Digital rectal examination (DRE), though limited in diagnostic accuracy, remains a conventional tool in prostate cancer screening. With the advent of multiparametric MRI, this study evaluated cancer detection rates across MRI-fusion, transperineal, and transrectal biopsies, stratified by DRE status. MRI-fusion biopsy outcomes were further analyzed by Prostate Imaging–Reporting and Data System (PIRADS) scores to clarify the role of DRE and inform optimal biopsy strategies.

This retrospective cohort study was conducted at Taichung Veterans General Hospital in Taiwan. A total of 853 patients undergoing prostate biopsy were enrolled, categorized into two groups based on DRE results: DRE-positive (n = 434) and DRE-negative (n = 419). Demographic and clinical characteristics including age, prostate-specific antigen (PSA) levels, prostate volume, and PSA density were compared between the two groups. Cancer detection rates among biopsy methods (MRI-guided, transperineal, and transrectal biopsies) were statistically analyzed, with further subgroup analysis according to PIRADs scores (III–V) in the DRE-negative cohort receiving MRI-guided biopsies.

Patients in the DRE-positive group were significantly older, higher PSA levels, smaller prostate volumes, and higher PSA density compared to the DRE-negative group(Table1).Prostate cancer detection rates were significantly higher in patients with positive DRE findings (69.6% vs. 43.4%, p < 0.001) In the DRE-positive cohort, biopsy method significantly impacted detection rates (p = 0.020), with post-hoc analyses (Bonferroni adjusted α = 0.0167) showing a significantly higher detection rate with transperineal biopsy compared to MRI-fusion biopsy (74.7% vs. 54.8%, p = 0.0145); however, there was no significant difference between MRI-guided and transrectal biopsies or between transperineal and transrectal biopsies. No statistically significant differences were observed among biopsy methods in the DRE-negative cohort (p = 0.131)(Figure1). Further analysis of MRI-fusion biopsy results in DRE-negative patients revealed detection rates of 18.75% (PIRADs III), 39.22% (PIRADs IV), and 72.73% (PIRADs V). Compared with the overall detection rate across all biopsy methods (43.44%), PIRADs V patients showed a significantly higher detection rate (p = 0.031), while PIRADs III (p = 0.252) and IV (p = 0.638) showed no significant difference(Figure2).

Digital rectal examination (DRE) remains a useful clinical tool for prostate cancer detection. Patients with positive DRE findings showed significantly higher detection rates, suggesting that conventional biopsy methods are sufficient without MRI. In DRE-negative patients, cancer detection rates increased with PIRADS scores—from 18.75% (PIRADS III) to 72.73% (PIRADS V)—supporting the role of MRI in guiding biopsy decisions and reducing unnecessary procedures.