Hormone Therapy and Intensity-Modulated Radiation Therapy in Treating Patients With Metastatic Prostate Cancer

Inclusion Criteria: * Patients with histologically proven diagnosis of adenocarcinoma of the prostate stage N1, N2, N3, M1a, M1b, M1c with =\< 5 metastatic lesions; if the diagnosis of metastasis in the lymph node is based solely on imaging computed tomography (CT) scan or magnetic resonance imaging (MRI), the longitudinal diameter of the lymph node has to be \>= 2.0 cm; if the lymph node is positive on positron emission tomography (PET) or ProstaScint scan, the longitudinal diameter of the lymph node on CT scan or MRI has to be \>= 1.5 cm * Patients who have measurable disease must have had X-rays, scans or physical examination used for tumor measurement completed within 28 days prior to registration; patients must have non-measurable disease assessed within 42 days prior to registration * Patients must have had documented PSA of \> 2 prior to onset of androgen deprivation * Patients might have received up to 36 weeks of adjuvant androgen deprivation therapy and up to 36 weeks of androgen deprivation therapy for metastatic disease prior to enrollment to this study; patients may be on androgen deprivation for metastatic disease at the time of enrollment to the protocol; adjuvant therapy must have been completed at least 2 years before androgen deprivation for metastatic disease and patients must remain hormone sensitive * Prior radiation therapy for metastatic disease is not allowed * Prior chemotherapy for metastatic disease is not allowed; prior neoadjuvant and adjuvant ch…