Androgen-Deprivation Therapy and Radiation Therapy in Treating Patients With Prostate Cancer

DISEASE CHARACTERISTICS: Pathologically (histologically or cytologically) proven diagnosis of prostatic adenocarcinoma within 180 days of registration at moderate to high risk for recurrence as determined by one of the following combinations: * Gleason score 7-10 + T1c-T2b (palpation) + PSA \< 50 ng/ml (includes intermediate and high risk patients); * Gleason score 6 + T2c-T4 (palpation) + PSA \< 50 ng/ml -ORGleason score 6 + ≥ 50% (positive) biopsies + PSA \< 50 ng/ml; * Gleason score 6 + T1c-T2b (palpation) + PSA \> 20 ng/ml. Patients previously diagnosed with low risk prostate cancer undergoing active surveillance who are re-biopsied and found to have unfavorable intermediate risk disease or favorable high risk disease according to the protocol criteria are eligible for enrollment within 180 days of the repeat biopsy procedure. * History/physical examination (to include at a minimum digital rectal examination of the prostate and examination of the skeletal system and abdomen) within 90 days prior to registration. * Clinically negative lymph nodes as established by imaging (pelvic ± abdominal CT or MR), (but not by nodal sampling, or dissection) within 90 days prior to registration. * Patients with lymph nodes equivocal or questionable by imaging are eligible if the nodes are ≤ 1.5 cm. \*No evidence of bone metastases (M0) on bone scan within 120 days prior to registration (Na F PET/CT is an acceptable substitute). * Equivocal bone scan findings are allowed if plain films (or CT or MRI) are negative for metastasis. \*Baseline serum PSA value performed with an FDA-approved assay (e.g., Abbott, Hybritech) within 120 days prior to registration. * Study entry PSA should not be obtained during the following time frames: (1) 10- day period following prostate biopsy; (2) following initiation of hormonal therapy; (3) within 30 days after discontinuation of finasteride; (4) within 90 days after discontinuation of dutasteride. * Zubrod Performance Status 0-1(unless otherwise specified); * Age ≥ 18; * CBC/differential obtained within 60 days prior to registration on study, with adequate bone marrow function defined as follows: * Absolute neutrophil count (ANC) ≥ 1,500 cells/mm3; * Platelets ≥ 100,000 cells/mm3; * Hemoglobin ≥ 8.0 g/dl (Note: The use of transfusion or other intervention to achieve Hgb ≥ 8.0 g/dl is acceptable.); * Patient must be able to provide study specific informed consent prior to study entry.