Study of PSMA PET/CT Imaging to Help Select Men With Low-Risk Prostate Cancer for Active Surveillance

This is a multicenter, prospective diagnostic accuracy study evaluating the Istanbul PSMA PET/CT Criteria (IPPC) for selecting patients with biopsy-confirmed low-risk prostate cancer (ISUP Grade 1) for active surveillance (AS). The study integrates delayed Ga-68 PSMA PET/CT imaging into the diagnostic pathway to refine patient stratification, minimize overtreatment and potentially reduce unnecessary biopsies and MRI, or exposing high-risk individuals to the danger of cancer progression if left untreated scans.

Prostate cancer is the most common malignancy in men and demonstrates heterogeneous clinical behavior. While many low-risk patients have indolent disease, a subset harbors clinically significant prostate cancer (csPCa) requiring early intervention. Active Surveillance (AS) is widely used to avoid overtreatment; however, current selection criteria-PSA, DRE, biopsy Gleason score, number of positive cores, PSA density, and mpMRI-lack sufficient predictive accuracy. Studies indicate that up to 30% of patients classified as low-risk by biopsy are found to have higher-grade disease at radical prostatectomy. The Istanbul PSMA PET/CT Criteria (IPPC) were developed by a multidisciplinary expert panel in Turkey to classify intraprostatic lesions on delayed (120-minute) Ga-68 PSMA PET/CT imaging into three risk categories: * IPPC 1 No or homogeneous low uptake - safe for monitoring. * IPPC 2: Indeterminate uptake - AS with close follow-up. * IPPC 3: Focal, lentiform, high SUVmax ≥12 uptake in peripheral zone - definitive treatment recommended. This study will evaluate the diagnostic performance of IPPC compared to standard mpMRI and biopsy findings, using radical prostatectomy pathology or long-term clinical follow-up as the reference standard.