Clinical outcomes of adjuvant chemotherapy and vaginal brachytherapy with or without pelvic radiation for surgical stage I-II uterine serous carcinoma.

Objective(s): To evaluate the benefit of adding pelvic radiation treatment (EBRT) to vaginal cuff brachytherapy (VB) for women with early stage uterine serous carcinoma (USC) treated with adjuvant chemotherapy.

Materials And Methods: After institutional review board (IRB) approval, the authors retrospectively identified 56 patients with 2009 International Federation of Gynecology and Obstetrics (FIGO) Stage I-II USC treated with hysterectomy, bilateral oophorectomy +/- lymphadenectomy, adjuvant chemotherapy, and radiation therapy with either VB alone (n = 33) or VB + EBRT (n = 23) between July 1998 and August 2009.

Results: Median age and follow-up were 68.5 years and 54 months respectively. Median VB alone surface dose was 37.5 Gy and median pelvic EBRT dose was 45 Gy. The prevalence of lower uterine segment involvement, > 50% myometrial invasion, and Stage II disease were higher for patients receiving VB + EBRT. Overall, only one vaginal recurrence was observed. Pelvic recurrence rate was 26% for VB + EBRT compared to 12% for VB alone (p = 0.179). The five-year recurrence-free survival (RFS) was 80.5% for VB vs 67.3% for VB + EBRT (p = 0.3847), and the five-year overall survival (OS) was 65.9% for VB vs 66.7% for VB + EBRT (p = 0.7159). On univariate and multivariate analysis, radiation treatment modality was not a predictor for local control or survival.

Conclusions: In this cohort, there was no significant clinical benefit of adding pelvic EBRT to the adjuvant management of early stage uterine serous carcinoma. The higher prevalence of high-risk features in the VB + EBRT group may underestimate the value of this treatment. Further investigation is warranted to identify the optimal radiation treatment regiment for early stage USC treated with surgery and adjuvant chemotherapy.