PD04-06 CYTOREDUCTIVE NEPHRECTOMY IN THE TARGETED THERAPY ERA: AN ANALYSIS OF THE NATIONAL CANCER DATA BASE

INTRODUCTION AND OBJECTIVES: The treatment of metastatic renal cell carcinoma (mRCC) has profoundly changed over the last decade. There is little comprehensive evidence evaluating the role of metastasectomy (MSx) in in this context. We assessed trends and predictors of MSx and their impact on overall survival in a large national cohort. METHODS: The National Cancer Data Base from 1998-2012 was queried to identify 25455 mRCC patients with 5315 undergoing MSx. Covariates included the application of targeted chemotherapy (CTX) and immunotherapy (ITX). Baseline descriptive and multivariable logistic regression analyzes for prediction of MSx were conducted. Trends for chemo(CTX) and immunotherapy (ITX) as well as MSx were assessed using the annual percent change linear regression technique (EAPC). Kaplan-Meier curves and adjusted Cox-proportional hazard models assessed the impact of MSx on overall survival. RESULTS: Compared to controls, MSx patients were significantly younger (p<0.001), had a lower CCI (p1⁄40.03), more often private insurance (p1⁄40.04) and a higher income (p<0.001). They were more often treated at an academic center (p<0.001), but less often received ITX/CTX (both p<0.001). The rates of MSx increased significantly over the years (9.9-24.5%, EAPC 4.52, p<0.001) while CTX (EAPC 3.08, p<0.001) increased and ITX decreased (EAPC -12.9, p<0.001). Diagnosis after 2006 (OR 1.21, 95%CI 1.02-1.23) and private insurance (OR 1.43, 95% CI 1.14-1.79) were positive predictors of MSx, whereas increasing age (OR 0.98, 95%CI 0.98-0.99), black race (OR 0.73, 95% CI 0.63-0.84), ITX (OR 0.8, 95%CI 0.68-0.94) and CTX (OR 0.75, 95% 0.69-0.82) were negatively associated with MSx. The combined treatment with MSx conferred a survival benefit compared to no MSx (HR 0.75, 95%CI 0.72-0.78) and CTX alone (HR 0.82, 95%CI 0.74-0.90). CONCLUSIONS: The addition of MSx to CTX conferred a survival benefit in our study despite lower usage of MSx after CTX. This suggests a potential underutilization, which might be a consequence of underlying health care access disparities as implied by lower odds of receiving MSx in blacks and higher odds in privately insured patients.