PSA Levels and Biopsy Samples After Implant Radiation and Hormone Therapy in Patients With Stage I or Stage II Prostate Cancer

DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed prostate cancer * Previously untreated disease prior to participation on protocol JUSMH-BRI-GU05-01 * Intermediate-risk disease as defined by the following: * Clinical stage \< T2c * Prostate-specific antigen (PSA) ≤ 20 ng/mL * Gleason score \< 8 * Previously enrolled on protocol JUSMH-BRI-GU05-01 PATIENT CHARACTERISTICS: * ECOG performance status 0-1 * Life expectancy ≥ 3 months * WBC ≥ 2,000/μL * Hemoglobin ≥ 10.0 g/dL * Platelet count ≥ 100,000/μL * Serum creatine level ≤ 2.0 mg/dL * ALT and AST ≤ 100 IU/L * No other cancer requiring treatment * No poorly controlled hypertension (i.e., diastolic blood pressure ≥ 120 mm Hg) * No severe psychiatric disorders, including schizophrenia or dementia * No poorly controlled diabetes * Considered appropriate for study participation, as determined by the Principal Investigator or Clinical Investigator PRIOR CONCURRENT THERAPY: * No prior drugs for benign prostatic hyperplasia (other than antiandrogen therapy) * No prior surgery for prostate cancer * No concurrent steroid drugs (except for ointment) * No other concurrent antiandrogen therapy