TY - JOUR T1 - <sup>18</sup>F-FDG PET in the Diagnosis and Follow-up of Thyroid Malignancy JF - In Vivo JO - In Vivo SP - 109 LP - 114 VL - 22 IS - 1 AU - A. AL-NAHHAS AU - S. KHAN AU - A. GOGBASHIAN AU - E. BANTI AU - L. RAMPIN AU - D. RUBELLO Y1 - 2008/01/01 UR - http://iv.iiarjournals.org/content/22/1/109.abstract N2 - The diagnosis of carcinoma of the thyroid is usually made in the process of investigating a thyroid nodule with clinical examination, Technetium-99m scan, ultrasonography and fine-needle aspiration (FNA) cytology. The follow-up is mainly based on 123-iodine and 131-iodine scans and serum thyroglogulin measurement. The aim of the present review was to establish the role of 18F-FDG PET in the differential diagnosis of doubtful thyroid nodules and in the follow-up of patients with increased serum thyroglobulin levels and negative iodine-scan. It remains to be defined if metabolic imaging with PET could be a useful routine procedure in the management of thyroid tumours since the majority of them are well-differentiated and therefore have less avidity to 18F-FDG. In the present work we collected the specific literature derived from MEDLINE over the last 10 years to clarify the potential clinical value of 18F-FDG PET in thyroid malignancies. An emerging role for 18F-FDG PET is in the assessment of incidental finding of a thyroid nodule which, when showing high FDG uptake should be regarded as a possible malignancy that needs further assessment. Another well-documented role for 18F-FDG PET is in the investigation of cases of established well-differentiated thyroid carcinomas presenting with high thyroglobulin and negative iodine imaging. An increase of the 18F-FDG uptake in these tumours indicates a shift towards lesser differentiation (with more aggression and poor prognosis) and may benefit from alternative management. 18F-FDG PET can be considered a routine functional imaging method in detecting iodine-negative recurrent disease in thyroid cancer patients with elevated serum thyroglobulin levels during follow-up. 18F-FDG PET seems to be useful also in differential diagnosis of suspected thyroid nodules, especially using the semi-quantitative SUV analysis. Copyright © 2008 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved ER -