African-American men with nonpalpable prostate cancer exhibit greater tumor volume than matched white men

Abstract

Background: Although prostate cancer (PC) mortality disproportionately affects African-American (AA) men, limited data exist comparing the pathologic characteristics of white and AA patients with nonpalpable PC (clinical stage T1c).

Methods: The authors reviewed the radical prostatectomy (RP) specimens from 37 consecutive AA men with clinical stage T1c PC and 35 white men who were matched for age, clinical stage, serum prostate-specific antigen (PSA) level, year of surgery, prostate weight, and prostate biopsy strategy. Pathologic characteristics were compared after mapping tumor foci and calculating tumor volumes by using computer software.

Results: For AA men, the median age (57.7 years), mean serum PSA level (9.3 ng/mL), mean prostate weight (43 g), and biopsy strategy (73% sextant) were matched with the cohort of 35 white men (median age, 57.1 years; mean PSA, 9.3 ng/mL;, mean prostate weight, 43 g; biopsy strategy, 66% sextant). Despite similar biopsy characteristics between the 2 groups (Gleason score > or =7 in 43% of AA men vs. 37% of white men), AA men exhibited significantly higher prostatectomy Gleason scores (> or =7 in 76% of AA men vs. 34% of white men; P = .01). AA men also had a higher mean tumor volume (1.82 cm3 vs. 0.72 cm3; P = .001) and had 2.8 times more tumor per ng/mL of serum PSA (0.22 cm3 per ng/mL vs. 0.079 cm3 per ng/mL; P = .001).

Conclusions: Compared with a cohort of white men with similar clinical features at the time of biopsy, AA men with nonpalpable PC had higher prostatectomy Gleason scores, greater cancer volume, and greater tumor volume per ng/mL of serum PSA. These data provide additional support for the concept of early PC detection using a serum PSA threshold of 2.5 ng/mL for biopsy among AA men.