Simple Risk Stratification to Detect Prostate Cancer with High Gleason Score in Repeat Biopsies in a Population Screening Follow-up Study

Abstract

Background: To investigate the clinical usefulness of percentage free prostate-specific antigen (%fPSA) and PSA velocity (PSAV) for detecting prostate cancer in repeat biopsies in a population-based screening cohort.

Patients and methods: In total, 178 men with serum PSA levels within 2.1-10 ng/ml who underwent repeat biopsies after initial negative biopsy results, were enrolled. Prostate cancer detection rates with a Gleason score of 7 or more according to age, serum PSA, %fPSA, and PSAV were investigated. The cumulative probability of detecting cancer according to risk factors was also investigated.

Results: Out of 178 men who underwent repeat biopsy, 48 (27.0%) were diagnosed with prostate cancer during the observation period, and pathological examination revealed prostate cancer with a Gleason score of 7 or more in 17 patients (35.4%). In the multivariate logistic regression analysis, %fPSA ≤ 12 at repeat biopsy and PSAV >0.40 ng/ml/year were determined to be independent risk factors for prostate cancer, and %fPSA ≤ 12 at initial biopsy and PSAV >0.40 for cancer of Gleason score 7 or greater. The cumulative probabilities of developing high-grade cancer after 5 years were 55.8% and 4.0% in men with %fPSA ≤ 12 at initial biopsy and PSAV >0.40, and in men without both, respectively. There was a statistically significant difference in probabilities between groups by the log-rank test.

Conclusion: The present results demonstrated that %fPSA and PSAV were predictors of prostate cancer with a Gleason score of 7 or more in repeat biopsy after a negative initial biopsy on a population follow-up basis.

Keywords: Gleason score ≥7; PSA velocity; percentage free PSA; population screening; prostate cancer; repeat biopsy.