Prognostic Value of Metabolic Activity Measured by ¹⁸F-FDG PET/CT in Patients with Advanced Endometrial Cancer

Purpose: We evaluated the potential prognostic value of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in patients with stage IIIC/IV endometrial cancer. Methods: Patients with stage IIIC/IV endometrial cancer who had undergone FDG PET/CT workup for staging were enrolled. Maximum standardized uptake values (SUVmax) measured from regions of interest (ROIs) of the primary tumor (SUVt) and lymph nodes (SUVn) were correlated with overall survival (OS). The SUVn was defined as the highest SUVmax of the metastatic lymph nodes. Survival probability was assessed using the Kaplan-Meier method. Results: A total of 42 patients with a median age of 55.5 years (range 32-76 years) were included. Twenty-nine percent (n = 12) of patients were premenopausal and 71 % (n = 30) were postmenopausal. The average SUVt was 12.9 (range 1.8-36.5), and the average SUVn was 7.3 (range 2.0-22.5). Median follow-up time was 25.9 months (range 1-84 months). Using a SUVt of 9.5 as a cutoff value, two groups with different rates were determined (P = 0.026). In addition, patients with a low SUVn had significantly better OS than those with a high SUVn (P = 0.003). Patients in the International Federation of Obstetrics and Gynecology (FIGO) stage IV group with SUVt ≥ 9.5 or SUVn ≥ 7.3 showed a significantly longer OS than the other groups. Conclusions: FDG uptake of primary endometrial cancer and lymph nodes might be a prognostic factor in advanced endometrial cancer. More aggressive therapy could be considered in patients with stage IV endometrial cancer and high SUVt and/or high SUVn.