The Clinical Significance of Transrectal Ultrasonography, Prostate-specific Antigen and Prostate-specific Antigen Density for the Reduction of Unnecessary Biopsies

Kim, Hyun Tae; Song, Phil Hyun; Moon, Ki Hak

Abstract

PURPOSE: To establish criteria for the safe reduction of unnecessary biopsies, we compared transrectal ultrasonography (TRUS) findings, serum prostate-specific antigen (PSA), and PSA density (PSAD) in the decision criteria for the TRUS guided prostate biopsy (TRUS-Bx). MATERIALS & METHODS: A total of 914 patients underwent TRUS-Bx due to elevated PSA and/or focal nodules on the TRUS. The patients were divided into the prostate cancer (n=286, 31.3%) and the non-prostate cancer groups (n=628, 68.7%). The sensitivity, specificity, and accuracy of TRUS, PSA, and PSAD were retrospectively evaluated, and the single criterion or the combinations of the criteria which can safely reduce the unnecessary biopsies without missing prostate cancer were investigated.
RESULTS
The sensitivity, specificity and accuracy of TRUS, PSA (cut-off value, 4ng/ml) and PSAD (cut-off level, 0.20ng/ml/cc) were 75.9%/78.3%/53.8%, 33.0%/52.5%/73.7%, and 34.0%/42.9%/48.3%, respectively. At the cut-off level of PSAD (0.20 ng/ml/cc), 65.1% of unnecessary biopsies were spared but 132 cases (22.2%) of prostate cancer were detected. However a focal nodule was detected on TRUS in 120 cases (90.9%) and the remaining 12 cases (9.1%) had PSA above 10ng/ml. By the combinations of criteria (PSAD, TRUS and PSA), 27.7% of unnecessary biopsies were spared without missing cancer.
CONCLUSIONS
A short-interval follow-up seems to substitute for the prostate biopsy if PSAD is below 0.20ng/ml/cc without nodular lesions on TRUS and PSA value is below 10ng/ml.