Predictors of Gleason score upgrading in a large African-American population

Abstract

Gleason score from biopsy specimens is important for prostate cancer (PCa) risk stratification and influences treatment decisions. Gleason score upgrading (GSU) between biopsy and surgical pathology specimens has been reported as high as 50 % and presents a challenge in counseling low-risk patients. While recent studies have investigated predictors of GSU, populations in these studies have been largely Caucasian. We report our analysis of predictors of GSU in a large urban African-American population. A total of 959 patients with D'Amico low-risk prostate cancer underwent radical prostatectomy at Georgetown University or Washington Hospital Center between January 2005 and July 2012. Race, age, PSA, body mass index (BMI), cancer of the prostate risk assessment (CAPRA) score, and transrectal ultrasound (TRUS) biopsy characteristics (percent of biopsy cores showing adenocarcinoma, highest percent of biopsy core involved with cancer, and measured TRUS prostate volume) were analyzed with both univariate and multivariate analyses to identify significant predictors of GSU while controlling for clinical parameters. Of the 959 cases, 288 (30.0 %) were upgraded on final pathologic specimen with approximately 38 % (133/355) of African-American patients experiencing GSU. BMI (P = 0.02), percent positive biopsy cores (P < 0.01) and percent of core involved with cancer (P < 0.01), increasing CAPRA score, and serum PSA were independent predictors of GSU on both uni- and multivariate regression analyses. African Americans had a 73 % increase in the incidence of GSU over other races. More than a quarter of low-risk prostate cancer patients were upgraded on final pathology in our series. Higher BMI, serum PSA, CAPRA score, percent of cores positive, and percent of cores involved were independent predictors of GSU. Individuals with those clinical parameters may harbor occult high-grade disease and should be carefully counseled on treatment decisions.