Inclusion Criteria

DISEASE CHARACTERISTICS: Hormone refractory metastatic prostate cancer (stage D1 or D2)
with no greater than 3 prior endocrine manipulations PSA level increased on 3 consecutive
measurements at least 2 weeks apart PSA at least 10 ng/mL (not required if measurable
disease)

PATIENT CHARACTERISTICS: Age: Not specified Performance status: SWOG 0-2 Life expectancy:
At least 12 weeks Hematopoietic: Granulocyte count at least 1,500/mm3 Hemoglobin at least
8 g/dL Platelet count at least 100,000/mm3 Hepatic: Bilirubin less than 2 mg/dL AST no
greater than 2 times upper limit of normal Renal: Creatinine less than 2.0 mg/dL Other: No
other serious medical illness No serious infection No other prior malignancy within the
past 5 years except nonmelanoma skin cancer or any in situ carcinoma

PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: No prior
chemotherapy Endocrine therapy: See Disease Characteristics Concurrent LHRH-agonist
therapy allowed without antiandrogens At least 4 weeks since prior flutamide and
nilutamide At least 6 weeks since prior bicalutamide At least 4 weeks since other prior
hormone therapy including steroids Radiotherapy: At least 4 weeks since prior radiation
therapy and recovered No prior strontium Surgery: Recovered from prior surgery