Response to docetaxel/carboplatin-based chemotherapy as first- and second-line therapy in patients with metastatic hormone-refractory prostate cancer

OBJECTIVES: To evaluate the efficacy of docetaxel/carboplatin (DC)-based chemotherapy as first- and second-line chemotherapy for patients with hormone-refractory prostate cancer (HRPC). PATIENTS AND METHODS: We retrospectively identified all patients with HRPC treated with DC-based chemotherapy at the Dana-Farber Cancer Institute. Regimens either included estramustine (EDC) or not (DC). We identified patients who received EDC as first-line chemotherapy and patients who received DC as second-line or subsequent chemotherapy. Patients treated with EDC received 20-70 mg/m ² docetaxel every 1-4 weeks, estramustine 140 mg three times daily and carboplatin (area under the curve, AUC), (4-6) every 3-4 weeks. Patients treated with DC received docetaxel 50-70 mg/m² and carboplatin AUC (4-6) every 3-4 weeks. RESULTS: In all, the study included 54 patients; 24 received EDC and 30 DC (median age 62.8 and 66.9 years, respectively); their prostate-specific antigen (PSA) level at the start of chemotherapy was 112.7 and 213.3 ng/mL, respectively. There were declines of ≥50% in PSA level in 88% and 20% in the two groups, respectively. The median overall survival was 17.7 and 14.9 months in the EDC and DC groups, respectively. The most common reversible grade 4 toxicity with either regimen was neutropenia (4% and 7% in EDC and DC, respectively). CONCLUSIONS: DC-based chemotherapy is well tolerated and active in HRPC. Adding carboplatin to docetaxel provides an additional activity in 20% of patients as a second-line or subsequent chemotherapy.