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

PRIMARY OBJECTIVES: I. To evaluate the time to prostate-specific antigen (PSA) relapse in patients with oligometastatic (=\< 5 lesions) hormone-sensitive prostate cancer treated with 36 weeks of androgen deprivation therapy and localized radiotherapy to all known tumor sites. II. To assess the prostate-specific-antigen (PSA) and objective response rate to treatment with 36 weeks of androgen deprivation and localized radiotherapy in patients with oligometastatic hormone-sensitive prostate cancer. III. To assess the toxicity of 36 weeks of androgen deprivation and localized radiation therapy to oligometastases in patients with oligometastatic hormone-sensitive prostate cancer. IV. In appropriate situations evaluate the feasibility and toxicities of using helical tomotherapy image-guided intensity-modulated radiation therapy (IMRT) to treat oligometastatic sites. OUTLINE: ANDROGEN DEPRIVATION THERAPY (ADT): Patients not currently on ADT receive goserelin acetate subcutaneously (SC) or leuprolide acetate via injection once every 4 or 12 weeks and bicalutamide orally (PO) once daily (QD). Treatment repeats every 12 weeks for up to 3 courses in the absence of disease progression or unacceptable toxicity. Patients already receiving ADT at the time of enrollment continue treatment until they have received 36 weeks of therapy. RADIATION THERAPY: Patients achieving PSA normalization after initiation of androgen deprivation therapy undergo intensity-modulated radiation therapy daily for 2-7 weeks during or after completion of androgen deprivation therapy. After completion of study treatment, patients are followed up every 4 weeks for 2 years, then every 3 months after year 2, and then every 6 months thereafter.