RATIONALE: Radiation therapy uses high-energy x-rays to kill tumor cells. Specialized radiation therapy that delivers a high dose of radiation directly to the tumor may kill more tumor cells and cause less damage to normal tissue. Androgens can cause the growth of prostate cancer cells. Androgen deprivation therapy, such as goserelin, leuprolide, or bicalutamide, may lessen the amount of androgens made by the body. Giving intensity-modulated radiation therapy together with androgen deprivation therapy may kill more tumor cells.