Context-dependent role of digital rectal examination in a contemporary prostate biopsy cohort: differential predictive value with and without multiparametric magnetic resonance imaging

Abstract

Objective

To quantify the context-dependent contribution of digital rectal examination (DRE) to the prediction of clinically significant prostate cancer (csPCa, International Society of Urological Pathology [ISUP] grade group ≥2) in a contemporary biopsy cohort, comparing a nonmultiparametric magnetic resonance imaging (mpMRI) clinical pathway with an mpMRI-informed pathway including prostate imaging–reporting and data system (PI-RADS).

Materials and methods

We performed a retrospective analysis of 666 consecutive prostate biopsies at a single academic center (July 2017–December 2024). DRE was performed by urology residents and attending urologists. Two multivariable logistic regression models were constructed: Model A (full cohort, n = 612) included age, log-prostate-specific antigen (PSA), log-PSA density (PSAD), prior biopsy, and DRE; Model B (mpMRI subcohort, N = 306) additionally included PI-RADS score. Discrimination was assessed using area under the curve (AUC) and likelihood ratio tests. Sensitivity analyses evaluated any cancer (ISUP ≥1) and high-grade cancer (ISUP ≥4).

Results

csPCa prevalence was 30.7% (202/660), and DRE was suspicious in 52.3% (346/662). In Model A, DRE was independently associated with csPCa (adjusted odds ratio [aOR], 2.18, 95% confidence interval [CI]: 1.45–3.28, P < 0.001), although the gain in discrimination was modest (ΔAUC = 0.009). In Model B, DRE showed borderline significance (aOR, 1.88, 95% CI: 1.01–3.52, P = 0.048) with negligible discrimination gain (ΔAUC = 0.002). Sensitivity analyses showed consistent findings. A dose–response gradient was observed: csPCa rates were 19.2% (normal), 31.6% (cT2a), and 58.9% (cT2b–T4) (p-trend <0.0001).

Conclusions

DRE was independently associated with csPCa in the absence of mpMRI, but its incremental discriminative contribution was modest and became negligible once PI-RADS was incorporated. These findings support a limited, context-dependent role for DRE in contemporary biopsy pathways.