Optimizing the Role of Surgery and Radiation Therapy in Urethral Cancer Based on Histology and Disease Extent.

Abstract

Urethral cancer is rare, with limited data guiding treatment. A national hospital-based registry was used to evaluate the role of local therapy in these patients. We performed a retrospective cohort study of patients who, between 2004 and 20013, received a diagnosis of T0-4N0-2 M0 urethral cancer. Local therapy was radiation therapy (RT), surgery (S), or S and RT (S+RT). The Cox proportional hazards model was used to assess the impact of therapy type on overall survival (primary endpoint). Subgroup analysis by extent of disease (early stage [T0-2 N0] vs locally advanced [T3+ or N+]) and histology was performed. In our study, 2614 patients had a median follow-up of 28 months. Three-year overall survival was 54%. In 501 patients with locally advanced disease, S+RT was associated with improved survival versus S alone (hazard ratio [HR] 0.58; 95% confidence interval [CI], 0.42-0.80). There was no difference for patients with squamous cell carcinoma by treatment type, but patients with adenocarcinoma (RT vs S: HR 0.20; 95% CI, 0.07-0.60) or transitional cell carcinoma (S+RT vs S: HR 0.45, 95% CI, 0.26-0.77) had improved OS with RT as part of treatment. In 1705 early-stage patients, there was no association with survival when comparing S+RT versus S. For patients with locally advanced disease and transitional cell carcinoma undergoing S, the addition of RT is associated with improved overall survival and should be considered. An RT-based approach may be preferred for adenocarcinoma, but there was no clear association with survival by therapy type for squamous cell carcinoma. This study is hypothesis generating; prospective trials are necessary.