Combination chemotherapy with weekly paclitaxel or docetaxel, carboplatin, and estramustine for hormone-refractory prostate cancer

Paclitaxel (PTX) and docetaxel (DTX) have been reported to be effective for treating hormone-refractory prostate cancer (HRPC). The objective of this study was to examine the efficacy of weekly DTX (PTX)-based chemotherapy and compare weekly DTX-based chemotherapy with triweekly (once every 3 weeks) DTX-based chemotherapy. We performed a combination chemotherapy on a weekly cycle with an i.v. PTX 100 mg/m² or i.v. DTX 30 mg/m² (days 1, 8, 15, and 22), i.v. carboplatin (CBDCA) (day 1, area under the plasma concentration time curve = 6), and oral estramustine phosphate 10 mg/kg daily for 10 HRPC patients. In addition, we investigated the patient characteristics and treatment efficacy and toxicity. Among all cases, serum prostate-specific antigen (PSA) decreased by 50% or more in 90% of patients, by 75% or more in 70%, and 90% or more in 40% after chemotherapy. The effectiveness of weekly DTX-based chemotherapy was comparable with previous reports, and we showed no toxicity serious enough to require cancellation of chemotherapy. In conclusion, weekly DTX-based chemotherapy was no less effective and less toxic than triweekly DTX-based chemotherapy for HRPC patients and therefore can be useful as the first-line chemotherapy regimen for HRPC patients, especially the elderly or those with a poor performance status.