Racial variation in prostate specific antigen in a large cohort of men without prostate cancer.
Several studies have reported racial variation in serum prostate specific antigen (PSA) levels. Many of these studies, however, have included a significant number of men without a documented digital rectal examination (DRE) result or without prostate biopsies if abnormalities in PSA or DRE were detected. Thus, it is not clear that men with prostate cancer have been excluded in these analyses. In this report, data from 9,162 men (3,786 African-American men and 5,376 white men) are reviewed. All men had both serum PSA and DRE testing. Every man in this study had either a documented normal DRE and PSA (< 4 ng/mL) (3,422 African-American men and 4,795 white men) or a negative prostate biopsy (364 African-American men and 581 white men). Data were analyzed in age-matched decades. African-American men and white men had no difference in serum PSA levels between 30 and 39 years of age. At 40-49, 50-59, 60-69 and 70-79 years of age, African-American men had a statistically higher serum PSA level than white men. From these data, we conclude that racial variation in serum PSA is present in all decades above 40 years of age. Our data are unique in that this cohort included a substantial number of men between 30 and 39 years of age. In this group of young men, no racial differences in serum PSA were detected. These studies indicate, for the first time, that the onset of racial variation in PSA occurs after the fourth decade of life.