To compare serum prostate-specific antigen (PSA) levels and PSA density (PSAD) among African American (AA), white, and Hispanic men with prostate cancer (PC) seen in an urban, equal-access urology clinic. Between January 1988 and January 1993, 1,105 men were screened for PC at Cook County Hospital in Chicago, Illinois. A total of 529 men underwent transrectal ultrasound-guided prostate gland biopsies for abnormal digital rectal examination, suspect transrectal ultrasound, elevated PSA, or any combination of these abnormalities. PC was found in 246 patients (204 AAs, 22 whites, and 20 Hispanics). We analyzed the differences in PSA and PSAD among the three racial groups using univariate and multivariate analyses adjusting for race, age, clinical stage, and grade. AAs have a higher mean serum PSA levels (21.56 ng/ml) than whites (mean PSA of 10.96 ng/ml) and Hispanics (mean PSA of 8.25 ng/ml) (p= 0.04). The mean PSAD also was higher in AAs than in the other two groups (0.68 versus 0.34 for whites and 0.31 for Hispanics, p= 0.05). On a multivariate analysis, the PC stage and grade were overwhelmingly significant, whereas the race and age lost their statistical significance. AAs have higher serum PSA and PSAD than whites or Hispanics in an equal-access healthcare environment. Race is a significant factor in determining PSA and PSAD on univariate but not on multivariate analysis. Preliminary studies suggest that these differences are due to sociological, not biologic causes. These findings warrant a large, prospective study to investigate the extent and the causes of the racial differences in PSA and PSAD.
From The University of Chicago/Michael Reese/University of Illinois Center for Radiation Oncology (I.A., S.V.); Department of Urology, Cook County Hospital (P.R.); Department of Pathology, Provident Hospital of Cook County (V.R.); and Department of Statistics, University of Chicago (F.V.), Chicago, Illinois, U.S.A.
Address correspondence and reprint requests to Dr. Srinivasan Vijayakumar, Department of Radiation Oncology, 2929 So. Ellis Ave., Room 149 MR, Chicago, IL 60616, U.S.A.