Predictors of surgical quality for retroperitoneal sarcoma: Volume matters

Background and Objectives: The volume-outcome relationship is well recognized. We sought to investigate this relationship in retroperitoneal sarcoma (RPS) surgery. Methods: Non-metastatic RPS cases from 2004 to 2014 in the National Cancer Database were analyzed. Hospitals in the top 10th percentile for volume were defined as high-volume. Outcomes were selected a priori based on their known prognostic significance, including surgery use, R0/R1 resection, and R0 resection. Volume-outcome associations were assessed by univariate and multivariable analyses. Results: Of 3141 RPS cases identified, 70.0% were managed surgically. Of these, 93.0% were R0/R1 resections, and 67.6% were R0 resections. Surgical management, R0/R1 resection, and R0 resection were each associated with improved overall survival (P < 0.001). Hospital volume was an independent predictor of surgical management, R0 resection, and R0/R1 resection. Patients treated at high-volume centers had 1.9-fold higher odds of undergoing surgical management (P < 0.001), 2.5-fold higher odds of receiving a R0/R1 resection (P = 0.026), and 1.8-fold higher odds of an R0 resection (P < 0.001). Academic setting predicted use of surgical management (P < 0.001) and R0/R1 resection (P = 0.015) but not R0 resection (P = 0.882). Conclusions: High-volume hospitals are significantly associated with surgery use and improved surgical outcomes. Consideration should be given to further centralization of RPS care.