Trial of ADT and SBRT Versus SBRT for Intermediate Prostate Cancer

Inclusion Criteria: * Biopsy proven intermediate risk prostate cancer, which includes patients with any one of the following variables: * Gleason 7 disease * PSA 10-20 ng/ml * Clinical T2b-T2c disease Note: Patients who only have radiographic evidence of T3 disease (i.e. extracapsular extension, or seminal vesical invasion radiographically) will not be excluded. * Serum testosterone ≥ 240 ng/dL determined within 2 months prior to enrollment * At least 4 weeks must have elapsed from major surgery * KPS ≥ 80% * Prostate size as determined on MRI to be \< 90 cc. Prostate size can be determined on CT scan if MRI is not available. * 18 years of age or older * IPSS ≤ 20 * Patient must be available for follow-up. After 2 years of follow-up following post-treatment biopsy, telephone-based follow-up will be acceptable * Laboratory test findings within 8 weeks of randomization: * Adequate hepatic function with serum bilirubin ≤ 1.5 times the upper institutional limits of normal (ULN), ALT and AST ≤ 2.5 x ULN. Patients with a history of Gilbert's syndrome may be enrolled if the total bilirubin is \< 3 mg/dL with a predominance of indirect bilirubin * Adequate renal function with serum creatinine ≤ 1.5 x ULN * Adequate hematologic function with absolute neutrophil counts ≥ 1,500 cell/mm3 and platelets ≥ 100,000 cells/mm3 and hemoglobin value ≥ 9 g/dL (Note: patients whose anemia has been corrected to a hemoglobin value ≥ 9 g/dL with blood transfusions are allowed) Exclusion Criteria: * CT or MRI evidence of metastatic disease to the bone. * Patients with one or more positive lymph nodes considered suspicious as determined by clinical assessment on MRI or CT * Prior treatment for prostate cancer, including history of chemotherapy, hormonal therapy within 30 days of enrollment or surgery for prostate cancer (except for prior TURP or greenlight PVP which would be allowed) * History of another malignancy within the previous 3 years except for the following: adequately treated basal cell or squamous cell skin cancer, superficial bladder cancer, currently in complete remission, or any other cancer that has been in complete remission for at least 3 years * Patients with Crohn's disease or ulcerative colitis