National Trends and Impact of Regionalization of Radical Cystectomy on Survival Outcomes in Patients with Muscle Invasive Bladder Cancer.

Abstract

To evaluate national trends and the effect of surgical volume on perioperative mortality and overall survival (OS)in patients undergoing radical cystectomy (RC) for muscle invasive bladder cancer (MIBC). We investigated the National Cancer Database to identify patients with localized MIBC (cT2a-T4, M0) who underwent RC from 2004 to 2014. Demographics, 30- and 90-day mortality rates, as well as OS were analyzed. Hospitals were stratified into low-, medium-, and high-volume centers according to median number of RCs performed per year. Multivariate logistic regression models were fitted to identify independent predictors of perioperative mortality. Kaplan-Meier survival curves were generated to evaluate OS. Cox proportional hazard modeling was performed to identify independent predictors of OS. A total of 24,763 patients with localized MIBC who underwent RC from 2004 to 2014 were included in the study. Overall, most (70.85%) RCs occurred at low-volume hospitals, whereas only 15.83% were performed at high-volume hospitals. Thirty-day mortality rates were 2.87%, 2.19%, and 1.83% (P< .01); and 90-day mortality rates were 8.25%, 6.9%, and 5.9% (P< .01) at low-, medium-, and high-volume hospitals, respectively. Multivariate analyses identified RC volume as an independent predictor of 30- and 90-day mortality. RC in high-volume hospitals was associated with a 35% risk reduction in 30-day mortality (odds ratio 0.65, 95% confidence interval [CI] 0.49-0.85; P< .01), and a 26% risk reduction in 90-day mortality (0.74, 95% CI, 0.63-0.87; P< .01). Treatment at high-volume centers offers improved outcomes and OS benefit. However, in the United States, only 16% of RCs are performed in high-volume hospitals.