Effect of Radiotherapy Variables on Circulating Effectors of Immune Response and Local Microbiome

Cohort 1a and b: Prostate cancer subjects undergoing 9 week radiation Inclusion criteria: * Biopsy-proven diagnosis of prostate adenocarcinoma * Age ≥ 18 Exclusion criteria: * History of prior pelvic radiation (external beam or brachytherapy) * Prior or concurrent lymphomatous/hematogenous malignancy, or history of prior/concurrent invasive malignancy during the past 5 years * History of hormone therapy such as LHRH agonists (gosrelin, leuprolide), anti-androgens (flutamide, bicalutamide), surgical castration (orchiectomy) * History of irritable bowel disease * Evidence of lymph node involvement or metastatic disease Cohort 2a : Breast cancer subjects undergoing standard fractionation RT of 5 weeks Inclusion criteria: * Biopsy-proven diagnosis of invasive breast cancer, s/p breast surgery to negative margins, and requiring adjuvant breast and nodal RT * Age ≥ 18 Exclusion criteria: * History of prior radiation therapy to the ipsilateral breast * Prior or concurrent lymphomatous/hematogenous malignancy, or history of prior/concurrent invasive malignancy during the past 5 years * \< 1 month from completion of chemotherapy to start of RT * Evidence of metastatic disease Cohort 2b: Breast cancer subjects undergoing PBI Inclusion criteria: * Post-menopausal women defined as either 1) at least 2 years without menstrual period or 2) or patients older than 50 with serological evidence of post-menopausal status or 3) hysterectomized patients of any age with FSH confirmation of post-menopausal status. * Post-segmental mastectomy with negative margins * If bilateral, pT1 breast cancer, excised with negative margins AND/OR * pTis excised with negative margins * Clinically N0 or pN0 or sentinel node negative * Diagnosis of ductal carcinoma in situ DCIS, limited to \<2cm size of DCIS and to lesions of low or intermediate grade, excised (or re-excised) with final negative margins ( no DCIS on inked margins). * Age ≥ 18 Exclusion criteria: * History of prior radiation therapy to the ipsilateral breast * Presence of a proportion of DCIS in the core biopsy specimen which is compatible with extensive intraductal component (EIC). * \< 1 month from completion of chemotherapy to start of RT * Evidence of metastatic disease