Primary Vaginal Cancer and Chemoradiotherapy A Patterns-of-Care Analysis

Introduction: No prospective randomized trials exist to delineate the role of combined chemoradiotherapy (CRT) in the treatment of vaginal cancer (VC). We sought to describe the utilization rate of CRT and evaluate the potential survival benefit of CRT over radiotherapy alone in VC. Methods: A retrospective analysis of the SEER-Medicare-linked database was performed analyzing women with VC treated with external beam radiation and/or brachytherapy and diagnosed between 1991 and 2005. Results: Of the 1709 primary VC patients in the SEER-Medicare database, 326 met inclusion criteria. Most were white (80.1%) and in the 70- to 74-year age group (42.1%). Squamous cell carcinoma was the most predominant histologic diagnosis (80.4%). Brachytherapy was used in 34% of patients, whereas cisplatin was the chemotherapy of choice in 59% of CRT patients. Median follow-up was 21.5 months. Kaplan-Meier estimated that 5-year cause-specific survival (CSS) and overall survival (OS) was 67.6% and 27.1%, respectively. Before 1999, CRT was used in 7.5% of patients compared with 36.1% of patients thereafter (P < 0.001). Chemoradiotherapy was less likely to be used in patients older than 80 years (P < 0.001) but was otherwise balanced in race, stage, grade, histologic diagnosis, comorbidities, and brachytherapy use. Chemoradiotherapy did not correlate with CSS (hazard ratio [HR], 0.91; P = 0.84) or OS (HR, 1.34; P = 0.21) by multivariate analysis. Factors associated with worse CSS include stage IVA disease (HR, 4.2; P = 0.003) and 2 or more comorbidities (HR, 2.89; P = 0.03). Factors associated with worse OS include age older than 80 years (HR, 1.78; P = 0.04), stage IVA disease (HR, 3.35; P < 0.0001), and 2 or more comorbidities (HR, 2.58; P = 0.001). Conclusions: Chemoradiotherapy utilization for VC has increased since 1999. We failed to delineate a CSS or OS benefit for CRT in this cohort.