Impact of Hospital Case Volume on Outcomes Following Radical Nephrectomy and Inferior Vena Cava Thrombectomy

Abstract

BackgroundRadical nephrectomy with inferior vena cava thrombectomy (RN-IVCT) is a complicated procedure for which the impact of hospital case volume on overall survival (OS) is unknown. ObjectiveTo assess the degree to which renal cell carcinoma (RCC) with inferior vena cava tumor thrombus (IVC-TT) care is centralized and to evaluate the impact of hospital case volume on outcomes following RN-IVCT. Design, setting, and participantsThe National Cancer Data Base was queried for patients with pT3b–c RCC treated with RN-IVCT. Hospitals were classified by case volume percentile as low (<75th percentile, <0.67 cases annually), intermediate (75th–95th percentile, 0.67–2.99 cases annually), or high (>95th percentile, >3 cases annually). Outcome measurements and statistical analysisThe primary outcome was OS. Secondary outcomes were short-term (30- and 90-d) mortality rates according to hospital case volume. Kaplan-Meier curves and Cox regression model were used to evaluate OS and the effect of covariables. Results and limitationsThere were 2664 cases of RN-IVCT for pT3b–c tumors reported by 573 institutions, of which 435, 108, and 30 were classified as low, intermediate, and high volume, accounting for 28.5%, 34.5%, and 37% of cases, respectively. Treatment at high-volume institutions was associated with better OS: the median OS was 42, 53, and 60 months for low, intermediate and high-volume centers, respectively (p=0.009). After multivariable adjustment, treatment at a high-volume institution was associated with a 24% relative risk reduction for all-cause mortality compared to treatment at a low-volume institution (hazard ratio 0.76, 95% confidence interval 0.65–0.89; p=0.001). There was no significant difference in short-term mortality following RN-IVCT when stratified by hospital case volume. ConclusionsHigher hospital case volume was associated with longer OS for patients undergoing RN-IVCT. These findings support efforts to centralize care for cases of advanced RCC. Patient summaryIn this study we looked at the impact of hospital case volume on survival following surgery for renal cell carcinoma and inferior vena cava thrombectomy. Survival was significantly better in high-volume hospitals performing three or more procedures per year.