Inclusion Criteria:  Intermediate-risk prostate cancer patients will be eligible for this study. Risk groups will be assigned as per NCCN guidelines. Intermediate-risk patients will be defined as:  PSA 10-20 ng/ml or Gleason score = 7 Clinical stage T2b/T2c  Additionally, patients will be required to meet all of the following criteria:  Age ≥ 18 Karnofsky Performance Status (KPS) ≥ 80 (Appendix 1) Prostate size ≤ 80 cc Presence of a T2-visible prostatic lesion with maximum dimension of ≥ 0.5 cm and no more than one additional disease focus MRI findings: Lesion may contact the capsular edge, possible extracapsular extension (ECE) permitted International Prostate Symptom Score ≤ 15 Satisfy all MRI screening criteria and be willing to fill out the standard MRI screening form  Exclusion Criteria:  Patient will be excluded if they meet any one of the following criteria:  Gleason score >7 PSA >20 Prior or concurrent androgen deprivation therapy for prostate cancer MRI findings: suspicious for/probable ECE MRI findings: >2 disease foci identifiable Evidence of metastatic disease on bone scan or MRI/CT MRI ineligibility due to: the presence of a cardiac pacemaker, defibrillator, or other implanted metallic or electronic device which is considered MR unsafe; severe claustrophobia; inability to lie flat for the duration of the study; etc. Metallic implant or device in the pelvis that might distort the local magnetic field and compromise quality of mp-MRI Lateral pelvic separation greater than 50 cm and/or anterior-posterior separation greater than 35 cm which are incompatible with MRCAT reconstruction Contra-indications to receiving gadolinium contrast KPS < 80 Pelvic MRI or CT (MRI preferred) evidence of radiographic T3, T4, or N1 disease Prior history of transurethral resection of the prostate Prior history of urethral stricture Prior history of pelvic irradiation History of inflammatory bowel disease Unable to give informed consent Unable to complete quality of life questionnaires  Abnormal complete blood count, including any of the following:  Platelet count less than 75,000/ml Hb level less than 10 gm/dl WBC less than 3.5/ml Abnormal renal function tests (creatinine > 1.5)