Vlissingen

Researchers are studying men who have prostate cancer that returned after surgery, specifically those with biochemical recurrence detected by rising PSA levels but no spread to lymph nodes or distant sites. The trial aims to find out if increasing the dose of radiation therapy using a shorter, more intense schedule can improve cancer control compared to the standard radiation treatment. This is a phase III randomized trial led by the University Medical Center Groningen that focuses on men with PSA levels under 1.0 ngmL after radical prostatectomy. Participants will be assigned to one of two groups one receiving conventional salvage external beam radiation therapy sEBRT delivering 70 Gy total in 35 daily fractions over 7 weeks, or the other receiving hypofractionated sEBRT delivering 60 Gy total in 20 fractions over 4 weeks. The study compares these two radiation schedules to see if the shorter, higher-dose approach offers better outcomes. Both treatments are guided by PSMA-PET imaging to confirm no metastases. During the study, men will have regular follow-up visits for up to 5 years to monitor progression-free survival and side effects. Researchers will assess acute and late gastrointestinal and genitourinary toxicities, quality of life, metastasis-free survival, prostate cancer-specific mortality, and overall survival. The primary outcome is the 5-year progression-free survival after radiation therapy. Participants will undergo PSA testing, clinical evaluations, and quality of life questionnaires throughout the study period.