The role of post-cystectomy radiation in treatment of squamous cell carcinoma of the bladder: A combined retrospective analysis.

Abstract

259 Background: Squamous cell carcinoma (SCC) is the most common nonurothelial histology in bladder cancers. Given the high locoregional recurrence as the primary cause of death, radiation therapy (RT) is often recommended in the post-operative setting. Large-scale randomized trials that are dedicated to bladder SCC would be difficult to accrue to adequate numbers. Therefore, we utilized the Surveillance, Epidemiology, and End Results (SEER) database. Methods: The SEER (1998-2007) was queried for patients with muscle-invasive (stage II-IV) squamous cell carcinoma of the urinary bladder who underwent complete cystectomy. Kaplan-Meier survival analysis and Cox regressions were used to assess survival outcomes. Additionally, records were reviewed for patients treated at New York Presbyterian Hospital-Weill Cornell Medical College (NYP-WCMC) between 1991 and 2010. Results: A total of 331 patients from the SEER were included in the analysis; Majority were received cystectomy alone (n=297), while 10% (n=34) received post-operative RT. Factors associated with post-operative RT were younger age (p=0.03) and more advanced stage at diagnosis (p<0.001). Median survival was 40 months for patients treated with surgery alone and 18 months for post-operative RT (p<0.05). In the institutional record review, 17 patients underwent cystectomy; of these, 5 received post-cystectomy RT. Those who underwent post-operative RT had better performance status (80% vs 25%) and a higher rate of positive surgical margins (67% vs 20%). Median survival was 38 months for patients treated with surgery alone and 22 months for post-op RT. Conclusions: RT has been employed as a post-operative treatment for some patients with muscle-invasive SCC of the urinary bladder. Younger age, better performance status, advanced stage, and positive margins may prompt the use of post-operative RT. However, both SEER and single institution retrospective analyses failed to show any survival advantage associated with the use of post-operative therapy. Further studies are needed to identify any subsets of patients with bladder SCC who may benefit from post-cystectomy radiation.