Outcomes in Black and White Patients With Metastatic Renal Cell Carcinoma Treated With First-Line Tyrosine Kinase Inhibitors: Insights From Two Large Cohorts

Abstract

PURPOSETo investigate whether black race is an independent predictor of overall survival (OS) in metastatic renal cell carcinoma (mRCC).METHODSWe performed a retrospective 2-cohort (International Metastatic Renal Cell Carcinoma Database Consortium [IMDC] and trial-database) study of patients with mRCC treated with first-line tyrosine kinase inhibitors (TKIs). Unmatched (UM) and matched (M) analyses accounting for imbalances in region, year of treatment, age, and sex between races were performed. Cox models adjusting for histology, number of metastatic sites, nephrectomy, and IMDC risk compared time to treatment failure (TTF; IMDC cohort), progression-free survival (PFS; trial-database cohort), and OS.RESULTSThe IMDC cohort included 73 black versus 3,381 (UM) and 1,236 (M) white patients. The trial-database cohort included 21 black versus 1,040 (UM) and 431 (M) white patients. Median OS for black versus white patients was 18.5 versus 25.8 months in the IMDC group and 21.0 versus 25.6 months in the trial-database group. Differences in OS were not significant in multivariable analysis in the IMDC group (hazard ratio [HR]M, 1.0; 95% CI, 0.7 to 1.5; HRUM, 1.1; 95% CI, 0.8 to 1.4) and trial-database (HRM, 1.5; 95% CI, 0.8 to 2.7; HRUM, 1.4; 95% CI, 0.8 to 2.6) cohorts. TTF for black patients was shorter in the UM IMDC cohort (HRUM, 1.4; 95% CI, 1.1 to 1.8; P = .003), but not in the M analysis. PFS was shorter for black patients in both analyses in the trial-database cohort (HRM, 2.3; 95% CI, 1.4 to 3.9; P = .002; HRUM, 2.3; 95% CI, 1.4 to 3.9; P = .002).CONCLUSIONBlack patients had more IMDC risk factors and worse outcomes with TKIs versus white patients. Race was not an independent predictor of OS. Strategies to understand biologic determinants of outcomes for minority patients are needed to optimize care.