DIAGNOSIS OF PROSTATE-CANCER - OPTIMAL NUMBER OF PROSTATE BIOPSIES RELATED TO SERUM PROSTATE-SPECIFIC ANTIGEN AND FINDINGS ON DIGITAL RECTAL EXAMINATION

The optimal number of core biopsies of the prostate that are needed fo r the detection of prostate cancer is unknown. A retrospective review of protocols and charts concerning 1149 transrectal ultrasound examina tions with biopsy performed in 1013 patients was undertaken. Cancer de tection rate was correlated to findings on digital rectal examination (DRE), serum levels of prostate-specific antigen (PSA) and number of b iopsies taken. The cancer detection rate was significantly higher in p atients who had five or more cores taken compared to those who had fou r or less (49% versus 35%, p < 0.05) in patients with serum PSA less t han 10 ng/ml and a DRE suspicious of malignancy. The same trend was se en in patients with normal DRE and PSA less than 10 ng/ml (14% versus 8%, p = 0.057), while the detection rate for prostate cancer was unaff ected by the number of cores taken if serum PSA was above 10 ng/ml.