274 Background: Despite improvements in the medical management of advanced prostate cancer (aPC), it continues to be the 2nd leading cause of cancer death in American men. The contemporary management of men with aPC is increasingly complex and can vary based on access to up-to-date treatments, which is often found at busier treatment centers. We thus evaluated the relationship between facility volume and survival outcomes in aPC. Methods: The National Cancer Database (NCDB) was queried from 2004-2014 for aPC, defined as T4, N+, or M+ disease. Six pre-defined patient cohorts were evaluated. Cohort A = patients with aPC (N = 64,815); cohort B = M0 patients (N = 27,155); cohort C = M0 patients undergoing active treatment (N = 21,755); cohort = all M1 patients (N = 37,660); cohort E = M0 patients undergoing active treatment (N = 30,643); and cohort F = M1 patients who underwent active treatment and who had known metastatic sites (N = 12,452). Treatment facilities were divided into quartiles based on median treatment volume: <1.8 patients/year, 1.8-3.3 patients/year, 3.4-5.6 patients/year, and >5.6 patients/year. Regression models were adjusted along a set of covariates available in the NCDB. The primary outcome was overall survival (OS). Results: OS improved with each increase in volume quartile. The top quartile (>5.6 pts/yr) demonstrated significantly greater OS compared to the bottom quartile (<1.8 pts/yr) [HR 0.82, 95% CI 0.77-0.88, p<0.001]. The improved OS in the top volume quartile remained consistent when analyzed across the six pre-defined patient cohorts. Sensitivity analyses were conducted on Cohort A, adjusting for Gleason score and facility type, which did not change the effect of volume on survival. Conclusions: In this retrospective analysis of nearly 65K men who presented with aPC, we demonstrate that management at a high-volume facility (top quartile, >5.6 pts/yr) confers a significant OS advantage when compared to management at a facility in the lowest quartile (<1.8 pts/yr). This OS advantage persisted with similar magnitudes of effect after narrowing the cohorts by disease and treatment characteristics. These findings may have implications on the optimal management of men with advanced PC.
Contrasting genomic profiles in post-systemic treatment metastatic sites (MET) and pre-treatment primary tumors (PT) of clinically advanced prostate cancer (PC)
