Obese African-Americans with prostate cancer (T1c and a prostate-specific antigen, PSA, level of <10 ng/mL) have higher-risk pathological features and a greater risk of PSA recurrence than non-African-Americans.

ABSTRACT

OBJECTIVE: to analyse the relationship between African American (AA) race and obesity in men with prostate cancer. PATIENTS AND METHODS: in all, 4196 patients who underwent radical prostatectomy from 1988 to 2008 were identified in the Duke Prostate Center database. A subset of 389 (AA 20.9% and non-AA 79.1%) patients with a body mass index (BMI) of ≥30 kg/m(2) , T1c disease and a prostate-specific antigen (PSA) level of <10 ng/mL were stratified by race and analysed. Age at surgery, race, surgical margin status, pathological tumour stage (pT2, pT3/4), pathological Gleason sum (<7, 3 + 4, 4 + 3, >7), extracapsular extension (ECE), seminal vesicle invasion and tumour percentage were assessed by univariate analysis followed by Cox regression analysis. RESULTS: in the entire cohort, 143 (38.1%) AA men were obese, compared to 509 (25.0%) of the non-AA men. AA men had a significantly higher tumour percentage (15% vs 10%, P= 0.002), and a greater proportion of pT3/4 disease (45.1% vs 26.2%, P= 0.039), pathological Gleason sum ≥ 7 (70.7% vs 50.5%, P= 0.003), positive ECE (37.8% vs 23.1%, P= 0.007), and positive surgical margin (52.4% vs 36.8%, P= 0.010) than non-AA men. AA men had a greater risk of PSA recurrence on Kaplan Meier (P= 0.004) and Cox regression analysis (P= 0.040, hazard ratio 1.72) CONCLUSION: a greater proportion of AA men was obese in this cohort. Obese AA with impalpable cancer and a PSA level of <10 ng/mL have a higher risk of pathological features than obese non-AA men, as well as a higher risk of PSA recurrence. Obesity might be responsible for the racial disparity seen in prostate cancer.