DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of the prostate

• Intermediate risk for disease relapse as determined by any of the following combination of factors:

  • T1b-4, Gleason score 2-6, and prostate-specific antigen (PSA) greater than 10 but no greater than 100 ng/mL
  • T1b-4, Gleason score 7, and PSA less than 20 ng/mL
  • T1b-1c, Gleason score 8-10, and PSA less than 20 ng/mL
• Must have disease confirmation within 180 days of study randomization

• Clinically negative lymph nodes (N0) as established by imaging or negative lymph nodes by nodal sampling or dissection

  • Radiologic or radioimmunoscintigraphy findings suggestive of regional nodal involvement allowed provided cytologic or histologic evaluation shows no evidence of a neoplastic process
  • Equivocal radiologic findings (i.e., maximum nodal size no greater than 1.5 cm) allowed

• No distant metastases (M0)

  • Radionuclide imaging findings suggestive but not diagnostic of metastatic disease allowed provided radiologic imaging does not confirm metastatic disease

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• Zubrod 0 or 1

Life expectancy:

• At least 10 years

Hematopoietic:

• Not specified

Hepatic:

• ALT no greater than 2 times upper limit of normal

Renal:

• Not specified

Other:

• Fertile patients must use effective contraception
• No other concurrent medical illness that would result in a life expectancy of less than 10 years
• No other invasive malignancy within the past 5 years except localized basal cell or squamous cell skin cancer
• No other concurrent major medical or psychiatric illness that would preclude study treatment or follow-up

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Not specified

Chemotherapy:

• No prior chemotherapy for prostate cancer

Endocrine therapy:

• No prior androgen-deprivation therapy except luteinizing hormone-releasing hormone (LHRH) agonist AND bicalutamide OR flutamide provided:

  • LHRH agonist was initiated no more than 30 days before study randomization and bicalutamide OR flutamide was initiated no more than 14 days before or after LHRH agonist administration
• No concurrent finasteride for prostatic hypertrophy

Radiotherapy:

• No prior pelvic external beam radiotherapy
• No prior radionuclide prostate brachytherapy
• No concurrent intensity-modulated radiotherapy

Surgery:

• No prior prostatectomy
• No prior prostatic cryosurgery
• No prior bilateral orchiectomy

Other:

• No other concurrent medical research study involving prostate cancer treatment