Abstract
Saturday, October 21, 2017
Thyroid Cancer Saturday Oral Basic 8:50 AM
THE NUCLEAR AND MITOCHONDRIAL GENOMES OF HüRTHLE CELL CARCINOMA AND ITS METASTASES
Hürthle cell (oncocytic) carcinoma is an uncommon form of thyroid cancer exhibiting follicular patterned growth, radioactive iodine resistance, and an accumulation of mitochondria. Focused DNA sequencing of small numbers of tumors has revealed an absence of alterations in known thyroid cancer driver genes. We performed whole exome sequencing on 71 samples obtained from 41 patients (34 primary tumors, 24 locoregional recurrences, and 13 distant metastases) with joint analysis of the nuclear and mitochondrial DNA for somatic mutations and DNA copy number alterations. SNaPshot genotyping and anchored multiplex PCR-sequencing was performed to validate point mutations and identify fusion oncogenes, respectively. Fluorescence in situ hybridization and flow cytometry confirmed DNA copy number in a subset of samples. In the nuclear genome, we found recurrent mutations in DAXX, TP53, NRAS, NF1, and the TERT promoter. Analysis of the mitochondrial genome revealed frequent, high variant allele fraction, disruptive mutations in complex I of the mitochondrial electron transport chain. DNA copy number analysis showed widespread chromosomal losses, culminating in a near-haploid state in a subset of tumors. Characterization of recurrent and metastatic genomes suggested that complex I mitochondrial DNA mutations are early, clonal events maintained during tumor evolution. Furthermore, primary tumors, recurrences, and metastases from individual patients exhibited closely related DNA copy number profiles, including stability of the near-haploid state over time. Recurrent somatic mutations in DAXX, NF1, TP53, NRAS, the TERT promoter, and complex I mitochondrial DNA genes are candidate driver events in Hürthle cell carcinoma. A large fraction of tumors showed a copy number signature of widespread chromosomal losses, including a near-haploid state. Evaluation of tumor evolution predicts complex I mitochondrial DNA mutations arise early during tumorigenesis and that widespread chromosomal loss is tolerated during metastatic outgrowth. We propose that the description of altered genes and chromosomes in Hürthle cell carcinoma will facilitate the development of clinical stratification and therapeutic strategies.
Thyroid Hormone Metabolism & Regulation Saturday Oral Basic 9:05 AM
MODULATION OF CHOLESTEROL AND SEX STEROID METABOLISM BY 3,5-T2 IN LIPID-LOADED PRIMARY MOUSE HEPATOCYTES
The thyroid hormone metabolite 3,5-diiodothyronine (3,5-T2) exerts thyromimetic action by influencing hypothalamic-pituitary-thyroid axis, cardiac parameters and energy metabolism in mice. Analysis of hepatic transcriptome and sex steroid profile indicated that 3,5-T2 modulates hepatic zymosterol biosynthesis and sex steroid metabolism of obese male mice on high fat diet but not in their lean litter mates. To corroborate these in vivo data we examined expression pattern genes involved in cholesterol and sex steroid metabolism in primary mouse hepatocytes without and with lipid accumulation and subsequent treatment with 3,5-T2.
Primary mouse hepatocytes were exposed to 2mM oleic acid (OA) for 24h to mimic a cell model comparable to NAFLD. Oil red O staining and measurement of triglyceride (TG) concentration confirmed intracellular lipid accumulation without impairing cell viability as determined by MTT test. Expression of 3-hydroxy-3-methylglutaryl-CoA reductase (Hmgcr), squalene epoxidase (Sqle) and 17-beta-hydroxysteroid dehydrogenase (Hsd17b7), representing important genes for cholesterol biosynthesis, was strongly increased by OA treatment. Stimulation with 0.1 and 1μM 3,5-T2 for 24h in non-lipid accumulated hepatocytes did not change expression of Hmgcr, Sqle and Hsd17b7. However, in combination with OA stimulation, 3,5-T2 decreased Hmgcr expression and slightly increased mRNA of Sqle and Hsd17b7 partially comparable with the results in liver of obese mice.
OA treatment alone decreased expression of estrogen receptor alpha (Esr1) and androgen receptor (Ar) underlining the noticeable action of lipid load on sex steroid metabolism in liver. 3,5-T2 did not change mRNA amounts of Esr1 and Ar. However, proteome analysis of mouse primary hepatocytes treated with 0.1 μM 3,5-T2 for 48h revealed altered expression of 3-beta-hydroxysteroid dehydrogenase (BHS6) and estradiol-17-beta dehydrogenase (DHB2). These results indicate a specific effect of 3,5-T2 on cholesterol biosynthesis which is exclusively observed in a model of hepatic steatosis. Independently from one another, lipid accumulation and 3,5-T2 regulate androgen and estrogen metabolism in hepatocytes.
Thyroid Hormone Action Saturday Oral Basic 9:20 AM
CHALLENGING THE ADIPOCYTE COLOR BARRIER - TR ACTIVATION ELICITS A WHITE TO BEIGE TRANSDIFFERENTIATION INDEPENDENT OF BETA-ADRENERGIC SIGNALING
An alluring possibility to combat diabetes and metabolic disease is to activate beige adipocytes, brown-like adipocytes that reside in white adipose tissue, with the capacity to conduct adaptive thermogenesis, an action often referred to as ‘beiging’. Currently, the most potent and well appreciated beiging agents are beta-adrenergic receptor (β-AR) agonists. While these agonists are capable of inducing beiging in select adipocytes, they are largely incapable of doing so in adipocytes within or derived from visceral depots or in white adipocyte cell lines. Here we show that, unlike beta-adrenergic agonism, pharmacologic activation thyroid hormone receptor (TR) signaling is sufficient to markedly induce beiging in a variety of viscerally derived white adipocytes, as well as 3T3-L1 adipose cells. TR activation is also sufficient to induce the expression of key intracellular mediators of adaptive thermogenesis, such as ATGL and HSL, lipases known to be necessary for the activation of Ucp1 mediated uncoupling and thermogenesis. Loss of β-AR signaling does not affect the ability of TR activation to elicit beiging, indicating that TR mediated beiging is independent of beta-adrenergic signaling. Finally, TR activation, unlike β-AR stimulation, appears to elicit beiging of these recalcitrant adipocytes, not via the maturation (or differentiation) of beige adipocyte precursor cells, but largely via the direct interconversion or ‘transdifferentiation’ of mature adipocytes into Ucp1+ beige adipocytes. Thus, select TR agonists can markedly elicit beiging in a fashion that appears to be mechanistically distinct from perhaps all other known beiging agents (nearly all of which require β-AR signaling), making them important tools in assessing the therapeutic potential of beige fat activation to treat diabetes and metabolic disease.
Thyroid Cancer Saturday Oral Translational 9:35 AM
RADIOIODINE REFRACTORINESS IS A MECHANISM IN THE INCREASED RECURRENCE OF PAPILLARY THYROID CANCER DRIVEN BY COEXISTING BRAF V600E AND TERT PROMOTER MUTATIONS
Coexisting BRAF V600E and telomerase reverse transcriptase (TERT) promoter mutations have been reported to be associated with aggressive behaviors of papillary thyroid cancer (PTC), but the mechanism is not clear. This study on a large cohort of patients was to evaluate the role of the genetic duet in PTC recurrence and radioiodine (RAI) avidity status. BRAF V600E and TERT promoter mutation C228T (chr5:1,295,228C>T) were examined in 1,051 PTC patients with a median follow-up time of 72 months (interquartile range 25–127). Their relationship with tumor structural recurrence and RAI refractoriness were analyzed. PTC recurrence rates were 22.6% (69/305), 20.5% (9/44), and 66.0% (35/53) in patients with BRAF mutation only, TERT mutation only, and coexisting BRAF and TERT mutations versus 8.3% (54/649) in patients with no mutation (P < 0.001, = 0.007, and <0.001, respectively). Compared with patients harboring neither mutation, HRs (95% CIs) for recurrence were 1.77 (1.22–2.58) for BRAF V600E alone; 1.38 (0.67–2.86) for TERT mutation alone; and 3.74 (2.14–6.53) for the mutation duet after adjustment for clinicopathological factors. Loss of RAI avidity was found in 72.1% (49/68), 55.6% (5/9), and 97.1% (33/34) patients with BRAF mutation only, TERT mutation only, and coexisting BRAF and TERT mutations versus 30.2% (16/53) patients without mutation (P < 0.001, = 0.137, and <0.001, respectively). These corresponded to ORs (95% CI) of 5.63 (2.49–12.72), 2.18 (0.39–12.25), and 127.69 (11.45–1423.89), respectively, after adjustment for patient age and sex. Similar results were obtained when only the conventional PTC was analyzed. BRAF V600E mutation only, but not TERT mutation only, is independently significantly associated with recurrence and loss of RAI avidity; coexisting BRAF V600E and TERT promoter mutations were associated with the highest recurrence and RAI refractoriness. The high RAI refractoriness is a mechanism of the effect of the genetic duet on PTC recurrence.
Thyroid Cancer Saturday Oral Clinical 8:50 AM
CLINICAL VALIDATION OF THYROSEQ V3® PERFORMANCE IN THYROID NODULES WITH INDETERMINATE CYTOLOGY: A PROSPECTIVE BLINDED MULTI-INSTITUTIONAL VALIDATION STUDY
To determine the diagnostic accuracy of ThyroSeq molecular testing for cytologically indeterminate thyroid nodules. ThyroSeq® version 3 (v3) genomic classifier (GC) assesses FNA sample cellularity and utilizes next-generation sequencing (NGS) of adequate samples to test for mutations, fusions, gene expression, and copy number variations in 112 thyroid-related genes. Using an algorithmic approach, the results are reported as negative (benign) or positive (likely malignant). A prospective, blinded study of ThyroSeq v3 was carried out at 10 medical centers with 805 patients enrolled. The surgical pathology slides were blindly reviewed by a panel of expert pathologists. The primary outcome was diagnostic accuracy of ThyroSeq v3 test for Bethesda III and Bethesda IV nodules, with NIFTP included in the malignant group as nodules requiring surgery. Of the 286 cytologically indeterminate and surgically excised nodules, 206 (72%) were benign, 69 (24%) malignant, and 11 (4%) NIFTP. A total of 257 (90%) nodules (154 Bethesda III, 93 IV, and 10 V) had sufficient cellularity and thyroid cell proportion for informative analysis. Overall, 61% of the Bethesda III and IV nodules were called negative (benign) and 39% positive by ThyroSeq v3 GC. In Bethesda III nodules, the test yielded a sensitivity of 91%, specificity of 85%, NPV 97%, and PPV 64%, with a malignant + NIFTP prevalence of 23%. In Bethesda IV nodules, the test had a sensitivity of 97%, specificity of 75%, NPV 98%, and PPV 68%, with malignant + NIFTP prevalence of 36%. The 2–3% residual cancer probability in the test-negative nodules is similar to that of benign cytology, and there were 3 PTC and 1 FTC among 4 false-negative cases. Among 33 false-positive cases, 70% were follicular or oncocytic adenomas on pathology, none had a molecular signature of high-risk cancer, and 94% showed clonal alterations indicating they were neoplasms, not hyperplasia. In this prospective, blinded, multi-center study, ThyroSeq v3 appears to be more sensitive and less specific than its prior version. The high negative call rate and low residual cancer risk could help to avoid diagnostic surgery in as many as 60% of patients with cytologically indeterminate Bethesda III and IV nodules.
Thyroid Nodules & Goiter Saturday Oral Clinical 9:05 AM
DEVELOPMENT AND VALIDATION OF CLASSIFIERS TO ENHANCE THE AFIRMA GENOMIC SEQUENCING CLASSIFIER PERFORMANCE AMONG HüRTHLE CELL SPECIMENS
Most Hürthle cell dominant Bethesda III+IV thyroid nodules undergo diagnostic surgery, yet most are histologically benign. The Gene Expression Classifier (GEC) provided these samples a high NPV, but most were GEC suspicious. To maintain a high NPV while providing more benign results, we built two dedicated classifiers to work with the core Genomic Sequencing Classifier (GSC), which uses RNA sequencing and machine learning algorithms to identify benign nodules preoperatively with overall 91.1% sensitivity and an improved 68.3% specificity. A Hürthle cell classifier was developed using 1,408 nuclear and mitochondrial genes to differentiate Hürthle cytology specimens (H+) from non-Hürthle specimens (H-). A separate Hürthle neoplasm classifier was developed using 2,041 genes and a chromosome-level loss-of-heterozygosity statistic built from 189,731 genomic variants to differentiate Hürthle neoplastic specimens (N+) from non-neoplastic Hürthle specimens (N-), only among H+ specimens. H+N+ and all H- specimens are subject to the canonical GSC cutoff, while an adjusted threshold is used only for H+N- specimens. We applied this process in a blinded fashion to the prospective, multicenter, and blinded Bethesda III+IV samples that originally validated the GEC, of which 191 had sufficient remaining RNA.1 MTC, 3 BRAF V600E+ PTC, and 1 with inadequate follicular cell content were identified by upstream classifiers, leaving 186 specimens for GSC core classifier testing, of which 37 (20%) resulted H+; among these, 16 were classified as Hürthle non-neoplastic (N-). Among these H+N- specimens, 9 (56%) had canonical benign GSC scores and would result GSC benign by either threshold. However, the Hürthle-adjusted threshold rescued the other 44% to a benign result. Among the 26 Hürthle cell adenomas and carcinomas, the final GSC sensitivity for malignancy identification was 88.9%, and the specificity to identify benign lesions was 58.8%, a 47% absolute improvement of specificity above the previous GEC. The improved overall GSC specificity results from improvements among both Hürthle and non-Hürthle Bethesda III+IV specimens. GSC testing of both Hürthle and non-Hürthle nodules may safely reduce unnecessary diagnostic surgery.
Thyroid Cancer Saturday Oral Clinical 9:20 AM
EMERGENCE OF V804M RESISTANCE GATEKEEPER MUTATION IN SPORADIC MEDULLARY THYROID CARCINOMA PATIENTS TREATED WITH TKI TYROSINE KINASE INHIBITORS
Advanced medullary thyroid cancer patients whose disease is progressing are treated with vandetanib or cabozantinib or both sequentially. Ultimately, resistance emerges in these patients complicating subsequent therapeutic choices. RET and RAS are known somatic mutations in many of these patients. RET V804M mutation has been described as one mechanism of resistance in vitro but to date confirmation in patient tumors is lacking. We examined cell free DNA (cfDNA) from advanced medullay thyroid cancer patients for the presence of RET V804M mutations. We prospectively examined cfDNA isolated from 16 medullary thyroid cancer patients wtih advanced disease for the presence of RET M918T and V804M mutant DNA ddPCR. These patients all had molecular testing for alterations on tissue prior to therapy confirning somatic RET M918T status. Vital status and response to therapy were recorded. 16 progressing medullary thyroid cancer patients had both molecular testing done on their tissue prior to exposure to cabozantinib or vandetanib (TKI) and cfDNA analysis postTKI exposure. 12/16 were male (75%). 13/16 (81.25%) patients had exposure to either cabozantinib or vandetanib (TKIs) or both. Of the 13 patients treated with TKIs, RET V804M cfDNA was detected in 8 patients. All 8 of these patients had evidence of progression at the time of sampling for the RET V804M mutation and 3 subsequently died from their disease. In all cases RET V804M cfDNA amount did not exceed RET M918T cfDNA levels. This is the first report of emergence of RET v804m mutation in humans after TKI exposure. Measurement of cfDNA can be an important adjunct to the treatment of these advanced medullary thyroid cancer patients. The discovery of this mutation as a possible mechanism of resistance may help direct future therapy.
Thyroid Cancer Saturday Oral Clinical 9:35 AM
A MULTICENTER, RANDOMIZED, OPEN-LABEL, PHASE 2 TRIAL OF DONAFENIB IN PROGRESSIVE LOCAL OR METASTATIC RADIOIODINE-REFRACTORY DIFFERENTIATED THYROID CANCER: A PRELIMINARY SHORT-TERM REPORT OF EFFICACY AND SAFETY
Standard treatments for differentiated thyroid cancer including thyroidectomy, selective radioiodine (RAI) therapy and suppression of thyroid-stimulating hormone. While, 20–50% of patients with local advanced lesions or metastatic disease will become refractory to RAI therapy which defined as radioiodine refractory differentiated thyroid cancer (RAIR-DTC). For these patients, treatment options remain limited. Donafenib, a new oral multikinase inhibitor showed antitumor activity by targeting Raf kinase and VEGF receptor in a phase I dose-escalation study. In the present study, we evaluated the short-term efficacy and safety of Donafenib in patients with RAIR-DTC.
A randomized, open-label, phase 2 trial was conducted at 18 hospitals in patients aged 18 years or older with RAIR-DTC in China. Totally, 23 patients were enrolled in this study and randomly assigned into 2 groups: 1) Donafenib 200mg orally twice daily, 2) Donafenib 300mg orally twice daily. The primary endpoint of this study was serum thyroglobulin (Tg) concentration and disease control rate (DCR) based on RECIST 1.1 criteria. The secondary endpoint was the safety of Donafenib. By the end of July, 10 pts were eligible for a minimum of 8-week's assessment. The Tg levels presented a decreased trend after 8 weeks of Donafenib treatment in 7 patients with Tg available for evaluation, which represented a biochemical response. The mean decline of diameter of target lesions (TL) in 10 patients was 15.9% after 8 weeks of Donafenib treatment. 1 patient (1/10) achieved partial response according to RECIST 1.1 criteria and 9 patients (9/10) with stable disease, with 100% DCR. The most common adverse events included hand-foot-skin reactions, hypertension and alopecia, which accounted for 90%, 40% and 40% of the cases, respectively. No AE beyond grade 3 and severe AE related to Donafenib was observed during the treatment.
Donafenib showed safe antitumor activity in RAIR-DTC patients within the first 8 weeks of treatment.
Thursday, October 19, 2017
Disorders of Thyroid Function Thursday Poster Clinical
IMPACT OF LAPAROSCOPIC SLEEVE GASTRECTOMY ON THYROID FUNCTION PROFILES IN CHINESE OBESE PATIENTS
There exists close relationship between thyroid function disturbances and obesity. Laparoscopic sleeve gastrectomy (LSG) is an effective bariatric surgery in weight loss and treating obesity-associated comorbidities. Few studies involve in the alteration of thyroid hormones after bariatric surgery with inconsistent results. This study aimed to investigate the effects of LSG on thyroid function profiles in Chinese obese patients. A retrospective study was performed in seventy-five obese patients (male: female = 34:41) who underwent LSG. Thyroid function profiles (TT4, FT4, TT3, FT3 and TSH), anthropometric data, and glucose-lipid metabolism parameters were measured at baseline, 3, 6 and 12 months after LSG. Correlations between TSH with other parameters were evaluated. The subjects were divided into three groups: normal TSH (0.35–2.5 mU/l), higher-normal TSH (2.5–5.0 mU/l) and subclinical hypothyroidism (SCH, TSH >5.0 mU/l). In all individuals, FT3, FT4, TT3, TT4 and TSH levels decreased at 3–12 months after LSG (all P < 0.01 except at 12 months, FT4 and TSH decreased without significant difference). 9.3% (7/75) patients had SCH at baseline and 71.4% of them had normal/higher-normal TSH levels at 3 months after LSG. And 68.4% of higher-normal TSH individuals (36% of all the subjects, 27/75) reverted to normal.
TSH levels were positively correlated with body mass index (BMI), fasting insulin (FINS) and fasting C-peptide (FCP) at baseline and 3–12 months after LSG (P < 0.05 or P < 0.01). There was a significant positive association between TSH decrease with FINS and FCP reductions at 3 and 6 months (P < 0.05 or P < 0.01), with the increase of high density lipoprotein at 3 months (P < 0.05). TSH decrease at 3-12 months was also positively correlated with TSH at baseline (P < 0.001 or P < 0.05).
It showed that the decrease of weight, BMI, FINS, FCP and TSH were more significant in SCH/higher-normal TSH group than normal TSH group. TSH is closely related to BMI and glucose-lipid metabolism. We speculate that elevated TSH levels or even SCH in obese subjects may be compensatory as for the abnormal fat accumulation but not real hypothyroidism. And LSG could generally correct thyroid function profiles and treat SCH in obese patients.
Disorders of Thyroid Function Thursday Poster Clinical
L-THYROXINE IN AN ORAL LIQUID OR SOFTGEL FORMULATION ENSURES MORE NORMAL SERUM LEVELS OF FREE T4 IN PATIENTS WITH CENTRAL HYPOTHYROIDISM
L-thyroxine therapy of central hypothyroidism (CH) is guided by measurements of serum free T4 (FT4), which should be above the midnormal range value (MNRV). In some countries, novel formulations of oral L-thyroxine (liquid or softgel) are available further to the classic tablets. The intestinal absorption of either novel formulation is greater than tablets in patients with primary hypothyroidism. Our observation of six patients with isolated CH and serum FT4 below MNRV under stable adequate doses of tablet L-thyroxine (median 1.51 μg/Kg/day bw), prompted us to switch them to liquid (n = 4) or softgel (n = 3) L-thyroxine at the same dose, and verify whether FT4 increased above MNRV. A seventh patient with FT4 above MNRV was enrolled because she wanted a “more modern formulation”. Post-switch FT4 was measured at least twice with the same kit as pre-switch FT4. In the first six patients, post-switch FT4 averaged 13.0 ± 1.6 pg/ml compared to 10.4 ± 1.8 pre-switch FT4 (P = 0.00026), with 11/13 (85%) measurements above MNRV compared to 0/20. In the liquid or softgel L-thyroxine group, post-switch FT4 averaged 13.1 ± 1.6 vs 10.6 ± 0.9 pg/ml pre-switch (P = 0.0004) or 12.9 ± 2.1 vs 10.3 ± 2.4 (P = 0.048). In the seventh patient (switched to liquid L-thyroxine), averages were 18.3 vs 15.2 pg/ml and proportions 4/4 vs 2/2. In conclusion, in CH patients oral liquid or softgel L-thyroxine administered at the same doses as tablet L-thyroxine ensures target serum FT4 levels above MNRV that tablet L-thyroxine may miss. In turn, this performance confirms the more favorable pharmacokinetics profile of either novel formulation compared with the tablet formulation.
Thyroid & Development Thursday Poster Basic
EVALUATION AND QUALITY ASSURANCE OF EFFECTIVENESS OF AN AOTA RECOGNISED THYROID TRAINING PROGRAM FOR PRIMARY CARE PHYSICIANS IN INDIA
Thyroid disorders are common in India, with an estimated 42 million affected by either hypothyroidism or hyperthyroidism. Equipping the primary care physicians (PCPs) on a robust and standardized pan India capacity building programme was the need of the hour, to increase clinical awareness, diagnose and treat these cases at the primary level thereby reducing the load of the overburdened tertiary centres. Certificate Course in Management of Thyroid Disorders was started in 2014 in collaboration with an academic partner, Chellaram Diabetes Institute and an unrestricted educational grant from GlaxoSmithKline Pharmaceuticals. The curriculum contextualized by the academic partner was vetted by the team of national experts and delivered by specialists trained in its standardized delivery. The course has received SAFES accreditation for 2016–17 and endorsement from AOTA for 2016–25. To ensure quality and standardized delivery of training, the course was supported by a strong monitoring and evaluation mechanism conducted during each of the modules utilizing the services of Observers who specialized in public health, and an evaluation conducted before and after conduct of the course. This four month executive, on job training program so far has trained nearly 2500 doctors in its three cycles being implemented in 35 centres in India. The Observers confirmed 93% of the trainers adhered to guidelines for session conduction. 100% of participants agreed that the curriculum content enhanced their knowledge and added value to their skills in the detection and management of thyroid disorders. According to 84% participants case studies, videos and group activities were extremely valuable for discussion on real life clinical scenario. By ensuring the quality assurance through a robust monitoring mechanism, we have been able to deliver the course in a standardized pattern across the country, which could be of immense value for other LMIC countries, as well as help in the development of programs at global level.
Thyroid Cancer Thursday Poster Basic
THE STUDY OF DEDIFFERENTIATION PATTERN OF DTC: IS PDTC THE INTERMEDIATE STATE FROM DTC TO ATC?
Most of PDTC (Poor differentiated thyroid cancer) and ATC (Anaplastic thyroid cancer) are originated from DTC (Differentiated thyroid cancer) through dedifferentiation process of which pattern and mechanism remains unclear. One of the controversial points is whether PDTC is the intermediate form of DTC dedifferentiating toward ATC? Although progressive accumulation of gene mutations were observed in both of PDTC and ATC, the direct evidence of association between DTC, PDTC and ATC is still lacking. Whole exome sequencing was performed in selected samples (primary PTC lesion, para-cancer normal tissue, metastatic lymph nodes of PTC, PDTC and ATC) from a special case with PTC in primary lesion and PTC, PDTC, ATC in metastasis lymph nodes simultaneously. Sequencing data were analyzed by bioinformatics methods and were validated in clinical tissue samples by sanger sequencing. Totally, 186 nonsynonymous mutations were identified in malignant samples. Among them, 151 mutations (ubiquitous) could be found in primary tumor while the other 35 mutations (non-ubiquitous) exist in metastatic loci. Mutational spectrums were compared between different metastatic samples. Then, in terms of gene mutation, following characteristics were observed: 1.PDTC and ATC were associated with PTC-LN2 but not PTC-LN1; 2. Most of non-ubiquitous mutations of ATC were shared with PDTC (7/9); 3. Except two mutations that co-owned simultaneously by PTC-LN2, PDTC and ATC, no other associations were found between ATC and PTC-LN2 samples. In addition, we have found seven mutations (five PDTC/ATC shared mutations and 2 ATC private mutations), including TP53 p.N107_S108delinsX, that may potentially related with the process of DTC dedifferentiation.
Dedifferentiation process of DTC-PDTC-ATC could be stepwise. PDTC is an important intermediate status between DTC and ATC. Cumulative effect of one key mutation and several low-frequency mutations was a possible mechanism.
Thyroid Cancer Thursday Poster Translational
LENVATINIB AND ANTI-PD-1/PD-L1 CHECKPOINT INHIBITOR COMBINATION THERAPY REDUCE TUMOR VOLUME AND IMPROVE SURVIVAL IN AN ORTHOTOPIC IMMUNOCOMPETENT MURINE MODEL OF ANAPLASTIC THYROID CANCER
Lenvatinib, a multitargeted tyrosine kinase inhibitor, has shown promise in treating patients with advanced thyroid cancer. Unfortunately, emergence of resistance is common. Checkpoint inhibitors targeting programmed cell death protein (PD) and its ligand PD-L1 have proven effective in many solid tumors with an immunosuppressive microenvironment, including some patients with thyroid cancer. We hypothesized that the combination of lenvatinib with immunotherapy would improve the magnitude and duration of tumor shrinkage, and minimize development of resistance in a murine model of anaplastic thyroid cancer (ATC).TBP-3743-GFP murine ATC cells (BRAFV600E/WT, TP53−/−) were orthotopically implanted into the left thyroid lobe of thirty-six six-week old female syngeneic B6129FSF1/J mice, as previously described. On post-implantation day 6, mice were randomized to vehicle, lenvatinib 30mg/kg by oral gavage, 10 mg/kg anti-PD-1 or anti-PD-L1 antibody by intraperitoneal injection, or combination therapy with lenvatinib and either anti-PD-1 or anti-PD-L1 antibody. Tumor volume and survival were measured, tumor cells were isolated, and immunohistochemistry and flow cytometry for various immune cell markers were performed. The experiment was repeated once. Lenvatinib and anti-PD-1 or anti-PD-L1 combination therapy led to 57.5% and 47.9% tumor growth inhibition compared to control, respectively, significantly more than anti-PD-1 (13.1%), anti-PD-L1 (15.4%), and lenvatinib (19.2%) monotherapies. Mice survived for a median of 13.5 (control), 18.5 (lenvatinib), 14 (anti-PD-1), 14.5 (anti-PD-L1), 28 (lenvatinib + anti-PD-1), and 22.5 days (lenvatinib + anti-PD-L1). While lenvatinib alone appeared to increase tumoral myeloid-derived suppressor cell-like (MDSC) populations compared to control, combination therapy led to increases in tumor-associated macrophages (TAM) and cytotoxic T-cells, and decreases in MDSC-like cells. Combination therapy with lenvatinib and anti-PD pathway antibodies leads to improved tumor shrinkage and survival compared to monotherapy in an orthotopic immunocompetent murine model of ATC, and is associated with significant increases in TAM and decreases in tumoral MDSC-like cells.
Thyroid Cancer Thursday Poster Translational
EVALUATION OF BRAFV600E LEVELS IN CELL FREE DNA (CFDNA) AS A BIOMARKER OF RESPONSE IN BRAF V600E MUTATED RADIOACTIVE IODINE REFRACTORY (RAIR) DIFFERENTIATED THYROID CANCER (DTC) TREATED WITH DABRAFENIB ALONE OR IN COMBINATION WITH TRAMETINIB
While cfDNA has emerged as a biomarker of great potential in several malignancies, its role in DTC has not been prospectively studied. As serum thyroglobulin (Tg) is a poor therapeutic marker of response in RAIR DTC treated with BRAF inhibitor (BRAFi) dabrafenib +/- MEK inhibitor (MEKi) trametinib, we sought to evaluate the correlation between levels of BRAF V600E mutation in cfDNA and radiographic response in these patients (pts) treated dabrafenib +/- trametinib, as part of a randomized multicenter phase II study of dabrafenib versus dabrafenib + trametinib in BRAF mutated DTC. Plasma samples for cfDNA testing were collected on day 1 of each cycle (cycle length = 4 weeks) for the first 6 cycles and every other cycle thereafter, up to and including time of progression. CT or MRI scans were done at baseline and day 1 of all odd cycles. Treatment response was assessed using RECIST v1.1 criteria. Droplet digital polymerase chain reaction (ddPCR) was performed to detect BRAF V600E in cfDNA.Of 40 pts no longer on treatment at data-cut off, 37 were evaluable for response, of whom 20 have had quantification of BRAF V600E by ddPCR completed to date. 7/20 (35%) pts had detectable levels of V600E at baseline, and all 7 (100%) had undetectable V600E levels by cycle 3 day 1 of treatment. 5/7 (71%) patients had partial response (PR) and 2/7 (29%) had stable disease (SD) as best response. In 2 of the pts with radiographic PR as best response, there was a greater than two-fold increase in corresponding Tg levels from baseline, while V600E levels at the same time point were undetectable. 4/7 pts went off study due to PD and had plasma samples available for evaluation of V600E cfDNA levels at or around PD. V600E cfDNA levels became detectable at or around PD in 3/4 (75%) pts. A pt who had clinical evidence of PD leading to death, despite radiographic PR 4 weeks prior, had detectable V600E cfDNA levels around clinical progression. BRAF V600E in cfDNA may help predict treatment response in BRAFi+/-MEKi treated RAIR DTC.
Thyroid Cancer Thursday Poster Translational
THE LANDSCAPE OF SOMATIC MUTATIONS OF MEDULLARY THYROID CANCER AS ASSESSED BY NEXT GENERATION TARGETED SEQUENCING*
Sporadic Medullary Thyroid Carcinomas (sMTC) harbor RET and RAS somatic mutations in about 40% and 10% of cases, respectively. of cases. Still 50% of sMTC are orphans of an oncogene driver mutations. Despite the high sensitivity, so far also next generation sequencing (NGS) failed in finding other genetic alterations in RET and RAS negative cases. Aim of this study was to discover by NGS the genomic landscape of those cases previously found to be RET negative by direct sequencing (DS). Forty-three sMTC previously identified as RET negative by DS were targeted sequenced using a NGS panel containing the entire coding region of RET and RAS genes and hot spot regions in the AKT1, β-catenin, CHEK2, PIK3CA, PPM1D, PTEN, TP53 and TSHR genes. Additional 16 RET positive MTC at DS were submitted to NGS as control. Nineteen/45 (42.2%) RET negative cases were confirmed to be negative by NGS for all mutations analysed. In the remaining 26 cases, we found 6/45 cases (13.9%) harbouring a single RET mutation (4 M918T, 1 C620R, 1 D898_E901del) and 14/43 (32.5%) a single RAS mutation (13 in HRAS and 1 in KRAS). Five/45 (11.1%) cases showed the simultaneous presence of 2 or more mutations (1 KRAS+RET; 1 HRAS+RET+TSHR; 2 double RET mutations and 1 TSHR+TP53). Finally, 1/45 (2.3%) case harbored the PPMD1 R458 * mutation. The 16 RET positive controls were confirmed by NGS as single RET mutated cases. The mean allele frequency of RET mutations in the RET negative cases (29.6%) was significantly lower than in controls (49%) (p = 0.026). NGS is able to identify other RET positive cases not detected by DS because of the low allelic frequency. RET and RAS mutations are confirmed to be the two major drivers in sMTC but still 40% of cases remain negative. The role of rare mutations in TP53, TSHR and PPM1D genes need to be further investigated.
Thyroid Cancer Thursday Poster Clinical
INCREASED RISK OF THYROID DIFFERENTIATED CANCER IN A POPULATION EXPOSED TO IONIZING RADIATION FOR CONGENITAL HEART DISEASE IN VERY EARLY CHILDHOOD.
Radiation exposure of the thyroid at a young age is a known risk factor for the development of thyroid differentiated cancer: the younger the age, the higher the risk. In congenital heart diseases (CHD), diagnostic and therapeutic interventional cardiology procedures are performed in the early days of life, and often repeated in childhood, exposing the thyroid to x-rays. The aim of this study was to evaluate prevalence of differentiated thyroid cancer in this specific very high risk population. Thyroid screening was proposed to adult patients with complex CHD who were exposed in the early childhood to repeated catheterizations and radiation. Thyroid screening consisted in ultrasonography (US) and blood test assessing free T4, free T3 and TSH. Seventy-one patients completed the study, 71% men, 41% tetralogy of Fallot, 28% coarctation of the aorta, 11% transposition of the great vessels and 20% other complex CHD. Mean thyroid dose received was estimated at 33.8 ± 19.3 mSv, mean number of catheterizations per patient was 4.9 ± 2.8. Twenty patients (62%) were <1 year at first catheterization, 8 patients (24%) between 1-5 years, 5 patients (15%) between 5-16 years. Ten patients had abnormal thyroid function: 4 were hyperthyroid and 6 hypothyroid. However, 9 patients were treated by Amiodarone.
Among the 45 US performed: 25 were normal (55%), 9 presented thyroid nodules >5 mm (20%), 3 multinodular goiter (7%), 2 simple goiter (4%) and 3 hypotrophy (7%).
Three patients had differentiated thyroid cancer (7%), diagnosed at 30.3 ± 6 years. One pT3mNx, 74 mm, one pT3N1, 55mm, with 3 cervical lymphadenectomies, and both pulmonary and bone metastasis 11 years after diagnosis and one pT1bN0, 14mm.
Incidence of thyroid differentiated cancer was 51.7 per 100000 person-year and standardized incidence ratio was 1.74 (95%IC [0,35; 5,08]). This is the first study done in an exhaustive population exposed to radiations in the first days of life. There was an increased risk of differentiated thyroid cancer, compared to incidence in general population. Our study contributes to confirm thyroid radiosensitivity and increased risk for exposures that occur at younger ages.
Thyroid Cancer Thursday Poster Clinical
ROSETTAGX REVEAL THYROID MIRNA CLASSIFIER IS A MORE SPECIFIC TEST THAN AFIRMA GENE EXPRESSION CLASSIFIER
Molecular tests are increasingly used to triage patients with indeterminate thyroid nodules on FNA for surgery and/or follow-up. Currently the Afirma Gene Expression Classifier (AGEC) is the most frequently utilized test, requiring 2 additional FNA passes, a specific preservative solution and refrigeration. AGEC has been associated with low specificity and PPV. RosettaGX Reveal (Reveal) is a microRNA-based test that classifies indeterminate thyroid nodules into benign, suspicious for malignancy (SUSP) or positive for medullary carcinoma utilizing stained FNA smears. We compare the performance of Reveal with AGEC in a cohort of indeterminate thyroid FNAs. Reveal was performed in a blinded fashion on 82 indeterminate samples with AGEC and surgical pathology results. One specimen failed QC, thus 81 were analyzed. The final histologic diagnosis was benign/NIFTP (n = 63) and malignant (n = 18). 54 FNAs were classified as Bethesda III, 26 as Bethesda IV and 1 medullary carcinoma FNA as Bethesda V. Of the 18 malignant samples, 14 were classified correctly as SUSP by Reveal and 17 by AGEC. Of the 63 benign/NIFTP samples, 33 were correctly classified by Reveal but misclassified by AGEC, while 1 was correctly classified by AGEC and misclassified by Reveal. Of the remaining samples, 24 were misclassified as SUSP and 5 were correctly classified as benign by both tests. Thus the specificity of Reveal in this cohort is 60% [95% CI 47-72]. Of the 26 benign Hurthle cell lesions, 17 were correctly classified as benign by Reveal while AGEC classified only 1 correctly as benign and misclassified 25 as SUSP. In this study Reveal outperformed AGEC (64.2% vs 28.4% respectively correct classification; p = 0.000013), particularly in Hurthle cell lesions.
Thyroid Cancer Thursday Poster Clinical
TREATMENT EXPERIENCE OF ANAPLASTIC THYROID CARCINOMA WITH LENVATINIB
Anaplastic thyroid cancer (ATC) is one of the most aggressive and deadly human malignancies. Its mortality approaches 100%, with average survival rate of 4-6 months after diagnosis. ATC tumors poorly respond to current multimodal therapies including surgery, chemotherapy and radiation therapy. Lenvatinib is a thyrosine kinase inhibitor, targeting VEGF receptors, FGF receptors, PDGF receptors, KIT and RET. Information on its effect in humans with ATC is scarce. In this study, we describe our experience treating our patients with ATC with lenvatinib and their outcome. This is a case series of four patients diagnosed with ATC at City of Hope Medical Center from 1/2006 through 8/2017. Patients had first undergone standard treatments including surgical resection, chemotherapy and radiation therapy without success. They then accepted and consent to undergo treatment with lenvatinib off label. The data collected included demographic and clinical characteristics, treatments and outcomes. Progression-free survival was defined as the period between the beginning of treatment with lenvatinib and imaging study recorded indicating disease progression or death. Overall survival was defined as the period between diagnosis of ATC until end of the study or death. We studied 4 patients with ATC who had undergone total thyroidectomy, chemotherapy and radiation therapy without success, except one patient who was not a surgical candidate. Mean age at diagnosis was 71.5. Two patients were males. Three out of four patients had favorable response to lenvatinib treatment with decrease in the size and hypermetabolic activity of their lesions. Progression-free survival were 27 months, 9 months and 8 months for patients who had a favorable response to therapy. Overall survival rates from the time of diagnosis were 11 years, 29 months, 24 months and 2 months. For all patients, the dose had to be decreased due to side-effects. The most common side-effect was hypertension. In our experience, most patients with anaplastic thyroid cancer with persistent disease after surgery and chemotherapy and radiation had favorable outcome with lenvatinib therapy, with improved survival.
Thyroid Cancer Thursday Poster Clinical
ASSOCIATION BETWEEN BODY MASS INDEX AND SEVERITY ACCORDING OF CLASSIFICATION OF THYROID CANCER
Obesity is associated with aggressive pathological features and poor clinical outcomes in breast and prostate cancers. However, the associations between excess weight and prognostic factors for thyroid cancer are uncertain. This study aimed to evaluate the associations between body mass index (BMI) and severity according of classification of thyroid cancer. Retrospective analysis of 4558 patients with thyroid cancer was performed. Patients were grouped according to BMI (underweight, normal weight, overweight and obesity)-based World Health Organization standardized categories. Clinicopathological factors were analyzed and compared between normal and other groups. According to the results, 3852 patients were women (84.5%) and mean age was 55.07 years. 4385 patients (96.2%) were diagnosed with PTC. FTC were 143 (3.1%), MTA ware 24 (0.5%), ATC were 5 (0.1%). There were no significant associations between BMI quartiles and Multifocality, cervical lymph node metastasis, or distant metastasis. Higher BMI were significantly associated with extrathyroidal extension of PTC (P < 0.001). And higher BMI were significantly associated with advanced TNM stage. (P = 0.005) Increased BMI might elevate the risks of aggressive clinicopathological features of PTC, such as extrathyroidal invasion and advanced TNM stage. However, there were few cases except for PTC, which made it difficult to find statistically significant results. To confirm this result, further studies with long-term follow-up and more patients are required.
Thyroid Cancer Thursday Poster Clinical
RISK FOR THYROID CANCER RECURRENCE IS HIGHER IN MALE THAN IN FEMALE PATIENTS EVEN WHEN CORRECTED FOR STAGE AT PRESENTATION
There are differences between men and women regarding presentation, management and outcomes of differentiated thyroid cancer (DTC). Our objective was to analyze sex-related differences in a large Canadian cohort and asses if differences persist after correction for stage. Canadian Collaboration Network for Cancer of the Thyroid (CANNECT) is a collaborative registry to describe patterns of care for thyroid cancer; here we present interim data on 6 participating centers. We included patients with DTC diagnosed at age 18 or older between 2000 and 2010. We compared men and women patients with respect to presentation, management and outcomes, specified per AJCC stage. We included 2526 patients, 585 (21%) men and 2177 (79%) women. Distribution across AJCC stages I, II, III and IV was 71%, 13%, 12% and 4% for women and 52%, 13%, 21% and 14% for men, respectively (P < 0.001, Chi Square). There was no difference in age at presentation or radioactive iodine ablation (RAI), specified per stage, between sexes. Follow-up duration did not differ between men (mean 7.7 years SD ± 3.9) and women (mean 7.7 years SD ± 4.0) patients. Overall recurrence rate was 2.6 % (n = 52) for women and 9.7% (n = 47) for men (P < 0.05). Recurrence rate specified by AJCC stage and sex was as follows: stage I 1.8% (women) and 7.5 % (men) (P < 0.05); stage II 1.2 % and 7.5% (P < 0.05), stage III 3.1% and 11.0% (P < 0.05), stage IV 24.6 % and 22% (P = NS). Our study confirms that the risk for recurrence of DTC is higher in men than in women patients. This difference persists when correcting for stage of presentation (except for Stage IV). It needs to be determined if this sex difference in recurrence risk should influence follow-up intensity and/or duration. The underlying biology still needs to be elucidated.
Thyroid Cancer Thursday Poster Clinical
IDENTIFICATION OF PAPILLARY THYROID CANCER MICROMETASTASES IN LYMPH NODES USING A MULTILEVEL SECTIONING PROTOCOL AND IMPACT ON RISK OF RECURRENCE
Current guidelines state that patients with intermediate-risk papillary thyroid cancer (PTC) should be considered for remnant ablation (RA). One criterion classifying patients as intermediate-risk is the presence of micrometastasis in ≥5 lymph nodes (LN). Standard, wide-cut sectioning of LN specimens may preclude evaluation of all LNs present within the tissue block, and thus potentially overlook metastatic foci. There is no standard protocol for LN sectioning, and reported rates of micrometastases vary. Here, we examine whether a multilevel, fine-cut sectioning protocol increases detection of micrometastases, thereby influencing the risk of recurrence (ROR). A retrospective review was conducted of all cases from January 2010 - August 2015 with ≥5 LNs excised during thyroidectomy, and ≤4 LNs positive for PTC. Data from prior conventional sectioning was collected. Multilevel sectioning was performed on original tissue blocks, with a slice thickness of 0.18mm. A senior thyroid pathologist reviewed the slides and total LNs identified and LNs positive for micrometastasis were recorded. 17 cases were reviewed. In 10 cases, multilevel sectioning did not detect additional LNs. In 7 cases, there was a significantly increased number of LNs detected with multilevel compared to conventional sectioning (20.7 LNs ±10.7 SD vs. 18.3 LNs ±10.2 SD, respectively; p = 0.02, paired t-test). In total, multilevel sectioning identified 17 additional LNs; of these, 9 were positive for PTC. Metastatic foci within newly-identified positive LNs were larger than foci within known positive LNs (7.9 mm ±3.8 SD vs. 4.8 mm ±4.6 SD, respectively), but this difference was not significant (p = 0.18). In 3 cases, the revised total of positive LNs was ≥5 (4 to 6, 3 to 6, 4 to 5 positive LNs), thus upstaging these cases from low to intermediate ROR. Compared to conventional sectioning, multilevel sectioning significantly increased the number of LNs identified, and detected metastatic foci in LNs which would otherwise remain un-examined. The increased number of positive LNs identified may alter ROR and potentially affect recommendations for RA. The cost and time implications of an intensified sectioning protocol warrant further study.
Thyroid Cancer Thursday Poster Clinical
CHARACTERISTICS OF FOLLICULAR VARIANT PAPILLARY THYROID CARCINOMA IN A PEDIATRIC COHORT
The 2015 ATA guidelines for children with thyroid cancer recommend total thyroidectomy for nearly all patients with differentiated thyroid carcinoma (DTC). In adults, there are several DTC variants, including non-invasive subtypes of follicular variant papillary thyroid carcinoma (fvPTC), that are at low risk for metastasis and persistent or recurrent disease. For these variants, lobectomy may suffice to achieve remission, but it is unknown if this is true in pediatrics. We describe the clinical and histopathological features of fvPTC in a pediatric cohort. A single center, retrospective review was performed in children <19 years of age with DTC who underwent surgery between 1/2010 and 7/2015. Cases were selected for histopathology, ultrasound, and medical record review if the pathology report indicated follicular variant architecture within the primary tumor. On review, fvPTC was defined as exclusively follicular or predominantly follicular and focal solid growth, complete lack of well-formed papillae, and nuclear features of PTC. Eighteen patients met criteria for diagnosis of fvPTC. All had undergone thyroidectomy or lobectomy followed by completion thyroidectomy. Most (12, 67%) had unilateral nodules on pre-operative ultrasound. On histopathology, 13 (72%) had unifocal nodules, 14 (78%) were completely encapsulated, and 6 (33%) had vascular invasion. Two tumors met criteria for non-invasive follicular thyroid neoplasm with papillary-like nuclear features. No lymph node metastases were found in any of the 13 (72%) patients who underwent lymph node dissection. Only 1 (6%) patient, who was found to have multifocal microPTC on pathology and persistent cervical lymph node disease on radioiodine whole body scan, had distant metastases. When strictly defined, fvPTC is associated with a low risk of invasion and bilateral disease. Future studies are needed to assess whether lobectomy with surveillance is sufficient in pediatric patients with low-risk features: no prior radiation or genetic risk; unilateral disease with no signs of extra-thyroidal extension or lymph node metastases on pre-operative ultrasound; unifocal tumor with complete encapsulation, no/minimal lymph node metastases, and no vascular invasion.
Thyroid Hormone Metabolism & Regulation Thursday Poster Clinical
THE ASSOCIATIONS OF URINARY COTININE-VERIFIED ACTIVE, AND PASSIVE SMOKING WITH THYROID FUNCTION: ANALYSIS OF POPULATION-BASED NATIONWIDE DATA
The effect of active and passive smoking on thyroid function has not been established and inaccurate smoking status based solely on self-report could contribute to these inconsistent results. The present study aimed to evaluate the association between biochemically verified active and passive smoking and thyroid function in a nationwide Korean population. 3412 subjects with no thyroid disease (hyperthyroidism, hypothyroidism, goiter, or Hashimoto's thyroiditis) and who were not taking thyroid medication were included in this population-based cross-sectional study. Smoking status was identified on the basis of self-report and urinary cotinine levels. Kruskal-Wallis and Jonckheere-Terpstra trend tests were performed to evaluate the association between smoking exposure and thyroid function. Multivariate logistic regression analysis was used to estimate the effect of smoking on subclinical hypothyroidism. Biochemically verified active and passive smoking rates were 43.4%, and 23.3% in men and 10.0%, and 23.0% in women, respectively. Active smokers showed significantly lower iodine states relative to passive and nonsmokers. Active smoking was associated with decreased serum TSH levels in both sexes, but a dose-response relationship between smoking exposure and decreasing TSH levels was only observed in men. Passive smoking slightly decreased TSH levels, but the decrease was not statistically significant. subclinical hypothyroidism(SCH) prevalence was 5.1% (4.2% in men, 6.1% in women) and the risk of SCH decreased as smoking exposure increased in a multivariate adjusted analysis (P trend = 0.013 in men, 0.039 in women). Active and passive smoking was associated with decreasing serum TSH and negatively associated with SCH in a Korean population. This association could be attributed to relatively low iodine states observed in active smokers.
Thyroid Nodules & Goiter Thursday Poster Clinical
IMPLEMENTATION OF A MULTIDISCIPLINARY THYROID BIOPSY CLINIC (MTBC) REDUCES THE RATE OF NON-DIAGNOSTIC CYTOLOGY AND THE NUMBER OF SURGICAL REFERRALS
This study was conducted to evaluate the impact of the implementation of a Multidisciplinary Thyroid Biopsy Clinic (MTBC) on the average nodule size biopsied, the number of patients that underwent thyroidectomy due to non-diagnostic cytology and the percentage of non-diagnostic cytology (NDC) performed by fellows in training. We performed a retrospective chart review of consecutive nodules biopsied before vs after the implementation of MTBC on April 30, 2009. Information collected included age, gender, nodule size, needle passes and slides per nodule and Bethesda category. Assuming a standard deviation of 10 mm, a sample size of 150 nodules per period would detect a 5-mm difference in mean nodule size with at least 80% power. Percentages and means were compared with a chi-square test and independent samples t-test respectively. A generalized linear model that assumed a Poisson distribution was used to compare slide counts between periods. After excluding anechoic cysts, 210 nodules biopsied before MTBC and 232 nodules biopsied after MTBC were included in the analysis. After the MTBC, smaller nodules were biopsied (mean size 23.5 mm vs 20.0 mm; p value <0.001); the percentage of nodules with NDC decreased (41.4% vs 10.8%; p value <0.001); fewer patients with NDC underwent thyroidectomy (25.2% vs 16.4%; p value 0.021); fewer slides were procured per nodule (mean 8.4 vs 7.7; p value = 0.004). Only the decrease in the number of air-dried slides was significant (3.7 vs 2.6; p value <0.001). Implementing of a MTBC was found to have a positive impact on the care of patients with thyroid nodules. Development of the MTBC was primarily driven by the desire to better educate both endocrine and cytopathology follows in the technique ultrasound-guided FNA, adequate preparation of FNA samples, and management of thyroid nodules. The quality of thyroid FNA performed by fellows improved significantly with fewer non-diagnostic cytology while fewer slides were obtained per patient. The reduction in NDC reduces cost associated with repeat FNA and avoids unnecessary surgical referrals and subsequent thyroid surgeries.
Thyroid Nodules & Goiter Thursday Poster Clinical
OUTCOMES OF THYROID NODULES WITH BETHESDA III AND IV CYTOLOGY: AN INSTITUTIONAL EXPERIENCE OVER 5 YEARS
The 2009 Bethesda System for Reporting Thyroid Cytology aimed to provide a uniform standard for interpreting thyroid fine needle aspiration (FNA) specimens. Estimated malignancy rates of AUS/FLUS Bethesda III (B3) is 5-15% and 15-30% for FN/SFN Bethesda IV (B4). Actual malignancy rates of these indeterminate categories, however, vary significantly among institutions. Our objective was to review the prevalence, clinical course and outcomes of FNA specimens in B3 and B4 over a 5-year period at our institution. A retrospective analysis of 2019 FNAs was performed at the University of Colorado from 2011–2015. Molecular, surgical, and clinical follow-up were included to evaluate outcomes and risk of malignancy in Bethesda 3 and 4. Of over 2000 FNA samples analyzed, 231 (11.4%) were B3 and 80 (4%) were B4. Surgery was pursued in 92 (40%) B3 cases: 23 of which confirmed malignancy in the biopsied nodule (25.0% average malignancy rate for this surgical group, range 8-41% by year). In the B4 group, 55 subjects (69%) underwent surgery with 14 malignancies (25.5% rate of malignancy for this surgical group, range 0-42% by year). Molecular testing was performed in 54% of B3 cases with nearly half (49%) having a benign Afirma GEC. Of the 53% B4 cases that underwent molecular testing, 29% had a benign GEC. In the B3 or B4 cases with a benign GEC result and at least 3 months documented follow-up, the median length of follow-up was 41 months (B3) and 52 months (B4). Only 8.2% (5/61) of subjects with benign GEC underwent surgery, none demonstrating malignancy in the targeted nodule. Nodule size remained stable in most GEC benign cases followed clinically (79% of B3 and 71% of B4) without any malignant cytology on repeat FNA. Our 5-year review demonstrates that malignancy rates of B3 and B4 at our institution are consistent with estimated Bethesda rates. There was, however, high variability from year to year. We propose that an average of at least 3 years should be used for reporting institutional malignancy rates to aid in clinical decisions. Finally, our longer-term follow-up of B3 and B4 cytology with benign Afirma GEC confirms that these nodules are likely benign.
Friday, October 20, 2017
Autoimmunity Friday Poster Basic
ANTIGENICITY OF A MAJOR TSH RECEPTOR SPLICE-VARIANT
Bioinformatic analysis predicts the existence of human TSHR isoforms and we have previously described the cloning of a 1.3 kb TSH receptor variant (v1.3). Studies have associated SNPs in the TSHR gene region with Graves' disease suggesting that such variants may have an important role in disease etiology. Hence, mRNA splicing may lead to coexpression of multiple TSHR proteins which may influence the autoimmune response against the TSHR.
In this study we expressed TSHR v1.3 in heterologous cells and have started to examine its physiological and pathophysiological significance. The TSHR v1.3 gene is encoded by the first 8 exons of the TSHR including the signal peptide followed by a unique C terminus intronic region of 63 base pair (21aa). We cloned this entire ORF into a mammalian expression vector (PSec Tag2) designed for secretion due to the presence of a leader sequence (Igkappa leader) in its N terminus and a 6X histidine fusion tag at the C terminus. Stable clones of TSHR v1.3 were generated in HEK 293 cells and protein purified by Ni affinity column. The binding of the purified protein to TSHR receptor stimulating antibody and TSH was examined by immunoprecipitation. Tissue profiling of the variant was carried out by RT-PCR on different human tissue cDNA using specific v1.3 primers. The variant protein, though expressed within the cells, was not secreted. This indicated the importance of the transmembrane domain and carboxyl tail in the proper trafficking of such TSH receptor isoforms. Initial RT-PCR analyses of cDNA prepared from a large variety of different human tissues including thyroid, bone and fat indicated the wide expression of this TSHR variant wherever the full length TSHR was also expressed. Immunoprecipitation demonstrated that both TSH receptor stimulating antibody MS1 (with a conformational epitope) and human recombinant TSH were able to bind TSHR v1.3 protein. A TSH receptor isoform that is expressed by alternative splicing in the thyroid and many other extra thyroidal tissues is a competitor for TSHR antibody and TSH binding and may modulate their actions and serve as an antigen source in autoimmune thyroid disease.
Disorders of Thyroid Function Friday Poster Clinical
EMPATHY: A NEW TOOL FOR IDENTIFYING THE MOST SUITABLE THYROXIN FORMULATION IN HYPOTHYROID PATIENTS
Hypothyroidism therapy is based on the administration of appropriate dose of L-thyroxine (L-T4). Absorption of L-T4 takes place in the duodenum and upper tract of the small intestine (jejunum), is maximal when stomach is empty, and is affected by a number of gastrointestinal disorders, including Helicobacter pylori–related gastritis, as well as ingestion of drugs, dietary fibers, and herbal remedies.
Failure to achieve a good control of disease may be due to malabsorption in 40% of cases, or to poor compliance to L-T4 therapy in 60% of cases.
During the past few years, various L-T4 formulations (in tablets, soft-gel capsules and liquid solution) have become available for clinical use. Liquid or gel formulations may be considered in subjects with hampered L-T4 absorption or who are not adherent to breakfast waiting time after L-T4 administration.
Questionnaires to assess adherence to therapies are available and also adapted to patients with hypothyroidism. On the contrary, there are no tools available to detect malabsorption disorders and then addressing the endocrinologist in choosing the most appropriate therapy.
Here we present EMPATHY (Evaluation of Malabsorption in PATients with HYpothyroidism): a questionnaire consisting of 13 questions which may help the endocrinologist to identify malabsorption disorders and then choose the most appropriate L-T4 formulation for each patient. EMPATHY allows to evaluate not only lactose and gluten intolerances but also some other allergies (nickel, histamine, citric acid, cornstarch) and alcohol intolerance.
We administered EMPATHY to 150 newly diagnosed hypothyroid patients (50 males and 100 females). Exclusion criteria were previous thyroidectomy for thyroid cancer, central hypothyroidism, diabetes, obesity, current L-T4 therapy and pregnancy. EMPATHY resulted extremely useful in the clinical practice allowing a better personalization of L-T4 replacement therapy and then a more rapid achievement of good control of the disease with smaller need of subsequent dose adjustments.
Thyroid Cancer Friday Poster Basic
MICRORNA-146B-3P PROMOTES CELL METASTASIS BY DIRECTLY TARGETING NF2 IN HUMAN PAPILLARY THYROID CANCER
MiR-146b has been reported to be over-expressed in papillary thyroid cancer (PTC) and showed a strong association with aggressive PTC.MiR-146b-5p has been confirmed to increase cell proliferation by repressing SMAD4, however as the other mature expression of miR-146b, detailed functional analysis of miR-146b-3p has not been carried out. In this study, we aimed to identify miR-146b-5p and -3p differentially expressed in PTC with more aggression, such as lymph node metastasis and further elucidate the contribution and mechanism of miR-146b in the process of PTC metastasis. Expression of miR-146b-5p and miR-146b-3p were assessed in primary tumors and metastasis samples of PTC patients. BHP10-3 cells were cultured and the abilities of migration and invasion were detected by RTCA assay and transwell assay after over-expressed miR-146b-5p or miR-146b-3p with microRNA mimics. PTC xenograft models were used to examine the effect of miR-146b-3p on PTC metastasis ability in vivo. Direct downstream target of miR-146b-3p was analyzed by luciferase reporter assay and western blot. MiR-146b-5p and miR-146b-3p expression was significantly higher in thyroid cancer tissues and cell lines compared to normal thyroid tissue and cells. Moreover, expression of miR-146b-5p and miR-146b-3p was further higher in thyroid metastatic nodes than thyroid cancer. After overexpression of miR-146b-5p or miR-146b-3p in BHP10-3, papillary thyroid cancer migration and invasion were increased. Notably, miR-146b-3p increased cell migration and invasion more obviously than miR-146b-5p. Overexpression of miR-146b-3p also significantly promoted PTC tumor metastasis in vivo. Luciferase reporter assay revealed that NF2 was a downstream target of miR-146b-3p in PTC cells as miR-146b-3p bound directly to the 3′ untranslated region of NF2, thus reducing protein levels of NF2. Over-expression of merlin (the protein product of NF2 gene) reversed the enhanced aggressive effects of miR-146b-3p. In conclusion, this is the first report documenting that over-expression of miR-146b is associated with PTC metastasis and miR-146b-3p plays an important role through suppressing NF2 gene. These findings suggest a diagnosis and therapeutic benefit in PTC metastasis.
Thyroid Cancer Friday Poster Translational
MICROBIAL MIMETICS FOR IMMUNOTHERAPY OF MTC: EPITOPE VALIDATION AND IN VIVO EFFICACY IN A SYNGENEIC TUMOR MODEL DERIVED FROM THE P25OE CELL LINE
Metastatic medullary thyroid carcinoma (MTC) is a rare and incurable calcitonin-secreting neoplasm. While the TKIs cabozantinib and vandetanib have improved outcomes in advanced MTC, there is no curative adjuvant therapy for patients with surgically unresectable disease. Therefore, novel therapeutic approaches are warranted. Recently, the combination of immune checkpoint inhibitors (ICIs) and cancer vaccines has been evaluated in other tumor types, with a PSA-specific vaccine + ipilimumab demonstrating encouraging survival in prostate cancer. Prior to the availability of ICIs, Schott et al. observed clinical responses and calcitonin-specific immunity in 3/7 MTC patients treated with calcitonin-pulsed dendritic cells.
In light of these prior studies and the cost/complexity of cell-based therapies, we developed an off-the-shelf calcitonin-specific immunotherapy for MTC based on the novel Microbial Mimetics (MM) vaccine platform, and tested its efficacy in the p25OE syngeneic MTC tumor model as monotherapy and combined with ICIs. MM are comprised of tumor-associated antigenic cargo complexed to immune-stimulatory agonists of TLR2/7/8/9, which spontaneously form bacterial-sized particles when mixed in PBS. MM containing human calcitonin and the mouse calcitonin signal peptide were synthesized. For experiments, mice were inoculated with 10 million p25OE cells in the left hind flank. Mice were divided into four groups (n = 5) comprised of control (PBS) (A), MM monotherapy (i.m. injection) (B), ICIs (anti-PD-1/anti-CTLA-4/anti-CD27) (C) and MM+ICIs (D). Treatment was administered every 4th day once tumors reached ∼100 mm3. Relative to (A), growth inhibition was seen in groups (B) and (C) of 61% and 32%, respectively at day #30. For (D), 3/5 mice exhibited full tumor regressions and growth inhibition was observed in 2/5 mice. ELISPOT and ELISA were performed to characterize MM immunogenicity.
Putative MHC Class I calcitonin epitopes were analyzed for both mouse (Kb/Db) and human (HLA-A1/A2/A3/A11/A24) alleles using ImmuniTrack's MHC binding stability assay. High stability epitopes were identified for both mouse and human alleles, justifying the potential for clinical translation.
Thyroid Cancer Friday Poster Translational
DIGITAL IMAGE ANALYSIS OF PROGRAMMED DEATH-LIGAND 1 EXPRESSION PROVIDES A TECHNICAL ADVANCE IN THE DIAGNOSIS OF THE THYROID CANCER AMONG ENCAPSULATED FOLLICULAR LESIONS
Our laboratory previously reported that programmed death-ligand 1 (PD-L1) is a useful protein biomarker for distinguishing encapsulated invasive malignant follicular variants of papillary thyroid carcinoma (EFVPTC) from a very likely benign non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP); however, traditional immunohistochemical biomarker postanalysis has relied on manual scoring that is time consuming and can be subject to individual bias. The aim of this study was to develop a digital image analysis (DIA) algorithm that provides an efficient, reproducible and accurate quantitation of PD-L1 expression. One hundred and fifty-three thyroid nodules consisting of 48 reclassified NIFTP, 44 invasive EFVPTC, 26 benign nodules and 35 encapsulated follicular lesions/neoplasms with coexisting predominant lymphocytic or Hashimoto's thyroiditis (LT) were scored for PD-L1 (E1L3N rabbit anti-human mAb) expression manually and by DIA. The DIA analysis protocol package for cytoplasmic and membrane stain quantitation was developed using the Visiopharm Integrator System. Three fully automatic [Systematic Uniform Random Sampling (SURS), hotspot nucleus, and hotspot nucleus and 3,3’-Diaminobenzidine (DAB)] and one semi-manual tumor sampling methods were also assessed to optimize the DIA protocol package and to determine the receiver operating characteristic (ROC) performance. Statistical analyses were performed using one-way ANOVA test (significance p < 0.05). Using DIA quantitation of PD-L1 expression, a significant difference was observed between invasive EFVPTC and NIFTP (p < 0.001); but none between NIFTP and benign nodules (p = 0.113). DIA outperformed manual scoring in efficiency, reproducibility, area under the curve (AUC), and interobserver variability. Hotspot nucleus was the most clinically relevant tumor sampling method with the greatest AUC of 0.728. A fully automatic protein biomarker DIA algorithm using a histomorphological approach was developed to more objectively and accurately quantitate PD-L1 expression in encapsulated papillary-follicular thyroid neoplasms that can be used as a useful aid to histopathological diagnosis and avoid overdiagnosis and overtreatment of NIFTP.
Thyroid Cancer Friday Poster Clinical
BRAF TESTING IN CONJUNCTION WITH THE ROSETTAGX REVEAL MIRNA CLASSIFIER FROM A SINGLE FNA SMEAR
The BRAF V600E mutation (BRAF) is the most common genetic alteration in papillary thyroid carcinoma and may confer a worse prognosis. We have previously reported the development and validation of RosettaGX RevealTM (Reveal), a microRNA-based test for the classification of cytologically indeterminate thyroid Fine Needle Aspirate (FNA) smears. The aim of this study was to develop a method for the simultaneous use of Reveal and the detection of BRAF mutation status using a single thyroid FNA smear. The study included >90 formalin-fixed paraffin-embedded (FFPE) tissues and FNAs, from which high-quality dual DNA and RNA extraction was performed using proprietary technologies. The BRAF mutation status was detected by proprietary qRT-PCR methods for DNA and RNA fractions. The results were compared with those of the Competitive Allele-Specific TaqMan® PCR (castPCRTM) assay. In addition, samples were hybridized to proprietary small RNA microarrays. We developed a method for detecting the BRAF mutation status and simultaneously performing the Reveal assay, using a single FNA smear. DNA and RNA were extracted from each sample. The quality and quantity of the RNA and DNA was not affected by extracting both fractions in parallel, compared with extracting each independently. The mutation status could be detected using as little as 2.5ng DNA, whereas for castPCR the recommended minimum amount is 20ng. The analytical and clinical sensitivities of the DNA test was 1%. The concordance with castPCR, when testing 5ng DNA in 18 FFPE samples and 53 FNA samples was 98%. When examining the BRAF status of the RNA fraction of the same samples, the concordance with castPCR was 92%. In addition, the expression levels of several microRNAs, including hsa-miR-146b-5p, were found to be associated with BRAF mutation status. We developed a sensitive and reliable method for testing BRAF mutation status in a single thyroid FNA smear that can be simultaneously used for the RevealTM test. The combined testing maximizes the utilization of FNA materials, supports the diagnosis of samples classified as suspicious by Reveal, and may be used for prognostic assessment.
Thyroid Cancer Friday Poster Clinical
EXPLORING OF A NOVEL METHOD OF IDENTIFYING PARATHYROID GLANDS
To investigate the possibility of rapid identification of parathyroid glands by intraoperative bioelectrical impedance spectroscopy (BIS), which identifies the spectral characteristics of the isolated parathyroid glands. A total of 510 sets of bioelectrical impedance spectrum data (including 94 sets of parathyroid, 308 sets of thyroid, 92 sets of lymphoid tissue and 16 sets of adipose tissue) using four electrode measurement was collected from 87 thyroid tumor operations from October 2015 to January 2017 in our department. The characteristic parameters including the characteristic frequency and other BIS were obtained by fitting the Cole-Cole model. One way ANOVA test and statistical differential analysis of the characteristic index were carried out to assess the ability of these parameters to recognize their respective tissues. The intraoperative frozen biopsy was used to confirm parathyroid glands. When using characteristic frequency spectrum (CFS) FC to analyze the ex vivo tissues, the mean value of parathyroid glands, thyroid glands, lymph node in central area and adipose tissue around parathyroid glands were 200.9kHz, 131.3kHz, 377.4kHz and 666.6kHz, respectively. When using CFS R0/R∞ to analyze each tissue, the mean values were 4.37, 5.57, 6.12 and 12.69 respectively. One way ANOVA analyses showed significant differences between the four tissues using either CFS FC or R0/R∞. When comparing the FC and R0/R parameters of the parathyroid tissue with those of thyroid tissue, lymph node, and fat tissue from the ipsilateral side of the same patients, there are also significant differences between groups. These data showed that parathyroid glands had a significant different characteristics than the adjacent tissues revealed by BIS. These results imply that it is possible to differentiate parathyroid tissue with other associated tissues by bioelectrical impedance spectroscopy techniques and appropriate data classification methods. We were able to identify parathyroid glands rapidly by intraoperative BIS, which can shorten the waiting time of parathyroid to be confirmed by intraoperative frozen pathological biopsy, so as to protect the parathyroid and shorten the operation time.
Thyroid Cancer Friday Poster Clinical
QUESTIONING THE QUALITY OF ONLINE THYROID CANCER INFORMATION
Thyroid cancer is amongst the most common malignancies in North American young adults. As such, many thyroid cancer patients likely use the internet to seek information. This project aims to evaluate the quality of online information for thyroid cancer patients. The search term “thyroid cancer” was entered into Google and meta-search engines Yippy and Dogpile. Inclusion and exclusion criteria were used to create a list of the “top 100” websites with thyroid cancer patient information. A previously-validated structured rating tool was used to assess sites' currency, disclosure, attribution and content. Two reviewers independently coded sites, and results were evaluated to ensure maximum inter-rater reliability. A search for “thyroid cancer” returned 4,760,000 hits on Google, 610,759 on Yippy, and an undisclosed number on Dogpile. Only 26% of the top 100 sites named the authors, and 56% cited sources. 18% contained significant bias. While only 41% provided the date of the most recent update, of those, 90% (36 sites) had been updated within two years. Based on the Flesch-Kincaid Grade Level, 98% of websites required at least high school education for comprehension.
With respect to content, a definition was most often present, on 94% of sites, followed by treatment options (93%) and diagnostic work-up (92%). Least commonly covered topics were prevention (37%) and incidence or prevalence (57%). While diagnosis and treatment were among the most frequently present, they were also the most frequently incomplete or inaccurate: only 50% of discussions of diagnosis were complete and accurate, and 47% for treatment. Many websites are available for patients with thyroid cancer, however quality is variable. Most sites lack information patients can use to assess a website's trustworthiness, such as authorship, citations and currency. Nearly all sites require a reading level far above the average of most patients (i.e. grade six). There are significant gaps in accurate information regarding diagnosis and treatment. This information can help guide care providers and thyroid-centric societies in developing patient education resources.
Thyroid Cancer Friday Poster Clinical
CIRCULATING BRAFV600E CELL-FREE DNA (CFDNA) DETECTED BY DROPLET DIGITAL PCR (DDPCR) AS A BIOMARKER FOR MONITORING RESPONSE TO THERAPY IN THE MANAGEMENT OF BRAF MUTATED (BRAFM) ANAPLASTIC THYROID CARCINOMA (ATC) PATIENTS (PTS)
There is currently no biomarker for ATC. We previously showed that ddPCR is a reliable test to identify BRAF mutations in ATC. Our objective was to evaluate the use of BRAFV600E cfDNA as a biomarker in BRAFm ATC pts.BRAFm ATC pts were followed prospectively. Plasma samples were collected at the time of baseline imaging and at scheduled follow up, at no less than biweekly intervals. ddPCR analysis was performed on isolated cfDNA to determine the BRAFV600E allelic fraction. Concordance of levels of cfDNA with changes in tumor burden measured on imaging were calculated while receiving treatment. cfDNA samples drawn in between imaging events (“unpaired cases” of cfDNA with imaging) were analyzed for concordance with subsequent imaging to determine cfDNA's ability to predict response. From 3/2016-7/2017, 16 eligible pts were included. Median age was 68 years; 10/16 (63%) were men. Stage at diagnosis: 10/16 (63%) were stage IVC; 6/16 (37%) stage IVB. Pts received one or more of the following treatments: surgery 2 (12%), chemoradiation 4 (25%), BRAFi 12 (75%), chemotherapy 5 (31%), and BRAFi with immunotherapy in 4 (25%). Restaging images were done at median of 6 weeks (1.6-20.4). Median time interval between successive samples was 3.8 weeks (range 1.3-18). There were a total of 46 cfDNA samples paired with imaging: 26 with regression, 17 with progressive disease (PD) and 3 with no change in tumor size (stable disease) on imaging. Concordance in cfDNA levels: 94% with regression, 100% with stable disease and 47% with PD. 11 pts had samples drawn at a median of 3.7 weeks in between staging resulting in 17 unpaired cases. 12 samples (71%) were predictive of response to treatment. The earliest cfDNA response was at 1 day after surgery and 2 weeks after starting BRAFi.BRAFV600E cfDNA by ddPCR may be a reliable biomarker as a predictor of response to therapy in BRAFm ATC. Although not reliably concordant with progression, possibly due to acquisition of new mutations in the tumor, this could be used as an early marker of positive response, similar to thyroglobulin use in differentiated thyroid cancer. Larger studies are needed.
Thyroid Cancer Friday Poster Clinical
REGIONAL VARIATION IN INITIAL SURGICAL TREATMENT OF WELL-DIFFERENTIATED THYROID CANCER: IS THERE AN IMPACT ON RECURRENCE?
It is not clear to what extent variation in initial surgical management of well differentiated thyroid cancer (WDTC) affects outcomes. The objective of the present multi-center study was to determine if variations in the initial surgical management of WDTC impact subsequent disease recurrence. CANNECT is a multi-center, longitudinal study of thyroid cancer diagnosed and treated between 2000–2010 in six centers across Canada: Ontario (London, Toronto, Hamilton), Manitoba (Winnipeg), Nova Scotia (Halifax), New Brunswick (Fredericton). The current report examined disease recurrence after initial surgical management for WDTC among patients over 18 years in age. The study population included 2762 patients, 79% females with mean age at diagnosis 48 + 14 years. Papillary carcinoma accounted for 94% of the cases and this proportion was stable over the 10 years (p = 0.20). Stage I WDTC was observed in 67% of the patients, Stage II 13%, Stage III 14% and Stage IV in 6%. Less than total thyroidectomy (hemi- or subtotal) was performed in 16% (between-centre range 2% to 33%), and the remainder had total thyroidectomy (one- or two-stage). Central compartment (Level VI) lymph node dissection was performed in 29% (between-centre range 11% to 96%), level VII dissection in 1% (range 0% to 22%), and lateral neck dissection in 9% (range 1% to 25%). There was a significant increase over time in the proportions undergoing total thyroidectomy (p < 0.001) and central compartment lymph node dissection (p < 0.001). Patients were followed for a median duration of 7.3 years (range 0.1-17.3 years) during which 99 (3.6%) developed a recurrence (rate 4.7 per 1000 person-years). There was no significant difference in the proportion with recurrence of WDTC between participating centers (p = 0.20). In spite of significant differences in the initial surgical management of WDTC amongst the six participating study centers, this did not significantly affect thyroid cancer recurrence.
Thyroid Cancer Friday Poster Clinical
THE INCIDENCE AND RISK FACTORS OF PARATHYROID AUTOGRAFT IN THYROID CANCER SURGERY, DOES GRAFT NUMBER AFFECT OUTCOME?
Hypoparathyroidism is a major complication in thyroid cancer surgery, parathyroid autograft is an important procedure to avoid it. We want to find the risk factors of parathyroid autograft and whether the graft number affect outcome. From December 2005 to August 2015, 1173 thyroid papillary cancer patients operated by a single unit in our hospital were included in this retrospective cohort study. Based on whether received parathyroid autograft, the patients were categorized into two groups: parathyroid autograft group and non-parathyroid autograft group. Patients' demographical and tumor characteristics, surgical procedure, the number of parathyroid autograft, the parathyroid function were analyzed. Among the 1173 patients, there were 507 in parathyroid autograft group and 666 in non-parathyroid autograft group. The median (range) follow-up was 39 (15–132) months.
Age <45(43.18% vs 43.27%, p = 0.024), multicentric (53.23% vs 39.39%, p = 0.000), surgical procedure (total thyroidectomy alone vs with unilateral CND extension vs bilateral CND extension respectively 52.98% vs 44.44% vs 30.39, p = 0.000), first operation (43.76% vs 21.42%, p = 0.020) had a high risk of parathyroid autograft.
The results of the sex, tumor size above 2cm, extrathyroid lension, lateral lymph node dissection extension, metastatic ln were not significantly different between the groups. (p > 0.05)
With graft number increase, serum calcium (mmol/l) level significantly decreased, which was 2.28, 2.26, 2.27, 2.17, 2.19 for 0, 1, 2, 3, 4 gland transplants respectively, p = 0.000. There were no significant difference in parathyroid hormone level, the incidence of low parathyroid hormone (<13 pg/ml), the incidence of low calcium (<2 mmol/l), and the incidence of permanent hypoparathyroid. (p > 0.05) Age <45, multicentric, surgical procedure, first operation were the main related risk factors of parathyroid autograft. The long-term outcome is not affected by the increased number of parathyroid autograft except a decreasing serum calcium level.
Thyroid Cancer Friday Poster Clinical
BONE METASTASIS OF DIFFERENTIATED THYROID CANCER: CRITICAL ROLE OF IODINE 131
Bone metastases represent a frequent complication especially of follicular thyroid cancer and severely reduce the quality of life causing pain, fractures. For well-differentiated lesions in asymptomatic patients, whole body post therapeutic scans with Iodine 131 is the most efficient diagnostic modality.131I is the first line of treatment. This is a retrospective study including 92 patients with bone metastasis of differentiated thyroid cancer (DTC) with regular follow up. Those 69 women and 23 men with DTC have had an average age of 52 years (range from 20yrs to 70yrs) and presented bone metastasis with the following pathological variants: 38 follicular (pure or variant forms), 18 papillary (pure), 29 variant forms of papillary and 7 indeterminate. In 41 patients, bone metastasis were the onset of DTC (inaugural) and in 51 patients bone metastasis were discovered during the first whole body post therapy (WBPT) with I131 (44) or the second WBPT (7 patients). In 32 patients bone metastases were alone. The most common site of bone metastases were spine (56) followed by pelvis (40) then skull (30). 92 patients received at least 11GBq with a global average of 18GBq. For those patients who were treated by radio iodine alone the average of cumulative dose was little bit inferior than those patients who received an additional therapy for their bone metastases (16GBq versus 20GBq). During the follow up any complication of radio iodine treatment was noted for the 92 patients. Intrinsic stimulation alone was used in 57 patients and associated with recombinant TSH in 35 patients. 59 patients of 92 are well stabilized during 3 years by radio iodine alone or associated with another therapeutic modality. 72 patients have a survival of more than 5 years among them 28 patients with more than 10 years survival. Radio iodine treatment of bone metastasis under intrinsic alone or associated with external stimulation is an appropriate, efficient and safe therapy for bone metastasis of differentiated thyroid cancer. However active surveillance for at least twice a year is recommended for assessing regularly the status of bone metastases and decide whether another complementary therapy is needed or not.
Thyroid Cancer Friday Poster Clinical
ANALYTICAL PERFORMANCE OF THE THYROSEQ® VERSION 3 GENOMIC CLASSIFIER FOR CANCER DIAGNOSIS IN THYROID NODULES
Molecular testing of thyroid nodules with indeterminate FNA cytology has growing clinical utility. All currently available molecular tests have limited use in oncocytic nodules. The goal of this study was to expand the current ThyroSeq v2 assay by adding additional diagnostic markers and evaluate analytical performance of the test classifier in thyroid nodules and cancer. ThyroSeq v3 is a DNA and RNA based next-generation sequencing assay that analyzes 112 genes for point mutations, fusions, copy number changes, and expression levels. A Genomic Classifier (GC) was developed based on the weighted score for each genetic alteration to achieve the highest accuracy in separating benign and malignant thyroid nodules. The classifier was developed using a training set of 238 surgically removed thyroid samples which consisted of all main types of thyroid cancer, benign lesions, and selected non-thyroidal lesions. It included 29 oncocytic FTC, 13 oncocytic FV of PTC, 15 oncocytic FA, and 11 oncocytic HN. The performance of GC was then evaluated in an independent set of 175 FNA samples with known surgical follow-up. In the tissue training set, ThyroSeq v3 GC demonstrated a sensitivity of 93.9%, specificity of 89.4%, and accuracy of 92.1%. Specifically, the test correctly classified 52 out of 57 PTC and 10 out of 11 conventional FTC. Among oncocytic lesions, 39 out of 42 cancers and all 11 oncocytic HN were correctly classified, whereas 8 out of 15 OA were also classified as positive. Overall, the GC showed a sensitivity of 92.9% and specificity of 69.3% in oncocytic lesions. All 14 medullary cancers and 13 parathyroid nodules were correctly classified. In the FNA validation set, ThyroSeq v3 GC showed a sensitivity of 98.0%, specificity of 81.8%, and accuracy of 90.9%. The test receiver-operated-characteristic (ROC) curve showed an area under the curve of 0.93 (95%CI: 0.90-0.97) in tissue training set and 0.91 (95%CI: 0.86-0.96) in FNA set. An expanded ThyroSeq v3 GC has high sensitivity and specificity of cancer detection, including oncocytic follicular and papillary carcinomas, medullary carcinomas, and parathyroid lesions. Clinical validation of the ThyroSeq v3 GC is being assessed in a prospective multi-center study.
Thyroid Hormone Action Friday Poster Basic
LONG-TERM DOSING WITH THE THYROID HORMONE RECEPTOR AGONIST VK0214 REDUCES VLCFA LEVELS IN PLASMA AND TISSUE IN AN IN VIVO MODEL OF X-LINKED ADRENOLEUKODYSTROPHY
X-linked adrenoleukodystrophy (X-ALD) is a debilitating neurodegenerative disorder that results from mutations in the ABCD1 gene. ABCD1 encodes a peroxisomal membrane transporter protein involved in the degradation of very long chain fatty acids (VLCFAs). ABCD1 mutations lead to the accumulation of VLCFAs in plasma and tissues. Elevated VLCFA levels contribute to the CNS demyelination, peripheral neuropathy, and adrenal insufficiency observed in patients with this disease. Thus, decreasing VLCFA levels is considered a primary goal of therapy. Increased expression of the thyroid hormone beta receptor (TRβ) dependent compensatory transporter ABCD2 has previously been shown to reduce plasma VLCFAs in an animal model of X-ALD. A reduction in tissue VLCFAs may further enhance the benefits of plasma VLCFA reductions by lowering the direct exposure of these key drivers of disease progression.
The objectives of this study were to determine the effect of long-term dosing (25 wks) of VK0214, the prodrug of potent TRβ agonist VK0214A, on plasma and tissue VLCFAs in a rodent model of X-ALD. We previously reported encouraging results from a 6 wk study in this model. In the current study, the duration of treatment, and cohort sizes were increased, and tissue VLCFA effects were evaluated. A previously-described ABCD1 knockout mouse model was utilized. Cohorts of 12 male hemizygotes received daily chow adsorbed with 10 mg/kg VK0214, or unadulterated chow, for 14 wks, at which point the mice received chow adsorbed with 30 mg/kg VK0214 for an additional 11 wks. Blood was evaluated at wks 0, 6, 9, 12, 20 and 25. Tissues were collected at wk 25. VLCFAs were analyzed by LC-MS/MS for plasma lysophosphatidyl choline and tissues were evaluated for VLCFAs and ABCD2 expression. Oral dosing of the TRβ agonist prodrug VK0214 for 25 wks led to significant reductions in VLCFAs in both plasma and tissues, with concomitant increases in ABCD2 transporter expression. These results suggest the potential importance of pharmacologic modulation of the TRβ receptor as an approach to the treatment of X-ALD. Further work, including ex vivo examination of the effects on inflammatory markers of X-ALD and a clinical study in patients, is planned.
Thyroid Hormone Metabolism & Regulation Friday Poster Clinical
CIRCANNUAL VARIABILITY OF THYROID AXIS FUNCTION BASED UPON TSH RESULTS FROM HYPOTHYROID-TREATED AND HEALTHY INDIVIDUALS OVER TIME
The effect of season on thyroid function was examined in a large out-patient cohort, using TSH results from hypothyroid patients on replacement therapy as compared to healthy individuals. 247,302 TSH results from 40,415 subjects with at least one hypothyroid-related diagnosis and one filled prescription for thyroid medication between 2010 and 2012 were compared with 2,214,891 results from 889,102 healthy individuals. All tests were performed at the Maccabi Healthcare Services' central laboratory between January 2013 and March 2017. Descriptive statistics are expressed as means and standard deviations (SD) for continuous variables and numbers and percentages for categorical variables. The 95% Confidence Interval (CI) for proportions was provided for the percent of tests per month above and below the reference range. The two-sample t-test for independent samples was applied for testing the difference in the TSH values between study and control groups. All analyses were conducted using SPSS V22, Inc., Chicago, IL. The overall mean (± SD) TSH value was higher in the study than in the control group (4.0 ± 7.3 vs 2.3 ± 2.3 mIU/L p < 0.001). Within the study group the percent of tests per month above and below the reference range (%ARR and %BRR) ranged from 33.1–16.6% and 16.9–9.1% respectively for women and 43.2–23.1% and 14.9–6.6% respectively for men.
In the study group mean monthly TSH results were significantly higher in winter (November – February) than in summer (June – September; 4.2 ± 7.4 vs 3.8 ± 7.1 mIU/L p < 0.001). In addition a circannual difference was observed in the %ARR and %BRR. The %ARR was larger and %BRR smaller in winter than in summer (23.8% vs 20.1% p < 0.001 and 11.0% vs 14.1% p < 0.001 respectively). This pattern was observed among women (%ARR 22.6% vs 18.9% p < 0.001 and %BRR 11.2% vs 14.6% p < 0.001 in winter vs summer). In men above age 65 %ARR was significantly larger in winter vs summer (32.7% vs. 26.8% p < 0.001) No variation was observed in the control group. A large percentage of hypothyroid patients are sub-optimally treated. Mean TSH values of women and elderly men on thyroid replacement therapy are higher in winter than in summer. Thyroid hormone demand is increased in winter compared to summer.
Thyroid Imaging Friday Poster Clinical
DIAGNOSTIC VALUE OF ULTRASOUND ELASTOGRAPHY AND COLOR DOPPLER IN THE DETECTION OF MALIGNANT TUMORS OF THE THYROID GLAND
The aim of the investigation: to study the role of elastography and color Doppler in the differential diagnosis of thyroid nodules; and to assess the sensitivity and specificity of the methods implied. The study involved 168 patients with thyroid nodules: among them there were 23 (14%) male and 143 (86%) female patients; mean age being 47.1 ± 1.11 years. All the patients underwent standard diagnostic procedures: an ultrasound investigation, ultrasound elastography, color Doppler and fine-needle aspiration biopsy of nodules followed by cytological analysis. Patients were consisting of three groups: I group – benign (I and II categories according to Bethesda classification, n = 126); II group – suspicious (Bethesda III and IV, n = 29); and III group – malign (Bethesda V and VI, n = 23). Based on the elastography data, no differences were found between groups I and II (p > 0.05). In the third group, there were statistically significant differences (p < 0.001) compared with other groups in both parameters (elasticity score and strain ratio). The sensitivity of the method was 82.6%, while specificity was 67.2%. The prognosis of the positive result (PPV) was 33.3%, while the prognostic value of the negative result (NPV-) was 95.1% (OR = 9.75). From Color Doppler perspective, hypervascularity sign of imaging was OR = 13.1, while central flow sign was OR = 3.5. For achievement of considerably better qualitative and semi-quantitative elastography scores, if considered together, elastography and color Doppler, could produce notably improved diagnostic values on differential diagnosis of malignant thyroid nodules, which contribute to the establishment of an accurate diagnosis in the pre-operative period, which in turn plays an indisputable role in choosing the right tactics for conducting such patients.
Thyroid Imaging Friday Poster Clinical
SPECT WITH REGION GROWING BASED SEGMENTATION ALGORITHM TECHNIQUES PERFORMS BETTER THAN PLANAR IMAGING IN WEIGHT EVALUATION OF THYROID MODEL
Weight evaluation of thyroid or remnant thyroid is critical in the precise 131I therapy for thyroid disease. While, traditional planar imaging can't accurately evaluate thyroid weight. Region growing based segmentation (RGBS) is a new algorithm in SPECT processing techniques. In the present study, we assessed the accuracy of region growing based segmentation algorithm in evaluating the weight of thyroid model. Different models of thyroid were made by a thyroid model filled up with different volume of 99mTcO4- (37MBq), including 5g, 10g, 15g, 20g, 25g, 35g. Thyroid weight was evaluated by region growing based segmentation and traditional planar imaging, respectively. Each measurement was repeated once to ensure the accuracy. Weight of thyroid model evaluated by both RGBS and planar imaging were compared with actual models weight. There was no significant difference between actual weight of experimental thyroid models and that evaluated by RGBS and planar imaging (all P > 0.05). While, the r-value in correlation analysis of RGBS and planar imaging was 0.957 and 0.936 (all P < 0.05), which represented the weight evaluated by RGBS was more relevant to the actual weight of experimental thyroid. Thyroid weight could be more accurately evaluated by region growing based segmentation algorithm SPECT than planar imaging.
Thyroid Nodules & Goiter Friday Poster Clinical
ANALYTICAL PERFORMANCE OF AFIRMA GSC: A GENOMIC SEQUENCING CLASSIFIER FOR CYTOLOGY-INDETERMINATE THYROID NODULE FNA SPECIMENS
Our objective was to verify the analytical performance of the Afirma Genomic Sequencing Classifier (GSC) in the classification of cytologically indeterminate thyroid nodule fine-needle aspirate biopsies (FNAs). The GSC uses an RNA Next Generation Sequencing (NGS) assay to interrogate genomic features in total RNA samples from FNAs, such as gene expression, single nucleotide variants, loss of heterozygosity and fusions. Analytical verification studies were designed to characterize assay performance and robustness, including analytical sensitivity as applied to input RNA mass and limit of detection, analytical specificity from potential interfering substances such as blood and genomic DNA, and within run, between run, and between laboratory reproducibility. Analytical sensitivity studies demonstrated tolerance to variation in RNA input (5-25 ng) and to the dilution of malignant FNA material down to 5%. Analytical specificity studies using malignant samples mixed with blood (up to 95%) and genomic DNA (up to 30%) demonstrated negligible assay interference with respect to false calls. The test is reproducible from RNA isolation through GSC result, including variation across operators, runs, reagent lots, and laboratories, with a total variation of SD = 0.27 for classifier scores on a >8 unit scale (3.4% of the score range), which is well within pre-determined acceptable levels (SD <0.44; 5.5% of score range). The analytical robustness of the Afirma GSC test was successfully verified and strongly supports the routine clinical use of the test in informing patient care.
Saturday, October 21, 2017
Disorders of Thyroid Function Saturday Poster Translational
THE POLYMORPHIC INHERITANCE OF DIO2 RS225014 MAY PREDICT BODY WEIGHT VARIATION AFTER GD TREATMENT
Graves' disease (GD) is an autoimmune disorder characterized by goiter and hyperthyroidism of high triiodothyronine to thyroxine ratio. During active disease, the adaptive response to the increase in basal metabolic rate is weight loss, with weight gain being the rule as thyroid function reestablishes. However, there is great variability in the magnitude of this gain. Predictive factors that might help identify patients who could benefit of some more rigid weight control measures are still lacking. Deiodinase type 2 (D2) is an enzyme that contributes primarily to the intracellular signaling of the thyroid hormone and, consequently, to T3-mediated genomic actions. Cyclic AMP and T3 are transcriptional regulators of the DIO2 gene. The mRNA of DIO2 gene is overexpressed in the thyroid affected by GD and expressed in the human adipocyte, white and brown adipose tissue, hypothalamus, pituitary and skeletal muscle, which are tissues involved in the regulation of body weight and, also, in the pathogenesis of Graves' orbitopathy. The polymorphisms of the DIO2 gene 225014 and rs12885300 can functionally modify this enzyme. To investigate their role in GD, 280 patients (47 men and 233 women-40 ± 12 years old) by the time of diagnosis and 297 controls (53 men and 244 women-40,15 ± 11,21 years old) were genotyped by the Taqman SNP Genotyping technique. Follow-up 24 months after treatment was available in 141 patients. There was no relationship of the investigated polymorphisms with the susceptibility to GD, GO activity at diagnosis or any clinical or laboratory characteristic of the patients. However, the polymorphic inheritance (CC plus CT genotype) of DIO2 rs225014 was associated with a lower body weight variation after GD treatment, when compared to wild type TT genotype (p = 0,0138 adjusted for the follow-up time) and with the positivity of the anti-thyroglobulin antibody, p = 0.0209. We suggest that the polymorphic inheritance of DIO2 rs225014 may help identify predict post-treatment weight behavior in GD patients.
Disorders of Thyroid Function Saturday Poster Clinical
THYROID DYSFUNCTIONS AND AUTOIMMUNITY IN BREAST CANCER PATIENTS: A PROSPECTIVE CASE CONTROL STUDY
There are conflicting reports about relationship of thyroid dysfunctions and autoimmunity in breast cancer (BC) patients. The primary aim of this study is to estimate the prevalence of thyroid dysfunctions and autoimmunity in BC patients and the secondary aims were to investigate outcome of thyroid functions after BC therapy and effect of dysfunctions on clinico-pathologic profile of BC. Prospective case control study (March 2015–March 2017). Women with newly diagnosed BC (n = 191), age matched healthy controls (n = 150) and cancer cervix patient (n = 87) were enrolled. Basal serum free thyroxin (fT4), thyrotropin (TSH) and anti- thyroid peroxidase (TPO) antibody levels were estimated in all the groups (IMMULITE® kits). Repeat estimations were performed twice in BC patients, 3–4 weeks after completing chemotherapy and in follow-up one year after diagnosis of BC. Prevalence of overall hypothyroidism (25.7 Vs 28.0 Vs 24.1%, p = 0.623) and autoimmunity (15.7 Vs 23 Vs 18.4%, p = 0.201) didn't differ significantly among three groups but the prevalence of clinical and self-reported hypothyroidism was significantly high in breast cancer patients (10.8 Vs 0.9 Vs 3.4% p = 0.002). Mean fT4 showed decreasing trend from basal to post chemotherapy and follow-up period (16.1 Vs 15.9 Vs 15.1 pmol/L), whereas TSH was low after chemotherapy but was higher in follow up (2.72 Vs 2.08 Vs 3.08 μIU/mL). Both fT4 (p = 0.686) and TSH values (p = <.001) were lower than basal after chemotherapy. Follow-up fT4 values were less (p = 0.015) and TSH higher (0.388) than basal values. 9.9 % of BC patients who were euthyroid at enrolment become hypothyroid in follow-up. Hypothyroid (5.2 Vs 4.5 cm, p = 0.02) and TPO positive (5.2 Vs 4.1 cm, p = 0.004) patient had significantly small tumors but age of presentation, menopausal status, tumor stage, other tumor characteristics (lymphovascular invasion, perineural invasion, hormone and HER-2/ Neu receptors status) and response to chemotherapy were not significantly different in patients with dysfunctions and autoimmunity in comparison to rest of the patients. Increased incidence of hypothyroidism in BC seems to be a sequel to cancer therapy and not a risk factor.
Thyroid Cancer Saturday Poster Basic
STUDY ON THE ROLE OF CSN6 IN THYROID PAPILLARY CARCINOMA CELLS
The incidence of thyroid cancer has increased worldwide at a rate higher than that of any other cancer. CSN6 is overexpressed in many types of cancers, and such expression is linked to oncogenic activity. However, the detailed biological functions of CSN6 in papillary thyroid cancer (PTC) have not been well characterized. We investigated CSN6 expression in PTC specimens and cell lines. We used short-hairpin RNA-mediated gene silencing to explore the biological effects of CSN6 depletion in PTC cells. The combined effects of CSN6 silencing and FH535 therapy were assessed in terms of cell viability. The mechanism by which CSN6 regulated β-catenin expression was also analyzed.
CSN6 levels were determined by real-time polymerase chain reaction (PCR) (mRNA), Western blotting, and immunochemistry (protein). The CCK-8 and migration assays and orthotopic xenograft transplantation were used to investigate the biological effects of CSN6. We assessed the combined effects of CSN6 silencing and FH535 on cell viability in vitro. We also analyzed the relationship between the CSN6 level and clinical pathological status. CSN6 was overexpressed in human PTCs, and loss of CSN6 attenuated tumor proliferation and migration both in vitro and in vivo. CSN6 stabilized β-catenin and facilitated the epidermal-to-mesenchymal transition (EMT) in PTC cells. CSN6 positively regulated β-catenin expression in a β-Trcp-dependent manner and triggered expression of several EMT-related genes regulated by β-catenin. CSN6 silencing sensitized PTC cells to FH535 therapy via downregulation of the Wnt/β–catenin signaling pathway. Finally, in PTC patients, the level of CSN6 was significantly (inversely) correlated with tumor size, the presence of multifocal lesions, and TNM stage.CSN6 overexpression in PTC is a strong indicator of enhanced tumor aggressiveness. CSN6 promotes PTC progression by inducing the EMT. CSN6 knockdown sensitizes PTC cells to FH535 therapy via downregulation of the Wnt/β–catenin signaling pathway.
Thyroid Cancer Saturday Poster Translational
GENOMIC LANDSCAPE OF HURTHLE CELL CARCINOMA
We describe a comprehensive genomic characterization of 56 primary Hurthle cell cancers that span the spectrum of tumor behavior. Tumor and matched normal specimens were obtained from 56 patients with primary HCC. Tumors were classified into minimally invasive (n = 24) or widely invasive (n = 32). Whole exome sequencing was used to identify somatic mutations. Copy number changes were identified using FACETS and validated by FISH. RNASeq was used to identify novel fusions genes and to identify differentially expressed genes. Genomic alterations associated with histological phenotype were identified. Genomic changes associated with recurrence and survival were identified by the Kaplan Meier method. We identify novel recurrently mutated genes. Alterations in the RAS/RAF/MAPK and PI3K/AkT/MTOR pathway occurred in 55% tumors, DNA damage and DNA repair pathways in 38% of tumors and epigenetic modification mutations in 59% of tumors. TERT promoter mutations were found in 22% tumors and were more common in the widely invasive phenotype (32% vs 5%). 63% of tumors harbored a non-silent mutation to mitochondrial DNA with an enrichment for Complex I subunits. Copy number analysis identified 3 types of tumors: diploid, near haploid or polysomic. In general, the majority of the minimally invasive cancers were diploid with a small number of near haploid tumors or polysomic tumors. In contrast, the majority of the more aggressive widely invasive cancers were polysomic. In the polysomic tumors, there was whole chromosomal duplication of chromosome 7 with uniparental disomy of other chromosomes. Whole chromosomal duplication of chromosome 7 was associated with poorer outcome. 9 recurrent novel fusion genes were identified by RNASeq. Unsupervised clustering of the 200 most variant genes revealed 2 main groups, A and B. Group A was enriched the majority of recurrences and deaths. Pathway alterations which differentiated these 2 groups were EIF2 signaling, regulation of EIF4 and p70S6K signaling, mTOR signaling as well as alterations in mitochondrial dysfunction and oxidative phosphorylation. These data will facilitate the development of new diagnostic and therapeutic modalities for this very understudied but deadly cancer.
Thyroid Cancer Saturday Poster Translational
INVOLVEMENT OF THE ARYL HYDROCARBON RECEPTOR (AHR) IN THYROID CELL TRANSFORMATION
The Aryl hydrocarbon Receptor (AhR) is overexpressed by many tumors and involved in the tumorigenic process. Kynurenine produced by the IDO enzymatic activity of the tumor microenvironment, contributes to immune tolerance and motility and growth of cancer cells by binding AhR expressed by T lymphocytes and transformed cells, respectively. Very recently, we demonstrated that IDO is overexpressed by thyroid carcinomas. Aim of our work was to evaluate expression and function of AhR in thyroid carcinomas. AhR expression and function was evaluated in thyroid carcinoma samples (90 PTC, 11 MTC, 5 ATC) and in human thyroid carcinoma-derived cell lines. In first instance, the results of our study demonstrated that also AhR is overexpressed in all thyroid carcinoma histologies compared to normal thyroid, either as mRNA (p < 0.00001) or protein. In detail, IHC showed cancer cell staining with three major patterns: low, high and heterogeneous expression. Interestingly, a significant association between mRNA expression of AhR and of its transcriptional target CYP1B1 could be detected (p = 0.004) that indicated the functional activation of AhR in the tumor samples.
Moreover, among the analyzed human thyroid carcinoma-derived cell lines, the FTC133 line showed the coexistence of IDO and AhR overexpression and of spontaneous Kynurenine overproduction. Thus, it appeared as an ideal cellular model to study the function of AhR in thyroid cancer. For this purpose, we selected two agonist of the receptor, kynurenine and ITE, known to exploit different key interactions with distinct set of fingerprint residues. Treatment of the cells with both agonists for up to 24 hours resulted in a general activation of the receptor as demonstrated by an equal mRNA up-regulation of the AhR transcriptional target CYP1B1. At variance, the two compounds regulated differently stemness markers, EMT markers, IDO and AHR expression and cellular motility. In detail, at 24 hours kynurenine induced an upregulation of OCT4, SLUG, FN-1, N-Cadherin, IDO, AHR and cell motility. Conversely, ITE down-regulated all these functions. These data indicate a role for the AhR-kynurenine complex in thyroid transformation and its potential value as novel therapeutic target.
Thyroid Cancer Saturday Poster Clinical
SURGICAL CONFIRMATION OF INCOMPLETE TREATMENT FOR PRIMARY THYROID CARCINOMA BY PERCUTANEOUS THERMAL ABLATION: A RETROSPECTIVE STUDY FROM FUSCC
Recently, thermal ablation has been proposed for treating primary thyroid cancer, triggering an extensive debate. Our study aimed to analyze surgical outcomes of post-ablation cases to investigate the effectiveness and safety of thermal ablation in primary thyroid cancers. We retrospectively searched for patients who accepted surgeries after thermal ablation at diagnosis of primary thyroid cancer at Fudan university Shanghai Cancer Center (FUSCC) prior to August 2017. The patients met the following criteria: (1) undergoing ablation on thyroid nodules suspicious for thyroid cancer, (2) no thyroid history before ablation, (3) accepting surgeries after ablation, (4) availability of adequate medical records. We abstracted the clinicopathological data from the selected patients' records for analysis. Moreover, a systematic review of literature was made to perform a pooled analysis of the relevant cases. Twelve patients with average age of 41.2 ± 13.7 years constituted the FUSCC cohort in our study. In the FUSCC cohort, nineteen out of twenty-one foci with mean size of 1.2 ± 0.7 cm were ablated incompletely. Intraoperatively, we observed adhesion of ablated foci with infrahyoid muscle in four cases. Infrahyoid muscle was found to be cauterized in four cases, and notably the recurrent laryngeal nerve was involved in one case. Residual tumors were confirmed in all cases of the FUSCC cohort by histopathology. The rates of pT1a, pT1b, pT2 and pT3b were 25.0%, 33.3%, 25.0% and 16.7%, and lymph node metastasis (LNM) was found in 66.7% of all cases. Moreover, eight studies were obtained to perform a pooled analysis, which consisted of three prospective studies and five retrospective studies, and nineteen cases were included. Ten out of the nineteen cases (52.6%) were confirmed to have residual tumors by histopathology, and interestingly two of the nine cases without post-ablation residual tumor were finally diagnosed with incidental PTC. And, the incidence of LNM was 36.8% (7/19). In our study, a high incidence of residual tumor and LNM was confirmed in post-ablated thyroid cancer cases, and we suggested thermal ablation should be cautiously recommended in treatment of operable patients with primary thyroid cancer.
Thyroid Cancer Saturday Poster Clinical
INCREASED CANCER RISK IN THYROID NODULES WITH PAPILLARY FEATURES AND AN ATYPIA OF UNDETERMINED SIGNIFICANCE OR FOLLICULAR LESION OF UNDETERMINED SIGNIFICANCE CYTOPATHOLOGICAL DIAGNOSIS
The Bethesda System for Reporting Thyroid Cytopathology (BSRTC) is a standardized method that pathologists utilize for reporting thyroid fine needle aspiration biopsy (FNAB) cytology, allows for preoperative risk of malignancy (ROM) estimation, and influences extent of surgery. The objective of this study was to evaluate the influence of papillary features on ROM within the Atypia of Undetermined Significance or Follicular Lesion of Undetermined Significance (AUS-FLUS) BSRTC diagnostic category. A Retrospective review of the records of all individuals undergoing preoperative FNAB and thyroidectomy, between 2010 and 2016, at a single high volume hospital, was carried out. Those cases with an AUS-FLUS diagnosis were identified and sub-classified based upon the presence of papillary features. A subset of AUS-FLUS cases underwent expert cytopathological review to determine concordance with reported characteristics. For the entire study population of 504 cases there were 111 cases (22.0%) that had an FNAB AUS-FLUS diagnosis. The overall risk of malignancy for the AUS-FLUS category was 34.2%. Papillary features were identified in 53 FNAB specimens (47.7% of the AUS-FLUS cases or 10.5% of the entire study population) and had a 47.1% ROM. The 58 FNAB specimens (52.3%) that did not exhibit papillary features had a significantly lower ROM (22.4%) (p = 0.0089). The presence of papillary features in a thyroid FNAB with an AUS-FLUS diagnosis is common, and is associated with a higher ROM then is currently suggested by the BSRTC. Preoperative patient counseling and extent of surgery should be influenced by the presence of papillary features.
Thyroid Cancer Saturday Poster Clinical
RE-CONSIDERATION ABOUT THE CRITERION OF EXCELLENT RESPONSE IN DTC PATIENTS
According to the American Thyroid Association (ATA) guideline in 2015, besides negative imaging, both an unstimulated thyroglobulin (u-Tg) below 0.2ng/ml and a stimulated Tg (s-Tg) below 1.0ng/ml were recommended to define Excellent Response (ER). This study aimed to investigate whether a u-Tg below 0.2ng/ml coincides with a s-Tg below 1ng/ml. A number of 290 non-metastatic DTC patients were retrospectively evaluated with a median follow-up of 36 months. The level of s-Tg were observed in patients whose u-Tg levels were below 0.2ng/ml after radioiodine therapy, and risk factors associated with increasing of s-Tg to above 1ng/ml from below 0.2ng/ml were analyzed. Results: Among the 290 non-metastatic DTC patients, 52.8% (153 cases) achieved a u-Tg below 0.2ng/ml 3 months after remnant ablation, most of whom (83.7%, 128/153) further satisfied a s-Tg below 1ng/ml in the following measurements of s-Tg 6 months after radioiodine (RAI) therapy. Multivariate analysis showed that the level of TSH (P = 0.038) was the only influence factors that increased Tg from below 0.2ng/ml to above 1ng/ml after thyroxin withdrawal. In a further subgroup analysis about the influence of thyrotropin (TSH) on s-Tg (n = 43), we evaluated s-Tg at different TSH levels in 43 patients with u-Tg below 0.2ng/ml, a higher level of TSH (118.23 ± 30.72 mIU/ml vs. 59.99 ± 26.12mIU/ml) increased s-Tg in 88.4% patients (P = 0.00), which caused more patients (from 18.6% to 30.2%) increased their s-Tg to above 1ng/ml after thyroxin withdrawal. Conclusion: u-Tg might be the better choice in the definition of ER for it is more stable, convenient, economical specialty, without hypothyroidism side effect.
Thyroid Cancer Saturday Poster Clinical
ULTRASOUND-GUIDED PERCUTANEOUS ETHANOL ABLATION THERAPY FOR FIFTEEN PATIENTS WITH PAPILLARY THYROID MICROCARCINOMA: A NOVEL, EFFECTIVE AND WELL TOLERATED ALTERNATIVE TO NECK SURGERY OR OBSERVATION
Perhaps due to a current global epidemic of “overdiagnosis”, papillary thyroid microcarcinoma (PTM) is now the commonest endocrine malignancy (BMJ 348: 3045, 2014). Current management options vary from lobectomy or total thyroidectomy to “active surveillance”. An alternative approach, used successfully for eliminating neck nodal metastases, (JCEM 96:2717, 2011) is ultrasound-guided percutaneous ethanol ablation (UPEA). Here we present our experience of treating with UPEA 17 biopsy-proven tumor foci in 15 PTM patients. Study patients (10F, 5M) were aged, at time of UPEA, 36-86 years (median 51 years); 4 had significant co-morbidities. The seventeen tumors (two multicentric) varied from 4-10 mm diameter. Tumor volumes ranged from 25-375 cu mm (mean 132). UPEA technique (local anesthetic, outpatient) and follow-up protocol were as previously described (Surgery 154: 1448, 2013). The first patient had under ultrasound guidance only a single injection of 0.2 cc of 98% ethanol directly into his tumor focus (8mm diameter; 233 cu mm volume). Subsequently, patients 2-15 had two injections on consecutive days; total ethanol volume injected ranged from 0.45 to 1.45 cc (mean 1.0 cc). Five of these 17 tumors (29%), which had <50% tumor shrinkage, had a 3rd injection at 3-5 months. All patients were followed with neck ultrasound scans, with recalculation of tumor volume and assessment of tumor-associated Doppler flow at each visit.14 patients to date have been followed for 4-81 months (mean 28 months). No patient developed after UPEA a painful thyroiditis; none had hoarseness or hypocalcemia. All tumor foci have shrunk and Doppler flow eliminated. Mean tumor volume reduction in the 16 tumor foci was 85% (range 49-100%); 8 tumors (50%) were no longer identifiable by sonography after being followed for an average of 10 months (range 4-17 months). UPEA for PTM was well tolerated and was substantially (>37,000 US dollars) cheaper than conventional surgery. Our results would suggest that, for PTM patients who do not wish neck surgery and are uncomfortable with “active surveillance”, UPEA likely represents an attractive and “minimally invasive” definitive management option.
Thyroid Hormone Action Saturday Poster Clinical
USING I-131 THERAPY FOR GRAVES' DISEASE: SUCCESS AND THYROID HORMONE OUTCOMES IN PATIENTS AT A SINGLE INSTITUTION
Radioactive iodine ablation (RAI) with I-131 for definitive management of Graves' disease is commonly used as a non surgical and often preferred treatment. Although there are guidances for dose calculation and monitoring after the therapy, the success rates and trends in thyroid hormones after the I-131 therapy remain variable. Currently, a 3-6 month monitoring period after the RAI is recommended to detect hypothyroidism needing thyroid hormone replacement or persistent hyperthyroidism which may warrant further treatment.
Thyroid Imaging Saturday Poster Clinical
THYROID ULTRASOUND MALIGNANCY SCORE (TUMS), A MACHINE LEARNING MODEL TO PREDICT THYROID MALIGNANCY FROM ULTRASOUND FEATURES
Once relevant features are entered, the website will calculate malignancy probability based on the experience at our institution as described above. If sufficient information is entered, it will also calculate risk based on the ATA guideline. Machine learning algorithms can be used to create clinically useful models to predict thyroid cancer risk based on a nodule's US features. TUMScore model prediction reliability could be improved by adding more data from other populations to the model. If the high negative predictive value for this model withstands validation, it could be used as a screening tool to select patients for biopsy. Further multicenter studies are needed to validate this system before it can be used in clinical practice.
Thyroid Imaging Saturday Poster Clinical
FAMILIAL PAPILLARY THYROID CARCINOMA NODULES PRESENT A MILD ULTRASOUND APPEARANCE COMPARED WITH SPORADIC PAPILLARY THYROID CARCINOMA
In recent years, numerous reports have indicated the presence of familial papillary thyroid carcinoma (FPTC), but the ultrasonic characteristics of FPTC nodules are not well established. The overall aim of this study was to analyze the clinicopathological and ultrasonic features of FPTC. One hundred thirty-six patients with FPTC were enrolled as the study group, and one hundred seventy-seven patients with sporadic PTC were enrolled as controls; the subjects were all pathologically confirmed to exhibit papillary thyroid carcinoma from January 2009 to July 2016 in our hospital. We compared the differences in the clinicopathological and ultrasonic features between the two groups. FPTC was smaller in tumor size and more multifocal and invasive than the sporadic cases were. Nodules with FPTC had a less irregular shape and infiltrative margin, fewer microcalcification ultrasonic features (p < 0.05), a lower ATA risk and a lower TI-RADS classification than did nodules with sporadic PTC (p < 0.05). The same results were present in nodules sized <2.0 cm in the FPTC group. A less irregular shape and infiltrative margin and fewer microcalcifications were present in the FPTC group (p < 0.05) in both the classic PTC and FV-PTC group, and less hypoechogenicity and a lower ATA risk were also exhibited in the FPTC group with FV-PTC. Nodules in FPTC patients with three or more affected members showed a lower ATA and TI-RADS risk than did nodules of FPTC patients with two affected members. FPTC is more aggressive than sporadic PTC. FPTC nodules present fewer malignant ultrasound features, and the nodules of more-affected patient families show a less malignant ultrasound appearance. More invasive and malignant biological behaviors in genetic traits must be identified and investigated further. We should take careful family histories and be more conscious of the early detection of FPTC.
Thyroid Imaging Saturday Poster Clinical
OVERVIEW OF CLINICAL INDICATION FOR THYROID ULTRASOUND
Thyroid Ultrasound (US) imaging is a helpful resource that can assess the characteristics of the thyroid gland and help identify nodules with potential for malignancy. Currently, there are different criteria for the clinical utility of US by the American Institute of Ultrasound Medicine (AIUM) in contrast to the American Thyroid Association (ATA). Clinical indication for US becomes essential as increased imaging may exhaust resources for benign or pseudo-nodules. For the purpose of our study, we wanted to evaluate our physician population when ordering thyroid US in addition to the workup before and after imaging. A retrospective chart review was performed on 74 thyroid US request at the University Hospital in San Antonio, TX by primary/subspecialty physicians. Charts were reviewed by the clinical indication for US classified by: Abnormal TFTs, Palpated nodule, Goiter, Incidental finding or Other. Subsequent analysis was pursued in regards to the number of thyroid nodules that underwent fine need aspiration with cytology determined by the Bethesda system. Of the 74 patients evaluated for initial thyroid US imaging, there was a predominance of the female gender nearly 80% (59/74) as opposed to only 20% men (15/74). Request for US imaging was ordered mostly by primary care physicians (PCPs) 69% (51/74) as opposed to specialist 24% (18/74). In regards to the clinical indication for imaging, goiter was the most common entity at 45% (33/74). Following goiter, subsequent indications were as followed: palpated nodule 20% (15/74), other 20% (15/74), abnormal TFTs 11% (8/74) and incidental finding 4% (3/74). Of note, 45 thyroid nodules were newly diagnosed in which only 27% (12/45) were biopsied with no evidence of follicular neoplasm, suspicion for malignancy or occult malignancy identified. PCPs were most likely to order initial thyroid US imaging with clinical indication of goiter. Subsequently, approximately 60% of these patients were identified with newly diagnosed thyroid nodules. With high prevalence of thyroid nodules, it is important to effectively utilize US imaging as the increased rate of incidental findings may lead to unnecessary procedures driving increasing health care cost and patient anxiety.
Thyroid Nodules & Goiter Saturday Poster Clinical
THYROID NO SURGERY TUMOR ABLATION: BREAKTHROUGH METHODS AND TECHNOLOGY ARE HERE
From a surgical society called the American Goiter Association to the present ATA, the slowest changes were noted in the development of alternative procedures to surgery. Still to this day many patients are referred to the surgeon for benign thyroid nodules, recurrent nodal neck cancer, and thyroid and parathyroid cysts even though we have had first line non-surgical treatment ethanol ablation PEI available. The addition of another non-invasive method called thyroid radiofrequency ablation TFRA is coming to North America this year. Prior RFA systems in the US have been aimed at other organs. The electrode probe was too long and too thick for delicate thyroid area. Studies in Korea lead by Professor JH Baek have developed thyroid specific systems for thyroid ablation. These include 3,5,7 mm cooled hot tips, #18 and 19 electrodes on a short 7 cm cooled probe, bipolar system for use in pregnant females and patients with pacemakers. Professor Baek and his team developed a needle tracking system to train new ablation physicians locate the tip of the electrode. His IV dextrose injection between danger structures and the target mass decreases complications. The ablation of local arteries and veins acting as a heat sink is just one more advance. Between 2014–2017 in the buildup to release of these thyroid friendly systems and methods in the USA I have trained in RFA and more important sent my patients for TRFA out of the country. The results have been dramatic.
There have been no complications in my returning patients. Size and cosmetic problems were removed or lessened. All were happy to avoid surgery and to be free from the daily ingestion of thyroid hormone. One patient with massive complex cystic goiter and co-morbid problems had her symptoms decreased with combination PEI/TRFA.
1. Interventional thyroidologists are now going to armed with two potent alternatives to thyroid surgery.
2. PEI is an under-utilized less expensive treatment alternative that endocrinologists need to adopt as their own.
3. PEI is now a potential treatment for primary micro-papillary cancer as alternative to surgery and active surveillance.
4. PEI or TRFA treatment is almost never a cause of a lifetime need for thyroid hormone replacement.