Inclusion Criteria: 

• Histologically confirmed prostate adenocarcinoma at the time of surgery.
• Pathologic stages T2-T3b, Nx or N0-1, M0-1 as staged by the pathology report (AJCC Criteria 8th Ed.).
• PSA post radical prostatectomy ≥ 0.1 and < 2.0 ng/mL within 90 days prior to enrollment, obtained at least 6 weeks after surgery.
• ECOG performance status 0-2 assessed within 90 days of enrollment.
• Patients must sign IRB approved study specific informed consent.
• Patients must complete all required pre-entry tests listed in section 4.0 within the specified time frames.
• Patients must be able to start treatment (ADT or radiation) within 120 days of study registration.
• Patients must be at least 18 years old.

Exclusion Criteria: 

• Previous pelvic radiation.
• Prior androgen deprivation therapy for prostate cancer and PSA ≥ 0.1 ng/mL.
• Active rectal diverticulitis, Crohn’s disease affecting the rectum, or ulcerative colitis (non-active diverticulitis and Crohn’s disease not affecting the rectum are allowed).
• Prior systemic chemotherapy for prostate cancer.
• History of proximal urethral stricture requiring dilatation.
• Major medical, addictive, or psychiatric illness which in the investigator’s opinion, will prevent the consent process, completion of the treatment and/or interfere with follow-up. (Consent by legal authorized representative is not permitted for this study).           
• History of myocardial infarction or decompensated CHF within the last 6 months.
• On a transplant list.

Note: Other protocol defined Inclusion/Exclusion Criteria may apply.

Eligibility last updated 8/31/22. Questions regarding updates should be directed to the study team contact.