The most widely used diagnostic nuclear medicine technique in well-differentiated thyroid cancer (DTC) is radioiodine scintigraphy, either diagnostic or post-therapeutic, together with serum thyroglobulin (Tg) measurement; this combination is usually able to determine the presence or absence of cancer. FDG-PET has shown less sensitivity in DTC that retains the ability to trap 131I. Several alternative procedures with single photon emitting radiopharmaceuticals have been evaluated including whole body scan with 201TI, 99mTc-sestamibi or tetrofosmin scan, with different sensitivity and specificity. The main advantage of these tests is that their results are not influenced by the levels of TSH, therefore they do not require a hypothyroid state in the patient. Recently positron emission tomography (PET) with FDG has been demonstrated to be highly useful in thyroid cancer patients with a negative 131l whole body scan but measurable Tg. According to reports in the literature FDG-PET in the follow-up of operated patients has a sensitivity ranging from 70% to 90% in identifying the source of Tg. The demonstration of lesions can lead to a change in treatment including surgery or external radiation instead of radioiodine treatment. In Europe, medullary thyroid cancer (MTC) is currently visualized by 99mTc pentavalent dimercaptosuccinic acid (DMSA) and 99mTc-sestamibi or tetrofosmin. Metaiodobenzylguanidine (MIBG) radiolabeled with 123I or 131I is another reliable radiopharmaceutical for medullary tumors. 111In-pentetreotide scan is positive in a high percentage of patients because MTC expresses somatostatin receptors. FDG-PET has an interesting role to play in calcitonin-positive patients, where PET has been shown to correctly identify lesions in cervical and mediastinal lymph nodes as well as at distant sites. Furthermore, calcitonin-guided PET has been found to be superior to CT and MRI in many patients. Recent reports indicated that 18F-DOPA scan in MTC seems to be more accurate than FDG-PET.
DietleinM., DressierJ., EschnerW., LeisnerB., ReinersC., SchichaH.: Procedure guideline for iodine-131 whole-body scintigraphy for differentiated thyroid cancer (version2*). Nuklearmedizin, 42: 123–125, 2003.
2.
NakadaK., KatohC., KanegaeK., TsukamotoE., ShigaT., MochizukiT., ItohK., TamakiN.: Thallium-201 scintigraphy to predict therapeutic outcome of iodine-131 therapy of metastatic thyroid carcinoma. J Nucl Med, 39: 807–810, 1998.
3.
YenT.C., LinH.D., LeeC.H., ChangS.L., YehS.H.: The role of technetium-99m sestamibi whole-body scans in diagnosing metastatic Hürthle cell carcinoma of the thyroid gland after total thyroidectomy: a comparison with iodine-131 and thallium-201. Eur J Nucl Med, 21: 980–983, 1994.
4.
GallowitschH.J., MikoschP., KresnikE., UnterwegerO., GomezI., LindP.: Thyroglobulin and low dose iodine-131 and technetium-99m-tetrofosmin whole-body scintigraphy in differentiated thyroid carcinoma. J Nucl Med, 39: 870–875, 1998.
5.
BaudinE., SchlumbergerM., LumbrosoJ., TravagliJ.P., CaillouB., ParmentierC.: Octreotide scintigraphy in patients with differentiated thyroid carcinoma; contribution for patients with negative radioiodine scans. J Clin Endocrinol Metab, 81: 2541–2544, 1996.
6.
LindP., KumnigG., MatschnigS., HeinischM., GallowitschH.J., MikosP., KresnikE., GomezI., UnterwegerO.: The role of F-18FDG PET in thyroid cancer. Acta Med Austriaca, 27: 38–41, 2000.
7.
GrunwaldF., BrieleB., BiersackH.J.: Non-131I-scintigraphy in the treatment and follow-up of thyroid cancer. Single-photon-emitters or FDG-PET? Q J Nucl Med, 43: 195–206, 1999.
8.
AdamsS., BaumR.P., HertelA., Schumm-DraegerP.M., UsadelK.H., HorG.: Comparison of metabolic and receptor imaging in recurrent medullary thyroid carcinoma with histopathological findings. Eur J Nucl Med, 25: 1277–1283, 1998.
9.
O'ByrneK.J., O'HareN., SweeneyE., FreyneP.J., CullenM.J.: Somatostatin and somatostatin analogues in medullary thyroid carcinoma. Nucl Med Commun, 17: 810–816, 1996.
10.
WiesnerW., EngelH., von SchulthessG.K., KrestinG.P., BickI.: FDG PET-negative liver metastases of a malignant melanoma and FDG-positive Hürthle cell tumor of the thyroid. Eur Radiol, 9: 975–978, 1999.
11.
Brandt-MainzK., MullerS.P., GorgesR., SallerB., BockischA.: The value of fluorine-18 fluorodeoxyglucose in patients with medullary thyroid cancer. Eur J Nucl Med, 27: 490–496, 2000.
12.
MazzaferriE.L.: Management of a solitary thyroid nodule. N Engl J Med, 328: 553–559, 1993.
13.
GharibH., GoellnerJ.R.: Fine-needle aspiration biopsy of the thyroid: an appraisal. Ann Intern Med, 118: 282–289, 1993.
UematsuH., SadatoN., OhtsuboT., TsuchidaT., NakamuraS., SugimotoK., WakiA., TakahashiN., YonekuraY., TsudaG., SaitoH., HayashiN., YamamotoK., IshiiY.: Fluorine-18-fluorodeoxyglucose PET versus thallium-201 scintigraphy evaluation of thyroid tumors. J Nucl Med, 39: 453–459, 1998.
16.
ReimerS., AdlerL.P., BloomA.D.: Prospective evaluation of PET-FDG in FNA indeterminate thyroid nodules. J Nucl Med, 39: 123, 1998.
17.
YasudaS., ShohtsuA.: Cancer screening with whole-body 18F-fluorodeoxyglucose positron-emission tomography. Lancet, 350: 1819, 1997.
18.
YasudaS., ShohtsuA., IdeM., TakagiS., TakahashiW., SuzukiY., HoriuchiM.: Chronic thyroiditis: diffuse uptake of FDG at PET. Radiology, 207: 775–778, 1998.
19.
LawsonM.A., ChenK., SeaboldJ.E.: Incidental thyroid metabolomas: focal FDG thyroid gland uptake observed in patients undergoing PET imaging for metabolic assessment of pulmonary nodules, tumor staging and evaluation of cancer recurrences. Thyroid, 2003 (submitted).
20.
DietleinM., ScheidhauerK., VothE., TheissenP., SchichaH.: Fluorine-18 fluorodeoxyglucose positron emission tomography and iodine-131 whole-body scintigraphy in the follow-up of differentiated thyroid cancer. Eur J Nucl Med, 24: 1342–1348, 1997.
21.
ChungJ.K., SoY., LeeJ.S., ChoiC.W., LimS.M., LeeD.S., HongS.W., YounY.K., LeeM.C., ChoB.Y.: Value of FDG PET in papillary thyroid carcinoma with negative 131I whole-body scan. J Nucl Med, 40: 986–992, 1999.
22.
ContiP.S., DurskiJ.M., BacqaiF., GraftoS.T., SingerP.A.: Imaging of locally recurrent and metastatic thyroid cancer with positron emission tomography. Thyroid, 9: 797–804, 1999.
23.
WangW., MacapinlacH., LarsonS.M., YehS.D., AkhurstT., FinnR.D., RosaiJ., RobbinsR.J.: PET scanning with [18F] 2-fluoro-2 deoxy-D-glucose (FDG) can localize residual differentiated thyroid cancer in patients with negative [131I]-iodine whole-body scans. J Clin Endocrinol Metab, 84: 2291–2302, 1999.
24.
AltenvoerdeG., LerchH., KuwertT., MathejaP., SchafersM., SchoberO.: Positron emission tomography with F-18-deoxyglucose in patients with differentiated thyroid carcinoma, elevated thyroglobulin levels, and negative iodine scans. Langlebecks Arch Surg, 383: 160–163, 1998.
25.
JadvarH., McDougallI.R., SegallG.M.: Evaluation of suspected recurrent papillary thyroid carcinoma with [18F] fluorodeoxyglucose positron emission tomography. Nucl Med Comm, 19: 547–554, 1998.
26.
HuangT.S., ChiengP.U., ChangC.C., YenR.F.: Positron emission tomography for detecting iodine-131 nonvisualized metastasis of well-differentiated thyroid carcinoma: two case reports. J Endocrinol Invest, 21: 392–398, 1998.
27.
Van TolK.M., JagerPl, DullaartR.P.F., LinksT.P.: Follow-up in patients with differentiated thyroid carcinoma with positive 18F 2-fluoro-2 deoxy-D-glucose positron emission tomography results, elevated thyroglobulin levels, and negative high-dose 131I post-treatment whole-body scans. J Clin Endocrinol Metab, 85: 2082–2083, 2000.
28.
AlnafisiN.S., DriedgerA.A., CatesG., MooteD.J., RaphaelS.J.: FDG PET of recurrent or metastatic 131I-negative papillary thyroid carcinoma. J Nucl Med, 41: 1010–1015, 2000.
29.
MurosM.A., Llamas-ElviraJ.M., Ramirez-NavarroA., GomezM.J., Rodriguez-FernandezA., MurosT., Lopez de la TorreM., BecerraA., CarrerasJ.L.: Utility of fluorine-18-fluorodeoxyglucose positron emission tomography in differentiated thyroid carcinoma with negative radioiodine scans and elevated serum thyroglobulin levels. Am J Surg, 179: 457–461, 2000.
CookG.J.R., MaiseyM.N., FogelmanI.: Normal variants, artefacts and interpretative pitfalls in PET with 18-fluoro-2-deoxyglucose and carbon-11 methionine. Eur J Nucl Med, 26: 1363–1378, 1999.
32.
BarringtonS.F., MaiseyM.N.: Skeletal muscle uptake of fluorine-18 FDG; effect of oral diazepam. J Nucl Med, 37: 1127–1129, 1996.
33.
SissonJ.C., AckermanR.J., MeyerM.A., WahlR.L.: Uptake of 18-fluoro-2-deoxy-D-glucose by thyroid cancer: implications for diagnosis and therapy. J Clin Endocrinol Metabol, 77: 1090–1094, 1993.
34.
PetrichT., BornerA.R., OttoD., HofmannM., KnappW.H.: Influence of rhTSH on [(18)F]fluorodeoxyglucose uptake by differentiated thyroid carcinoma. Eur J Nucl Med Mol Imaging, 29: 641–647, 2002.
35.
MusholtT.J., MusholtP.B., DehdashtiF., MoleyJ.F.: Evaluation of fluorodeoxyglucose-positron emission tomography scanning and its association with glucose transporter expression in medullary thyroid cancer and pheochromocytoma: a clinical and molecular study. Surgery, 122: 1049–1060, 1997.
