Search

Whether preoperative F-18 fluorodeoxyglucose ( FDG)-positron emission tomography/computed tomography ( PET/ CT) can predict recurrence of papillary thyroid carcinoma ( PTC) remains unclear. Herein, we evaluated the potential of primary tumor FDG avidity for the prediction of tumor recurrence in PTC patients. A total of 412 PTC patients (72 males, 340 females; age: 47.2 ± 12.2 years; range: 17-84 years) who underwent FDG- PET/ CT prior to total thyroidectomy ( n = 350), subtotal thyroidectomy ( n = 2), or lobectomy ( n = 60) from 2007 to 2011 were analyzed. The predictive ability for recurrence was investigated among various clinicopathological factors, BRAFV600E mutation, and preoperative FDG avidity of the primary tumor using Kaplan-Meier (univariate) and Cox proportional hazards regression (multivariate) analyses. Of the 412 patients, 19 (4.6%) experienced recurrence, which was confirmed either by pathology ( n = 17) or high serum thyroglobulin level ( n = 2), during a mean follow-up period of 43.9 ± 16.6 months. Of the 412 patients, 237 (57.5%) had FDG-avid tumors (maximum standardized uptake value, 7.1 ± 7.0; range: 1.6-50.5). Kaplan-Meier analysis revealed that tumor size ( P = 0.0054), FDG avidity of the tumor ( P = 0.0049), extrathyroidal extension ( P = 0.0212), and lymph node ( LN) stage ( P < 0.0001) were significant predictors for recurrence. However, only LN stage remained a significant predictor in the multivariate analysis ( P < 0.0001). Patients with FDG-avid tumors had higher LN stage ( P < 0.0001), larger tumor size ( P < 0.0001), and more frequent extrathyroidal extension ( P < 0.0001). In conclusion, FDG avidity of the primary tumor in preoperative FDG- PET/ CT could not predict the recurrence of PTC. LN stage was the only identified predictor of PTC recurrence. [ABSTRACT FROM AUTHOR]