Randomized Phase II Trial of Targeted Radiation With no Castration for Mcrpc

This study tests whether targeted radiation therapy (called SBRT) to all visible cancer sites — without continued hormone therapy (castration) — can treat castration-resistant prostate cancer that has spread to a limited number of sites. This approach may allow some patients to avoid ongoing hormonal side effects. **You may be eligible if...** - You are 18 or older with castration-resistant prostate cancer (cancer growing despite very low testosterone) - Your cancer has spread to no more than 10 sites visible on PSMA PET and FDG PET scans - Your cancer has progressed despite prior hormone-blocking drugs - Your overall health is adequate (ECOG 0-2) - Your blood counts and organ function are within acceptable ranges **You may NOT be eligible if...** - Your cancer has spread to the liver or brain (lung metastases are allowed) - Your tumor type is small cell or neuroendocrine carcinoma - You have a visceral organ metastasis to the liver - You have current spinal cord compression or urgent need for palliative radiation - You have active infection requiring antibiotics - You have a psychiatric or substance abuse condition that could interfere with participation Talk to your doctor to see if this trial is right for you.