DISEASE CHARACTERISTICS:

• Diagnosis of hormone-refractory metastatic prostate cancer by one of the following methods:

  • Measurable disease
  • PSA level of at least 5 ng/mL with a positive bone scan

• Objective evidence of progressive metastatic disease in the past 3 months defined by any of the following:

  • An increase in PSA value of at least 25% (minimum absolute increase of 5 ng/mL) on at least 2 successive occasions, at least 2 weeks apart
  • A new symptomatic lesion on bone scan
  • A new metastases not in bone
  • Growth of existing non-bone measurable metastatic disease NOTE: An increase in pain or symptoms alone without other evidence of progression, or elevation of PSA or serum alkaline phosphatase alone without evidence of metastatic disease is not sufficient

• Prior bilateral orchiectomy or other primary hormonal treatment with evidence of treatment failure

  • Patients with no prior bilateral orchiectomy must have a testosterone level less than 50 ng/mL and must continue leuteinizing hormone-releasing hormone therapy while on study
• No known active CNS metastases (excluding prior CNS metastases with currently stable disease after treatment )

PATIENT CHARACTERISTICS:

Age

• 18 and over

Performance status

• ECOG 0-2

Life expectancy

• More than 3 months

Hematopoietic

• WBC at least 3,000/mm^3
• Absolute neutrophil count at least 1,500/mm^3
• Platelet count at least 100,000/mm^3
• Hemoglobin at least 10 g/dL (transfusion allowed)

Hepatic

• Bilirubin no greater than 2.0 mg/dL
• ALT/AST no greater than 5 times upper limit of normal
• Albumin greater than 2.5 g/dL
• Chronic hepatitis allowed

Renal

• Creatinine no greater than 2.0 mg/dL

Cardiovascular

• No myocardial infarction within the past 3 months
• No unstable angina
• No uncontrolled arrhythmias
• No uncontrolled congestive heart failure

Pulmonary

• No dyspnea at rest

Other

• Nutrition adequate (caloric intake considered adequate for maintenance of weight)
• Fertile patients must use effective contraception
• No prior or concurrent malignancies except for non-metastatic basal cell or squamous cell skin cancer or any stage I malignancy curatively resected more than 5 years ago
• No active uncontrolled infectious process
• No other life-threatening illness
• No peripheral neuropathy greater than grade 2

PRIOR CONCURRENT THERAPY:

Biologic therapy

• At least 2 weeks since prior biologic therapy

Chemotherapy

• At least 3 weeks since prior chemotherapy (6 weeks for nitrosoureas or mitomycin) and recovered
• No more than 1 prior chemotherapy regimen for metastatic disease

Endocrine therapy

• See Disease Characteristics

• At least 4 weeks since other prior hormonal therapy including any of the following:

  • Megestrol
  • Finasteride
  • Herbal products known to decrease PSA levels (e.g., saw palmetto and PC-SPES)
  • Systemic corticosteroids
• At least 4 weeks since prior flutamide therapy (6 weeks for bicalutamide or nilutamide) with continued evidence of progressive disease documented by at least 1 PSA value after discontinuation

Radiotherapy

• At least 8 weeks since prior radiopharmaceuticals (strontium chloride Sr 89, samarium Sm 153 lexidronam pentasodium)
• At least 4 weeks since prior radiotherapy and recovered

Surgery

• See Disease Characteristics
• At least 3 weeks since prior major surgery and recovered

Other

• No other concurrent investigational agents
• No other concurrent anticancer treatment