Prostate SABR With Intra-Prostatic SABR Boost

This study is testing a radiation therapy approach called SABR (stereotactic ablative radiotherapy) for prostate cancer that delivers an extra high dose (boost) to the area inside the prostate where the cancer is most concentrated, to improve cancer control. **You may be eligible if...** - You have been diagnosed with prostate cancer confirmed by biopsy (adenocarcinoma) - Your cancer is classified as high-risk (at least one of: stage T3, Gleason score 8–10, or PSA above 20 ng/mL) - You are willing to provide informed consent **You may NOT be eligible if...** - You have had radiation therapy to the pelvis before - You have conditions that make radical prostate radiation unsafe (e.g., connective tissue disease, inflammatory bowel disease) - You cannot have a prostate MRI - Your prostate cancer has clearly spread to lymph nodes outside the pelvis or to other parts of the body Talk to your doctor to see if this trial is right for you.