Radiation Therapy in Treating Patients With Stage II or Stage III Prostate Cancer

DISEASE CHARACTERISTICS: Previously untreated adenocarcinoma of the prostate T1b-c or T2a-b with a Gleason score more than 5 and PSA greater than 4 ng/mL OR Any T3 PSA under 70 ng/mL within 3 weeks prior to entry and at least 10 days after prostate biopsy No biopsy proven regional nodal involvement No distant metastases PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Karnofsky 80-100% Hematopoietic: White blood cell (WBC) count of at least 4,000/mm3 Platelet count at least 100,000/mm3 Hemoglobin at least 11 g/dL Hepatic: Not specified Renal: Not specified Other: No major medical or psychiatric illness that would preclude study No other malignancy within the past 5 years PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: No prior or concurrent chemotherapy Endocrine therapy: Prior hormonal therapy allowed Radiotherapy: No prior pelvic irradiation Surgery: No prior prostatectomy or cryosurgery for prostate cancer