participants are no longer being followed up.

RATIONALE: 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.

PURPOSE: This clinical trial is studying how well proton radiation therapy works in treating patients with prostate cancer.

Detailed Description

PRIMARY OBJECTIVES:

I. Feasibility of proton radiation therapy (RT) using standard fractionation.

SECONDARY OBJECTIVES:

I. To determine freedom from failure (FFF) (vs. biochemical/clinical progression-free survival) with standard fractionation.

II. To determine the incidence of grade 2 or greater GU and GI toxicity with this regimen at 6 months, 2 years and 3 years.

III. To assess quality of life issues following completion of radiation therapy at 6 months and at 2 years.

IV. To assess incidence of impotence after the use of proton therapy at 3 years.

V. To determine freedom from biochemical failure (BF) at 5 years.

VI. To determine clinical failure: local and/or distant at 5 years. VII. To determine salvage androgen deprivation (SAD) use at 5 years. VIII. To determine progression free survival: using clinical, biochemical and SAD as events at 5 years.

IX. To determine overall survival at 5 years. X. To determine disease-specific survival at 5 years.

XI. Estimate prostate and normal structures movement during RT with the use of scans.

XII. Correlate pathologic and radiologic findings with outcomes at 5 years. XIII. Correlate PSA and free PSA levels with outcomes at 5 years. XIV. Correlate testosterone levels and variation with proton therapy and outcomes at 5 years.

XV. Develop a quality assurance process for proton prostate therapy.

OUTLINE:

Patients undergo proton radiotherapy once daily 5 days a week for approximately 9 weeks in the absence of disease progression or unacceptable toxicity.

After completion of study treatment, patients are followed at 3 months, every 6 months for 5 years, and then annually thereafter.

Inclusion Criteria:

• Histologically confirmed prostate adenocarcinoma within 365 days of registration
• Clinical stages T1a-T2a N0 M0
• For any pelvic lymph node >= 1.5cm, biopsy of the lymph node is mandatory
• Histological evaluation of prostate biopsy with assignment of a Gleason score to the biopsy material; Gleason score must be in the range 2-6; > 6 cores is strongly recommended; the highest Gleason score in any core reported on the pathology report will be used for determining inclusion
• PSA values < 10 ng/ml within 90 days prior to registration, done either prior to prostate biopsy or at least 21 days after prostate biopsy.
• Alkaline phosphatase within 60 days prior to registration. If alkaline phosphatase is elevated > 2 x the upper limit of institutional normal (UNL), patient must have radiological correlation to assess for metastases
• Zubrod status 0-1 documented within 60 days of registration
• Prior androgen deprivation is allowed; however, androgen deprivation will not be continued concurrently or as an adjuvant therapy
• Patients must give IRB-approved study-specific informed consent
• Patients must complete all required tests listed within the specified time frames
• Patients must be able to start treatment within 56 days of registration
• Members of all races and ethnic groups are eligible for this trial

Exclusion Criteria:

• Clinical stages T2c or greater
• PSA of 10 ng/ml or greater
• Gleason score 7 or higher
• Evidence of distant metastasis
• Evidence of lymph node involvement
• Previous prostate cancer surgery to include: prostatectomy, hyperthermia and cryosurgery
• Previous pelvic radiation for prostate cancer
• Androgen deprivation therapy prior to radiation is allowed; however, it is not acceptable if continued during radiation or as adjuvant therapy
• Active rectal diverticulitis, Crohn's disease, or ulcerative colitis are not allowed
• Prior systemic chemotherapy for prostate cancer
• History of proximal urethral stricture requiring dilatation