succimer and Thyroid-Nodule

Thyroid scans yield functional information useful in the differential diagnosis of thyroid nodules and are usually performed with TcO4-99m for its favourable physical properties, availability, low cost and good correlation with I123. Cold thyroid nodules are very frequent and generally due to benign diseases. To distinguish the minority representing carcinomas, classes of risk must be selected, according to multiple factors, including external radiation exposure, sex, age, iodine intake and thyroid morphology. These patients will undergo fine needle biopsy which can make the final diagnosis. Its accuracy is often preferred as a first line modality in the diagnostic approach to thyroid nodules. Tumour imaging agents are very useful in the staging and follow-up of thyroid carcinomas, but are rarely needed in the primary diagnosis of the disease.

Topics: Antibodies, Monoclonal; Biopsy, Needle; Diagnosis, Differential; Gallium Radioisotopes; Humans; Iodine Radioisotopes; Radionuclide Imaging; Succimer; Thallium Radioisotopes; Thyroid Gland; Thyroid Neoplasms; Thyroid Nodule

Twenty-five patients with solitary cold thyroid nodules (SCN) were studied by fine needle aspiration (FNA) cytology, radionuclide perfusion scanning (RPS) and pentavalent technetium dimercaptosuccinic acid (99m Tc DMSA) scanning, with an aim to distinguish neoplastic from non-neoplastic nodules. All the patients were operated upon and the nodules were subjected to histopathological examination. 13 of the 25 nodules (52%) were malignant (7 papillary carcinomas, 3 medullary thyroid carcinomas and 1 each of follicular carcinoma, insular carcinoma and clinically anaplastic thyroid tumour). The specificity of DMSA scanning and FNA cytology were 100% and that of RPS 60%. The sensitivity of RPS and DMSA scanning were 80% and 20% and that of FNA cytology (using a broad definition of test-positivity), 100%. Additionally, FNA cytology could morphologically type the majority of neoplasms.

Topics: Biopsy, Needle; Diagnostic Imaging; Humans; Organotechnetium Compounds; Perfusion; Radionuclide Imaging; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid; Thyroid Nodule

We report 4 cases of abnormal results using iodine-123 metaiodobenzylguanidine (123I-mIBG) or technetium-99m (V) dimercaptosuccinic acid (99mTc(V)-DMSA) scintigraphy in the diagnosis and follow-up of presumed neuroendocrine tumours. The present series consisted of 2 false-positive cases (1 adenomatous polyp of the caecum with mIBG and 1 follicular adenoma of the thyroid with DMSA) and 2 cases of anomalous uptake of (V)-DMSA in a non-neuroendocrine tissue.

Topics: 3-Iodobenzylguanidine; Adolescent; Adult; Aged; Child; Diagnosis, Differential; Endocrine Gland Neoplasms; Female; Humans; Intestinal Polyps; Iodine Radioisotopes; Iodobenzenes; Organotechnetium Compounds; Radionuclide Imaging; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid; Thyroid Nodule