The Maximum Standardized Uptake Value in Patients with Recurrent or Persistent Prostate Cancer after Radical Prostatectomy and PSMA-PET-Guided Salvage Radiotherapy – A Multicenter Retrospective Analysis

Purpose/Objective(s) Recurrence rate after salvage radiotherapy (sRT) is heterogeneous and additional prognostic markers are needed to improve risk-stratification guide personalized treatment. We evaluated the association of maximum standardized uptake value (SUVmax) in positron-emission tomography targeting prostate-specific-membrane-antigen (PSMA-PET) prior sRT on biochemical recurrence free survival (BRFS) a large multicenter cohort. Materials/Methods Patients who underwent 68Ga-PSMA11-PET radical prostatectomy (RP) due or PSA-persistence were enrolled four high-volume centers this retrospective study. Only patients with PET-positive local (LR) and/or nodal (NR) within pelvis included. treated intensity-modulated-sRT prostatic fossa elective lymphatics case disease. Dose escalation was delivered LR NR. Androgen deprivation therapy administered at discretion treating physician.LR NR manually delineated using SUVmax extracted for Cox-regression performed analyze impact clinical parameters SUVmax-derived values BRFS, defined as serum prostate-specific-antigen >0.2 ng/ml above post-sRT-nadir without initiation therapies death any cause. Results 235 median follow up (FU) 24 months included final The presence associated favorable BRFS (p=0.016). Presence unfavorable (p=0.007). While there trend ≥ (p=0.071), 75%quartile significantly (p=0.022, HR: 2.1, 95%CI 1.1-4.6). not BRFS. stayed significant multivariate analysis (p=0.030). Sensitivity had FU >12 (n=197) confirmed these results. Conclusion In recurrence/persistence RP, PSMA-expressing pelvic lymph nodes PET less salvage-radiotherapy. non-invasive biomarker can prognosticate outcome undergoing confined PSMA-PET.