Predictive factors of recurrence following adjuvant vaginal cuff brachytherapy alone for stage I endometrial cancer.

PURPOSE: The purpose of this study is to identify risk factors for recurrence in a cohort of stage I endometrial cancer patients treated with vaginal cuff brachytherapy at a single academic institution.

METHODS AND MATERIALS: From 1989 to 2011, 424 patients with stage I endometrial cancer underwent total hysterectomy and bilateral salpingo-oophorectomy, with or without lymphadenectomy (LND), followed by high-dose-rate vaginal cuff brachytherapy (VCB) to patients felt to be high or intermediate risk FIGO stage IA and IB disease. Covariates included: 2009 FIGO stage, age, grade, histology, presence of lymphovascular space invasion, LND, and receipt of chemotherapy.

RESULTS: With a median follow-up of 3.7years, the 5 and 10-year disease free survival were 98.4% and 95.9%, respectively. A total of 30 patients developed recurrence, with the predominant pattern of isolated distant recurrence (57.0%). On multivariate analysis, grade 3 (p=0.039) and LND (p=0.048) independently predicted of increased recurrence risk. χ(2) analysis suggested that higher-risk patients were selected for LND, with significant differences in age, stage, and grade noted between cohorts. Distant metastatic rate was significantly higher for patients who qualified for GOG 0249 at 23.1% (95% CI 10.7-35.5%) compared to those who did not at 6.8% (95% CI 1.8-11.8%, p<0.001).

CONCLUSION: Overall disease-free survival for this cohort of patients was >95% at 10years. Univariate analysis confirmed previously identified risk factors as predictors for recurrence. Multivariate analysis found that grade 3 and LND correlated with risk for recurrence. Of those that did recur, the initial site of relapse included distant metastasis in most cases.