Racial differences in tumor volume and prostate specific antigen among radical prostatectomy patients

Black men with and without prostate cancer in general have higher prostate specific antigen (PSA) before screening and treatment than other racial groups. A preliminary study suggested that higher PSA levels may be primarily due to greater tumor burden. We compared PSA and 3-dimensional (D) tumor volume in a consecutive cohort of black and white radical prostatectomy patients in an equal access military health care setting to determine racial differences in these parameters.

Prospective data collection, 2.25 mm. step section whole mount specimen processing and 3-D tumor volume assessment were performed in 226 patients with clinical stage T1-T3 prostate cancer undergoing radical prostatectomy at our center between April 1993 and March 1997. Of the patients 25 were excluded from further analysis because of neoadjuvant hormone treatment, T3 disease or Asian race. A total of 155 white and 46 black patients were compared.

There was no significant racial difference in the distribution of patients by age, clinical stage, pathological stage, Gleason sum or benign prostate gland volume. A significant racial difference was noted for pretreatment PSA and 3-D tumor volume. PSA values were higher in black men than in white men, and the racial difference remained statistically significant in multivariate analysis adjusting for 3-D tumor volume, benign gland volume, age, stage and Gleason sum.

Racial difference in PSA persists, despite rigorous covariate adjustment, and further study is needed to explain this PSA difference.