Predictors of post-surgical race-specific prostate cancer progression.

Abstract

5048 Background: Disparity in prostate cancer (CaP) incidence and mortality for African American (AA) versus Caucasian American (CA) men may reflect tumor biology, comorbidity, treatment, follow-up care, and/or health care access. In a racially diverse cohort of patients undergoing radical prostatectomy (RP), this study examined how race, comorbidity, and PSA doubling time (PSADT) impact CaP progression. Methods: Enrollees in the Center for Prostate Disease Research (CPDR) Multi-Center National Database from 1989-2014 who underwent RP within 12 months of CaP diagnosis were eligible. Biochemical recurrence (BCR) was defined as PSA ≥0.2 ng/mL post-RP. Comorbid conditions included coronary artery disease (CAD), cerebral vascular incident (CVI), Type II diabetes (DB), hypertension (HT), elevated cholesterol (EC), lung disease (COPD), prostatitis (PS), renal insufficiency (RI) and other cancer (OC). Multivariable Cox proportional hazards (PH) analysis was used to examine comorbid conditions (yes vs. no) and PSADT ( < 3, 3-8.9, 9-14.9, and ≥15 mos) to predict BCR, controlling for age at RP, D’Amico risk stratum, pathology features, and adjuvant treatment. Results: A total of 6,785 patients were eligible; 22% AA and 78% CA. Median age and follow-up was 62 and 6.1 years, respectively. Across race, comparable median follow-up time, distributions of pathologic features and adjuvant treatments were observed. However, AA vs. CA patients had greater HT (53 vs. 39% p < 0.0001), DB (17 vs. 7%, p < 0.0001), and RI (3 vs. 1%, p = 0.002). Alternatively, CA vs. AA patients had greater CVD (10 vs. 7%, p = 0.0008) and OC (3 vs. 0.5%, p < 0.0001). Cox PH analysis showed poorer BCR-free survival for AA vs. CA men (HR = 1.28, CI = 1.11, 1.48, p = 0.0009) adjusting for D’Amico risk stratum, pathology, and treatment. PSADT, not comorbidity, was a critical predictor of BCR, with poorest outcome at extremes: HR PSADT < 3 vs. > = 15 months = 41.5, CI = 33.6, 51.3, p < 0.0001). Conclusions: Despite comparable health care access and distribution in clinical risk stratum and pathology features, race persisted in predicting poor CaP outcome. Disparate comorbidity for AA and CA men did not eliminate this difference. PSADT remained the most striking determinant of poor BCR-free survival.