Inclusion criteria:

* Histologically confirmed locally confined adenocarcinoma of the prostate with primary tumors confined to the prostate, clinical stage T1b,1c, 2a or 2b.
* Negative nodes evaluated by imaging methods (classified in the study as NX) or by surgical sampling (classified in the study as N0).
* Karnofsky performance status ≥ 70.
* PSA is mandatory, must be ≤ 20)
* No prior hormonal therapy, radiation or chemotherapy.
* Prior finasteride for prostate hypertrophy allowed if discontinued at least 60 days prior to randomization.
* Prior testosterone administration allowed if at least 90 days elapsed since last administration.
* No evidence of distant metastasis or other synchronous primary. Patients with prior invasive malignancy who were disease free for at least 5 years could be eligible with pre-randomization approval by the study chairman.
* Treatment begins within 21 days after randomization.
* Patients signs a study-specific informed consent form.
* Alanine Aminotransferase (ALT) within 2x upper normal limits.

Exclusion criteria:

* Stage T1a or ≥ T2c disease.
* Lymph node involvement (N1 - N3).
* Evidence of distant metastasis. (M1)
* PSA \> 20.
* Radical surgery or cryosurgery for carcinoma of the prostate, previous irradiation, antiandrogen therapy or chemotherapy.
* Previous or concurrent cancers other than basal cell or squamous cell skin carcinoma.

Patients with squamous cell carcinomas required to be NED (no evidence of disease) for a minimum of two years prior to study entry.

* Major medical or psychiatric illness which, in the investigator's opinion, would prevent completion of treatment and would interfere with follow-up.
* Karnofsky performance status of \< 70.