April - June 2019, Volume 15, Issue 2

Larg MI, Barbus E, Gabora K, Pestean C, Cheptea M, Piciu D

18F-FDG PET/CT in Differentiated Thyroid Carcinoma

Acta Endo (Buc) 2019, 15 (2): 203-208
doi: 10.4183/aeb.2019.203

Aim. Fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) become an important tool in oncology by combining the metabolic information from 18F-FDG PET with the morphological information of CT. The main objective of this study was to assess the diagnostic value of PET/CT in patients with differentiated thyroid carcinoma (DTC). Material and Methods. We analyzed 173 PET/CT scans of patients with DTC presenting elevated thyroglobulin (Tg) levels, negative Tg-antibodies levels, negative Iodine-131 whole-body scanning (I-131 WBS) and without any signs of clinical or other imaging technique for tumor recurrence/metastases. Results. PET/CT scans were positive in 38% of cases (65/173). The sensitivity, specificity, positive predictive values and the accuracy of PET/CT imaging were 88.09%, 98.6%, 93.1% respectively 96.53%. After the PET/CT scan 29 patients underwent surgery, 24 of them continued radio-iodine therapy, 5 patients initiated tyrosine kinase inhibitors treatment and external radiotherapy. Conclusion. 18F-FDG PET/CT is a valuable imaging technique which has the capability of identifying those cases of thyroid recurrence/metastases with elevated Tg levels and negative I-131 WBS. The treatment strategy was changed in 89.2% cases of positive PET/CT scans which shows us that 18F-FDG PET/CT imaging should be integrated into the follow-up programs for DTC patients.

Keywords: 18F-FDG, Differentiated thyroid carcinoma, PET/CT.

Correspondence: Maria Iulia Larg, 34 Republicii Street, Cluj-Napoca, 400015, Romania, E-mail: mariaiulia.larg@yahoo.com