Prognostic value of preoperative metabolic tumor volume measured by ¹8F-FDG PET/CT and MRI in patients with endometrial cancer.

ABSTRACT

OBJECTIVE: Tumor metabolic activity is a significant prognostic factor for endometrial cancer; however, there are few reports on the clinical importance of metabolic tumor volume (MTV) in patients with endometrial cancer. Therefore, we evaluated the prognostic value of preoperative MTV measured by (18)F-FDG PET/CT and MRI in a group of these patients. METHODS: We retrospectively reviewed patients with pathologically proven endometrial cancer who had undergone preoperative (18)F-FDG PET/CT and MRI scans. The prognostic significance of PET/CT parameters and other clinicopathological variables was evaluated. RESULTS: A total of 76 consecutive patients were included in the study. The median follow-up duration was 27 mo (range 3 to 96 mo) after surgery. MTV was correlated with FIGO stage and SUVmax. Age and FIGO stage were independent prognostic factors for recurrence in the multivariate analysis. In the subgroup analysis for 62 patients with endometrioid endometrial cancer, age (hazard ratio 1.098, P = 0.007, 95% confidence interval (CI) 1.026-1.175) and an MTV index of ≥ 876.4 (hazard ratio 5.795, P = 0.032, 95% CI 1.160-28.958) were determined to be independent prognostic factors of recurrence, and there was a statistically significant difference in progression-free survival (PFS) between patients in the high MTV and low MTV groups (log-rank test, P = 0.002). CONCLUSION: Preoperative MTV of the primary tumor was an independent prognostic factor for PFS and was significantly associated with recurrence in patients with endometrioid endometrial cancer. MTV is a promising tool for the prediction of outcome in patients with endometrioid endometrial cancer.