Summary
This randomized phase III trial studies how well stereotactic body radiation therapy works compared to intensity-modulated radiation therapy in treating patients with stage IIA-B prostate cancer. Radiation therapy uses high energy x-rays to kill tumor cells and shrink tumors. Stereotactic body radiation therapy uses special equipment to position a patient and deliver radiation to tumors with high precision. This method can kill tumor cells with fewer doses over a shorter period and cause less damage to normal tissue. Stereotactic body radiation therapy may work better in treating patients with prostate cancer.