The Impact of Hospital Volume on Short-term and Long-term Outcomes for Patients Undergoing Radical Nephroureterectomy for Upper Tract Urothelial Carcinoma

Abstract

To examine the effect of hospital volume on short and long-term outcomes for radical nephroureterectomy (RNUx). Upper tract urothelial carcinoma is a rare malignancy that few surgeons have experience with. The hospital volume-outcome relationship has been well established for other cancers but not RNUx. The National Cancer Database was queried for all cases of upper tract urothelial carcinoma that underwent RNUx from 2004 to 2016. Average annual hospital volume for radical nephroureterectomy was stratified into tertiles. The upper tertile, defined as 6 or more RNUx per year, was considered high volume while low volume was less than 6 RNUx per year. Kaplan-Meier and Cox proportional hazards regression were used to identify independent predictors of overall survival, and logistic regression was used to identify predictors of perioperative outcomes. We identified 37,479 RNUx performed across 1290 hospitals. There were no differences in baseline health or cancer staging between patients who presented at low- versus high-volume centers. Both peri-operative survival (30- and 90-day mortality) and long-term overall survival were improved in patients treated at high-volume centers. On multivariable survival analysis, treatment at a high-volume center was associated with improved hazards of survival. This relationship for long-term survival remained consistent on landmark analysis where patients who died within 90 days of surgery were removed. Treatment at a high-volume hospital was associated not only with improved short-term perioperative outcomes but also with improved overall long-term survival. The mechanism behind this is likely multifactorial with surgeon volume, and ancillary support services all playing critical roles.