had bone progression, including 2 with a skeletal-related event and 6 with progression of known bone lesions.

Evaluation of bone metastases of patients under TKI is essential, because 32% of the patients with nonprogressive soft tissue lesions can disclose bone progression during treatment.

1 Division of Endocrinology, Diabetes and Metabolism, University of Miami, Miller School of Medicine, Miami, FL 2 Laboratory of Endocrinology Neurobiology, Hungarian Academy of Sciences, Institute of Experimental Medicine, Budapest, Hungary 3 Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Tufts Medical Center, Boston, MA Oral 11 PITUITARY-SPECIFIC INACTIVATION OF TYPE II DEIODINASE (D2) REVEALS COORDINATION BETWEEN THE CONVERSION OF T4 TO T3 IN THYROTHROPHS AND IN TANYCYTES IN THE T4-MEDIATED TSH FEEDBACK MECHANISM

Thyroid Hormone Metabolism & Regulation Thursday Oral Basic 1:40 PM

The type 2 deiodinase (D2) catalyzes the conversion of T4 to T3 and thus plays a role in the T4-mediated TSH feedback mechanism. However, the role played by D2 in the different anatomical sites within the central nervous system has not been defined.

Here we used p-flox technology to develop two new mouse strains, the first lacking D2 activity in pituitary thyrotrophs (Pit-D2KO) and the second lacking D2 activity in astrocytes (Astro-D2KO).

Neither mouse strain exhibited gross phenotypic abnormalities, with development and reproductive function largely preserved. In both new strains, the analysis of body weight, brain, epididymal fat, liver, and muscle weight, showed no difference when compared to the respective Cre-expressing controls. The Pit-D2KO mouse exhibited normal serum T3 and was systemically euthyroid, but had an elevated serum T4 due to a disruption in the T4-mediated TSH feedback mechanism. The elevated serum T4 decreased paraventricular TRH mRNA, defining a critical role for hypothalamic D2 in the T4-mediated TRH feedback mechanism. Furthermore, these animals also exhibited lower pituitary TSHa mRNA levels, whereas TSHb mRNA remained unaffected. The reduction in TRH expression and its implication for TSH glycosylation (prolonged half-life and decreased biological activity) explain why Pit-D2KO mice had an elevated serum TSH that only minimally affected the thyroid gland. That this critical role played by hypothalamic D2 resides in the tanycytes is defined by the analysis of the Astro-D2KO mouse, in which there was almost complete D2 inactivation in the brain, except for the hypothalamic tanycytes that preserve thyroid economy.

These data indicate the existence of close coordination between T4-to-T3 conversion in thyrotrophs and tanycytes. The disruption of the D2-mediated T4 signaling in the pituitary is compensated for by an increase in D2-mediated T4 signaling in the hypothalamus, which preserves thyroidal activity and T3 serum levels.

1 Department of Molecular Virology, Immunology, and Medical Genetics, The Ohio State University, Columbus, OH 2 Center for Biostatistics, The Ohio State University, Columbus, OH 3 Department of Pediatrics, Uniformed Services University of the Health Sciences, Bethesda, MD 4 National Hormone and Peptide Program, Harbor-UCLA Medical Center, Torrance, CA 5 Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 6 Division of Endocrinology, Diabetes and Metabolism, The Ohio State University, Columbus, OH Oral 12 MICE HARBORING THYROID-SPECIFIC DELETION OF PRKAR1A AND PTEN IN COMBINATION DEVELOP METASTATIC FOLLICULAR THYROID CARCINOMA

Thyroid Cancer Thursday Oral Basic 1:55 PM

While both follicular and papillary thyroid cancer (FTC and PTC, respectively) generally respond well to treatment, it is known that FTC has a greater risk of progression, including distant metastases, and these patients have few treatment options. Thus, it remains of utmost importance to identify molecular changes that lead to aggressive and metastatic FTC in hopes of identifying novel drug targets for therapy. Our lab has demonstrated that thyroid-specific ablation of the Carney Complex gene, PRKAR1A, leads to hyperthyroidism and FTC in mice (R1a-TpoKO mice). However, while these animals develop FTC, none developed distant metastases.

To better study the molecular basis for aggressive FTC formation, we crossed the R1a-TpoKO mice with animals carrying a conditional null allele of the Cowden Syndrome gene Pten, which has been shown to promote tumorigenesis in many tissues, including the thyroid.

These Double R1a and Pten KO (DRP-TpoKO) mice show highly elevated thyroid hormone levels and, on average, weigh less than their wild-type littermates beginning at 2 months of age, indicating functional hyperthyroidism. Ultrasound imaging of these mice has shown that the thyroids of these animals are enlarged as early as 2 months of age and continue to grow rapidly resulting in morbidity due to tracheal compression. By 6 months of age, 100% of DRP-TpoKO mice develop FTC. Additionally, ∼30% of these animals develop well-differentiated lung metastases, suggesting that two genetic hits are required for the development of metastatic FTC. Histologically, these tumors resemble aggressive cases of human FTC, and interestingly, ∼60% of these cancers show areas of squamous metaplasia, a feature that has been described in a small percentage of human FTC, but the significance of which is unknown. Microarray studies indicate alteration of multiple developmental and differentiation pathways in these cancers, suggesting that the molecular changes driving cancer formation also lead to squamous metaplasia.

These mice represent an important and reliable new tool for the study of molecular mechanisms that drive the formation of distant metastases in FTC and may lead directly to the development and testing of novel FTC therapies.

1 College of Pharmacy, Univ Minnesota, Duluth, MN 2 Biochemistry, Univ Minnesota, Duluth, MN 3 Pediatrics, Univ Minnesota, Minneapolis, MN Oral 14 FETAL AND NEONATAL IRON DEFICIENCY EXACERBATES THE EFFECT OF PTU-INDUCED TH INSUFFICIENCY ON NEONATAL THYROIDAL STATUS AND BRAIN TH-RESPONSIVE GENE EXPRESSION

Disorders of Thyroid Function Thursday Oral Basic 2:25 PM

Iron (Fe) and iodine/thyroid hormone (TH) deficiencies during development lead to similar molecular, cellular, and behavioral abnormalities that persist into adulthood, and often coexist in individuals living in developing countries. We recently demonstrated that fetal/neonatal Fe deficiency results in a mild perturbation of the thyroid axis, suggesting that TH insufficiency contributes to the neurodevelopmental abnormalities associated with Fe deficiency. We hypothesized that combining Fe deficiency with an additional mild thyroidal perturbation during development would result in a more severe insult to the neonatal thyroid axis and to TH-responsive gene expression in the neonatal brain.

To test this hypothesis, pregnant Sprague-Dawley rats were assigned to one of seven different treatment groups early in gestation: control, Fe-deficient (FeD), mild TH-deficient (1 ppm PTU), moderate TH-deficient (3-ppm PTU), severe TH-deficient (10-ppm PTU), FeD/1-ppm PTU, or FeD/3-ppm PTU. At postnatal day 15 or 16 (P15 or P16), thyroidal status and brain TH-responsive gene expression were assessed.

Iron deficiency or 1-ppm PTU treatment alone had mild effects on neonatal thyroidal status, reducing serum total T4 concentrations by 64% and 74%, respectively, without significantly altering serum total T3 concentrations. Neither treatment alone significantly altered cortical or hippocampal T3 concentrations. Interestingly, however, FeD combined with 1-ppm PTU treatment produced a more severe effect on neonatal thyroidal status reducing serum total T4 by 95%, and lowering hippocampal and cerebral cortical T3 concentrations by 24% and 31%, respectively, compared to controls. Combined FeD/1-ppm PTU also resulted in a more severe effect on brain TH-responsive gene expression than either treatment alone, significantly altering the hippocampal and cortical mRNA levels for Parvalbumin, Type 2 deiodinase, and Hairless.

These data suggest that combining mild thyroidal insults during pregnancy and early-neonatal life results in significant perturbation of the thyroid axis and impairment of TH-regulated brain gene expression.

1 Division of Endocrinology, Department of Medicine, Mount Sinai Medical Center, New York, NY 2 Department of Medicine, James J. Peters VA Medical Center, Bronx, NY 3 Department of Medicine, Mount Sinai Medical Center, New York, NY 4 Institute for Personalized Medicine, Mount Sinai Medical Center, New York, NY Oral 15 CHRONIC HEPATITIS C VIRUS AND INTERFERON-INDUCED THYROIDITIS: IDENTIFICATION OF ASSOCIATED GENES AND EVIDENCE FOR SHARED SUSCEPTIBILITY WITH THYROID AUTOIMMUNITY

Autoimmunity Thursday Oral Translational 2:40 PM

Autoimmune thyroid disease (AITD) has become increasingly recognized as a complication of interferon-alpha (IFNα) therapy in patients with chronic hepatitis C virus (HCV). Interferon-induced thyroiditis (IIT) can manifest as clinical thyroiditis in ∼15% of HCV patients receiving IFNα and subclinical thyroiditis (i.e., thyroid antibody positive) in up to 40% of patients, possibly resulting in discontinuation of IFNα. Data regarding susceptibility genes in IIT are sparse and inconclusive. We aimed to identify genetic markers that can potentially recognize patients at risk of IIT before initiating IFNα treatment and thereby prevent the complications associated with thyroid disease.

To identify susceptibility genes in IIT, we used the customized infinium immunochip covering 9021 genes to genotype a cohort of 245 patients with chronic HCV infection and compared their genotypes to those of a set of 851 healthy Caucasian controls. Due to an ethnically mixed patient population, we performed principal component analysis to ensure appropriately matched controls and to avoid population stratification. Association analyses were performed on 2 groups: 1) all IIT patients compared to chronic hepatitis C patients who did not develop thyroiditis and 2) Caucasian IIT patients compared to healthy Caucasian controls.

Of the 245 patients included in our analyses, we confirmed presence of IIT in 53 individuals and absence of disease in 192 individuals after at least 12 weeks of IFNα therapy. Based on p-value<0.005 and on gene function, we selected up to 25 candidate genes distinguishing IIT cases from both chronic HCV and healthy Caucasian controls. Strong genetic association with IIT was found with significant overlap noted between the 2 groups analyzed (see Table), and several genes known to be associated with AITD, including HLA, TSHR, and CTLA-4, were also identified.

Immunochip analyses identified candidate genes predisposing to IIT with evidence for shared susceptibility with thyroid autoimmunity. These represent markers that may identify individuals at risk of thyroiditis induced by IFNα therapy.

1 Department of Endocrinology Diabetes and Metabolism, Temple University School of Medicine, Philadelphia, PA 2 Internal Medicine, Mercy Catholic Medical Center, Philadelphia, PA Poster 38 A RARE CASE OF TETRASOMY-13 OFFSPRING IN A WOMAN WITH HYPERTHYROIDISM UNDETECTED DURING PREGNANCY

Autoimmunity Thursday Poster Basic

Several studies have reported that women with autoimmune thyroid disease (AITD) are at increased risk of birth defects in the offspring. We present a case of tetrasomy-13 offspring born to a mother with undiagnosed, symptomatic hyperthyroidism during pregnancy.

A 20-year-old African American woman with no medical history presented to our hospital 5 months postpartum with florid symptoms of thyrotoxicosis with an increase in the neck size with pain, compressive symptoms, palpitations, diaphoresis, fatigue, heat intolerance, dry itchy eyes, and diplopia for almost 1 year. On exam, she was anxious looking with proptosis, lid lag, tremors, tachycardia, and diffusely enlarged thyroid gland with a bruit. Biochemical workup revealed a suppressed TSH-0.01 mIU/mL with an elevated FT4-5.4 ng/dL and FT3-2840 pg/dL with positive TPO antibody >1000 IU/mL. She was treated with antithyroid medications, beta-blockers, and lugols iodine for a clinical diagnosis of Graves' disease. Her history dates back to the time when she was pregnant and noticed to have increase in the neck size and bulging eyes. However, due to poor antenatal follow-up and manageable symptoms, she was never seen for her thyroid problem. At 34 weeks of gestation, she delivered a malformed baby with multiple midline hemangiomas, dysmorphic facial features, and failure to thrive. Genetic testing revealed terminal triplication of the long arm of chromosome 13, tetrasomy13q32.2qter. Despite several attempts for resuscitation, the baby expired within 3 months.

We believe that the birth defect in the baby of this young woman was associated with her uncontrolled Graves' disease during pregnancy. Autoimmune thyroid disease is a rare cause of congenital fetal anomalies, especially trisomy, and there have been only few studies and one case report. However, a causal association has not been established.

Currently, there is no consensus on universal screening for thyroid disease in pregnancy. Given the increased risk of adverse fetal and maternal outcomes, we encourage that every woman should be screened for thyroid disease in the perinatal period.

1 Medicine, Kuma Hospital, Kobe, Japan; ²Pharmacovigilance, Chugai Pharmaceutical Co., Ltd., Tokyo, Japan Poster 39 ANALYSES OF 733 REPORTED CASES WITH AGRANULOCYTOSIS

Autoimmunity Thursday Poster Clinical

Agranulocytosis (AGR) is rare, but one of the most serious, complications caused by antithyroid drugs (ATD). It is considered that AGR often occurs suddenly, and routine examinations of white cell counts may not prevent its occurrence. In Japan, death was reported of a patient with Graves' disease who was administered ATD approximately once a year.

Under the Medical Practitioners Law, doctors in Japan should report adverse drug reactions to pharmaceutical companies that should collect from the medical institutions' detailed information, including age, sex, time to onset of adverse reaction, dose at time of onset, adverse reaction type and severity, examination data, treatment details, and outcome. We analyzed the reported cases of AGR.

As of April 2011, the pharmaceutical company has collected information from a total of 733 cases of Graves' disease in patients treated with ATD since 1981. Among them, 215 patients had white cell count measurements within 90 days before the onset of AGR. The duration between the last examination and the onset was continuous between one and 82 days. Surprisingly, normal granulocyte counts were confirmed in 64 patients (30%) within one week before onset and in 131 patients (61%) two weeks before onset. This shows that AGR develops rapidly. Thirty patients died, including two old cases from our hospital. Excluding six cases with insufficient information reported, we analyzed 24 patients. Based on physician reports in 14 cases, there might be some room for improvement of therapeutic procedures, for example, giving patients more sufficient ATD safety information, careful differential diagnosis of AGR from common cold, and stopping ATD immediately when AGR is suspected. On the contrary, it might have been very difficult to save the lives of 10 patients, because the granulocyte counts just a few days before were normal, or because the condition of the patient was deteriorating very rapidly without responding to promptly administered intensive care.

This study provides the first direct evidence that AGR develops rapidly. Giving sufficient information on AGR to every patient is very important when ATD is prescribed.

1 Endocrinology & Metabolism, M S Ramaiah Medical College, Bangalore, India 2 Endocrinology, PRIMER, Bangalore, India Poster 40 COMPARISON OF EFFICACY OF TWO FIXED DOSES OF ¹³¹I RADIOIODINE THERAPY (5 VS. 10 mCi) IN FEMALE PATIENTS WITH GRAVES' DISEASE

Autoimmunity Thursday Poster Clinical

The optimal method for determining ¹³¹I treatment doses for Graves' disease (GD) is controversial. Fixed dosing and calculations based upon gland size, iodine uptake, and iodine turnover are used. The objective of this retrospective analysis was to compare the 1-year outcomes of 2 fixed doses of ¹³¹I radioiodine therapy (5 vs. 10 mCi) in newly diagnosed female patients with GD.

The clinical outcome of 227 female patients with GD treated with ¹³¹I at initial diagnosis from 1998 to 2006 was evaluated. Seventy-seven patients received 5 mCi of ¹³¹I, and 150 patients received 10 mci. All the patients in the study group were followed-up for at least 12 months after ¹³¹I treatment. Independent samples Student's t-test and Chi-squared tests were used to compare baseline parameters and assess the difference in outcomes between the two groups at 1 year. The predictors of remission were determined by logistic regression.

The mean age of the sample was 38±10.8 yrs. Baseline total T4 was higher in the 10-mCi group than the 5-mCi group (p<0.01%). In other aspects, both groups were comparable. The overall success rate of single dose of radioiodine was 92.5% (90.9% 5-mCi group, 93.2% 10-mCi group). One year after ablation, 81.8% of patients in the 5-mCi group were hypothyroid; 9.1% were euthyroid; and 9.1% had relapsed. The corresponding rates for the 10-mCi group were 78.6%, 14.6%, and 6.8%. The outcomes were not different between the two groups by Chi-squared tests. Age, weight, height, baseline T4, and TPO positivity were not predictors of successful treatment in logistic regression. Worsening of ophthalmopathy was seen in one patient in the 5-mCi group and in 3 patients in the 10-mCi group.

Ten mCi of radioiodine was no more effective than 5 mCi in female patients with GD. We recommend that a routine use of 10 mCi in a fixed-dose approach is not warranted in GD.

1 Department of Medicine, Section of Endocrinology, Tulane University School of Medicine, New Orleans, LA 2 Department of Medicine, Division of Endocrinology, The University of Tennessee Health Science Center, Memphis, TN Poster 42 HYPERTHYROIDISM CAUSED BY GRAVES' DISEASE IN A PATIENT WITH END-STAGE RENAL DISEASE ON HEMODIALYSIS

Autoimmunity Thursday Poster Clinical

We describe a case of hyperthyroidism secondary to Graves' disease in a patient with end-stage renal disease (ESRD) on hemodialysis (HD), highlighting the complexities of treatment with radioactive iodine (RAI).

A 34-year-old woman with a medical history of ESRD on HD was referred to an endocrine clinic for evaluation and treatment of recently diagnosed hyperthyroidism. She reported a 50-lbs. weight loss in one month, palpitations, and increase in the neck size. Physical examination revealed a heart rate of 114 bpm, hand tremors, and thyromegaly without any audible bruit. Thyroid function tests were consistent with severe hyperthyroidism. Thyroid-stimulating immunoglobulin levels were elevated. Thyroid ultrasound showed diffusely increased size and vascularity of the gland. RAI uptake and scan was performed 24 hours after HD: uptake of 73.9% (4–16) at 4 hours. She was pretreated with methimazole and propranolol for 10 weeks. After detailed communications between endocrinology, nephrology, and nuclear medicine, she was given 12 millicuries of ¹³¹I, 24 hrs after and before HD.

¹³¹I is mainly cleared by the kidneys in patients with normal renal function; hence, many issues arise in patients who are on HD, including modification of dose and optimal timing of HD after ¹³¹I therapy to maximize treatment benefit while minimizing risk to the patient and dialysis personnel. Fewer than 15 similar cases have been reported in the literature so far. Although the dose of ¹³¹I need not be adjusted for HD patients, first dialysis after RAI therapy must be delayed until maximum uptake has occurred in the thyroid, which is approximately 10 hours for patients with normal renal function as well as on HD. Radiation monitoring and precautions should be continued for several weeks after treatment as the thyroid continues to process and secrete ¹³¹I for several weeks.

¹³¹I may be used as definitive treatment of hyperthyroidism in patients with ESRD on HD. However, the optimal dose and timing of HD post-treatment require careful consideration and interdisciplinary communications to minimize risks to patients and medical personnel.

1 Ciencias Biológicas, Universidad Nacional Andrés Bello, Santiago, Chile 2 Ciencias Biológicas, Millenium Institue of Inmunology and Inmunotherapy, Santiago, Chile 3 Genética Molecular y Microbiología, Pontificia Universidad Católica, Santiago, Chile 4 Reumatología, Pontificia Universidad Católica, Santiago, Chile 5 Pathology, Albert Einstein College of medicine, Bronx, NY Poster 43 HYPOTHYROIDISM DURING PREGNANCY INCREASES THE SEVERITY OF EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS IN THEIR ADULT OFFSPRING

Disorders of Thyroid Function Thursday Poster Basic

Maternal thyroid hormones (MTH) during gestation play an essential role for the appropriate development of the fetus central nervous system (CNS). Among other things, MTH are involved in neuronal development, such as neurite outgrowth, neuronal migration, synapse formation, neuroglial cell development, number of oligodendrocytes, and its myelination. Even though there are few reports in the literature that suggest that MTH are important for the offspring immune system, we show in this work that mice that were gestated in a hypothyroidism condition suffer a strong autoimmune disease at the CNS. Multiple sclerosis (MS) is a chronic autoimmune disease at the CNS characterized by autoimmune reaction, inflammation, demyelination, and axonal damage. Patients that suffer MS have muscle weakness, cognitive impairment, and physical disability among other symptoms.

Mice gestated in mothers with MTH were induced with experimental autoimmune encephalomyelitis (EAE) as a murine model for MS. After 21 days of induction, spinal cord slices were analyzed for demyelination, immune cell infiltration, and oligodendrocyte cells death. To analyze the effects of MTH during pregnancy on oligodendrocyte viability after tumor necrosis factor α (TNFα), primary oligodendrocyte cultures were performed from rats gestated in MTH.

We have shown that the offspring gestated in a hypothyroidism condition suffer a strong EAE than mice gestated in an euthyroid condition. The offspring gestated in a hypothyroid condition showed a higher EAE score, demyelination, immune cell infiltration, and oligodendrocyte cell death than mice gestated in the euthyroid condition. In vitro studies using primary oligodendrocyte cell culture obtained from the offspring gestated in hypothyroid condition showed increase cell death in the presence of TNFα.

These results suggest for the first time that hypothyroidism during gestation can impair the outcome of an inflammatory CNS disease, such as EAE in the offspring. These data strongly support the need for thyroid hormone diagnosis for pregnant women and the treatment of hypothyroidism during pregnancy. Funding: Fondecyt 1100926, Proyecto Interno UNAB DI-11-11/R Millennium Institute on Immunology and Immunotherapy (MIII) P09-016-F.

1 Endocrine Unit, San Francisco VA Medical Center, University of California, San Francisco, CA 2 Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 3 Endocrinology Metabolism Diabetes & Nutrition, Mayo Clinic Rochester, Rochester, MN 4 Division of Endocrinology, College of Physicians & Surgeons, Columbia University, New York, NY 5 Section of Endocrinology, University of Chicago, Chicago, IL 6 Clinical Development & Medical Affairs, NPS Pharmaceuticals, Bedminster, NJ Poster 48 EFFICACY OF RECOMBINANT HUMAN PARATHYROID HORMONE (RHPTH[1–84]) FOR THE TREATMENT OF ADULTS WITH HYPOPARATHYROIDISM: POSTSURGICAL VS. NONSURGICAL ETIOLOGY

Disorders of Thyroid Function Thursday Poster Clinical

Hypoparathyroidism (HypoPARA) is a rare endocrine disorder characterized by absent or low levels of parathyroid hormone (PTH), leading to hypocalcemia and hyperphosphatemia. Therapy is limited to symptomatic management with large doses of calcium (Ca) and calcitriol; however, their long-term use may lead to complications.

A phase III randomized, double-blind, placebo (PBO)-controlled, 24-week study assessed whether recombinant human parathyroid hormone (rhPTH[1–84]) reduced Ca and calcitriol needs, while normalizing or maintaining albumin-corrected total serum Ca levels in HypoPARA. Patients received 50 μg/day SC injections of rhPTH(1–84) or PBO; dose escalation up to 75 and then to 100 μg/day was permitted if calcitriol and oral Ca supplements could be further reduced. Of the 134 randomized patients, 53% of rhPTH(1–84) and 2% of PBO-treated patients were responders (p<0.001; defined as patients whose need for oral Ca and calcitriol could be reduced by 50% at week 24 while maintaining a serum Ca level of ≥baseline). rhPTH(1–84) treatment was generally well tolerated, with hypocalcemia, muscle spasm, paresthesia, headache, and nausea being the most common adverse events. Here we report the efficacy of rhPTH(1–84) in those who developed HypoPARA postsurgery (n=99) and those due to nonsurgical causes (n=35).

HypoPARA resulted from surgery in 76% of rhPTH(1–84) and 71% of PBO patients. Nonsurgical causes included genetic disorder, radiation exposure, autoimmune, or idiopathic disease. Within the postsurgical subgroup, a significantly higher proportion of rhPTH(1–84) patients were responders compared to PBO (57% [39/68] vs. 3% [1/31]; p<0.001). This was also observed within the nonsurgical subgroup with a significantly higher response rate among rhPTH(1–84) patients compared to PBO (41% [9/22] vs. 0% [0/13]; p=0.0131). Among rhPTH(1–84)-treated patients, the response rate was similar, but not statistically significant between the postsurgical and nonsurgical subgroups.

A high proportion of both subgroups responded to rhPTH (1–84), suggesting that surgical or nonsurgical etiology does not impact the efficacy of rhPTH(1–84) for treatment of patients with HypoPARA.

1 Endocrinology, McGill University, Montreal, QC, Canada 2 Surgery, McGill University, Montreal, QC, Canada Poster 51 GRAVES' DISEASE FOLLOWING HEMITHYROIDECTOMY FOR THYROID NODULE MARIE-DIBA EID, ROGER TABAH AND JACQUES HOW, DIVISION OF ENDOCRINOLOGY AND DEPARTMENT OF SURGERY, MONTREAL GENERAL HOSPITAL, MCGILL UNIVERSITY HEALTH CENTER

Disorders of Thyroid Function Thursday Poster Clinical

It is now recognized that thyroid autoimmunity, including Graves' disease, can occur after radioactive iodine treatment for nonimmune thyroid nodular disorders. In contrast, Graves' disease as a sequelum of thyroid surgery for thyroid nodules is less well known. We describe two patients who were documented to have Graves' hyperthyroidism after hemithyroidectomy for thyroid nodule.

Case 1: A 32-year-old female patient with a 5-cm nodule in the right thyroid lobe. Euthyroid and test for anti-TPO antibody negative. Strong family history of thyroid disease, involving her mother and 3 maternal aunts. Right hemithyroidectomy was carried out, and the final pathology was benign. Subsequently, developed a cystic lesion in the left lobe, for which she underwent multiple aspirations. Nine years after the hemithyroidectomy, she became thyrotoxic, and tests for both anti-TPO and TSH-receptor antibodies became strongly positive. There was increased uptake by the left lobe on thyroid scanning. The patient was treated with radioactive iodine.

Case 2: A 28-year-old female patient with a nodule in the left thyroid lobe, suspicious for a follicular neoplasm. TSH normal and anti-TPO antibody negative. Both parents have hypothyroidism. Left hemithyroidectomy carried out with benign pathology. Eight years later, she developed hyperthyroidism and ophthalmopathy with positive anti-TPO and TSH receptor antibodies. Thyroid uptake was increased at 53% with homogeneous distribution of the tracer. She was treated with Methimazole.

The development of thyroid autoimmunity after thyroid surgery for nonimmune nodular disease is unusual. There is a plausible mechanistic explanation for this sequence. It is postulated that the surgical intervention caused the release of an excess amount of thyroid antigens, and in susceptible persons, this could trigger an immune response to the appropriate antigens, including the TSH receptor. Documentation and study of such cases are not only clinically relevant but also pertinent to understanding the repertoire of pathogenetic mechanisms in thyroid autoimmunity.

1 Endocrinology, Diabetes, and Metabolism, Duke University Hospital, Durham, NC 2 Gastroenterology, Duke University Hospital, Durham, NC 3 Statistical Science, Duke University Hospital, Durham, NC 4 Pathology, Duke University Hospital, Durham, NC Poster 55 THE ASSOCIATION OF SERUM THYROID HORMONE LEVELS AND HEPATIC GENE EXPRESSION OF POTENTIAL REGULATORS OF INTRACELLULAR THYROID HORMONE CONCENTRATION WITH SEVERITY OF NONALCOHOLIC FATTY LIVER DISEASE

Thyroid Hormone Metabolism & Regulation Thursday Poster Translational

Nonalcoholic fatty liver disease (NAFLD) is strongly associated with dyslipidemia, metabolic syndrome, and hypothyroidism. Whether serum thyroid hormone (TH) levels are associated with NAFLD disease severity is unclear. Objective: To define serum TH levels and thyroid-related liver gene expression differences between early and advanced NAFLD.

RNA was extracted and microarray performed from liver tissue of 70 patients with biopsy-proven NAFLD (42 early NAFLD and 28 advanced). Serum collected on the same day as biopsy was analyzed for thyroid-stimulating hormone (TSH), free T4 (fT4), free T3 (fT3), and reverse T3 (rT3). TH levels were compared between early vs. advanced NAFLD using Wilcoxon Rank-Sum tests. Logistic regression models were built with severity as the outcome and serum marker as the covariate. Differential gene expression was determined on normalized data by an empirical Bayes method with a 5% False Discovery Rate control.

No difference in age, gender, ethnicity, or history of hypothyroidism was noted in patients with early vs. advanced NAFLD. Diabetes mellitus was more prevalent in those with advanced NAFLD (p<0.01). Hyperlipidemia was more prevalent in early NAFLD (p=0.039). Serum fT3 was higher (p=0.024) and rT3 lower (p=0.004) in early vs. advanced NAFLD. After adjusting for age and BMI, fT3 and rT3 remained significant (p=0.026 and p=0.03, respectively). The fT3/rT3 ratio was lower in those with advanced NAFLD (p=0.001, adjusted p=0.007). Gene expression analysis revealed increased expression of THRSP in early NAFLD and increased expression of tissue-remodeling genes in advanced NAFLD (IGFBP6, RCAN2, and ITGAV). Spearman's rank correlations indicate a significant positive relationship between the serum fT3 and fT3/rT3 ratio, with RAC3 expression (ρ=0.55, ρ=0.46) (p<0.001), a gene important in morphogenesis and cellular migration.

Early NAFLD is associated with higher fT3 and lower rT3 levels than to advanced NAFLD. There are unique thyroid-specific gene expression differences in early vs. advanced disease. Our findings suggest that TH levels and/or hepatic responsiveness to TH may contribute to NAFLD disease severity.

1 Endocrinology, Diabetes, and Metabolism, Duke University Medical Center, Durham, NC 2 Gastroenterology, Duke University Medical Center, Durham, NC Poster 56 HEDGEHOG AND MEDULLARY THYROID CANCER: A NOVEL, SIGNALING PATHWAY

Thyroid Cancer Thursday Poster Basic

Hedgehog (Hh) signaling is a morphogenic pathway involved in cell fate decisions in many endodermally derived adult tissues. Hh signaling is critical in migration, differentiation, and growth of progenitor cell populations. Recent reports have established that Hh signaling is present in thyroid tumors, specifically follicular adenomas, papillary, and anaplastic thyroid cancers. No report has established that this cell-signaling pathway is present in medullary thyroid cancer (MTC). Objective: To determine if the Hh signaling pathway is present in endodermally derived parafollicular cells, specifically MTC.

Using both human thyroid tissue and established MTC human cell cancer lines, we used immunohistochemical (IHC) staining, quantitative real-time PCR, and Western Blot to determine presence of Hh in parafollicular cells. We manipulated Hh using various concentrations of SAG (0–2 uM), a compound shown to induce Hh activation through canonical signaling pathways, and GDC-0449 (Vismodegib) (0–10uM), a potent antagonist of Hh signaling.

Hh signaling is upregulated in MTC compared with normal thyroid tissue by IHC. Sonic Hedgehog (Shh) and Glioblastoma Family 2 (Gli2), a downstream target of Hh, are highly expressed in human MTC. Established human MTC cells lines, TT and MZ-CRC-1, were grown in F12K media+10% FBS+Pen/Strep and DMEM 1×Glucose+10% FBS+Pen/Strep, respectively. Cell lines were treated with SAG and GDC-0449 as varying concentrations. A dose–response curve showed that Hh activity in these MTC cell lines was only minimally activated by SAG, but significantly inhibited by GDC-0449 at doses of 0.4, 2, and 10 uM. GDC-0449 downregulation of Hh signaling was documented at the mRNA level and at the protein level. Cell Counting Kit-8 (CCK-8) was utilized and showed that at 24, 48, and 72 hours, SAG significantly increased cell number, whereas GDC significantly reduced cell number after treatment.

Hh signaling is a novel pathway in medullary thyroid cancer. It can be manipulated by canonical signaling agents: SAG and GDC-0449. Reduction of cell number with GDC-0449 as determined by CCK-8 assay suggests that this pathway may be important for novel drug therapy in MTC.

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POSTER 56.

Hh signaling is upregulated in MTC compared with normal thyroid tissue by IHC. Sonic Hedgehog (Shh) and Glioblastoma Family 2 (Gli2), a downstream target of Hh, are highly expressed in human MTC.

1 Pathology, University of Pittsburgh, Pittsburgh, PA 2 Pathology, University of Bern, Switzerland, Bern, Switzerland 3 Pathology, Triemlispital Zuerich, Zuerich, Switzerland 4 Pathology, University Hospital Zurich, Zuerich, Switzerland Poster 58 MICRO-RNA EXPRESSION PROFILES IN FOLLICULAR VARIANT OF PAPILLARY THYROID CARCINOMAS

Thyroid Cancer Thursday Poster Basic

The follicular variant of papillary carcinoma (FVPTC) shares features of papillary (PTC) and follicular (FTC) thyroid carcinomas. While the clinical course and the nuclear features are closer to PTC, the pattern of growth resembles FTC. We characterize the miRNA profile of the follicular variant of papillary carcinoma (FVPTC) and correlated it with clinicopathological data.

Seventeen (17) FVPTC, 27 classic PTC, and 8 normal thyroid tissues were studied for expression of 768 miRNAs using Human Microarray Assays (Applied Biosystems) on ABI 7900. miRNAs were isolated using the RecoverAll Total Nucleic Acid kit (Ambion) from FFPE tissue specimens (n=52). Data Assist, Statminer, and SPSS program were used for data analysis.

We found 14 miRNAs in the FVPTC to be significant dysregulated with a fold change of more than 5 (up/down). miRNAs that previously found to be upregulated in classic PTC, including miR-221, 222, and 146b, were strongly upregulated in FVPTC. In addition, novel miRNAs were found to be dysregulated in FVPTC, including miR-375, 551b, 181-2-3p, and 99b-3p. The latter two showed a significant adverse outcome in a Kaplan–Meier analysis, which was confirmed by multivariate-analysis (Cox regression).

Despite high similarity in miRNA expression between classic papillary carcinoma and follicular variant of PTC, several miRNAs were unique for FVPTC and showed association with adverse outcome. Strongly upregulated miRNA (miR-375) could serve as a novel diagnostic marker for papillary thyroid carcinoma.

1 Department of Otolaryngology-Head and Neck Surgery, McGill University, Montreal, QC, Canada 2 Department of Pathology, McGill University, Montreal, QC, Canada Poster 59 FROZEN SECTION ANALYSIS AND SENTINEL LYMPH NODE BIOPSY IN WELL-DIFFERENTIATED THYROID CANCER

Thyroid Cancer Thursday Poster Basic

The aim of this study was to prospectively review the role of sentinel lymph node (SLN) biopsy in the management of well-differentiated thyroid carcinoma (WDTC), and to determine the efficacy of intraoperative frozen-section analysis at detecting SLN metastasis and central compartment involvement.

The SLN biopsy protocol using 1% methylene blue was performed in 271 patients undergoing thyroidectomy for WDTC. A central compartment neck dissection (CCND) was performed on all patients. Lymph nodes staining blue were considered as SLNs. Both frozen- and permanent-section analyses were performed.

SLNs with metastasis were found in 14.8% (40/271) of cases. Of this, 11.4% (31/271) were positive on intraoperative frozen-section analysis. Frozen-section results failed in predicting central compartment involvement in 14 cases (5.2%), whereas central neck compartment involvement was missed in 5 cases (1.8%) when based on permanent-section results. On frozen-section analysis, the sensitivity, specificity, positive predictive value, and negative predictive value (95% CI) of our SLN biopsy technique aiming to remove all disease from the central compartment were 68.9% (53.2; 81.4), 100% (97.9; 100), 100% (86.3; 100), and 94.2% (90.2; 96.7), respectively, with p<0.0001. On permanent-section analysis, the values were 88.9% (75.2; 95.8), 100% (97.9; 100), 100% (89.1; 100), and 97.8% (94.8; 99.2) with p<0.0001.

These data series demonstrate that patients with WDTC have positive SLNs in 14.8% of cases. Moreover, when the SLNs are negative for metastasis on frozen section, the central compartment was disease-free in 94.2% of cases. Finally, this study shows that 22.5% of positive SLNs were false negatives on intraoperative frozen section. According to these data, SLN involvement is an accurate predictor of central compartment metastasis; however, surgeons should use caution when relying on intraoperative frozen section to determine whether to perform a CCND.

1 Internal Medicine, Endocrine and Metabolic sciences and Biochemistry, University of Siena, Siena, Italy 2 Department of Biology and Molecular and Cellular Pathology "L. Califano", University of Naples, Naples, Italy 3 Department of Human Pathology and Oncology, University of Siena, Siena, Italy Poster 61 EXPRESSION OF THE RING LIGASE PRAJA2 IN THYROID CANCER

Thyroid Cancer Thursday Poster Basic

Praja2 is a RING ligase, which degrades regulatory subunits of PKA, thus controlling the strength and duration of PKA signal in response to cAMP. TSH, through activation of its receptor, increases cAMP inside the cells, sustaining tyrocyte growth and hormone production. Differentiated thyroid cancer (DTC) is a TSH-dependent tumor, and its function is modulating by TSH levels. We aimed to analyze the expression of PRAJA2 in a group of 36 DTC, 14 benign nodules, and 6 anaplastic thyroid cancer (ATC).

To this purpose, we measured mRNA levels by real-time RT-PCR and protein by western blot and immunohistochemistry. Possible association between PRAJA2 mRNA and presence of known mutations was evaluated.

We found a statistically significant (p<0.001) increase of mRNA levels in PTC compared to benign nodules and ATC. In particular, PRAJA2 RNA expression was maximal in well-differentiated histological variants and decreased progressively with loss of differentiation, ATC having the lower expression. Western blot revealed that PRAJA2 mRNA was translated into a functional protein with OD arbitrary units for PTCs significantly higher (p<0.001) compared to the benign nodules without data overlapping. By immunohistochemistry, we observed a marked cytoplasmatic localization of PRAJA2 in PTCs, which decreased in the less-differentiated variants and completely disappeared in the ATC. We then measured mRNA levels in three different cell lines stably expressing BRAFV600E mutation, RET/PTC1, and RET/PTC3 rearrangements. We observed a significant (p<0.01) increase in mRNA expression in RET/PTC1-positive cells compared to RET/PTC3, but not against BRAF-positive cells. Similar results were obtained with cancer tissues with the same mutations. Analysis of the clinical data showed that protein expression was not associated with outcome, TNM, and tumor diameter.

PRAJA2 is markedly overexpressed in DTC, and its protein expression decreases together with tumor dedifferentiation. The expression might be linked to the mutational status of the tumor.

1 Otolaryngology-Head and Neck Surgery, Johns Hopkins, Baltimore, MD 2 Surgery, Johns Hopkins, Baltimore, MD 3 Pathology, Johns Hopkins, Baltimore, MD 4 Oncology, Johns Hopkins, Baltimore, MD 5 Immunobiology, Yale, New Haven, CT Poster 62 INSIGHT INTO THE PD-1/PD-L1 IMMUNOSUPPRESSIVE PATHWAY IN PAPILLARY THYROID CANCER

Thyroid Cancer Thursday Poster Translational

PD-L1, a protein displayed by many tumors, binds the PD-1 co-inhibitory receptor on activated T cells, leading to immunosuppression. Blockade of the PD-1/PD-L1 pathway has shown promising clinical results in patients with treatment-refractory solid tumors. In the current study, we assessed the presence of PD-1+T-cells in the tumor microenvironment, as well as tumor cell expression of PD-L1, to better characterize this novel mechanism of immune escape in papillary thyroid cancer (PTC).

Patients diagnosed with PTC who were undergoing surgical resection were eligible for the study. Mononuclear cells were isolated from the peripheral blood, primary thyroid tumor, and contralateral normal thyroid tissue (CNT). From these mononuclear cells, T-cell populations were evaluated for the expression of CD4, CD8, CD45, CD3, and PD-1 using multicolor flow cytometry. In addition, these same cell populations were evaluated in multinodular hyperplasic (MNH) specimens (benign control). Surgical PTC specimens were also analyzed by immunohistochemistry for expression of PD-L1.

CD4+/PD-1+ T-cells were increased in tumors and CNT when compared to blood (means: 63.90%, 64.20%, and 8.03%, respectively, p=0.0079). Cytotoxic CD8+/PD-1+ T-cells were also increased in tumors and CNT when compared to blood (means: 69.40%, 66.0%, and 17.3%, respectively, p=0.016). In MNH, there was no observed difference in CD8+ or CD4+ T-cell frequencies between blood and tissue. In PTC, membranous staining of PD-L1 was observed in 89% of specimens.

We identified an increase in CD4+/PD-1+ and CD8+/PD-1+ T-cells in PTC when compared to blood or MNH. In addition, membranous expression of PD-L1 was observed in PTC, suggesting that the presence of PD-1+ T cells may be driving tumor cell expression of PD-L1 to create an immunosuppressive microenvironment, a mechanism that we term adaptive immune resistance. Further studies are needed to identify individual factors produced by T-cells that drive PD-L1 expression in the tumor cells. It is the eventual hope that blockade of the PD-1/PD-L1 pathway will offer a clinical benefit to patients with treatment-refractory PTC.

1 Internal Medicine, Asan Medical Center, Seoul, Republic of Korea 2 Asan Institute for Life Science, Asan Medical Center, Seoul, Republic of Korea Poster 64 XIAP INHIBITOR INDUCES APOPTOSIS IN BRAF V600E-MUTANT THYROID CANCER CELL LINES

Thyroid Cancer Thursday Poster Translational

X-linked inhibitor of apoptosis protein (XIAP) is a member of the inhibitor of the apoptosis (IAP) protein family that selectively blocks caspases-3, 7, and 9, and inhibits cell death. Embelin, an XIAP inhibitor, is known to exhibit anti-inflammatory and apoptotic activities. Recent reports suggest that embelin interferes the signal transducer and activator of transcription 3 (STAT3) pathway and the nuclear factor-kB (NF-kB) signal pathway. In this study, we investigated the anticancer efficacy of embelin by measuring its effects on apoptosis of thyroid cancer cell lines. We also explored the mechanism underlying these effects.

We used cell viability assay and apoptosis assay to analyze the effects of embelin in thyroid cancer cell lines such as FTC-133, CAL-62, KTC-1, and 8505C. We used western blotting to establish the effect of embelin on the p38 pathway.

We found that embelin induced the apoptosis of human thyroid cancer cell lines. The effect was more prominent in BRAF V600E-mutant thyroid cancer cell lines (KTC-1 and 8505C) than in BRAF wild-type cell lines (FTC-133 and CAL-62). The effect of embelin on cell apoptosis was associated with increased phosphorylation of p38. SB203580, a specific inhibitor of p38-MAPK, inhibited the embelin-mediated induction of cleaved caspase-3 activity in V600E-mutant thyroid cancer cell lines. Interestingly, embelin induced apoptosis in BRAF wild-type cancer cell lines, even after treatment of SB203580. These results indicated that another signaling pathway, not a p38 pathway, might be responsible for embelin-induced apoptosis in BRAF wild-type thyroid cancer cell.

Embelin-induced XIAP suppression resulted in an increase of apoptosis via phosphorylation of p38 in BRAF V600E-mutant thyroid cancer cell lines. Regulation of XIAP activity may be potentially useful as a treatment of thyroid cancer, especially in BRAF V600E-mutant thyroid cancer.

1 Surgery, University of Pittsburgh, Pittsburgh, PA 2 Endocrinology, University of Pittsburgh, Pittsburgh, PA 3 Pathology, University of Pittsburgh, Pittsburgh, PA Poster 65 MUTATIONAL TESTING PANEL PREDICTS PAPILLARY THYROID CANCER RECURRENCE IN LONG-TERM FOLLOW-UP

Thyroid Cancer Thursday Poster Clinical

Recurrence develops in ∼20% of patients with papillary thyroid cancer (PTC). Molecular testing is increasingly utilized in the management of PTC. However, as a novel technique, few studies with sufficient follow-up are available to assess the impact of its results on PTC recurrence. The aim of the present investigation was to examine the predictive ability of clinicopathologic parameters, including mutation testing, for PTC recurrence with long-term follow-up.

We conducted a single-center retrospective review of clinicopathologic characteristics in a consecutive series of PTC patients who had initial operation between 6/99 and 12/01, archived tissue available for molecular testing, and >1 year clinical follow-up. Retrospective molecular testing was performed for BRAFV600E, NRAS61, HRAS61, and KRAS12/13 mutations, and RET/PTC1 and RET/PTC3 rearrangements. Recurrence was diagnosed if 1) there was pathologic or cytologic confirmation of disease after reoperation, or 2) radiographic imaging demonstrated local or distant metastasis.

Analysis included 80 patients with a mean age of 46 years (range 13–78) and mean follow-up of 102 months (range 12–149). The recurrence rate was 19% (15/80) with mean time to recurrence of 55 months (range 1–133). The incidence of mutation-positive PTC detected by the study panel was 55/80 (69%). All 15 recurrences were mutation positive (12 BRAFV600E, 1 HRAS61, and 2 RET/PTC1), and no recurrences occurred in the 25/80 patients who were mutation negative, resulting in 27% PPV and 100% NPV for the panel in predicting PTC recurrence. Recurrence was also associated with extrathyroidal extension (p=0.03), lymph node metastasis (LNM) (p=0.001), and TNM stage III/IV (p=0.008) at presentation, but not with age >45 years (p=0.06), male gender (p=0.55), or PTC size >2 cm (p=0.05). Only LNM predicted recurrence on multivariable analysis (p=0.013).

With long-term follow-up, only mutation panel results and LNM at presentation were predictors of PTC recurrence. To optimize surveillance strategies, the routine use of molecular testing to identify PTC patients at risk for recurrence should be strongly considered.

1 Surgery, Eulji University College of Medicine, Seoul, Republic of Korea 2 Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea Poster 66 A COMPARATIVE ANALYSIS OF THE ONCOLOGICAL OUTCOMES AND THE QUALITY OF LIFE AFTER ROBOTIC AND CONVENTIONAL OPEN THYROIDECTOMY WITH MODIFIED RADICAL NECK DISSECTION IN PATIENTS WITH PAPILLARY THYROID CARCINOMA WITH LATERAL NECK NODE METASTASIS

Thyroid Cancer Thursday Poster Clinical

Robotic total thyroidectomy (TT) with modified radical neck dissection (MRND) using a gasless transaxillary approach has been reported a safe and effective procedure with notable cosmetic benefits. In his study, we compared the oncological outcomes and quality of life in patients undergoing robotic TT and MRND with outcomes of those treated by conventional open procedures.

Between March 2010 and July 2011, 86 papillary thyroid carcinoma patients with lateral neck node metastasis were enrolled in this study; 40 underwent a robotic TT with MRND (robot group); and 46 an open TT with MRND (open group). These two groups compared in terms of their oncologic outcomes and safety as well as functional outcomes such as postoperative subjective voice or swallowing difficulties. Moreover, neck pain, discomfort, stiffness, sensory change, and cosmetic satisfaction after surgery were also evaluated using a modified quality-of-life symptom scale. An arm abduction test (AAT) and questions modified from neck dissection impairment index (NDII) were applied to all patients to measure neck and shoulder disability.

Although the mean operating time was significantly longer in the robotic group than in the open group, there were no significant differences in postoperative complication rates and oncologic outcomes, including the results of RI scans and serum Tg levels after surgery. The results of subjective voice and swallowing parameters were also similar. Postoperative neck stiffness and sensory change were significantly more frequent in the open group than in the robotic group. In particular, the mean cosmetic satisfaction score was significantly higher in the robotic compared to the open group. Although the recovery time of shoulder movement trends toward a little longer in the robot group, the results of postoperative AAT and NDII were not significantly different in the robotic group compared with the open group.

Robotic TT with MRND was found to be similar to conventional open procedures in terms of oncologic outcomes and safety. Moreover, this robot technique could offer several benefits for quality of life, including excellent cosmetic results, reduced postoperative neck stiffness, and sensory change.

1 Surgery, Eulji University College of Medicine, Seoul, Republic of Korea 2 Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea Poster 67 LONG-TERM OUTCOMES OF TOTAL THYROIDECTOMY VERSUS LOBECTOMY FOR PAPILLARY THYROID MICROCARCINOMA

Thyroid Cancer Thursday Poster Clinical

To compare long-term outcomes after total thyroidectomy (TT) or thyroid lobectomy (LT) in a large cohort of patients with papillary thyroid microcarcinoma (PTMC), and to determine whether the tumor size (≤0.5 cm versus >0.5 cm) has a significant impact on the extent of surgery.

We evaluated 2014 patients with PTMC who underwent TT (n=1015) or LT (n=999) between March 1986 and December 2006 and for whom complete follow-up data were available for at least 5 years (median 11.8 years; range 5–26 years). Using propensity score (PS) matching to reduce the impact of treatment selection bias and potential confounding in an observational study, we compared overall survival (OS) and disease-free survival (DFS) in the overall cohort and in patients with tumors ≤0.5 cm and >0.5 cm in size.

After adjustment for differences in baseline clinicopathologic risk factors, we observed no significant differences between the LT and the TT groups in the risk of death (hazard ratio [HR] for the LT group, 1.05; 95% confidence interval [CI] 0.71 to 1.47, p=0.891) and locoregional recurrence (HR for the LT group, 3.08; 95% CI 1.99 to 8.05, p=0.194) in the overall matched cohort. Similar results were observed when we compared LT and TT in patients with tumors ≤0.5 cm and >0.5 cm.

The long-term rates of death and locoregional recurrence were similar in patients with PTMC who underwent LT and those who underwent TT. Moreover, the tumor size 0.5 cm was not a significant determinant of the extent of surgery in patients with PTMC.

1 Faculty of Medicine, McGill, Montreal, QC, Canada 2 Otolaryngology Head and Neck Surgery, McGill University Health Center, Montreal, QC, Canada 3 Otolaryngology Head and Neck Surgery, Jewish General Hospital, Montreal, QC, Canada 4 Pathology, McGill University Health Center, Montreal, QC, Canada Poster 68 COMPLETION THYROIDECTOMY: ARE THERE CHARACTERISTICS OF THE INITIAL THYROID CARCINOMA THAT PREDICT MALIGNANCY IN THE CONTRALATERAL LOBE?

Thyroid Cancer Thursday Poster Clinical

The goal of this study was to (1) determine the incidence of well-differentiated thyroid cancer (WDTC) in the contralateral thyroid lobe in patients undergoing completion thyroidectomy, and (2) identify features of the malignant tumor in the initial resection that increase the likelihood of malignancy in the contralateral lobe.

The medical records of consecutive patients (n=98) undergoing completion thyroidectomy between 2006 and 2012 at the McGill University Thyroid Cancer Centre were retrospectively reviewed. Pathology reports from the initial surgery and the completion thyroidectomy were reviewed. Other patient and thyroid nodule characteristics ascertained by the McGill Thyroid Nodule Score (ultrasound findings, exposure to ionizing radiation, etc.) were recorded as well. The group was divided based on final pathology findings following completion thyroidectomy (malignant vs. benign). The Independent T test and the two-tailed Fisher's exact test were used to assess statistical significance of correlation between the individual measured variables and recurrence.

Of the 98 patients, 48 (49%) had a malignancy in the contralateral lobe. The mean age of both groups were similar 46 vs. 48.2 (malignant vs. benign). The mean time to completion was 103 days (125.1 malignant vs. 82.3 benign). In the contralateral lobe, 89% (43/48) of malignancies were micropapillary carcinomas, and 40% (19/48) of malignancies were multifocal. The presence of at least one focus of micropapillary carcinoma in the initial hemithyroidectomy was associated with a 60% chance of malignancy in the completion thyroidectomy (p=0.042). There was no statistical significant correlation established for the following variables: presence of positive cervical nodes, extrathyroidal extension, positive resection margins, size, encapsulated tumors, angiolymphatic invasion, and the subtype of WDTC. Moreover, there was no correlation between any of the variants of papillary thyroid cancer and recurrence.

In this study, the rate of malignancy in the contralateral lobe was 49%. The presence of at least one focus of micropapillary carcinoma in the initial hemithyroidectomy was found to be a predictor of contralateral malignancy.

1 General Surgery, University of British Columbia, Vancouver, BC, Canada 2 General Surgery, St. Paul's Hospital, Vancouver, BC, Canada Poster 69 PAPILLARY THYROID MICROCARCINOMA: THE SIGNIFICANCE OF HIGH-RISK FEATURES

Thyroid Cancer Thursday Poster Clinical

The current guidelines for surgical management of papillary thyroid microcarcinoma (PTMC) are largely based upon high-risk features. Some reports suggest that tumors <5 mm are less likely to have high-risk features than those >5 mm and may be managed conservatively. Our objective was to compare the clinical and histological characteristics of small (<5 mm) to large PTMC (>5 mm).

From 2002 to 2011, data were collected prospectively from 1459 sequential patients undergoing thyroid surgery at a single institution. Among these patients, 132 (9%) were found to have PTMC of <1 cm without the presence of a macrocarcinoma (>1 cm). We performed a retrospective analysis of these PTMC cases. Fisher's Exact test was used. Statistical significance was set at p<0.05 a priori.

Overall, 75 cases (57%) revealed small PTMC, 84 (64%) were aged >45, and 105 (80%) were women. Small PTMCs were identified more frequently than large PTMCs in older patients (63% vs. 37%) and female patients (61% vs. 39%), but this did not reach significance (p=0.07 and 0.09, respectively). High-risk features were assessed, including multifocality in 38 cases (29%), bilaterality in 8 cases (6%), extrathyroidal cancer extension (ETE) in 6 cases (5%), lymph node metastases in 9 cases (7%), and distant metastases in 1 case (<1%). A relationship between larger cancers and high-risk features was seen only with ETE. Six of 57 large PTMC (11%), but none of 75 small PTMC (0%) had ETE (p<0.01). Lymph node metastases were present in both small PTMC (5/9 cases) and large PTMC (4/9 cases). In the patients with LN metastases, 3/9 had zero high-risk features, 2/9 had a single high-risk feature, and 4/9 had two high-risk features. Extrathyroidal extension was seen in only 2 of the 9 patients with LN metastases. The single case of distant metastases was diagnosed in a 3-mm PTMC.

Diagnosis of PTMC is common after thyroid surgery. However, neither cancer size <5 mm nor the absence of high-risk features excluded the possibility of synchronous lymph node metastases. The significance of high-risk features in PTMC requires further study to identify the optimal management of this common endocrine malignancy.

1 Otolaryngology-Head & Neck Surgery, Oregon Health & Science University, Portland, OR 2 Knight Cancer Institute, Oregon Health & Science University, Portland, OR 3 Public Health & Preventive Medicine, Oregon Health & Science University, Portland, OR 4 Radiation Oncology, Oregon Health & Science University, Portland, OR Poster 70 NOMOGRAM PREDICTIVE OF 10-YEAR CAUSE-SPECIFIC MORTALITY IN DIFFERENTIATED THYROID CANCER

Thyroid Cancer Thursday Poster Clinical

The application of appropriate treatment for differentiated thyroid cancer (DTC), including extent of surgery and adjuvant therapy, is predicated on accurate patient risk stratification. Although risk factors for mortality from DTC have been well described on the population level, they have not been unified into a single algorithm to predict individual risk. This study aimed to develop a nomogram to estimate 10-year cause-specific mortality in well-to-poorly DTC.

A historical cohort of 9,666 patients with DTC recorded in the SEER National Cancer Registry from 1985 to 1995 was used to identify and quantify the most clinically relevant predictors of 10-year thyroid cancer-specific mortality. Competing risk regression was used for model selection and nomogram development. The predictive accuracy of the nomogram was internally validated using bootstrapping methods and assessed using the area under the receiver operating characteristic curve (AUC).

Ten-year cause-specific mortality was 3.7%. Significant predictors of mortality included age, gender, extracapsular extension, tumor size, nodal status, distant metastasis, and histology. The nomogram successfully estimated an individualized risk of mortality from DTC by assigning relative weights to each of these risk factors. Model discrimination and calibration were found to be very good.

This nomogram is the first prognostic model developed to predict the likelihood of thyroid cancer mortality for an individual patient with DTC. More accurate patient risk stratification using the nomogram has practical applications for clinical care and research.

1 Department of General Surgery, Vanderbilt Univ Med Ctr, Nashville, TN 2 Department of Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI 3 Department of Surgery, University of Miami Miller School of Medicine, Miami, FL Poster 72 CANCER AFTER THYROIDECTOMY: A MULTI-INSTITUTIONAL EXPERIENCE WITH 1,523 PATIENTS

Thyroid Cancer Thursday Poster Clinical

Incidental thyroid cancer (iTC) in patients treated operatively for benign thyroid disease has been historically low (<5%). Previous series have not specifically addressed iTC incidence in both euthyroid and hyperthyroid patients. This study examined the iTC frequency in patients referred for removal of benign thyroid disease in a multi-institutional surgical series.

Approximately 2551 patients underwent thyroidectomy at three tertiary-care institutions. Indeterminate/malignant diagnosis by FNA was excluded (n=1028). Cases of iTC were compared among 1523 patients with Graves' (G, n=264), nodular goiter (MNG, n=1095), and toxic nodular goiter (TG, n=164). Fisher's Exact and Chi-squared tests, ANOVA, and nonparametric t-tests were used.

Overall, 243 iTCs were recorded (15.9%): G (16/264, 6.1%), MNG (191/1095, 17.4%), and TG (30/164, 18.3%). iTC rates were significantly different between these groups (p<0.01) and significantly higher in MNG and TG vs. G (17.4% and 18.3% vs. 6.1%, respectively; p<0.01). No association was noted with iTC for gender, age, or performance of preoperative FNA (p>0.05). Mean iTC size was 1.05 cm (46%>0.5 cm and 39%>1 cm). Overall, 287 patients had lymphocytic thyroiditis (19%), but no significant association with iTC was found (p=0.42). Most patients underwent total thyroidectomy (80%) followed by lobectomy/other.

These data confirm higher-than-expected iTC rates compared to historical controls in the largest multi-institutional surgical series to date (15.9% vs. 3–5%). The percentage of iTC cases in nodular goiter or toxic nodular goiter patients was significantly higher than the iTC rate in Graves'. Thyroiditis was not associated with iTC. This study provides evidence that in patients referred for thyroidectomy, the best surgical approach to non-Graves' toxic goiter is a total or near-total thyroidectomy. These data also suggest that similar treatment may be prudent for nodular goiters regardless of preoperative FNA results.

1 Endocrinology, Mayo Clinic, Rochester, MN 2 Radiology, Mayo Clinic, Rochester, MN Poster 73 ROLE OF ULTRASOUND-GUIDED PERCUTANEOUS ETHANOL ABLATION (UPEA) IN THE MANAGEMENT OF SELECTED NECK NODAL METASTASES (NNM) IN SEVEN CASES OF SPORADIC MEDULLARY THYROID CARCINOMA (MTC)

Thyroid Cancer Thursday Poster Clinical

UPEA can effectively manage NNM in papillary thyroid carcinoma (JCEM 96: 2717–20, 2011). In 1991, we used UPEA to treat two left-central compartment NNM (9-mm and 1.1-cm diameter) in a psychiatrist, who had earlier undergone three neck surgeries with resulting transection of his right recurrent laryngeal nerve, and was now facing possible tracheostomy. His ablated MTC nodes disappeared on high-resolution sonography within 10 months and did not recur after 21 years of follow-up. In 1994, we used UPEA to treat hepatic metastases and selected NNM in a second MTC patient. Since 2001, we have ablated NNM with ultrasound-guided injections of 95% ethanol in another five MTC patients.

In this report, we describe these seven patients, their UPEA treatments, and their final status. At presentation, pTNM stages were II in one, IVA in 3, and IVC in 3. Pre-UPEA serum calcitonin levels were universally raised (median 619 pg/mL; range 24–35,000). UPEA was performed on selected NNM after a mean of eight years since initial presentation (range 4–16). Mean age of patients at UPEA was 50 years (range 38–72). Nine recurrent nodes (largest mean diameter 13 mm; range 10–18) were initially injected with a mean of 0.8 cc (range 0.35–2.3 cc) of 95% ethanol. Patients were followed-up for a median of 10 years (range 4–21).

At latest follow-up, all ablated NNM had shrunk and had no Doppler flow; 4/7 (57%) had disappeared on sonography. No patient after UPEA developed hoarseness. No ablated node re-grew, requiring further treatment. Four patients progressed locally. Two required neck re-exploration for NNM at different locations from UPEA sites; two had UPEA, avoiding re-exploration. In the two patients with localized disease (T2-4 N1M0), no further neck intervention occurred after 10 years follow-up, and calcitonin levels fell significantly. In the seven patients, nine neck re-explorations were avoided, and >346,000 dollars were saved. All seven patients are surviving after a mean of 19 years (range 14–33) since initial thyroidectomy.

UPEA will not usually influence the ultimate outcome in MTC, but it can effectively, harmlessly, and inexpensively eliminate selected NNM, avoiding the expense and morbidity of further neck surgery.

1 Metabolism, Endocrinology and Diabetes, University of Michigan, Ann Arbor, MI 2 Nuclear Medicine, University of Michigan, Ann Arbor, MI 3 Biostatistics, University of Michigan, Ann Arbor, MI Poster 74 FACTORS THAT INFLUENCE RADIOACTIVE IODINE USE FOR THYROID CANCER

Thyroid Cancer Thursday Poster Clinical

There is a variation in the use of radioactive iodine as treatment for thyroid cancer, and the factors involved in physician decision making remain unknown.

We surveyed physicians involved in thyroid cancer management from 251 hospitals. Respondents were asked to rate the factors important in influencing whether a thyroid cancer patient receives radioactive iodine. Multivariable analyses controlling for physician age, gender, specialty, case volume, and whether they administer radioactive iodine were performed.

The survey response rate was 63% (534/853). Extent of disease, adequacy of surgical resection, patients' willingness to receive radioactive iodine, and patients' age were the most important factors influencing recommendations regarding radioactive iodine to patients with thyroid cancer. Interestingly, both physicians' and patients' worry about death from thyroid cancer was also important in determining radioactive iodine use, especially for physicians with fewer thyroid cancer cases per year. In multivariable analyses, lower physician thyroid cancer patient volume was associated with a greater importance placed on patients' (p-<0.001) and physicians' worry about death (p=0.016). Other factors with higher importance to physicians with lower thyroid cancer patient volume include accepted standard at affiliated hospital (p=0.020), beliefs about radioactive iodine expressed by colleagues co-managing patients (p=0.003), and patient distance from the nearest facility administering radioactive iodine (p=0.012).

In addition to extent of disease and adequacy of surgical resection, physicians place importance on physician and patient worry about death from thyroid cancer when deciding whether to treat a patient with radioactive iodine. The factors important to physician decision making differ based on physician thyroid cancer case volume, with worry about death being more important for low-volume physicians. As the mortality from thyroid cancer is low, the importance placed on death in decision making may be unwarranted.

1 Nuclear Medicine Department, Peking Union Medical College Hospital, Beijing, China 2 Oncology Department, Qingdao University Medical College Affiliated Hospital, Qingdao, China 3 General Surgery Department, Peking Union Medical College Hospital, Beijing, China Poster 75 INVESTIGATION OF AGGRESSIVENESS OF DIFFERENTIATED THYROID CARCINOMA IN PEDIATRICS AND ADOLESCENTS

Thyroid Cancer Thursday Poster Clinical

Clinical features of differentiated thyroid carcinoma (DTC) in pediatric and adolescent patients differed from that of adult patients. Study concerning clinical and pathological characteristics of this population would make a great contribution upon clinical management of pediatric and adolescent DTC.

A total of 32 DTC cases (≤18 years old) were enrolled in this study. They were stratified according to different age and gender. Aggressive features of these patients were analyzed.

Bilateral, multifocal, as well as extrathyroid invasion was more often in patients younger than 12-years old. Patients with bilateral tumor invasion, lymph node metastasis, or distant metastasis were younger than those without (p=0.042, 0.027, and 0.031, respectively). The aggressive features were similar between male and female gender in younger patients, while it appeared to be more aggressive in male adolescents. Papillary pattern, bilateral invasion, and multifoci were related to lymph node metastasis (p=0.000, 0.007, 0.001, respectively). Compared to patients received initial total thyroidectomy, a higher rate of distant metastasis was observed in those who did not (47.37% vs. 92.31%, p=0.011).

Pediatric and adolescent DTC presents with a more aggressive pattern, especially in male and patients younger than 12-years old. More attention should be paid on DTC patients with above features, and total thyroidectomy should be applied to reduce the risk of distant metastasis.

OPEN IN VIEWER

POSTER 75.

Investigation of aggressiveness of differentiated thyroid carcinoma in pediatrics and adolescents.

1 Surgery, Jersey Shore University Medical Center, Neptune, NJ 2 Internal Medicine, Division of Endocrinology, Jersey Shore University Medical Center, Neptune, NJ 3 Office of Clinical Research, Jersey Shore University Medical Center, Neptune, NJ Poster 80 INITIAL MODES OF DETECTION OF THYROID NODULES IN SURGICAL PATIENTS IN CORRELATION TO FAMILY HISTORY, RADIATION EXPOSURE, AND FINAL PATHOLOGICAL DIAGNOSIS

Thyroid Cancer Thursday Poster Clinical

The rate of thyroid cancer has been increasing, which has also been attributed to improved detection. The aim of this study was to evaluate the initial mode of thyroid nodules detection in patients who underwent thyroidectomies, to correlate that with the pathology, especially differentiated thyroid carcinoma (DTC).

Five hundred and four consecutive patients underwent thyroidectomy from 2007 to 2011. Charts, family history, history of radiation exposure, surgery, and pathology reports were analyzed.

Of the 504 patients (430 women [85.3%], 74 men [14.7%]), 195 (38.7%) had DTC (PTC-176 [90.3%], FTC-6 [3%], HCC-9 [4.6%], and MTC-4 [2.1%]). Self-examination (96 patients [19.05%]) and examination by their primary-care physician (PCP) (96 patients [19.05%]) were the most common modes of detection. Twenty-eight (29%) of the self-examined patients and 33 (34.4%) of examined by PCP had DTC. Endocrinologists and gynecologists discovered nodules in 73 (14.5%) patients. CT, MRI, PET, and CXR (excluding US) detected nodules in 70 (13.9%) patients. Neck US (excluding thyroid) incidentally discovered nodules in 97 (19.2%), and 46 (47.4%) of them had DTC. Of the same 97 patients, 20 (3.97%) were discovered by carotid US, they had the highest rate of DTC (13/20=65% patients [2.6% of all DTC]). Together all imaging studies, 79 of 195 (40.5%) patients had DTC. The largest nodules were discovered by a third-party observer (∼3.76 cm), self-examination (∼2.55 cm), by gynecologist (∼2.54 cm), and by endocrinologist (∼1.69 cm), and they have a relatively high rate of DTC (16/33=48.5%). Family history of DTC in the first-degree relatives 29/504=5.75%, 16(55%) of them developed DTC (PTC-13, FTC-1, and MTC-2); in the 2nd-degree relatives 14/504=2.8%, 8 of them (57%) developed PTC. Radiation exposure were detected in 42 patients (8%), and 14 of them (33%) had DTC (2.78% of all DTC).

Self-examination and examination by the PCP are the most common mode of initial detection of thyroid nodules. Nodules incidentally found by imaging studies, especially carotid US, have a higher rate of DTC. Endocrinologists found DTC in earlier stages. Family history of DTC in the 2nd-degree relatives as important as in the 1st degree, those patients should have low threshold for surgery.

1 Northern Centre for Cancer Care, Freeman Hospital, Newcastle Upon Tyne, United Kingdom 2 Northern Centre for Cancer Care, Freeman Hospital, Newcastle Upon Tyne, United Kingdom 3 Northern Centre for Cancer Care, Freeman Hospital, Newcastle Upon Tyne, United Kingdom 4 Northern Centre for Cancer Care, Freeman Hospital, Newcastle Upon Tyne, United Kingdom Poster 82 TOMOTHERAPY AND FDG -PET-CT-BASED DOSE- ESCALATED INTENSITY-MODULATED IMAGE-GUIDED RADIOTHERAPY (IM IGRT) FOR LOCOREGIONAL RECURRENCE OF DIFFERENTIATED THYROID CANCER—PRELIMINARY EXPERIENCE

Thyroid Cancer Thursday Poster Clinical

Introduction differentiated thyroid cancer (DTC) incidence is increasing worldwide. External beam radiotherapy (RT) is recommended in locoregional recurrence or locally advanced disease, when complete resection is not possible and/or when tumors do not concentrate radioactive iodine (RAI). Conventional radiotherapy techniques often cannot deliver high curative doses to all parts of the thyroid tumor. This is because the tumor-bearing area lies closely applied to normal organs at risk (OARs), particularly the spinal cord, parotids, constrictor muscles, esophagus, and larynx, where the radiotherapy dose must be kept within safe tolerance limits of the organs, which is well below the tumoricidal dose. Intensity-modulated RT (IMRT) where differential doses can be given to different parts of the tumor and normal organs has been recommended for thyroid cancer. Helical tomotherapy (HT) is a linear accelerator with a built-in CT scanner and can deliver superior quality of IMRT with image guidance (image-guided radiotherapy), in which daily pretreatment CT scan allows more accurate localization of the tumor target and avoids normal structures throughout a long course (5–6 weeks) of daily radiotherapy. FDG-PET CT scans, which are often used to stage recurrent and radioiodine refractory DTC, also delineate the most metabolically and biologically active part within the tumor with increased tumor cell burden, which can be radioresistant to standard doses. Focal higher dose of radiotherapy to these PET-avid areas with IM-IGRT is increasingly used in head and neck and other cancers in an attempt to increase local control and cure while safeguarding OARs.

We present our preliminary experience of safe dose escalation using PET-based delineation and HT in DTC.

HT has dosimetric advantages with less early and late side effects despite dose escalation PET-CT allows better coverage and dose escalation with HT, which may improve local tumor control.

To our knowledge, this is possibly the first report of this kind and merits further study.

1 Northern Centre for Cancer Care, Freeman Hospital, Newcastle Upon Tyne, United Kingdom Poster 83 DOSE-DENSE WEEKLY TAXOL AND TOMOTHERAPY FOR ANAPLASTIC THYROID CANCER

Thyroid Cancer Thursday Poster Clinical

Anaplastic thyroid cancers are rare and have a dismal prognosis. While surgery for limited disease has the best outcome, majority present late, and neoadjuvant adjuvant, definitive, and palliative chemo-/radiotherapy is usually associated with a median survival of between 3 and 12 months. In recent years, chemotherapy with Taxol and high-dose radiotherapy has been recommended. Because of the very short doubling time of the tumor cells, dose-dense chemotherapy with weekly Taxol is an attractive idea.

We have recently treated 3 anaplastic thyroid cancers with induction of weekly Taxol 80 mg per sq meter body surface area for 2 to 3 courses followed by 40 mg per sq meter weekly with tomotherapy-based high-dose intensity-modulated radiotherapy giving 66 Gy in 30 fractions to the tumor and 54 Gy to uninvolved nodal areas in 2 patients.

This is a preliminary finding, but the tolerance is better than other chemotherapy regimes, and the early responses are quite encouraging. Most importantly, patients have been able to finish their 6-week-long course of radiotherapy, which quite often is not possible. One patient required temporary NG feeding, and his histology was poorly differentiated squamous cell carcinoma incompletely resected, but has local control in the neck.

While it is not curative treatment, it would appear in our preliminary experience that weekly Taxol with high-dose tomotherapy-based intensity-modulated radiotherapy might be an option, which merits further study for anaplastic thyroid cancer.

1 Internal Medicine, Asan Medical Center, Seoul, Republic of Korea 2 Health Screening & Promotion Center, Asan Medical Center, Seoul, Republic of Korea 3 Pathology, Asan Medical Center, Seoul, Republic of Korea 4 Surgery, Asan Medical Center, Seoul, Republic of Korea Poster 84 OBESITY AS A RISK FACTOR FOR THYROID CANCER

Thyroid Cancer Thursday Poster Clinical

Obesity has been associated with increased incidence of cancers of the esophagus, colon, kidney, breast, melanoma, rectum, and gall bladder. There have been few studies on the relationship between obesity and thyroid cancer. We conducted this study to evaluate the association between obesity and incidence of thyroid cancer.

We recruited data of 16,481 (8,741 men and 7,740 women) subjects who were free of prior or family history of thyroid disease (thyroid dysfunction, nodule, cancer, and surgery), and who underwent thyroid ultrasonography from 2007 to 2008 in the Health Screening and Promotion Center of Asan Medical Center, Seoul, Korea. We retrospectively reviewed the medical records and analyzed risk factors predicting presence of thyroid cancer separately in men and women.

Of the 16,481 subjects, thyroid cancers were diagnosed in 227 (100 men and 127 women) patients, which were confirmed by surgery. In men, there was no significant association between the body–mass index (BMI) and incidence of thyroid cancer. In women, thyroid cancer incidence was significantly associated with BMI (per 5 kg/m² increase) (OR=1.63, 95% CI: 1.20–2.18, p=0.001), after adjustment of age, smoking, TSH values. We also found that thyroid cancer was negatively associated with tobacco smoking in women (OR 0.29, 95% CI: 0.07–0.78, p=0.036).

Obesity was an independent risk factor for thyroid cancer in women when evaluated in a routine health check-up. Not only increased detection but also true increase of incidence caused by obesity might be responsible for the increasing incidence of thyroid cancer over recent decades.

1 Medicine (Endocrinology), McGill University, Montreal, QC, Canada 2 Surgery, McGill University, Montreal, QC, Canada 3 Otolaryngology, McGill University, Montreal, QC, Canada Poster 86 BACKGROUND LYMPHOCYTIC THYROIDITIS PREDICTS BETTER OUTCOMES ONLY IN OLDER PTC PATIENTS: OUR EXPERIENCE WITH 475 CASES

Thyroid Cancer Thursday Poster Clinical

Background lymphocytic thyroiditis (LT) has been reported in 0.5–38% of papillary thyroid cancer (PTC) patients. Several, but not all, reports have shown this association to affect favorably PTC prognosis. The idea is that thyroid follicular cells in LT express both FAS (apoptosis antigen 1) and the FAS ligand, hence triggering FAS-mediated apoptosis resulting in destruction of the thyroid benign and tumor tissue. A lower prevalence of BRAF mutation has also been reported in LT patients with PTC.

We conducted a retrospective review of 475 consecutive PTC patients treated at the McGill University Health Center. Tumor size, vascular or capsular invasion, multifocality, extrathyroidal extension, lymph node metastases, distant metastases, background LT, status of the disease at 6–12-month post-therapy, and survival were recorded.

Background LT was present in 35% of PTC specimen. Background LT was associated with higher percentage of stage I disease and fewer disease persistence. After stratification by age, background LT association with a reduced frequency of disease persistence was present only in patients over 45 years of age. In patients younger than 45 years, the presence of LT was associated with higher rate of extrathyroidal extension, capsular invasion, and multifocality. Disease multifocality in the presence of chronic lymphocytic thyroiditis has been previously reported.

The potential protective effect of LT in PTC seems to be particularly relevant in older patients.

1 Nuclear Medicine and Endocrine Oncology Service, Institut Gustave Roussy, Villejuif, France 2 Biostatistic and Epidemiology Service, Institut Gustave Roussy, Villejuif, France 3 Pharmacology and Drug Analysis Department, Institut Gustave Roussy, Villejuif, France 4 Department of Oncology, University of Alberta, Edmonton, AB, Canada 5 Department of Ambulatory Care, Institut Gustave Roussy, Villejuif, France Poster 88 MUSCULAR MASS AS AN INDEPENDENT FACTOR OF VANDETANIB PLASMA CONCENTRATION AND DOSE-LIMITING TOXICITY IN PATIENTS TREATED WITH VANDETANIB FOR ADVANCED MEDULLARY THYROID CARCINOMA

Thyroid Cancer Thursday Poster Clinical

Low muscular mass (MM) has been associated with dose-limiting toxicity in patients with solid tumors treated with chemotherapy and with renal cell carcinoma treated with sorafenib. The aim of this study was to assess the association between body composition, toxicity, and plasma level of vandetanib in patients treated for metastatic or locally advanced medullary thyroid carcinoma.

Thirty-two patients (24 men and 8 women, mean age of 54 years) treated with vandetanib (300 mg/d) were included (ZETA trial). Plasma vandetanib concentration was measured using a reverse-phase high-performance liquid chromatography coupled with tandem-mass spectrometry. Cross-sectional areas (cm²) of visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and MM were assessed by computed tomography (CT) imaging at 0, 3, 6, and 12 months of treatment and were indexed for height (cm²/m²). Significant toxicities, defined as requiring a dose reduction or treatment withdrawal, were collected.

A total of 14 patients (44%) [8 men (33%) and 6 women (75%)] had significant toxicity during vandetanib treatment. The most frequent toxicities were asthenia grade 3 (36%), prolongation of the QTc interval (25%), and cutaneous symptoms (11%). In women, no significant relationship was found between body composition, vandetanibemia, and toxicity. In men, a significant lower mean MM (37 vs. 45 cm²/m²; p=0.007) and higher mean vandetanib plasma concentration (1006 vs. 698 ng/mL; p=0.04) were associated with toxicity. When all patients were analyzed together (n=32), patients with significant toxicities had lower mean MM (37 vs. 44 cm²/m², p=0.003) and a higher mean vandetanib plasma concentration (1091 vs. 739 ng/mL, p=0.03). Furthermore, patients with the highest plasma concentrations (defined as ≥20% of median) had significantly lower MM (37 vs. 45 cm²/m²; p=0.003). Correlations with the body–mass index, VAT, and SAT were not significant in any studied group.

Our study is the first to highlight the importance of body composition and plasma vandetanib concentration assessments while prescribing vandetanib.

1 Nuclear Medicine and Endocrine Oncology Service, Institut Gustave Roussy, Villejuif, France 2 Biostatistic and Epidemiology Service, Institut Gustave Roussy, Villejuif, France 3 Department of Oncology, University of Alberta, Villejuif, France 4 Department of Ambulatory Care, Institut Gustave Roussy, Villejuif, France Poster 89 EFFECTS OF VANDETANIB ON BODY COMPOSITION IN PATIENTS WITH ADVANCED MEDULLARY THYROID CARCINOMA (MTC): RESULTS FROM A PLACEBO-CONTROLLED STUDY

Thyroid Cancer Thursday Poster Clinical

Muscle (MT) and adipose tissue (AT) share common intracellular pathways with tumor tissue; thus, it is not surprising to observe metabolic consequences with targeted therapies. The aim of the study was to assess the effects of vandetanib, a tyrosine kinase inhibitor (TKI) that demonstrated efficacy for the treatment of advanced MTC on MT and AT.

Thirty-three patients (25 men and 8 women, mean age of 54 years) with metastatic MTC received vandetanib 300 mg/d (n=23) or placebo (n=10) in the setting of the ZETA study. Cross-sectional areas (cm²) of visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and MT were assessed by computed tomography imaging at 3rd lumbar vertebra and were indexed for height (cm²/m²).

At 3 months, compared to baseline, patients treated with vandetanib gained 1.5 kg, 1.3 cm²/m² of MT, 5.1 cm²/m² of VAT, and 4.5 cm²/m² of SAT. In contrast, patients under placebo lost 1.5 kg (p=0.02), 1.0 cm²/m² of MT (p=0.009), 5.5 cm²/m² of SAT (p=0.004) and gained significantly less VAT (0.6 cm²/m²) (p=0.02). At 12 months, compared to baseline, patients treated with vandetanib gained 2 kg (NS), lost 0.3 cm²/m² MT (NS), gained 4.5 cm²/m² of VAT (95% CI, 0.4 to 8.6) and 9.8 cm²/m² of SAT (95% CI, 3.4 to 16.1). A significant decrease of calcitonin (defined as ≤50% compared to baseline) was associated with higher weight (p=0.01), VAT (p=0.01), and total adipose tissue (p=0.02).

Beyond its proved efficacy in MTC treatment, and despite common intracellular pathways, vandetanib is the only studied TKI to preserve MT and to restore AT. Further research is needed to explore whether the relationship between changes of VAT and vandetanib treatment results from a direct metabolic effect of vandetanib or is a consequence of biochemical tumor control.

1 Medicine, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada 2 Otolaryngology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada 3 Diagnostic Imaging, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada 4 Radiation Oncology, Dalhousie University, Halifax, NS, Canada 5 Otolaryngology-Head and Neck Surgery, University of Ottawa, Ottawa, ON, Canada 6 Economics, University of New Brunswick, Fredericton, NB, Canada Poster 90 THYROID CANCER STAGE AT PRESENTATION IS MORE ADVANCED IN PATIENTS WITH LOWER SOCIOECONOMIC STATUS

Thyroid Cancer Thursday Poster Clinical

Thyroid cancer is increasingly diagnosed in North America. Some studies have suggested a higher rate of thyroid cancer in patients with higher insurance rate and higher socioeconomic status (SES). However, it is not known if the stage of thyroid cancer at diagnosis varies with SES. We studied the relation between SES and thyroid cancer stage at presentation in a large thyroid cancer database.

We used data from South-Western Ontario from the Canadian Thyroid Cancer Consortium, a large thyroid cancer registry. We included patients who presented between January 1998 and December 2010 with documented thyroid cancer. We determined thyroid cancer status, sex, and age at presentation, and determined AJCC stage (I, II, III, IV/A, and IV/B or C). Data from the Canadian Census of Population for the years 1996, 2001, and 2006 were used to determine SES based on the individual postal code. A logistic regression model (ordered logit) was used to determine odds ratios of the thyroid cancer stage related to SES, using highest income as denominator.

We included 1563 patients form South-Western Ontario, and were able to assign census data to 1334 cases. Odds ratios (95% confidence intervals) were 1.718 (1.23–2.39) for lowest SES quintile, 2.077 (1.62–2.66) for male sex versus female sex, and 1.010 (1.00–1.02) for age. Time-trend analysis demonstrated an odds ratio of 0.962 (0.93–1.00) compared to the base year.

The pattern in the income quintile estimates clearly indicates that lower average household income is associated with a more advanced stage of thyroid cancer at diagnosis. Advanced age is associated with more advanced stage at diagnosis. Compared to the baseline year, the time-trend analysis indicates that the odds of being diagnosed at a more advanced stage decline by ∼4% per year. Thus, thyroid cancer is being diagnosed earlier over time.

1 Endocrinology, Complejo Hospitalario de Toledo, Toledo, Spain 2 Pathology, Complejo Hospitalario de Toledo, Toledo, Spain 3 Surgery, Complejo Hospitalario de Toledo, Toledo, Spain Poster 91 BRAF MUTATION IN PAPILLARY THYROID CARCINOMA IS ASSOCIATED WITH POOR CLINICOPATHOLOGICAL FEATURES

Thyroid Cancer Thursday Poster Clinical

Thyroid carcinoma is the most common endocrine malignancy. BRAF V600E point mutation is the most frequent detected genetic change in papillary thyroid carcinomas (PTC). There are some discrepancies regarding its relationship with clinicopathological parameters of poor outcome.

The objective of the study was to investigate the relationship of clinicopathological features of PTC with BRAF mutation.

We analyzed 132 consecutive patients (80.4% female, mean follow-up 41.2±31.5 months, mean age at diagnosis 46.2±15.7 years) with pathological diagnosis of PTC. DNA was extracted from paraffin-embebbed tissue sections, and V600E mutations were detected by HRM, followed by sequencing confirmation. Demographic, clinical, and pathologic characteristics were analyzed. Univariate (Chi-Squared and Student t-test) and multivariate analysis were realized. For statistical processing, we used SPSS version 15.0.

BRAF (V600E) was detected in 49.2% of the study group. The histologic subtype-specific prevalence of mutation was significantly different between BRAF (V600E)-positive and wild-type patients (p<0.05) (see Table). BRAF (V600E) mutation was associated with age (p<0.05), extrathyroidal invasion (p<0.05), and with tumors of greater size or locally invasive (T1+T2 vs. T3) (p<0.05). There were no associations with sex, tumor size, multicentricity, or lymph node metastasis. BRAF (V600E) was negatively associated with the presence of distant metastasis in our group (p<0.05). By multivariate analysis, only age (OR 1.04; CI 95% 1.0–1.1, p<0.05) and extrathyroidal invasion (OR 4.5; CI 95% 1.2–15.5, p<0.05) were independently associated with the presence of BRAF (V600E) mutation.

Our data confirm that BRAF (V600E) mutation in this European group occurred in less than half PTC population and was associated with some histological subtypes (classical) of PTC and with local invasive growth cancers. This work was supported by the grant PI-2009/16 from Sanitary Research Foundation of Castilla-La Mancha (FISCAM).

1 Endocrinology, General Hospital Chieti, Chieti, Italy 2 Surgery, Stella Maris, San Benedetto AP, Italy 3 Pathology, Johns Hopkins, Baltimore, MD Poster 99 ABOUT ENCAPSULATED PAPILLARY THYROID CARCINOMAS (EPTC)

Thyroid Cancer Thursday Poster Clinical

The evolutionary behavior of differentiated thyroid carcinoma (DTC) seems to correlate with the morphological appearance on the one hand, but above all, in relation with the tumor capsule infiltration (Evans HL). In fact, in the papillary thyroid carcinoma, capsular invasion without the overcoming of this is related to a good prognosis, while the presence of capsular invasion in encapsulated follicular carcinoma is associated to a bad prognosis (Evans HL).

We reported our observations about our surgical series related to the pathology of EPTC, starting from a description of a case of a young woman.

We have observed a 25-year-old woman who discovered a thyroid nodule of 13-mm diameter in 2003. It increased along the scale of 8 years till 40-mm diameter. At the beginning of 2012, it was decided a surgical resection of the nodule. Histological features showed encapsulated papillary carcinoma. Enlarged lymph nodes were not observed nor alterations in the remaining thyroid parenchima. Therefore, it was decided not to reoperate In a subsequent intervention casistic of 150 thyroidectomy, the percentage of thyroid carcinomas was 14%, and 4 (20%) were encapsulated papillary carcinomas, with a diameter ranging between 30 and 40 mm, and in all our behavior was conservative surgery (hemithyroidectomy). In any case, we were sure about the integrity of the lymphonodes and the remaining lobe with previous and intraoperative ultrasonography, with the probe adhering and in contact with the lobe.

In our series, we followed the Evans and Rosai criteria to classify DTC; consequently, in EPC, we suggest a conservative surgery considering a new technique of intraoperative ultrasonography that ensures the integrity of the remaining thyroid tissue. Finally, with regard to the EPC, likewise follicular neoplasm classification, it could be proposed the definition of papillary adenoma instead papillary carcinoma when it is encapsulated, reserving the definition of PTC only to those that exceed the capsule.

1 Hematology/Medical Oncology, Emory University, Atlanta, GA 2 Biostatistics, Emory University, Atlanta, GA 3 Head and Neck Surgery, Emory University, Atlanta, GA 4 Medicine/Endocrinology, Emory University, Atlanta, GA 5 Novartis Oncology, Novartis, East Hanover, NJ Poster 100 TRANSLATIONAL STUDY EVALUATING THE EFFICACY OF EVEROLIMUS AND PASIREOTIDE (SOM230) IN THYROID CANCER

Thyroid Cancer Thursday Poster Translational

Thyroid cancer is the most common endocrine cancer worldwide with increasing number of patients with incurable metastatic disease. Newer treatment approaches are warranted to improve clinical outcome. We evaluated the efficacy of everolimus, an mTOR inhibitor, and pasireotide (SOM230), a somatostatin analog, using preclinical tumor xenograft. We also report the preliminary result of an ongoing phase II clinical trial of everolimus and pasireotide in thyroid cancer.

In vivo efficacy of everolimus and pasireotide was tested in a xenograft model of thyroid cancer using BCPAP and TPC-1 cell lines. Tumor-bearing mice were treated with vehicle, everolimus (oral), or pasireotide LAR (subcut). Tumor growth inhibition was assessed after 28 days on treatment. In a phase II clinical trial, subjects≥18 years, ECOG PS 0–2, with radiorefractory differentiated or medullary thyroid cancer, adequate organ function, were enrolled and randomized to receive pasireotide LAR (60 mg once every 4 weeks), everolimus (10 mg once daily continuously), or the combination. Using a Simon's 2-stage design, each arm will enroll 28 patients to assess the response rate of P0=5% vs. P1=15%, power=80%, and α=0.05. Patients were treated until disease progression by the RECIST criteria as assessed once every 2 cycles (cycle=28 days) or with development of intolerable toxicity.

Everolimus and pasireotide displayed potent inhibition of TPC1 and BCPAP thyroid cancer xenograft growth in vivo without inducing significant toxicity. This result has been successfully translated into a phase II efficacy clinical study in advanced thyroid cancer (NCT01270321) that has enrolled 13 patients to date: M/F (6/7); histology: medullary (4), differentiated (9). Eight patients achieved a best response on treatment of stable disease, 3 with progression, and 2 still indeterminate. Median duration on therapy was 168 days (range: 14–539 days). Salient adverse events include fatigue, anemia, stomatitis, elevated glucose, cholesterol, and triglyceride.

Everolimus and pasireotide showed efficacy in a preclinical model with successful translation into early clinical testing. These agents may provide additional therapeutic options for thyroid cancer patients in the future.

OPEN IN VIEWER

POSTER 100.

Tumor growth curves in tumor-bearing mice treated with everolimus/vehicle (top left); pasireotide/vehicle (lower left); animal weight during treatment with vehicle, everolimus, or pasireotide (lower right); harvested tumor weights at the end of treatment (upper right).

1 Genetic and Molecular and Cellular Physiology Center_ CNRS 5534 UMR, Lyon 1 University, Villeurbanne, France 2 Medical Unit of Molecular Oncology and Transfer, Hospices Civils of Lyon, Lyon, France Poster 103 IDENTIFYING SPECIFIC FUNCTIONS AND PATHWAYS AFFECTED BY THYROID HORMONE RECEPTOR TRa1 IN THE MURINE INTESTINAL EPITHELIUM

Thyroid Hormone Action Thursday Poster Basic

It has been previously demonstrated that specific TRa1 overexpression in murine intestinal epithelium accelerates tumorigenesis in the background of the constitutively activated WNT pathway. The objective was to elucidate which molecular programs are specifically affected by TRa1 during intestinal tumorigenesis.

Samples were collected from i) wild-type mice intestine (WT), ii) tumoral lesions of APC+/1638N mice with a constitutively activated WNT pathway (AT), and iii) tumoral lesions of APC+/1638N mice overexpressing TRa1 in intestinal epithelium vil-TRa1/Apc+/1638N (TRAT). Transcriptomic analyses were performed using Mouse GE 4x44Kv2 Microarray (Agilent) to identify genes associated with the tumorigenic AT_WT sequence and those associated with the tumorigenic TRAT_WT sequence. The in vivo biological effects of TRa1 overexpression were further bioinformatically examined by applying the Ingenuity® Pathway Analysis (IPA) and Gene Set Enrichment Analysis (GSEA).

The most significant functions specifically associated with the TRAT_WT sequence, as compared to the AT_WT sequence, were organogenesis, morphogenesis, and tissue development, in particular in the gastrointestinal tract. Expectedly affected in the AT_WT sequence, the WNT pathway was significantly further affected in the TRAT_WT sequence. TRAT-specific alterations of the WNT pathway included multiple regulations of WNT activators and inhibitors. HNF4A target genes were found as specifically altered in the TRAT_WT sequence (stimulation vs. inhibition in AT_WT sequence). Additionally, significant over-representation of genes in the NOTCH pathway was disclosed in the TRAT_WT sequence by GSEA.

Specific functions and pathways are impacted by TRa1 overexpression during intestinal tumorigenesis. They include gastrointestinal development, a function strongly reminiscent of the well-known role played by TRa1 during intestinal organogenesis and histogenesis. The WNT pathway is specifically altered by TRa1 as well as other pathways involved in colorectal carcinogenesis, such as HNF4A and NOTCH.

1 Medicine, Imperial College London, London, United Kingdom 2 Pathology, Imperial College Healthcare NHS Trust, London, United Kingdom 3 Medicine, Maine Medical Center Research Institute, Scarborough, ME 4 Physiology and Medicine, Dartmouth Medical School, Lebanon, NH Poster 106 OSTEOARTHRITIS IN MICE LACKING 5′-DEIODINASE ACTIVITY

Thyroid Hormone Metabolism & Regulation Thursday Poster Basic

Thyroid hormones control chondrocyte differentiation. The type 1 and 2 deiodinases (D1 and D2) convert T4 to T3 by 5′-deiodination, whereas the type 3 deiodinase (D3) irreversibly inactivates T4 and T3. The activities of D2 and D3 in target tissues determine local intracellular T3 availability. Osteoarthritis is characterized by accelerated articular chondrocyte differentiation and cartilage destruction. Recently, genome-wide association studies have identified D2 and D3 as susceptibility loci for osteoarthritis. Thus, we investigated osteoarthritis susceptibility in mice lacking 5′-deiodinase activity.

Knee joints from 16-week-old adult male D2KO, D1D2KO, and wild-type (WT) mice were analyzed. Five-micrometer coronal and sagittal sections at 80-μm intervals were stained with Safranin-O Fast-Green and scored using the Osteoarthritis Research Society International grading scale of 0 to 6 (0=normal articular cartilage and 6=clefts or erosions extending to the mineralizing front and covering>75% of the articular cartilage). Maximum and standardized osteoarthritis scores were determined.

A maximum osteoarthritis score of 2 was recorded in D2KO, D1D2KO, and WT mice (Kruskal–Wallis, ns, n=3–5). A score of 2 indicates loss of articular cartilage surface lamina and the presence of superficial clefts. Median standardized osteoarthritis scores did not differ among genotypes [WT 7.84 (0–13.5); D2KO 2.07 (0–12.8); D1D2KO 8.26 (0–15.2); median (range) total osteoarthritis score/articular surface, Kruskal–Wallis, ns, n=3–5].

Deletion of D2 or both D1 and D2 did not affect susceptibility to the development of spontaneous osteoarthritis in adult mice. Further investigation of the role of local T3 availability in osteoarthritis will require the use of provocation models in which osteoarthritis is induced, for example, by surgical destabilization of the knee.

1 Institute for Healthcare Studies, Northwestern University, Chicago, IL 2 Department of Surgery, Northwestern University, Chicago, IL 3 Department of Pathology, Northwestern University, Chicago, IL Poster 113 ON-SITE ADEQUACY EVALUATION IS NOT COST EFFECTIVE FOR EXPERIENCED OPERATORS PERFORMING INITIAL ULTRASOUND-GUIDED FINE-NEEDLE ASPIRATION OF THYROID NODULES

Thyroid Nodules & Goiter Thursday Poster Clinical

On-site evaluation (OSE) of cytohistologic adequacy during fine-needle aspiration (FNA) reduces the rate of unsatisfactory results, but adds cost. We hypothesized that the addition of routine OSE to initial ultrasound-guided FNA of thyroid nodules is not cost effective.

Formal cost-effectiveness analysis from the societal perspective was performed using a decision model to compare strategies of routine initial OSE versus restriction of OSE to cases of prior unsatisfactory FNA. All FNAs performed with OSE were assumed to be adequate. Adequacy rates for FNA without OSE and utility adjustment for undergoing repeat FNA were estimated based on the literature review and institutional experience. Costs in 2011 US$ were estimated using Medicare limiting charges and Bureau of Labor Statistics wage rates. A one-time utility adjustment of 0.25 days was assigned to outcomes requiring repeat FNA. The threshold for cost effectiveness was defined as an incremental cost-effectiveness ratio of $100,000/quality-adjusted life year (QALY). Sensitivity analysis was used to examine the uncertainty of probability, utility, and cost estimates.

The routine OSE strategy produced a gain of 0.00007 QALY at an additional cost of $43.75 for an incremental cost-effectiveness ratio of $639,144/QALY when compared to restriction of OSE to cases with prior unsatisfactory results. On sensitivity analysis, routine OSE became cost effective if the FNA adequacy rate without OSE decreased from 90% to 85%; the cost of OSE decreased from $116 to $75; the cost of FNA increased from $366 to $735; hourly wage increased from $23 to $115, or utility detriment for repeat FNA increased from 0.25 to 1.6 days.

OSE for initial ultrasound-guided FNA of thyroid nodules is not cost effective unless the adequacy rate without OSE is <85%. When experienced operators perform FNA, OSE should be reserved for cases with previous unsatisfactory results.

1 Experimental Therapeutics, Ohio State University Medical Center, Columbus, OH 2 Endocrinology, University of Pisa, Pisa, Italy 3 Nuclear Medicine, Universitatsklinikum Essen, Essen, Germany 4 General Medical Oncology, UZ Leuven, Leuven, Belgium 5 Otorhinolaryngology, University of Pennsylvania Health System, Philadelphia, PA 6 Medical Oncology, Instituto Nazionale dei Tumori, Milan, Italy 7 Centrum Onkologii, Instytut im. M. Sklodowskiej-Curie Oddzial w Gliwicach, Gliwicach, Poland 8 Brachytherapy, Medical Radiology Research Center of RAMS, Obninsk, Russian Federation 9 Nuclear Medicine, Universitatsklinikum Wurzburg, Wurzburg, Germany 10 Surgery, Medizinische Universitat Wien, Vienna, Austria 11 Hematology Oncology, University of Chicago Medical Center, Chicago, IL 12 Hematology Oncology, Massachusetts General Hospital, Boston, MA 13 Hematology Oncology, Henry Ford Health System, Detroit, MI 14 Clinical Development, Exelixis, South San Francisco, CA 15 Endocrinology, Johns Hopkins University School of Medicine, Baltimore, MD 16 Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 17 Endocrine Neoplasia and Hormonal Disorders, U Texas MD Anderson Cancer Center, Houston, TX 18 Nuclear Medicine, Institut Gustave Roussy, Villejuif, France Oral 17 CLINICAL ACTIVITY OF CABOZANTINIB (XL184) IN MEDULLARY THYROID CARCINOMA (MTC) PATIENTS (PTS): SUBGROUP ANALYSIS IN THE PHASE 3 STUDY (EXAM)

Thyroid Cancer Friday Oral Clinical 5:00 PM

The majority of MTC cases occur sporadically, while the rest arise as part of inherited autosomal dominant syndromes. Germline mutations in RET are present in patients with inherited MTC, and tumor-associated RET mutations are found in up to 65% of patients (pts) with sporadic MTC. The common mutation RET M918T indicates poor prognosis. Bone metastases (mets) are common and debilitating events.

Pts were required to have documented RECIST progression within 14 months of screening. There were no restrictions on prior therapies, including treatment with tyrosine kinase inhibitors (TKIs). The primary endpoint was progression-free survival (PFS) as assessed by an independent radiology committee using RECIST. Objective response rate (ORR) was a secondary endpoint. Prespecified subgroup analyses included prior use of TKI, RET mutation status, and presence of bone mets.

Overall, 330 pts (RET mutation status: pos 48.2%, neg 12.4%, unk 39.4%; prior TKI: yes 20.6%, no 77.9%, unk 1.5%; bone mets: yes 49.4%, no 49.4%) were randomized 2:1 to cabozantinib (cabo, 140 mg free-base qd, n=219) or placebo (P, n=111). At the primary endpoint analysis, PFS was significantly prolonged (est median 11.2 mo for cabo vs. 4.0 mo for P, HR 0.28, 95% CI 0.19–0.40, p<0.0001). Overall, PFS results favored the cabo group across all subgroup analyses. RET mutation pos, neg, and unk subgroups showed HRs of 0.24, 0.47, and 0.30, respectively. Pts with hereditary and sporadic MTC showed HRs of 0.08 and 0.32. The poor prognosis subgroup of RET M918T-positive pts showed PFS HR of 0.17. The HRs for pts with and without bone mets at baseline were similar. Prior use of TKIs did not adversely impact response to cabo (HR=0.16). ORR was 28% for cabo vs. 0% for P (p<0.0001). ORR was consistent across subgroups, varying between 25% and 32% for the RET mutation status subgroups, and 21% each for pts with bone mets or prior TKI treatment. Analysis of tumor RAS mutation status is ongoing, and subgroup analysis will be presented.

The study met its primary objective of demonstrating substantial PFS prolongation with cabo vs. P in pts with progressing MTC. PFS results favored the cabo arm across prespecified subgroups.

1 ARUP Institute, ARUP Laboratories, Salt Lake City, UT 2 Department of Pathology, University of Utah, Salt Lake City, UT 3 Department of Medicine, University of Utah, Salt Lake City, UT 4 Department of Laboratory Medicine, University of Washington, Seattle, WA Oral 18 MASS SPECTROMETRY-BASED METHOD FOR ACCURATE MEASUREMENT OF THYROGLOBULIN THAT OVERCOMES INTERFERENCE OF ANTITHYROGLOBULIN AUTOANTIBODIES

Thyroid Cancer Friday Oral Clinical 5:15 PM

Quantitative measurement of thyroglobulin (Tg) plays an important role in the follow-up of patients treated for differentiated thyroid cancer (TC). Circulating Tg autoantibodies (Tg-AAb) can mask epitopes and cause false-negative results when tested with immunoassay (IA). As a result, commercially available Tg IAs are unreliable for accurate measurement of Tg in many patients. We developed a liquid chromatography–tandem-mass spectrometry (LC-MS/MS) method that overcomes the drawbacks of commercial IAs and allows accurate measurement of Tg in the presence of Tg-AAb.

Tg is enriched from human serum samples; proteins are denatured, reduced, and digested using trypsin. A Tg-specific tryptic peptide is then enriched from the digests using antipeptide antibody conjugated to magnetic beads. After the enrichment, the samples are analyzed using LC-MS/MS; the analysis cycle time is 6.5 min per sample.

Limit of quantitation of Tg in serum was 0.5 ng/mL (0.75 fmol/mL). The mean imprecision of triplicate measurements in serum samples over 5 days (concentrations range 2 to 400 ng/mL) was 5.2%. Comparison with Beckman Coulter Access IA using serum samples free of Tg-AAb (n=61) showed good agreement between the methods; LC-MS/MS=1.05*IA+1.9, r=0.916, Sy/x=12.8. A set of 69 samples tested positive for Tg-AAb (Tg-AAb concentrations 19 to 3000 IU/mL; Tg recovery 27 to 97%) was analyzed by this LC-MS/MS method, and the concentrations were compared to the concentrations determined with a Beckman Coulter analyzer. In 16% of samples, concentrations of Tg measured by the IA were false negative, while concentrations determined by the LC-MS/MS method were above 1 ng/mL. False-negative results were likely caused by presence in the samples of Tg-AAb that interfered with the IA.

Proteolytic digestion of serum samples releases a Tg peptide targeted in the method and removes endogenous Tg-AAb that can interfere with traditional IA. This method has sensitivity and robustness sufficient for a routine clinical use. The method allows quantification of femtomolar quantities of Tg in the presence of Tg-AAb and would allow detecting recurrence of TC in patients with Tg-AAb more accurately than the immunoassays.

1 Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom 2 Department of Clinical Biochemistry, Addenbrookes Hospital, Cambridge, United Kingdom 3 Paediatric Department, Maternity & Children's Hospital & Taibah University, Al-Madinah, Saudi Arabia Oral 19 HOMOZYGOUS RESISTANCE TO THYROID HORMONE: CAN CARDIAC COMPLICATIONS BE PREVENTED?

Thyroid Hormone Action Friday Oral Clinical 5:30 PM

Resistance to thyroid hormone (RTH) is usually due to heterozygous mutations in the THRB gene with rare cases being homozygous for receptor defects. Here, we describe an RTH case due to a homozygous TRβ mutation (R243Q).

We describe the clinical and biochemical features of a consanguineous family with RTH.

The Proband (man, 8.4 yrs), was born at term with low birth weight (1.9 kg) to consanguineous parents. A prominent nasal bridge, goiter, and low body weight (10th centile) were noted; he has recurrent tonsillitis and is hyperactive, but has normal auditory function. Echocardiography showed mitral and tricuspid regurgitation, and 24-hour cardiac monitoring recorded sinus tachycardia. His circulating thyroid hormones (FT4>4-fold; FT3>8-fold raised) are very elevated, with normal TSH levels (see Table). THRB gene sequencing showed homozygosity for a nucleotide substitution, corresponding to an arginine-to-glutamine change at codon 243 (R243Q) in TRβ. Less abnormal thyroid function (FT4 1.2–1.8-fold, FT3 1.2–1.9-fold raised) in each parent and 3 siblings (see Table) was associated with heterozygosity for the R243Q TRβ mutation. Goiter, hyperactivity, and recurrent infections had also been noted in another sibling. He developed mitral regurgitation and cardiomegaly and died of heart failure at 13 years, despite diuretic therapy. Although his THRB mutation status is unknown, elevation of his thyroid hormones (FT4>3-fold, FT3>13-fold raised, see Table) comparable to the Proband suggests homozygous RTH, with cardiac hyperthyroidism contributing to his mortality

Previous studies indicated unique properties of R243Q TRβ, with normal T3 binding to mutant receptor in solution, but significantly impaired ligand-dependent dissociation of mutant receptor homodimers bound to DNA and delayed corepressor release. These characteristics likely account for unexpectedly significant dominant negative inhibition by R243Q mutant TRβ in vitro, correlating with our observed severe homozygous RTH phenotype. Future management, including prevention of possible cardiac decompensation in the proband, will be a therapeutic challenge.

1 Endocrinology and Metabolism, Academic Medical Center Amsterdam, Amsterdam, Netherlands 2 Obesity and Metabolic Health, Rowett Institute of Nutrition and Health, Aberdeen, United Kingdom Oral 23 LPS INDUCES NFKB P65 AND TYPE 2 DEIODINASE IN A PRIMARY TANYCYTE CULTURE

Thyroid Hormone Metabolism & Regulation Friday Oral Basic 5:00 PM

Nonthyroidal illness syndrome (NTIS) is associated with decreased TRH expression in the paraventricular nucleus (PVN) of the hypothalamus. This is probably due to increased local production of T3 by type 2 deiodinase (D2), an enzyme that is expressed in tanycytes lining the wall of the third ventricle. Administration of lipopolysaccharide (LPS), which is an established model of NTIS in rodents, increases D2 expression in tanycytes. We studied the involvement of the inflammatory signal transduction pathways in LPS-induced upregulation of D2 in tanycytes using an in vivo and in vitro approach.

For the in vivo approach, mice were injected intraperitoneally with bacterial endotoxin (LPS) or saline, and the periventricular area (PE) and arcuate nucleus region (ARC) were isolated. An in vitro model was established using a primary culture of tanycytes from the brains of 10-day-old rat pups. These cultures were stimulated with LPS for 6 hours. We assessed mRNA expression of NFkB p65, JNK, and C/EBPa mRNA as key elements of the inflammatory pathway by qPCR. The presence of tanycytes in primary cell cultures was confirmed by qPCR for DARPP-32, nestin, vimentin, and GFAP and immunostaining for vimentin and GFAP.

NFkB p65 and C/EBPa mRNA levels were increased in the PE and ARC of mice 4 and 8 hours after LPS administration. The tanycyte cultures expressed DARPP-32, nestin, vimentin, and GFAP mRNA and showed immunostaining for vimentin and GFAP, indicating the presence of tanycytes and additional glial cell types in the culture. LPS stimulation of the tanycyte cultures resulted in an increase in D2 and NFkB p65 mRNA expression. No changes were found in mRNA levels of C/EBPa and JNK.

Our results suggest a role for NFkB p65 in the upregulation of D2 in tanycytes during inflammation. Future experiments will include gene-silencing methods to further elucidate the mechanism of inflammation-induced D2 increase in the hypothalamus.

1 Otorhinolaryngology: Head and Neck Surgery; Medicine, Hematology/Oncology, Abramson Cancer Center, Philadelphia, PA 2 Endocrinology, University of Pisa, Pisa, Italy 3 Nuclear Medicine, Institut Gustave Roussy, Villejuif, France 4 Nuclear Medicine, Universitatsklinikum Essen, Essen, Germany 5 General Medical Oncology, UZ Leuven, Leuven, Belgium 6 Experimental Therapeutics, Ohio State University Medical Center, Columbus, OH 7 Medical Affairs, Exelixis, South San Francisco, CA 8 Nonclinical Development, Exelixis, South San Francisco, CA 9 Endocrinology, Johns Hopkins University School of Medicine, Baltimore, MD 10 Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 11 Endocrine Neoplasia and Hormonal Disorders, U Texas MD Anderson Cancer Center, Houston, TX Oral 25 CORRELATIVE BIOMARKER ANALYSIS IN THE EXAM TRIAL, A PHASE 3 STUDY OF CABOZANTINIB (XL184) IN PATIENTS (PTS) WITH MEDULLARY THYROID CARCINOMA (MTC)

Thyroid Cancer Friday Oral Basic 5:30 PM

We conducted a Phase 3 study of cabozantinib (cabo, an oral inhibitor of MET, VEGFR2, and RET) versus placebo (P) in patients with progressive MTC. At the primary endpoint analysis, PFS was significantly prolonged (est median 11.2 mo for cabo vs. 4.0 mo for P, p<0.0001). Exploratory correlative analyses of RET mutational status with PFS and tumor markers calcitonin (CT) and carcinoembryonic antigen (CEA) with tumor response were performed. The effects of cabo treatment on the mechanism-based plasma biomarker sVEGFR2 were explored.

Plasma and serum samples were evaluated for levels of sVEGFR2, CT, and CEA. RET mutational status was determined from blood and archival tumor samples using Sanger and large-scale parallel sequencing methods.

sVEGFR2 showed a cabo-dependent decrease on Day 29 of 33% (p<0.0001) compared to no change with placebo. There was a modest correlation between the extent of biomarker reduction and cabo plasma exposure on Day 29. At week 12, levels of CT and CEA had risen in the P group compared to baseline (57% and 89%, respectively, p<0.0001), but had fallen in the cabo group (-45% and −23%, respectively, p<0.0001). There were statistically significant correlations between the percent change in CT or CEA and the percent change in the sum of target lesion diameters at week 12. Pts achieving biochemical partial response (>50% decrease in CT or CEA) were more likely to have objective tumor response than subjects with biochemical progressive disease (>50% increase). Of the 330 patients enrolled in the study, RET mutation status was determined for 200 (61%). Of these, 79.5% and 20.5% were RET mutation positive and negative, respectively; the mutation most frequently found was M918T (74% of RET-positive pts). PFS hazard ratios and tumor response rates favored the cabo arm among all RET mutation subgroups. RAS mutations are common in RET-negative tumors, and analysis of tumor RAS mutation status is ongoing.

Correlative biomarker studies support the proposed mechanism of action for cabo in the setting of MTC, with decreases in VEGFR2 pathway-related and tumor-related biomarkers, and clinical activity found in both RET mutation-positive and negative pts.

1 Endocrine Research Centre, Research Institute for Endocrine Sciences, Shahid Beheshti University (MC), Tehran, Islamic Republic of Iran 2 Canada's Michael Smith Genome Sciences Centre, British Columbia Cancer Research Centre, Vancouver, BC, Canada Oral 26 DNA POOL-BASED GENOME-WIDE ASSOCIATION SCAN IDENTIFIES NOVEL LOCI ASSOCIATED WITH AUTOIMMUNE THYROID DISEASE IN THE TEHRAN LIPID AND GLUCOSE STUDY

Autoimmunity Friday Oral Basic 5:45 PM

Epidemiologic studies strongly implicate a genetic contribution to autoimmune thyroid disease (AITD). We used a multistage strategy to identify genetic variants associated with AITD using a DNA pooling-based genome-wide association study (GWAS) of 1,000,000 single-nucleotide polymorphisms (SNPs) in the Iranian population.

A population-based sample from the Tehran Lipid and Glucose Study (TLGS) was used. In the first stage, 1434 subjects aged >20 years from the TLGS were assessed for autoantibody to thyroid peroxidase (TPOAb) levels. AITD was defined as TPOAb levels ≥100 IU/mL; subjects with low (<20 IU/mL) TPOAb levels were chosen as controls. Subjects were age- and sex-matched and assigned to the AITD (n=100, mean age 42.1±13.3 yrs) or control group (n=162, mean age 42.0±13.1 years). Each DNA pool was allelotyped on 4 Illumina Human1M-Duo arrays, and allelotype-based tests of association were used to rank SNPs using GenePool software. In the second stage, to validate and replicate high-ranking SNPs by individual genotyping, we selected 116 SNPs. SNPs were chosen based on two criteria: GenePool-based rank and supporting high rankings of other SNPs in high-linkage disequilibrium with the SNP of interest. The 116 SNPs were genotyped in individual DNA samples from 811 Iranian samples (189 AITD individuals, 74 participated in pools; 622 control individuals, 123 participated in pools) using Sequenom MassArray iPLEX assays.

About 115 SNPs were genotyped successfully and tested for association with AITD using logistic regression implemented in PLINK 1.07. Twenty-six SNPs were associated with AITD (uncorrected p-values 0.05–5.4×10⁻⁵), of which 2 SNPs at novel loci (9q33.2 and 20q11.2) remained significant after Bonferroni correction for 115 tests (P_adjusted=6.2×10⁻³, OR=1.96 and P_adjusted=3.5×10⁻²; OR=1.63; respectively). Replication of the most significant markers in ∼1,500 additional AITD (∼500) and controls (∼1,000) is underway.

We have identified novel loci associated with AITD using a multistage DNA pool-based GWAS. Discovery of AITD susceptibility genes holds promise to provide insights into the mechanisms of this disease.

1 Kolling Institute, University of Sydney, Sydney, NSW, Australia 2 Medicine, University of Sydney, Sydney, NSW, Australia 3 Endocrinology, Royal North Shore Hospital, Sydney, NSW, Australia Oral 27 FOXE1 FUNCTIONALLY INTERACTS WITH ELK1 ON THYROID-SPECIFIC GENE PROMOTERS

Thyroid Cancer Friday Oral Basic 6:00 PM

Genetics variants such as rs1867277 close to FOXE1 are strongly associated with papillary thyroid cancer (PTC). We have recently shown that rs1867277 is in tight linkage disequilibrium with a polymorphic polyalanine tract located within FOXE1. We also found that FOXE1 transcriptional activity is altered according to the polyalanine tract length. The aim of this study was to identify FOXE1 cofactors, to assess whether transcriptional disruption by a longer polyalanine tract was due to altered cofactor affinity.

Potential cofactors from Nthy-ori-3.1 cells were identified using a FLAG-FOXE1 construct and the TranSignal™ TF-TF Array Kit (Panomics, Inc., Redwood City, CA). Endogenous FOXE1 and ELK1 were coimmunoprecipitated from Nthy cell extracts. Mammalian two-hybrid assays were performed by transient transfection of GAL4-FOXE1 (C-terminus) and VP16-ELK1 into Nthy cells together with pG5Luc. Nthy cells were also transfected with expression vectors for full-length FOXE1 and ELK1 together with TPO-Luc. For some experiments, EGF (25 ng/mL) or PD98059 (10 uM) was added. ChIP assays were performed using DNA isolated from Graves' thyroid tissue.

The strongest signal identified in the TF-TF array corresponded to ELK1, a transcriptional effector of MAPK activation. FOXE1-ELK1 interaction was confirmed by (a) coimmunoprecipitation of endogenous FOXE1 and ELK1 from Nthy cells; (b) mammalian two-hybrid assays; and (c) cotransfection of full-length FOXE1 and ELK1 on TPO-Luc. Chromatin immunoprecipitation assays confirmed that both proteins simultaneously occupy binding sites within the TPO and TG proximal promoters in human thyroid tissue. MAPK stimulation by EGF treatment disrupted FOXE1-ELK1 interaction as assessed by co-ip. Conversely, treatment of SW1736 thyroid cells (containing BRAFV600E) with a MEK inhibitor (PD98059) increased TPO-Luc expression.

We identified ELK1 as a novel interacting partner of FOXE1. This interaction is sensitive to MAPK activation. Since PTC is essentially dependent on somatic alteration of the MAPK pathway genes, our observations may explain at least in part the association between FOXE1 germline variants and PTC.

1 Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 2 Division of Endocrinology, Department of Medicine, Mayo Clinic, Rochester, MN Oral 28 THYROID CANCER-DERIVED THYROGLOBULIN LACKS IODINATION AND CAN BE DISTINGUISHED FROM NORMAL THYROGLOBULIN BY MASS SPECTROMETRY

Thyroid Cancer Friday Oral Basic 6:15 PM

Iodination of thyroglobulin (Tg) differs between benign and malignant thyroid tissue. If the precise nature of these differences could be determined and shown to be consistent, assessment of Tg iodination status might become a tool to augment cytological diagnosis of thyroid nodules. We explored this possibility using comparative mass spectrometric assessment of Tg iodination status in metastatic papillary carcinoma (PTC) and benign thyroid nodules.

Four different preparations of purified normal human Tg were digested with trypsin, chymotrypsin, and GlucC to maximize peptide coverage and analyzed by high-resolution LC-MS/MS (ABSciex 5600 Q-TOF). Proteotypic peptides containing consistently iodinated sites were identified by protein database search, focusing on iodination. A total of 20 monoiodinated tyrosines, 11 di-iodo tyrosines, 1 thyroxine, and 1 monoiodinated histidine were found. Based on consistent high iodination, peptides spanning 6 of these sites (4 monoiodinated and 2 mono- and di-iodinated) were selected for quantification by selective reaction monitoring MS/MS in benign and malignant thyroid tissues. The two most intense of these peptide pairs (SHGQDSPAVY*LK and ENILLEPY*) were then quantified in 8 benign thyroid nodule fine-needle aspiration biopsy (FNAB) needle washes and 13 FNAB needle washes from neck lymph nodes with metastatic PTC.

Of the 13 malignant specimens, 2 had insufficient signal for evaluation. The remaining 11 specimens contained almost exclusively the noniodinated versions of the tested peptides, with ratios of noniodinated peptides to matched iodinate peptides of >15:1. One of the 8 benign thyroid FNABs also had insufficient signal for evaluation. Among the 7 benign specimens with adequate signals, all showed identifiable iodinated peptide signals in addition to the noniodinated signals, with ratios of noniodinated to matched iodinated peptides of ∼2:1.

Tg from metastatic PTC lacks iodination, while iodination is strong and consistent in benign thyroid nodules. Measurement of Tg iodination status by mass spectrometry may allow differentiation between benign and malignant thyroid lesions.

1 Section of Endocrinology, Dept. of Clinical and Experimental Medicine & Pharmacology, University of Messina, Messina, Italy 2 Intern Departmental Program of Molecular & Clinical Endocrinology and Women Endocrine Health, University Hospital, Messina, Italy 3 Faculty of Pharmacy, University of Montreal, Montreal, QC, Canada 4 Pharmametrics, Learn and Confirm Inc., St-Laurent, QC, Canada Poster 118 EFFECT OF PROTON-PUMP INHIBITORS (PPIS) ON THE RELATIVE BIOAVAILABILITY OF LEVOTHYROXINE (LT4) IN SOFT-GEL CAPSULES AND IN TABLETS

Disorders of Thyroid Function Friday Poster Clinical

A novel formulation of LT4, in which the hormone is dissolved in a glycerin environment and protected by a soft gelatin shell (Tirosint capsule, IBSA, Switzerland), is bioequivalent to reference LT4 tablet (Synthroid, Abbott, USA) [Colucci et al. Ther Drug Monit 2011;33]. Recently, the capsule showed superiority over the tablet in the setting of coffee-induced LT4 malabsorption [Benvenga et al. Thyroid 2011;21(1)]. PPIs are known to impair the intestinal absorption of LT4.

To evaluate the effect of PPIs on the absorption of LT4 in capsules and in tablets, an acute oral loading test with 600 μg LT4 of either formulation ingested with 240 mL water after an overnight fast was conducted in 16 healthy volunteers (8 per treatment). With a random crossover design, the volunteers repeated the test after being challenged with an acute infusion of 80 mg esomeprazole. Blood sampling was performed from predose up to 24 h postdose. Intragastric pH was monitored by a nasogastric tube.

In baseline (non-PPI) condition, AUC0-24, 0–6 or 0–1 h were (capsule vs. tablet) 788.9±158.1 vs. 867.2±162.3 (−9.0%), 226.7±58.4 vs. 248.9±58.8 (−8.9%), or 5.4±7.6 vs. 9.8±6.1 ngxh/mL (−45.0%) (p>0.20). Cmax was, respectively, 56.8±20.7 vs. 55.4±11.6 ng/mL. Under PPI infusion, absorption of LT4 decreased to a lower extent, compared to the corresponding baseline condition, when LT4 was in capsule. Indeed, capsule AUC0-24, 0–6 or 0–1 h were 743.7±142.1 (−5.7% compared to the aforementioned baseline values), 206.0±54.9 (−9.2%), or 5.6±8.1 (+3.3%). In contrast, tablet AUC0-24, 0–6 or 0–1 h were 776.6±135.9 (−10.4% vs. baseline), 202.3±35.4 (−18.8%), or 7.2±3.8 (−26.6%). Under PPl infusion, Cmax decreased by only 2.8% with the capsule, but by 13.0% with the tablet, compared to the corresponding baseline values.

Under the stressful test of alkalinizing the intragastric pH with PPIs, the absorption of L-T4 from the capsule appears to be far less affected than from the tablet. This in vivo more favorable profile of the capsule is consistent with the in vitro data [Pabla et al. Eur J Pharm Biopharm 2009;72] showing a more favorable dissolution profile of the capsule compared to either reference or generic tablets over a wide range of pH changes.

1 Section of Endocrinology, Department of Clinical & Experimental Medicine and Pharmacology, University of Messina, Messina, Italy 2 Interdepartmental Program of Molecular and Clinical Endocrinology & Women's Endocrine Health, University Hospital, Messina, Italy Poster 119 INTERFERENCE OF L-T4 ABSORPTION BY PROTON-PUMP INHIBITORS (PPIS) CAN BE SOLVED BY A LIQUID FORMULATION OF L-THYROXINE (L-T4)

Thyroid Nodules & Goiter Friday Poster Clinical

By increasing the gastric pH, PPIs impair the dissolution of conventional L-T4 sodium salt tablets before intestinal absorption. We wondered if a liquid formulation of L-T4, already available in our country (Tirosint oral solution, IBSA, Italy), could solve the problem of L-T4 tablet malabsorption that is caused by concurrent therapy with PPIs. This new formulation contains L-T4 (which is a lipophilic hormone) already solubilized in an organic solvent (100 μg L-T4 sodium salt in 243 mg ethanol), and thus ready to be absorbed.

Upon consent, we enrolled 15 such patients (12 F, 3 M), 7 of whom used to take omeprazole, 5 pantoprazole, and 3 lansoprazole. Six out of 15 (40%) were under replacement therapy (REP), while 9/15 (60%) under suppressive therapy (SUP). They were switched to the liquid formulation, maintaining the same daily dose of L-T4. Serum TSH was rechecked at least 2 months after switch. Statistics included Mann–Whitney and Fisher's exact tests.

In the REP or SUP group, serum TSH averaged 2.77±2.05 or 1.15±1.85 mIU/L while taking the L-T4 tablet, but 1.63±0.66 (p=0.087 vs. 2.77±2.05) or 0.12±0.12 (p<0.0001 vs. 1.15±1.85), while under liquid L-T4 for at least 2 months. In the SUP group, the rates of TSH levels ≤0.10 mU/L were 0/19 assays under the tablet vs. 17/22 (77%) assays under the liquid formulation (p<0.001). During the follow-up, the daily dose of liquid L-T4 had to be decreased in 2/9 (10%) SUP patients.

Our data demonstrate that the liquid formulation of L-T4 is capable to solve the problem of incomplete absorption caused by PPIs, because it can be directly absorbed, irrespective of the gastric pH.

1 Section of Endocrinology, Department of Clinical & Experimental Medicine and Pharmacology, University of Messina, Messina, Italy 2 Section of Dermatology, Department of Social Medicine of the Territory, University of Messina, Messina, Italy 3 Department of Developmental Biology, Stanford University, School of Medicine, Stanford, CA 4 Internal Medicine, Stanford University, School of Medicine, Palo Alto, CA 5 Interdepartmental Program of Molecular and Clinical Endocrinology & Women's Endocrine Health, University Hospital, Messina, Italy Poster 120 A CASE OF GRAVES' DISEASE (GD) TRIGGERED BY IMMUNOTHERAPY WITH THE TUMOR-ASSOCIATED ANTIGEN NY-ESO-1

Autoimmunity Friday Poster Clinical

Vaccine immunotherapy for malignancies is based on the administration of tumor-associated antigens (TAAs) that are bound by specific HLA molecules. Immunotherapy with NY-ESO-1, a TAA expressed by a number of malignancies, triggered hyperthyroidism or hypothyroidism in two HLA-A2 patients with ovarian cancer (Clin Cancer Res, 2008). Here, we report a case of GD triggered by vaccination with NY-ESO-1 in one HLA A2-negative woman with a different malignancy.

A 32-year-old woman with a synovial sarcoma was treated with radiotherapy, chemotherapy, and NY-ESO-1 combined with an immune adjuvant. Immunotherapy was given for two cycles, each cycle consisting of 5 administrations. The patient typed HLA A11/A33(19), B13/B56(22), Cw3/. One month after having started immunotherapy, clinical thyroid dysfunction was suspected. Data were consistent with hyperthyroidism due to GD, with low TSH (0.02 mU/L), high FT3 (7.4 pmol/L), FT4 (26.2 pmol/L), and thyroid-stimulating immunoglobulins (TSI) (152%, normal range<140). Hyperthyroidism worsened progressively (FT4>60, FT3>30, TSI>500), so that the patient was eventually thyroidectomized. Thyroid histology confirmed GD. Therefore, using the NCBI software BLAST (http://blast.ncbi.nlm.nih.gov/Blast.cgi), we looked for amino acid sequence homologies between NY-ESO-1 and thyroid autoantigens [TSH-receptor (TSH-R), thyroperoxidase (TPO) and thyroglobulin (Tg)]. Using the HLA ligand/motif database (Tissue Antigens, 2003), we searched the HLA-binding motifs in the regions of NY-ESO-1 and thyroid autoantigens that were homologous.

We found 15 regions of NY-ESO-1, all epitopic, which were homologous to 15 regions of thyroid autoantigens, some of which epitopic: 5 segments of TSH-R, 8 of Tg, and 2 of TPO. These homologous segments contain binding motifs belonging to several HLA class I antigens, including the patient's A11 and A33. Furthermore, 2 homologous segments of TSH-R contain HLA-A2-binding motifs.

As vaccines are emerging as a standard treatment for malignancies, vaccine-induced thyroid dysfunctions are expected to increase in genetically predisposed patients over the next years.

1 State Key Laboratory of Medical Genomics, Ruijin Hospital, Shanghai, China 2 Department of Endocrinology, Shanghai Institute of Endocrinology and Metabolism, Shanghai, China Poster 121 ROBUST ASSOCIATIONS OF SIX NEW LOCI FROM GENOME-WIDE ANALYSES OF GRAVES' DISEASE

Autoimmunity Friday Poster Basic

Graves' disease (GD), a common autoimmune disorder characterized by autoantibodies targeting antigens specifically expressed in thyroid tissues, is triggered by a combination of genetic and environmental factors.

To enrich the genetic architecture of GD, we carried out a three-stage genome-wide association study in ∼20,000 subjects to identify new susceptibility loci for GD.

We found strong evidence in the overall populations for six previously undetected or indefinite susceptibility loci: the C1QTNF6-RAC2 region at 22q12-13, SLAMF6 at 1q23.2, ABO at 9q34.2, TG at 8q24.22, GPR174-ITM2A at Xq21.1, and an intergenic region at 14q32.2 (P_combined<5×10–8). We also found significant heterogeneity between the sexes in the associations of rs5912838 at Xq21.1 and rs2284038 at 22q13.1.

This study increases the number of GD loci with compelling evidence from 9 to at least 15.

1 Molecular Thyroid Research Laboratory, Gutenberg University Medical Center, Mainz, Germany 2 Dept. of Pediatrics, Endocrinology, Diabetology with the Cardiology Division, Medical University in Bialystok, Bialystok, Poland 3 Dept. of Pediatrics in Zabrze, Medical University of Silesia, Katowice, Poland 4 Dept. of Cardiology, Internal Affair and Administration, Ministry Hospital, Bialystok, Poland 5 Dept. of Pediatrics, Preyersches Kinderspital, Vienna, Austria 6 Dept. of Pediatrics, Section Endocrinology and Diabetology, University Hospital, Ulm, Germany 7 R & D, Diagnostic Hybrids, Inc., Athens, OH Poster 122 THYROID-STIMULATING AUTOANTIBODIES ARE A BIOMARKER FOR THYROID-ASSOCIATED ORBITOPATHY IN CHILDREN WITH AUTOIMMUNE THYROID DISEASES—A PROSPECTIVE MULTICENTER TRIAL

Autoimmunity Friday Poster Clinical

Thyroid-stimulating autoantibodies (TSAbs) mediate the activity of Graves' disease (GD) and thyroid-associated orbitopathy (TAO). Scarce data are available on the relevance of TSAbs in children with autoimmune thyroid diseases (AITD). Thus, we aimed to detect and follow serum levels of TSAb in a large pediatric cohort with AITD.

TSAbs were measured with the help of a FDA-cleared chimeric TSH receptor bioassay. TSAbs were reported as percentage of specimen-to-reference ratio (SRR%, cutoff 140%). Thyroid-binding inhibiting immunoglobulins (TBIIs) were also measured in all samples.

A total of 212 serum samples were collected from 172 pediatric patients with AITD: 32 with GD (30 female children, mean age±SEM 13.4±0.7 years, 11 with TAO), 68 with Hashimoto's thyroiditis (HT, 57 female children, 13.4±0.4 yrs.), 27 with type 1 diabetes (T1D, 14 female children, 14±0.5 yrs.), 5 with juvenile arthritis (JA, two female children, 14.3±1.5 yrs.), and 40 healthy controls (C, 18 female children, 12.5±0.7 yrs.) were evaluated for the presence of TSAbs and TBIIs. Of 53 measured samples with GD, TSAbs were detected in 47 (89%) in contrast to TBII positivity in 40 (75%), only (p<0.0001). All six TSAb-negative samples were from euthyroid, pretreated patients. Mean serum TSAb levels were SRR% 403±24 and 239±63 (p=0.02) in untreated and treated children with GD, respectively. Mean TSAb levels were markedly higher (p=0.03) in children with (SRR% 434±27) vs. without (317±37) TAO. Also, in two children with HT and TAO, TSAbs were present (SRR% 429 and 215). In contrast, in the pediatric HT patients without TAO, mean TSAb levels were SRR% 51±4. All 13 children with TAO were TSAb positive, but only 11 (85%) were TBII positive. All children with T1D, JA, and/or C samples were TSAb negative.

These novel data demonstrate the close association between TSAbs and TAO in a large pediatric collective with AITD.

1 Molecular Thyroid Research Laboratory, Gutenberg University Medical Center, Mainz, Germany 2 R & D, Diagnostic Hybrids Inc., Athens, OH Poster 123 ANALYTICAL PERFORMANCE OF TWO-CHIMERIC TSH RECEPTOR BIOASSAYS FOR THYROID-STIMULATING AND BLOCKING AUTOANTIBODIES

Autoimmunity Friday Poster Translational

The analytical performance of two-chimeric TSH receptor (TSHR) bioassays for measuring TSHR-stimulating (TSAb) and blocking (TBAb) autoantibodies was investigated.

Chinese hamster ovary cells expressing a chimeric TSHR were grown for 15–18 hours at 37°C. Limits of Blank (LoB), Detection (LoD), and Quantitation (LoQ) were measured according to the standardized CLSI EP17-A protocol with the help of commercially available monoclonal thyroid-stimulating (M22) and blocking (K1-70) autoantibodies (MAb). In the TSAb bioassay, cells were treated with M22 dilutions and for TBAb with bovine TSH, K1-70 dilutions, and/or patient serum. Results for TSAb or TBAb were expressed as percentage of specimen-to-reference ratio (SRR%) or as percent inhibition of luciferase expression relative to induction with bTSH alone.

In the TSAb bioassay, LoB and LoD were measured 40 times in duplicate with 1:11 diluted control serum and with eight low M22 concentrations ranging 0.09–0.005 ng/mL, respectively. Each M22 concentration was measured 20 times in duplicate. For TBAb, LoB was measured using 1200+ replicates of 350 control sera. LoD was measured with 100+ replicates with the K1-70 concentrations 10–0.3125 ng/mL in twofold serial dilutions. The half-maximal effective concentration (EC50) was determined based on the dose–response curve obtained with the M22 concentrations 100–0.003 ng/mL in twofold serial dilutions and with the K1-70 concentrations 100–0.1 ng/mL in fourfold serial dilutions, respectively. In the TSAb bioassay, LoB, LoD, and EC50 were found to be 76.09 SRR%, 90.47 SRR%, and 0.02 ng/mL M22, respectively. LoD and LoQ were both determined to be 0.02 ng/mL of M22. With the TBAb bioassay, LoB, LoD, and EC50 were found to be 30.2%, 43.4% inhibition, and 2.44 ng/mL K1-70, respectively. LoD was 1.25 ng/mL of K1-70. Thus, both bioassays detect very low concentrations of MAb.

The data demonstrate the analytical performance of these novel bioassays.

1 Endocrinology, Deenanath Mangeshkar Hospital & Research Centre, Pune, India 2 Endocrinology, BYL Nair Hospital & Research Centre, Mumbai, India Poster 124 CLINICAL AND BIOCHEMICAL PROFILE OF SUBCLINICAL HYPOTHYROIDISM IN MUMBAI, INDIA

Autoimmunity Friday Poster Clinical

Background: The study aimed at assessing clinical, biochemical profile, quality of life (QOL), and cardiac function in Subclinical Hypothyroidism (ScHt).

Methods: 65 ScHt adults and 11 matched controls from a charitable hospital in Mumbai were invited. ScHt was defined as S.TSH≥5.0 μIU/mL, normal S.FT3, S.FT4 documented twice. Secondary causes (ablative, surgical, drugs, and pregnancy) were excluded. Clinical evaluation, thyroid function tests, lipids, QOL (PCASSE questionnaire—WHO), and cardiac time intervals (41 cases) using Color Doppler were assessed. SPSS (version10.1) was used for analysis.

Observations: The M: F ratio was 1:64 vs. 0:11. Mean age was 38.63 yrs vs. 40.2 yrs in controls. Average BMI was 26.4 kg/m2 vs. 25.0 kg/m2. Mean symptom score 9.2 in patients vs. 3.3 in controls. About 55.3% patients were goitrous (grade 1 in 23%) vs. 9% of controls. Family history was positive for T2DM (27%), hypothyroidism (15.6%), and autoimmunity (6.2%). About 20.3% were postmenopausal, and 51% premenopausal cases had menorrhagia (20%), hypomennorrhoea (11%), oligomenorrhoea (20%), infertility (10.3%), and spontaneous abortions (17.3%). Common symptoms were lethargy (63.1 vs. 18%), fatigue (69.2 vs. 40%), and weight gain (61.5 vs. 44.8%). Common signs were goiter (55.3%), coarse dry skin (36.9%), and puffiness (35.4%). Mean TSH was 10.11 μIU/mL verses 2.02 μIU/mL in controls. S.AMA and S.anti-TPO antibodies were positive in 49% and 58.5% cases. Thyroid FNAC showed Hashimoto's thyroiditis (75%). QOL was significantly reduced mainly due to physical reasons (see Table). The Apo A was low (1.125 vs. 1.527 g/L; p=2.5×10⁻⁵), and Apo B was high (1.45 vs. 0.991 g/L; p=0.001). About 22% had ST-T changes in ECG lead III. Diastolic function parameter MAPV and cardiac systolic time interval: PEP and PEP/ET ratio were increased while LVET was reduced.

Autoimmune ScHt presents in younger women in India. ScHt has significant, and hence is not literally subclinical.

1 Pediatrics, Rady Children's Hospital San Diego, San Diego, CA 2 Pediatrics, University of California San Diego, San Diego, CA Poster 127 SUBACUTE THYROIDITIS ON A BACKGROUND OF AUTOIMMUNITY

Autoimmunity Friday Poster Clinical

Subacute thyroiditis (SAT) is rarely reported in children. It is not usually associated with autoimmune thyroiditis. Neck pain or tender goiter usually follows a viral illness. Autoimmunity may be a secondary and/or transient phase. Hyperthyroidism is typically followed by euthyroidism, then possibly hypothyroidism, and ultimately euthyroid within 6–12 mo.

Chart review of 3 pediatric cases with SAT and underlying autoimmunity.

Case 1: A Hispanic female child with goiter, diagnosed at age 10.5 yrs with Hashimoto's thyroiditis, per high antithyroid antibodies, was euthyroid for 9 mo, till she became hyperthyroid, presenting with neck pain preceded by URI. Diagnosed with SAT per low iodine uptake (I-uptake) on thyroid scan, no signs of Graves' disease and negative TSI. Initially hyperthyroid, TSH<0.03 μIU/mL (0.35–5), high free-T4=2.05 ng/dL (0.9–1.4). Free-T4 normalized 10 days later, TSH stayed low, ESR=13 (1 mo postprodrome). Stayed euthyroid 4 mo, then hypothyroid 10 mo later (TSH=34.6), and levothyroxine was started. Case 2: A 14 yo Caucasian male child with Type 1 diabetes (positive GAD and ICA512) for 7 years presented with a tender thyroid preceded by a mild viral illness. Diagnosed with SAT with hyperthyroidism, per low I-uptake, raised ESR=24, and negative TSI. Initially TSH<0.03, high free-T4=1.95 ng/dL (0.71–1.85) and T3=205 ng/dL (84–179). Antithyroid antibodies remained negative since diagnosis of diabetes. One mo later was euthyroid; 2 mo after his hyperthyroidism, he was mildly hypothyroid, TSH=7.43 μIU/mL, T4=4.5 μg/dL (4.3–12.5), and became euthyroid 2 mo later. Case 3: An 18 yo Hispanic woman with pulmonary arterial hypertension presented with dyspnea, tachycardia, and painless goiter. Diagnosed with silent SAT per low I-uptake and negative TSI. Had underlying Hashimoto's thyroiditis with anti-TPO>900 and ANA 1:160. Initial TSH<0.03 μIU/mL, high free-T4=5.06 ng/dL, and T3=290 ng/dL. Methimazole used for 1 mo, stopped once euthyroid. Stayed euthyroid 8 mo, becoming hyperthyroid 1 year post-SAT, with a thyroid bruit and Graves' ophtalmopathy.

Subacute thyroiditis should be considered, even in patients with underlying thyroid or other autoimmunopathies. ESR and thyroid scan early on can aid in diagnosis.

1 Department of Surgery, Vanderbilt University Medical Center, Nashville, TN 2 Surgical Oncology, Vanderbilt University Medical Center, Nashville, TN 3 School of Law, Vanderbilt University Medical Center, Nashville, TN Poster 129 TOTAL THYROIDECTOMY FOR GRAVES' DISEASE: A CONTEMPORARY SERIES OF 165 PATIENTS

Disorders of Thyroid Function Friday Poster Clinical

Total thyroidectomy (TT) is the preferred surgical approach to Graves' disease (GD). Previous surgical series are hindered by small numbers and a mix of subtotal and TT approaches spanning several decades. Here we present the outcomes for TT at a single high-volume center.

A retrospective cohort study was conducted on 165 patients undergoing TT for GD from July 2008 through April 2012.

Mean age was 42 years (range: 17–78), and 128 patients (77%) were women. The mean BMI was 28 (range 15–59). About 81% of patients were on methimazole, 14% on propylthiouracil, and 59% remained biochemically hyperthyroid at the time of thyroidectomy. Only 3 (2%) patients received potassium iodide preoperatively. Mean operative time was 131 minutes (range 59–271). Mean gland size and blood loss were 41 grams (range 8–180) and 65 mL (range 5–1000), respectively. Median length of hospital stay was 1 day. No patient developed thyroid storm. Mean follow-up was 12 months (range 0–52). Temporary hypocalcemia developed in 50 patients (30%) persisting for >1 year in only 1 (0.6%). Temporary recurrent laryngeal nerve paresis was present in 12 (7%) patients, remaining permanent in one (0.6%). There were one tracheal injury, one hematoma, and 2 seromas. At least one complication developed in 60 (36%) patients. Female gender (Odds Ratio 2.9, p<0.05) and obesity (Odds Ratio 2.3, p<0.05) were independent risk factors for postoperative complications. There were no recurrences.

Although current ATA recommendations for the management of GD call for routine use of potassium iodide and the achievement of euthyroid state before thyroidectomy, this large series demonstrates no appreciable detriment to patient outcomes when these goals are not met. Transient hypocalcemia and hoarseness are frequent complications of TT for GD, but these resolve within six months for most patients. Female gender and obesity are independent risk factors for postoperative complications.