The significance of repeat prostate biopsy for the detection of prostate cancer

Purpose: To evaluate the results of serial prostate biopsy in men with elevated prostate-specific antigen (PSA) levels, where the initial biopsies were negative for cancer. Materials and methods: Between January 2000 and December 2003, 750 men with a serum PSA level of 4.0ng/ml or greater underwent transrectal ultrasound guided needle biopsy of the prostate, with 218 (29.1%) diagnosed as having prostate cancer. Of the other 532 men, 104 (19.5%), whose follow-up PSA level was persistently elevated beyond the normal range, underwent a second biopsy, with 26 (4.9%) undergoing third and subsequent biopsies for the same reason. The cancer detection rates after each biopsy session, and reliable predictors for prostate cancer after the 2nd biopsy in those whose PSA level was in the gray zone, were evaluated. Results: The cancer detection rates of the 1st, 2nd and 3rd biopsies were 29.1, 16.3 and 30.7%, respectively, with 10.3% of the prostate cancers detected in this study missed on the initial biopsy. The detection rate of the second biopsy in gray zone patients was 13.1%, which was comparable to the first biopsy result (12.7%) for the same range group. The median PSA, % free PSA and PSA density were significantly different between the prostate cancer and non-cancer groups after the second biopsy in gray zone patients (p < 0.05). Conclusions: 10.3% of the prostate cancers detected in this study were missed on the initial biopsy. The median PSA, % free PSA and PSA density are reliable predictors of prostate cancer after the second biopsy in gray zone patients.