Study to Detect Changes in Urinary and Gut Microbiome During Androgen Deprivation Therapy and Radiation Therapy in Patients With Prostate Cancer

PRIMARY OBJECTIVE: I. To determine the feasibility of identifying changes in urine and gut microbiomes during androgen deprivation therapy and radiation therapy for prostate cancer. SECONDARY OBJECTIVE: I. To explore associations between baseline microbiomes and urinary or gastrointestinal radiation toxicity by Common Terminology Criteria for Adverse Events (CTCAE) and Patient Reported Outcomes (PRO). OUTLINE: Patients undergo collection of stool and urine samples within 2 weeks before hormone therapy or radiation therapy, after hormone therapy but before start of radiation therapy, and after completion of radiation therapy. Patients also complete a series of questionnaires prior to starting radiation therapy, mid-way through radiation therapy, and after completion of radiation therapy (within 1-3 weeks, at 3 months, and then every 6 months until 3 years from radiation completion). Patients' medical records are also reviewed.