Risk-adapted Omission of Systematic Cores in PI-RADS 3 Lesions Based on Prostate-specific Antigen Density, Biopsy Route, and Targeted Core Number: A Multicentre Cohort Study
Background: Prostate Imaging Reporting and Data System (PI-RADS) category 3 lesions represent an intermediate-risk group for which the additional diagnostic value of systematic biopsy (SBx) after multiparametric magnetic resonance imaging (mpMRI)-targeted biopsy (TBx) remains uncertain. Objective: To quantify the absolute omission cost of a TBx-only strategy compared with overall biopsy (OBx; TBx plus SBx) and to assess whether this cost varies according to prostate-specific antigen density (PSAD), biopsy route, and targeted sampling intensity. Design, setting, and participants: This retrospective multicentre cohort study included 902 men with exclusively PI-RADS 3 lesions on prebiopsy mpMRI who underwent index software-assisted mpMRI-ultrasound fusion biopsy at six academic and high-volume centres between January 2016 and March 2023.
Intervention: All patients underwent same-session TBx and SBx via either the transperineal (TP) or transrectal (TR) route.
Outcome measurements and statistical analysis: The primary outcome was the absolute cohort-level proportion of clinically significant prostate cancer (csPCa), defined as International Society of Urological Pathology (ISUP) grade group ≥2, detected by OBx but missed by TBx. Paired detection rates were compared using the McNemar test, and the omission cost was estimated with exact confidence intervals (CIs). An exploratory 5% margin was used to contextualise the performance of TBx alone. Factors associated with TBx failure were evaluated using multivariable Firth penalised logistic regression. A sensitivity analysis defined csPCa as ISUP grade group ≥3.
Results and limitations: TBx detected csPCa in 181 of 902 men (20%), whereas OBx detected csPCa in 240 (27%). TBx alone missed 59 cases, corresponding to an absolute omission cost of 6.5% (95% CI 5.0-8.4), which exceeded the prespecified exploratory 5% benchmark. When csPCa was defined as ISUP grade group ≥3, the omission cost decreased to 2.8% (25/902; 95% CI 1.8-4.1). The lowest omission cost was observed among men undergoing TP biopsy with PSAD <0.10 ng/ml/cm3 (0.8%, 1/126; 95% CI 0.02-4.3). Each additional targeted core was independently associated with lower odds of TBx failure (adjusted odds ratio 0.69, 95% CI 0.54-0.86). Limitations include the retrospective design, centre-level heterogeneity in mpMRI interpretation and biopsy practices, nonrandom biopsy-route selection, the use of same-session combined biopsy rather than whole-mount pathology as the reference standard, and the absence of core-by-core spatial mapping.
Conclusions: TBx alone should not be considered a universal substitute for OBx in men with PI-RADS 3 lesions when csPCa is defined as ISUP grade group ≥2. The lower omission cost observed when a stricter threshold for significant disease was applied, and in selected men with low PSAD undergoing TP biopsy, supports prospective evaluation of risk-adapted biopsy deintensification. However, these exploratory findings do not justify the routine omission of SBx.
Buhas, B., Mjaess, G., Diamand, R., Peyrottes, A., Uleri, A., Baboudjian, M., Brown, J., Abou Chakra, M., Borz, M., Crisan, N., Baudewyns, A., Jabbour, T., Jeglinschi, S., Iancu, M., & Ploussard, G. (2026). Risk-adapted Omission of Systematic Cores in PI-RADS 3 Lesions Based on Prostate-specific Antigen Density, Biopsy Route, and Targeted Core Number: A Multicentre Cohort Study. European Urology Oncology, n/n/a. https://doi.org/10.1016/j.euo.2026.07.003 (Original work published 2026)