MP48-09 GRADE RECLASSIFICATION IN ACTIVE SURVEILLANCE FOR AFRICAN AMERICAN MEN WITH VERY LOW RISK PROSTATE CANCER

Abstract

INTRODUCTION AND OBJECTIVES: Previous studies have shown racial disparity in the epidemiology of prostate cancer (PCa) for African American (AA) men, creating a dilemma whether these men should be enrolled in active surveillance (AS). We sought to assess the risk of grade reclassification (GR) to grade group (GG) ≥2 and ≥3 in AA men, compared with a non-AA cohort, meeting the criteria for an indolent disease and otherwise ideal candidates for AS. METHODS: Between 1995-2018, we retrospectively identified 1,312 men with GG 1 (Gleason Score [GS] 6) cancer meeting the criteria for very low risk PCa (<3 cores positive, <50% maximum cancer involvement in any positive core and PSA density [PSAD] <0.15) at diagnosis, from the Johns Hopkins AS registry. Out of 1,312 men (median follow-up 4 years [IQR 2-7]), 103 men were AA while 1209 men were non- AA (97% Caucasian). Among AA men 22% had MRI targeted biopsies compared to 21% in non-AA men. Rates of GR to GG ≥2 (GS ≥3+4) and ≥3 (GS ≥4+3) were evaluated using survival analysis. RESULTS: The median number of biopsies was 3 (IQR 2-5) for both race groups and the median interval between biopsies was 45 months for AA men vs. 51 months for non-AA men (p=0.1). Thirty-one AA-men and 230 non-AA men had GR to GG ≥2. In men with GR, AA men were more likely to be upgraded to GG ≥3 compared to non-AA men (45% [14/31] vs 31% [72/230], p=0.03). On Kaplan-Meir analysis the 2, 5 and 10-year GR free survival in AA men vs. non-AA men was 84%, 69% and 50% vs. 90%, 81% and 70%, respectively for GR to GG ≥2 (p=0.002), and 92%, 83% and 78% vs. 97%, 94% and 91%, respectively for GR to GG ≥3 (p=0.001) (Figure). Upon adjusting for PSAD, age and year of diagnosis, AA men remained at a significantly higher risk of GR to GG ≥2 (HR=1.9, 95% CI [1.3-2.8]; p=0.001) and GG ≥3 (HR=2.6, 95% CI [1.4-4.7], p=0.002) as compared to non-AA men. CONCLUSIONS: African-American men meeting even the most stringent AS criteria have a relatively higher risk of harboring occult cancer foci of an aggressive phenotype compared to similar non- African-American men. Offering AS to these men should be approached with greater caution and, if enrolled, AA men should be closely followed. (Figure Presented).