Multicenter Validation of a Risk Classification Cluster for Unfavorable Pathology in Prostatectomy Specimens of Patients with an Active Surveillance Expanded Inclusion Criteria

Background: Active surveillance (AS) criteria in prostate cancer (PCa) are expanding to include selected patients with intermediate-risk features. This multicenter retrospective study aimed to validate a proposed risk group (RG) classification for predicting unfavorable pathology (UP) in radical prostatectomy specimens among patients eligible for AS under expanded criteria. Methods: Patients from three Andalusian university hospitals who met the AS criteria, defined as prostate-specific antigen (PSA) ≤ 20 ng/mL, International Society of Urological Pathology (ISUP) ≤ 2, and clinical stage ≤ cT2, were included. The patients were stratified into five RGs according to PSA density, Prostate Imaging Reporting and Data System score (PI-RADS), and clinical stage. UP was defined as ≥pT3a and/or pN+ and/or ISUP grade ≥ 3. Results: A total of 244 patients were analyzed. The median age was 63 years, the median PSA 5.98 ng/mL, and the median PSA density was 0.14 ng/cc. UP was identified in 47.1% of radical prostatectomy specimens, increasing progressively across RGs from 20.8% to 93.3%. Each incremental RG was associated with a higher risk of UP, with an odds ratio of 2.14 and moderate predictive accuracy, as reflected by an area under the curve of 0.70. Conclusions: The proposed RG classification showed moderate predictive capacity for UP and may improve risk stratification in intermediate-risk patients considered for AS.