External radiotherapy versus vaginal brachytherapy for patients with intermediate risk endometrial cancer

Purpose: To determine if brachytherapy alone is adequate adjuvant local therapy in patients classified as intermediate risk after complete surgical staging for endometrioid adenocarcinoma. Methods: Between 1991 and 2004, 78 patients with FIGO stage IA-II (occult) disease meeting the eligibility criteria of GOG 99 received adjuvant radiotherapy following complete surgical staging (total abdominal hysterectomy and bilateral salpingo-oophorectomy, peritoneal cytology, and pelvic ± para-aortic lymphadenectomy) for endometrioid adenocarcinoma at Washington University in St. Louis. Forty-two patients received postoperative vaginal brachytherapy alone and 36 received postoperative pelvis external radiotherapy (XRT) and vaginal brachytherapy. Fifty-two patients were classified as having high intermediate risk disease and 26 patients had low intermediate risk disease as defined by GOG 99. Median follow-up for all patients was 55 months. Results: The 5-year overall and disease-free survivals for all patients were 86% and 89%, respectively. There was no difference in 5-year disease-free survivals among patients classified as high intermediate risk vs. low intermediate risk (p = 0.26) or in terms of radiation treatment received (p = 0.95). There were two patients that had > grade 2 gastrointestinal complications, both were treated with external radiotherapy and vaginal brachytherapy. Conclusions: Vaginal brachytherapy alone results in minimal morbidity and is adequate local therapy for intermediate risk patients with endometrioid adenocarcinoma after complete surgical staging.