Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically confirmed adenocarcinoma of the prostate

- Stage D1 or D2 disease (T4, N0, M0; any T, N1-3, M0; or any T, any N, M1)

- Unresponsive or refractory to prior hormonal therapy by at least 1 of the following:

- Progression of unidimensionally measurable lesion outside of a prior radiation
port

- Progression of non-measurable disease (e.g., bone scan)

- Rising prostate-specific antigen (PSA) on at least 2 consecutive measurements taken
at least 7 days apart

- PSA at least 5 ng/mL

- No brain metastases

PATIENT CHARACTERISTICS:

Age:

- Not specified

Performance status:

- Zubrod 0-2

Life expectancy:

- Not specified

Hematopoietic:

- Absolute granulocyte count at least 1,500/mm^3

- Platelet count at least 100,000/mm^3

Hepatic:

- Bilirubin no greater than upper limit of normal (ULN)

- SGOT or SGPT no greater than 2.5 times ULN

Renal:

- Creatinine no greater than 2.0 mg/dL OR

- Creatinine clearance at least 40 mL/min

Other:

- No other malignancy within the past 5 years except adequately treated squamous cell
or basal cell skin cancer, any carcinoma in situ, or stage I or II cancer in complete
remission

- No other concurrent significant active illness that would preclude study
participation

- Recovered from major infections

- Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

- At least 28 days since prior biologic therapy and recovered

- No more than 1 prior biologic (non-cytotoxic) therapy

- No concurrent biological response modifiers

Chemotherapy:

- No prior chemotherapy for this disease

- No other concurrent chemotherapy

Endocrine therapy:

- See Disease Characteristics

- At least 28 days since prior flutamide or ketoconazole

- At least 42 days since prior bicalutamide or nilutamide

- No concurrent hormonal therapy, except luteinizing hormone-releasing hormone therapy

- No concurrent corticosteroids

Radiotherapy:

- See Disease Characteristics

- Prior radiotherapy to less than 30% of bone marrow allowed

- No prior strontium chloride Sr 89 or samarium Sm 153 lexidronam pentasodium

- At least 28 days since prior radiotherapy and recovered

- No concurrent radiotherapy

Surgery:

- Recovered from prior surgery

- Prior orchiectomy allowed

Other:

- No concurrent unconventional therapy (e.g., St. John's Wort, PC-SPES, or other herbal
remedy for prostate cancer)

- Not planning to begin bisphosphonate therapy (patients already receiving
bisphosphonates are eligible provided they have progressive disease)