CyberKnife Radiosurgery for Localized Prostatic Carcinoma

Eligibility Details: Inclusion Criteria: - Histologically confirmed adenocarcinoma of the prostate, clinical stage T1b - T2b (AJCC 6th Edition, see Appendix II), NX/N0, M0. - Karnofsky performance status > 80. - Patient must be ≥ 18 years of age. - Gleason Sum < or = 7 - Prostate-specific antigen < or = 20 ng/ml - Patients must sign a study-specific informed consent form prior to study entry. Exclusion Criteria: - Stage < T1b, T2c, T3 or T4 disease (AJCC 6th Edition, see Appendix II). - Gleason Score > 7. - PSA > 20 ng/ml. - Lymph node involvement (N1). - Evidence of distant metastases (M1). - Radical surgery for carcinoma of the prostate, prior pelvic radiation, pelvic surgical clips or other metallic foreign bodies. - History of hormonal therapy (antiandrogen or 5 alpha reductase treatment within three months prior to treatment). - Previous or concurrent cancers other than basal, in situ, or squamous cell skin cancers unless disease-free for ≥ 5 years. - Major medical or psychiatric illness, which in the investigator's opinion, would prevent completion of treatment and would interfere with follow-up. - Metallic Hip prosthesis. - History of inflammatory bowel disease