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

Objective: 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).

Methods: 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.

Results: 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).

Conclusions: 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.