Active Surveillance in Prostate Cancer With Intermediate-Risk Features: The PRIAS-JAPAN Study

ObjectivesTo report outcomes of active surveillance (AS) for prostate cancer in men with intermediate-risk features of International Society of Urological Pathology (ISUP) grade group 2 and/or clinical stage T2 compared with ISUP grade group 1 and clinical stage T1 in the PRIAS-JAPAN study.MethodsPatients with prostate cancer diagnosed between January 2010 and February 2024 were included in this study. PSA test, rectal examination, and re-biopsy were performed regularly. We calculated the pathological reclassification rate, program persistence rate, and subsequent treatment.ResultsData from 1302 participants were collected. After excluding patients who did not fit inclusion criteria (n = 28) or follow-up of less than 1 year (n = 208), 1066 patients were included in this analysis. The median follow-up was 42.4 months (interquartile range 17.0-72.1). There were no statistical differences in the pathological reclassification, persistence rates, and subsequent therapy between low- and intermediate-risk features.ConclusionThis preliminary study demonstrated medium-term outcomes of AS in prostate cancer with intermediate-risk features in Japan, suggesting no significant difference in the pathological reclassification, persistence rate, and subsequent therapy between low- and intermediate-risk features.