Hypofractionated Whole-Pelvis Radiotherapy (WPRT) vs Conventionally-Fractionated WPRT in Prostate Cancer

The purpose of this research study is to determine if 5 (five) fractions of external radiotherapy with higher radiation doses per fraction to the pelvis leads to similar results to the standard of care external radiotherapy treatment that is comprised of 25 fractions of external radiotherapy with lower radiation doses per fraction to the pelvis. This study aims to investigate the impact in quality of life associated with hypofractionated Whole Pelvis Radiotherapy (WPRT) in comparison to conventionally-fractionated WPRT in patients with unfavorable-intermediate and high-risk prostate cancers. This information is valuable as hypofractionated WPRT is a more attractive and convenient treatment approach, and may become the new standard of care if proven to be well-tolerated and effective. Therefore, this study aims to provide a more rational justification for use of hypofractionated WPRT in future larger randomized trials by comparing this strategy with the current standard of care. This study will also provide an initial understanding of the toxicity profile and cancer control associated with hypofractionated WPRT and High Dose Rate Brachytherapy (HDR-BT).

Inclusion Criteria: * Age 18 or older * Study Informed Consent provided * Pathologically proven diagnosis of prostatic adenocarcinoma * Unfavorable intermediate risk \[with greater than 15% chance of node involvement based on Memorial Sloan Kettering Cancer Center (MSKCC) nomogram https://www.mskcc.org/nomograms/prostate\] or high or very-high-risk prostate cancer based on National Comprehensive Cancer Network (NCCN) classification \[Prostatic Specific Antigen (PSA) \> 20 ng/mL or clinical cT3a or cT3b or Gleason 8-10\] * Eastern Cooperative Oncology Group (ECOG) Performance Status 0-1 * No prior history of pelvic irradiation, brachytherapy, cryosurgery, High-Intensity Focused Ultrasound (HIFU), Transurethral Resection of the Prostate (TURP) or radical prostatectomy Exclusion Criteria: * Presence of nodal or distant metastasis, as confirmed by Magnetic Resonance Imaging (MRI) or Computerized Tomography (CT) of the chest/abdomen/pelvis and bone scan within 45 days of randomization * Plan for adjuvant docetaxel post-radiotherapy * Serious medical comorbidities or other contraindications to HDR-BT * Presence of inflammatory bowel disease * Presence of connective tissue disease * Medically unfit for general anesthesia * Unable or unwilling to complete questionnaires