EBRT and HDR Brachytherapy for Unfavorable-intermediate, High, and Very High-risk Prostate Cancer

EBRT will be administered every 5 consecutive days for 5 consecutive weeks. This is standard of care practice for this therapy. This may be revised as applicable per treating physician discretion. The dose of radiation will be in accordance with standard clinical practice guidelines for the treatment of prostate cancer.

HDR brachytherapy will be administered per standard clinical practice (per NCCN guidelines version 1.2020 for prostate cancer), however standard clinical practice may vary between clinicians. Therefore, the dose of 15Gy in 1 fraction and a set of dosimetry guidelines are to be followed for the purposes of this study. A diagnostic MRI will be co-registered with Transrectal Ultrasound (TRUS) to perform the HDR brachytherapy.

The dosing and administration of ADT will be in accordance with the drug label for the drug(s) used for this purpose. Participants may receive ADT before and/or during the course of this study.