FES mean standardized uptake value is a prognostic marker for patients with endometrial carcinoma

Objectives: The purpose of this study was to evaluate the prognostic value of pretreatment 16α-[¹⁸F]-fluoro-17β-estradiol (¹⁸F-FES) uptake in patients with endometrial carcinoma. A total of 72 patients with the International Federation of Gynecology and Obstetrics (FIGO) stage I-IV endometrial carcinoma underwent ¹⁸F-FES and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) before treatment. Mean standardized uptake value (SUV_mean) of the primary tumor was compared with histological prognostic factors and the relationships between SUV_mean and progression-free survival (PFS) or overall survival (OS) were examined. Patient follow-up continued for at least 24 months until 60 months after starting treatment, or death. Patients were divided into two groups according to ¹⁸F-FES SUV (≥2.63 versus <2.63). The Kaplan-Meier survival graph showed that patients with low ¹⁸F-FES SUV had significantly poor PFS (p<0.001) and OS (p<0.001) than patients with high SUV, while ¹⁸F-FDG showed no significant differences. In multivariate analyses, ¹⁸F-FES SUV <2.63 (p=0.021, hazard ratio (HR) 6.214, 95% confidence interval (CI) 1.321-29.223) and FIGO stage (p=0.008, HR 5.374, 95%CI 1.548-18.652) were significantly associated with PFS. Pretreatment ¹⁸F-FES uptake measured as SUV_mean can be useful for predicting outcome in patients with EC. These measurements might therefore assist in the individualized management of patients.