ZANTE: Zometa and Taxotere in Hormone Refractory Prostate Cancer

Inclusion Criteria: * Written informed consent * Hormone refractory prostate cancer * Stage IV disease with bone metastasis * No immunotherapy, hormonal therapy or radiotherapy within the previous month * Performance status \< or = 2 (ECOG) * Serum creatinine \< 1.5 mg/100ml * Serum bilirubin \< or = 1.25 x UNL (upper normal limit) (or \< or = 1.5 x UNL in the presence of hepatic metastases); SGOT e SGPT \< or = 1.5 x UNL (or \< or = 2.5 x UNL in presence of hepatic metastases) * Left ventricular ejection fraction \> or = 50% (measured by cardiac ultrasound or MUGA scan) * Neutrophils \> 1500/mm3; platelets \>100000/mm3; hemoglobin \>10 g/100 ml· Life expectancy of at least 3 months Exclusion Criteria: * Previous malignancies with the exception of radically treated epithelioma * Previous chemotherapy * Comorbidities that would, in the Investigator's opinion, contraindicate the use of the drugs in the study * Uncontrolled Diabetes * Severe cardiac arrhythmias, severe uncontrolled congestive heart failure, severe ischemic cardiac disease or myocardial infarction within the previous 6 months * severe infection * cerebral metastasis * Pre-existing motor or sensory neurotoxicity \> or = grade 2 according to CTC (Common Toxicity Criteria).