Active Surveillance for Low-Risk Prostate Cancer in Black Patients: A United States Population-Based Analysis

Abstract

Purpose: Evidence from clinical trials supports conservative management with Active Surveillance/Watchful Waiting (AS/WW) as an acceptable alternative to definitive therapy for low-risk prostate cancer (LRPC). However, given concern for underlying aggressive disease and the underrepresentation of Black men in AS/WW clinical trials, expert panels currently advise caution with AS/WW in Black men. We therefore sought to characterize recent trends in AS/WW use across race. Methods: The novel Surveillance, Epidemiology, and End Results (SEER) Program Prostate with AS/WW Database queried 50,302 men with LRPC (clinical T1c-T2a, prostate-specific antigen [PSA] <10 ng/mL, Gleason 6) and known management type, diagnosed from 2010-2015 in the United States (N=5218 Black). Trends in AS/WW use over time were determined, stratified by race (Black versus non-Black). The Cochran-Armitage test evaluated trends in initial management over time. Multivariable logistic regression defined adjusted odds ratios (aOR) and 95% confidence intervals (CI) for receipt of AS/WW (versus definitive RP or RT), with race as the primary independent variable of interest. The validated Yost-index adjusted for socioeconomic status (SES). Results: From 2010 to 2015, AS/WW use increased from 12.6% to 36.4% (+23.8%) among Black men and from 14.8% to 43.3% (+28.5%) among non-Black men (Ptrends<0.001), with the absolute difference in rates across race increasing from 2.2% to 6.9%. Black men had lower odds of receiving AS/WW compared to non-Black men before adjusting for SES and insurance status (aOR 0.93 [95% CI, 0.88–0.99], P=0.02), but not after adjustment (aOR 1.01 [95% CI, 0.95–1.07], P=0.86). The aOR of AS/WW for Black versus non-Black men (ref.) went from 1.06 (95% CI, 0.89-1.25, P=0.52) in 2010 to 0.84 (95% CI, 0.73-0.98, P=0.02) in 2015 (PTrend=0.02), even after full multivariable adjustment. Conclusions: Using a population-based cohort containing the largest number of Black LRPC patients to-date to have quality-assured data on AS/WW in the United States, this report demonstrates that AS/WW use nearly tripled for both Black and non-Black men from 2010-2015, but that Black men were still managed with less AS/WW overall. This treatment disparity seemed to be largely accounted for by racial differences in SES and insurance status; nonetheless, differences in AS/WW use still widened over time and Black race appears to have emerged as an independent predictor of definitive treatment over AS/WW. There is currently no Level I evidence to support these trends, and future randomized trials will be needed to examine the safety and efficacy of AS/WW in Black men.