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.

Inclusion criteria

• Pathologically confirmed prostate cancer, with a plan to receive radiation therapy for either definitive (cohort A) or salvage (cohort B) therapy. Patients without planned androgen deprivation therapy (ADT) will be accrued to cohort C

• Cohort A will be restricted to Gleason grade group 3 or higher (4+3 or 8-10) so that androgen deprivation will be indicated
• Cohort B will not be restricted by Gleason grade but will require rising prostate-specific antigen (PSA) and a plan for ADT with salvage radiation
• Cohort C will be prostate cancer patients in whom definitive or salvage radiation is planned without ADT
• Patients must be age 18 or older
• Willing to provide urine and stool samples at specified time points

Exclusion criteria

• Men with inflammatory bowel disease or pre-existing cystitis will be excluded