Randomized Phase II Trial Comparing 2- and 5-Fraction Prostate Stereotactic Ablative Radiotherapy Using AI Guidance for Intermediate Risk Prostate Cancer

What this Trial Is About

Prostate cancer is a common cancer in men and a major cause of cancer-related death. Researchers are comparing two forms of prostate stereotactic ablative radiotherapy SABR, a precise radiation treatment, using either 2 or 5 treatment sessions fractions for men with intermediate risk prostate cancer. This phase II randomized trial also explores the use of an artificial intelligence AI guided dose application to improve radiation targeting during treatment. Participants will be randomly assigned to receive either 27Gy in 2 fractions over 2 weeks or 40Gy in 5 fractions over 2 weeks. All patients will have fiducial markers and a rectal spacer implanted before treatment to reduce side effects. Treatment planning involves CT and MRI imaging, and real-time prostate tracking will be used during therapy. The AI dose guidance tool will be evaluated offline, without affecting actual treatment. Participants will undergo baseline and follow-up assessments including PSA and testosterone tests, toxicity evaluations using standard scales, and questionnaires on bowel, bladder, and sexual quality of life. Follow-up will continue for 5 years after treatment to monitor long-term side effects, disease control, and quality of life. The main outcome is freedom from grade 2 or higher toxicity four years after treatment, with secondary outcomes including acute toxicity, biochemical control, and feasibility of AI-guided dose application.

Phase II Randomized Trial of 2 Versus 5 Fraction Prostate Stereotactic Ablative Radiotherapy for Intermediate Risk Prostate Cancer