TRUEBEAM Stereotactic Body Radiotherapy for Localized Prostate Cancer

Inclusion Criteria 1. Histologically proven prostate adenocarcinoma * Biopsy within 12 months of date of registration required except for patients who already meet criteria for enrollment in the high risk arm of the protocol. For these patients, repeat biopsy will be at the discretion of the treating physician. In general, repeat biopsy is recommended for these patients, but is not required if it will not affect the treating physician's management decisions in regards to the care of the patient. 2. Clinical Stage I-IV, MX-M0 (AJCC 6th Edition) * M-stage determined by physical exam, CT, MRI, or Bone Scan. Bone scan not required for Monotherapy Risk Group patients unless clinical findings suggest possible osseous metastases. Bone Scan and contrast CT of the abdomen should be done patients in the Boost Risk Group patients. 3. Prostate volume: ≤ 100 cc (recommended not required) * Determined using: volume = π/6 x length x height x width * Measurement from CT or ultrasound ≤90 days prior to registration. 4. ECOG performance status 0-1 5. Completion of patient questionnaires in section 4.7. 6. Consent signed Exclusion Criteria: 1. Prior prostatectomy or cryotherapy of the prostate 2. Prior radiotherapy to the prostate or lower pelvis 3. Implanted hardware or other material that would prohibit appropriate treatment planning or treatment delivery, in the investigator's opinion.