DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of the prostate

  • Metastatic disease (e.g., bone, pelvic mass, nodal, liver, or lung metastases) with evidence of disease progression by radiography (including bone scans observed during last treatment) or serology

    • Patients with bone-only metastases (i.e., lacking soft tissue or visceral disease) must have a prostate-specific antigen (PSA) level ≥ 10 ng/mL
    • Patients with soft tissue metastases and/or visceral disease must have measurable disease OR PSA ≥ 10 ng/mL

• Underwent prior bilateral orchiectomy or other primary hormonal therapy (e.g., luteinizing hormone-releasing hormone [LHRH] therapy or estrogen) with subsequent evidence of treatment failure and simultaneous documentation of a castrate testosterone level ≤ 50 ng/dL

  • Patients who have not undergone bilateral orchiectomy must continue LHRH agonist therapy throughout study treatment unless medically contraindicated
• Prior therapy with docetaxel alone or in combination with either prednisone or estramustine phosphate sodium required in a neoadjuvant, adjuvant, or metastatic setting
• No brain metastases or carcinomatous meningitis

PATIENT CHARACTERISTICS:

• ECOG performance status 0-1
• ANC ≥ 1,200/mm^3
• Hemoglobin ≥ 9.0 g/dL
• Platelet count ≥ 100,000/mm^3
• Creatinine ≤ 2.0 mg/dL
• Bilirubin < 2.5 mg/dL
• AST and ALT ≤ 2.5 times upper limit of normal (ULN) (≤ 5 times ULN for patients with hepatic metastases)
• Fertile patients must use effective contraception during and for up to 3 months after completion of study therapy
• Prior malignancy allowed provided patient was treated with curative intent and is free of disease for the time period considered appropriate for the specific malignancy
• At least 6 months since prior myocardial infarction, New York Heart Association (NYHA) class III congestive cardiac failure, or coronary angioplasty/stenting
• No active angina pectoris, uncontrolled hypertension, or NYHA class IV heart disease
• No concurrent serious medical illness or active infection that would preclude study therapy
• No allergy to sulfa medications
• No neurology findings > grade 1

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics
• Recovered from all prior therapy (not including incontinence or impotence secondary to primary therapy)

• More than 3 weeks since prior radiotherapy

  • If patient has received prior radiotherapy to evaluable lesions, there must be evidence of radiographic progression prior to study entry
• At least 4 weeks since prior flutamide or nilutamide (6 weeks for bicalutamide) with no evidence of an antiandrogen withdrawal response (i.e., no decline in serum PSA and/or no improvement in baseline scans)
• More than 4 weeks since prior and no other concurrent investigational agents
• No more than 1 prior chemotherapy regimen
• No prior strontium chloride Sr 89, samarium Sm 153 lexidronam pentasodium, or other therapeutic radioisotopes
• Concurrent bisphosphonate therapy allowed provided therapy was initiated at least 4 weeks prior to study entry
• No concurrent colchicines
• No other concurrent anticancer therapy