Urachal versus nonurachal adenocarcinomas of the bladder: A population-based report.

Abstract

450 Background: Previous studies are inconclusive on whether urachal vs. non-urachal adenocarcinomas of the urinary bladder have different prognoses. Our objective was to assess survival differences between urachal vs. non-urachal adenocarcinomas in light of evolving treatment strategies over the past years. Methods: The Surveillance, Epidemiology, and End Results (SEER) database was used to identify patients with a diagnosis of adenocarcinoma of the urinary bladder between years 1988 and 2012. The variable of interest was urachal vs. non-urachal adenocarcinomas. Kaplan-Meier curves and log-rank tests were performed to assess the univariable effect of urachal vs. non-urachal adenocarcinomas on survival. Multivariable Cox regression analyses were performed for prediction of cancer-specific mortality (CSM) and overall mortality. Sub-analyses comprised of competing-risks regression models. Results: Overall, 2345 (89%) and 301 (11%) non-urachal and urachal adenocarcinoma patients were identified, respectively. The 5-year CSM-free survival rates for urachal vs. non-urachal adenocarcinomas were 63% vs. 50% (P< 0.001). For the same groups, the 5-year overall survival rates were 50% vs. 32%, respectively (P< 0.001). In multivariable Cox regression analyses, no difference was recorded between urachal vs. non-urachal adenocarcinomas for CSM (hazard ratio [HR]: 0.86, P= 0.2) or any mortality (HR: 0.84, P= 0.07). Important prognosticators of CSM and survival were surgery, lymph node dissection, disease stage and grade. Conclusions: No survival difference was recorded in the current study between urachal vs. non-urachal adenocarcinoma of the bladder. However, surgery and lymph node dissection constitute important factors for both tumor types.