Prospective study of cancer detection in black and white men with normal digital rectal examination but prostate specific antigen equal or greater than 4.0 ng/mL

Abstract

Background: The serum prostate specific antigen (PSA) concentration with no clinical evidence of prostate carcinoma is higher and more variable in black than in white American men. The influence of this phenomenon on relations between race, PSA, and cancer detection in men with a PSA greater than or equal to 4.0 ng/mL has not been investigated.

Methods: Between January 1992 and December 2000, 451 black and 480 white men with a normal digital rectal examination and a PSA greater than or equal to 4.0 ng/mL had an initial prostate biopsy at one medical center. The histology of the biopsy specimens and the Gleason score of malignant specimens was determined by one uropathologist.

Results: Cancer was detected in 207 (46%) black and 167 (35%) white men (P = 0.0006). When adjusted for PSA, cancer detection was also greater in the black than the white men, but the difference did not achieve statistical significance (relative risk, 1.30; 95% confidence interval [CI], 0.99-1.71; P = 0.06). Gleason score 7-10 cancer was detected in 88 (20%) black and 45 (9%) white men (P = 0.0001), and the difference remained significant when adjusted for PSA (relative risk, 1.73; 95% CI, 1.16-2.61; P = 0.0008). In the intermediate PSA range of 4.0-9.9 ng/mL, cancer detection and Gleason score 7-10 cancer detection was greater in black than in white men younger than 60, 60-69, and 70 years of age or older, but the difference was significant only for Gleason score 7-10 cancer detection among men 60-69 years of age (P = 0.006).

Conclusions: There is a direct correlation between Gleason score and cause specific survival with local stage prostate carcinoma. The authors' study indicates that prostate carcinomas with established malignant potential are more likely to be identified in black than in white men with PSA elevation as the only indication of malignancy and raises the possibility that a PSA threshold less than 4.0 ng/mL in black men younger than 70 years of age may reduce racial disparities in prostate carcinoma morbidity and mortality.