Defining a "High Volume" Radical Cystectomy Hospital: Where Do We Draw the Line?

Background: Centralization of radical cystectomy (RC) to "high volume" centers can lead to decreased morbidity but also limits access to care. In the context of centralization, there is a need to systematically define the hospital volume cutoffs for this procedure.
Objective: To systematically examine the effect of hospital volume on inpatient complications of RC for bladder cancer and to define a threshold to minimize RC morbidity.
Design, Setting, and Participants: This was a retrospective analysis of data for 6790 adults undergoing RC for nonmetastatic bladder cancer during 2008-2011 from the National Inpatient Sample (weighted population estimate of 33 249 RCs in the USA during this period).
Intervention: RC.
Outcome Measurements and Statistical Analysis: Overall and major complications were defined according to International Classification of Diseases (9th revision) diagnosis and procedure codes. To define the relationship between hospital volume and morbidity, logistic regression analyses within a generalized estimating equation framework with restricted cubic splines were used.
Results and Limitations: The inpatient complication rate was 4769/6790 (70.2%), of which 1572/6790 (23.2%) were major complications. Restricted cubic spline analysis revealed a significant inverse nonlinear association between hospital volume and complications. The odds of complications decreased with increasing volume, with a plateau at 50-55 cases/yr for any complications (p=0.024) and 45-50 cases/yr for major complications (p=0.007).
Conclusions: The relationship between hospital volume and RC morbidity is nonlinear, with a plateau for the complication rate at 50-55 cases/yr. Restricting RC to centers with such high thresholds will restrict access to care. There is a need to identify and publish best practices from high-volume centers in quality improvement initiatives to improve morbidity at low-volume centers.
Patient Summary: There is a nonlinear relationship between the annual number of radical cystectomy procedures performed at a hospital and the inpatient complication rate. Complications decrease with increasing hospital volume and reach a plateau at 50-55 cases per year, beyond which the incremental benefit of increasing volume is minimal.
(Copyright © 2019 European Association of Urology. Published by Elsevier B.V. All rights reserved.)