The Performance of Abnormal Digital Rectal Examination for the Detection of Prostate Cancer at Stratified Prostate Specific Antigen Levels

Abstract

Objective: Our aim was to determine the performance of abnormal digital rectal examination (DRE) in prostate cancer detection at different PSA levels. Methods: A total of 1612 patients having abnormal DRE and/or elevated PSA whom underwent TRUS guided prostate biopsies were included in the study. Any palpable induration or nodularity was accepted as abnormal DRE findings. Pathologic features of biopsy specimens were compared within groups according to DRE findings and serum PSA level groups of 2.5 - 4, 4 - 10 and >10 ng/ml. Results: Abnormal DRE was detected in 339 patients; of whom 48.7% were determined to have cancer. Cancer detection rates of patients having abnormal DRE were found to be 20%, 31.5% and 68% at PSA ranges 2.5-4, 4-10 and > 10 ng/ml, respectively. Significantly higher grade cancers were detected by abnormal DRE at each PSA group. The positive and negative predictive values of abnormal DRE according to groups of PSA 2.5 - 4, 4 - 10 and > 10 ng/ml were 20% and 84.1%, 31.5% and 80.6%, 68% and 66.6%, respectively. Conclusion: At each PSA group DRE resulted in detecting significantly more cancers with Gleason score > 7. Although predictive value of abnormal DRE diminishes with concomitantly decreasing PSA levels, significance of DRE in the diagnosis of prostate cancer cannot be ignored.