Racial variation in the outcome of subsequent prostate biopsies in men with an initial diagnosis of atypical small acinar proliferation (ASAP).

Abstract

141 Background: African Americans (AA) are known to have more aggressive prostate cancer (PCa) and a greater probability of death from PCa. We sought to determine predictors of subsequent detection and risk stratification of PCa in a racially diverse group of men who presented with atypical small acinar proliferation (ASAP) on initial prostate biopsy. Methods: Upon receiving IRB approval, a retrospective analysis was performed on men from the Southeast Louisiana Veterans Health Care System and Tulane University Medical Center who presented with ASAP on initial prostate biopsy and subsequently received confirmatory prostate biopsies from September 2000 through July 2015. Confirmatory biopsy with a greater than 3-year interval from the initial were excluded. Self-identified race, age, body mass index (BMI), transrectal ultrasound (TRUS) volume, serum prostate-specific antigen (PSA), PSA velocity (PSAV), PSA density (PSAD), and elapsed time between biopsies were evaluated to determine if they were predictors of subsequent PCa diagnosis in patients with an initial finding of ASAP. Results: Of the 106 men in the analysis cohort, 75 (71%) were AA and 31 (29%) were not African American (non-AA). AA had higher PSA, PSAV, and PSAD (all p < 0.05). Age, BMI and TRUS volume were not statistically different between AA and non-AA. PCa was diagnosed in subsequent biopsy in 42 (40%) patients without significant racial variation; 30 (40%) AA vs 12 (39%) non-AA. Of the 42 men with PCa, 25 (24%) met Epstein pathological criteria for significant disease, although without racial variation; 18 (24%) AA vs 7 (23%) Non-AA. Only 10 (9%) men, again without racial variation, had any component of Gleason 4; 7 (9%) AA vs 3 (10%) non-AA. On multivariate analysis, increasing age, PSA and PSAD were significant predictors of cancer on repeat biopsy while race, BMI, TRUS volume and number of cores with ASAP were not. Conclusions: AA diagnosed with ASAP on initial prostate biopsy do not have increased risk of PCa on confirmatory biopsy compared to non-AA. Regardless of race, most cancers were low grade and lower volume, and AA with ASAP should be managed in a similar manner to non-AA with ASAP.