DISEASE CHARACTERISTICS: Histologically proven locally recurrent organ-confined prostate cancer after external beam radiotherapy, radiation seed implants, or cryosurgery. Gleason score of at least 6. Prostate specific antigen values (PSA) of at least 1.0 ng/mL with 2 consecutive rises in PSA at least 2 weeks apart, of which the second increase is greater than the first, after achieving a nadir. Must have at least 3 recorded PSA values over a minimum of the last 3 months to determine the slope. Patients must have declined additional conventional treatment or be ineligible for conventional treatment of their prostate cancer. No metastasis by bone scan. No significant central nervous system (CNS) disease.