Adjuvant radiation therapy is associated with improved pelvic control and overall survival in FIGO IB endometrial carcinoma with high grade histology

•Patients with high risk histology endometrial carcinoma are at high risk for local-regional relapse.•We identified patients with FIGO IB endometrial carcinoma with clear cell, papillary serous and Grade 3 endometrioid adenocarcinoma.•Adjuvant radiation therapy was associated with improved pelvic control and overall survival.

ObjectiveHigh grade histologies of endometrial carcinomas portend a worse prognosis. Previous randomized, prospective studies examining the role of radiation have excluded endometrial cancer patients with FIGO IB with high risk histologies (clear cell, papillary serous, and Grade 3 endometrioid adenocarcinoma).MethodsWe retrospectively identified 51 patients who underwent a hysterectomy for a FIGO IB endometrial carcinoma with clear cell, papillary serous or Grade 3 endometrioid adenocarcinoma histology. Adjuvant radiation therapy was delivered in 44 of 51 patients (86%). We assessed pelvic control, vaginal control, and overall survival using Kaplan Meier estimate and the log rank test. We completed univariate analysis.ResultsThe 5-year vaginal control rate in patients without and with adjuvant radiation therapy was 67% and 93.3%, respectively (p = 0.0066). At 5-years, the pelvic control rate in patients without and with adjuvant radiation therapy was 0% and 81.5%, respectively (p = 0.0003). At 5-years, the overall survival was 80% in patients who had adjuvant radiation compared to 21.4% in patients who did not have adjuvant radiation (p = 0.0026). Radiation therapy was the only studied variable that was associated with pelvic control. Radiation therapy, advanced age and pelvic lymphadenectomy were associated with overall survival.ConclusionsAdjuvant radiation therapy in patients with FIGO IB endometrial carcinoma with high risk histologies was associated with improved vaginal control, pelvic control, and overall survival.