Docetaxel and Prednisone in Treating Patients With Hormone-Refractory Metastatic Prostate Cancer

DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed adenocarcinoma of the prostate * Metastatic disease by imaging or clinical examination * Hormone-refractory disease, defined as prostate-specific antigen (PSA) level \> 10 µg/L AND rising between 2 sequential measurements * Testosterone within castration levels by orchiectomy or medical castration comprising luteinizing hormone-releasing hormone (LHRH) analogues PATIENT CHARACTERISTICS: Age * Over 18 Performance status * WHO 0-2 Life expectancy * Not specified Hematopoietic * Neutrophil count ≥ 1,500/mm\^3 * Hemoglobin ≥ 11.0 g/dL * Platelet count ≥ 100,000/mm\^3 Hepatic * ALT and AST ≤ 2.5 times upper limit of normal (ULN) * Bilirubin normal * Alkaline phosphatase ≤ 6 times ULN (unless due to the presence of extensive bone disease) * No serious liver disease Renal * Creatinine ≤ 1.5 times ULN Cardiovascular * No ischemic or thromboembolic cardiac disease * No myocardial infarction within the past 12 months * No other serious cardiac disease Pulmonary * No pulmonary emboli Immunologic * No active infection * No autoimmune disease, including any of the following: * Lupus * Scleroderma * Rheumatoid polyarthritis Other * No active peptic ulcer * No unstable diabetes mellitus * No contraindication to corticosteroids * No other malignant disease within the past 5 years except basalioma * No functional iron deficiency (i.e., transferrin saturation \< 20%) that cannot be treated with iron supplementation * No other serious illness or medical condition PRIOR CONCURRENT THERAPY: Biologic therapy * More than 2 months since prior recombinant human epoetin alfa or any other erythropoiesis-stimulating drug Chemotherapy * At least 3 weeks since prior estramustine Endocrine therapy * See Disease Characteristics * At least 3 weeks since prior antiandrogen treatment * Concurrent chemical castration with LHRH allowed provided patient has begun treatment prior to study entry * No initiation of chemical castration therapy during study treatment Radiotherapy * No prior radiotherapy to \> 25% of bone marrow * No prior radioisotope therapy * Concurrent local palliative radiotherapy for pain allowed Surgery * See Disease Characteristics * At least 4 weeks since prior surgery Other * No other prior cytostatic treatment * Concurrent bisphosphonates allowed provided patient has begun treatment prior to study entry * No initiation of bisphosphonates during study treatment