Disease-free survival after vaginal vault brachytherapy versus observation for patients with node-negative intermediate-risk endometrial adenocarcinoma

Purpose: To compare the disease-free survival (DFS) of patients with surgical stage 1, intermediate-risk endometrial adenocarcinoma (EAC) treated with primary surgery with or without adjuvant vaginal vault brachytherapy (VVBT). Patients and Methods: A retrospective chart review identified 575 patients with stage 1B, 1C or 2A endometrial cancer who had surgery between 1990 and 2004. All patients were surgically staged and 259 patients received postoperative VVBT. The date and site of first recurrence were considered the primary statistical endpoints and were analysed by univariate and multivariate Cox models. Subgroups of patients stratified by substage and grade were created and Log-rank tests using vaginal recurrence as the endpoint were calculated within these groups. Results: After a mean follow up period of 72 months (95%-confidence interval (CI): 68 to 75 months) a total of 43 (7.5%) patients developed recurrence. Multivariate analysis demonstrated that increasing patient's age at diagnosis and stage 1C or 2A disease were independent risk factors for recurrence whereas the grade of differentiation and the type of treatment (surgery alone vs. surgery followed by postoperative VVBT) were not associated with a change in DFS. Analysis within the subgroups stratified by substage and grade did not even reveal a trend towards improved local control with VVBT. Conclusion: Postoperative VVBT was not associated with a measurable reduction in the risk of recurrence in surgical stage 1, intermediate-risk endometrial cancer.