External validation and comparison of magnetic resonance imaging-based risk prediction models for prostate biopsy stratification.

PURPOSE: Magnetic resonance imaging (MRI) is a promising tool for risk assessment, potentially reducing the burden of unnecessary prostate biopsies. Risk prediction models that incorporate MRI data have gained attention, but their external validation and comparison are essential for guiding clinical practice. The aim is to externally validate and compare risk prediction models for the diagnosis of clinically significant prostate cancer (csPCa). METHODS: A cohort of 4606 patients across fifteen European tertiary referral centers were identified from a prospective maintained database between January 2016 and April 2023. Transrectal or transperineal image-fusion MRI-targeted and systematic biopsies for PI-RADS score of ≥ 3 or ≥ 2 depending on patient characteristics and physician preferences. Probabilities for csPCa, defined as International Society of Urological Pathology (ISUP) grade ≥ 2, were calculated for each patients using eight models. Performance was characterized by area under the receiver operating characteristic curve (AUC), calibration, and net benefit. Subgroup analyses were performed across various clinically relevant subgroups. RESULTS: Overall, csPCa was detected in 2154 (47%) patients. The models exhibited satisfactory performance, demonstrating good discrimination (AUC ranging from 0.75 to 0.78, p < 0.001), adequate calibration, and high net benefit. The model described by Alberts showed the highest clinical utility for threshold probabilities between 10 and 20%. Subgroup analyses highlighted variations in models' performance, particularly when stratified according to PSA level, biopsy technique and PI-RADS version. CONCLUSIONS: We report a comprehensive external validation of risk prediction models for csPCa diagnosis in patients who underwent MRI-targeted and systematic biopsies. The model by Alberts demonstrated superior clinical utility and should be favored when determining the need for a prostate biopsy.

Transperineal or Transrectal Magnetic Resonance Imaging-targeted Biopsy for Prostate Cancer Detection.

BACKGROUND AND OBJECTIVE: A notable paradigm shift has emerged in the choice of prostate biopsy approach, with a transition from transrectal biopsy (TRBx) to transperineal biopsy (TPBx) driven by the lower risk of severe urinary tract infections. The impact of this change on detection of clinically significant prostate cancer (csPCa) remains a subject of debate. Our aim was to compare the csPCa detection rate of TRBx and TPBx. METHODS: Patients who underwent magnetic resonance imaging (MRI)-targeted and systematic biopsies for clinically localized PCa at 15 European referral centers from 2016 to 2023 were included. A propensity score matching (PSM) analysis was performed to minimize selection biases. Logistic regression models were used to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CIs). KEY FINDINGS AND LIMITATIONS: Of 3949 patients who met the study criteria, 2187 underwent TRBx and 1762 underwent TPBx. PSM resulted in 1301 matched pairs for analysis. Patient demographics and tumor characteristics were comparable in the matched cohorts. TPBx versus TRBx was associated with greater detection of csPCa, whether defined as International Society of Urological Pathology grade group ≥2 (51% vs 45%; OR 1.37, 95% CI 1.15-1.63; p = 0.001) or grade group ≥3 (29% vs 23%; OR 1.38, 95% CI 1.13-1.67; p = 0.001). Similar results were found when considering MRI-targeted biopsy alone and after stratifying patients according to tumor location, Prostate Imaging-Reporting and Data System score, and clinical features. Limitations include the retrospective nature of the study and the absence of centralized MRI review. CONCLUSIONS: Our findings bolster existing understanding of the additional advantages offered by TPBx. Further randomized trials to fully validate these findings are awaited. PATIENT SUMMARY: We compared the rate of detection of clinically significant prostate cancer with magnetic resonance imaging (MRI)-guided biopsies in which the sample needle is passed through the perineum or the rectum. Our results suggest that the perineal approach is associated with better detection of aggressive prostate cancer.