Weekly administration of docetaxel in patients with hormone-refractory prostate cancer: a pilot study on Japanese patients

Objective: Although treatment of hormone-refractory prostate cancer (HRPC) is difficult, a single-agent weekly dose of docetaxel has been reported as a promising regimen for patients with HRPC. The purpose of this study was the investigation of the efficacy of docetaxel for Japanese patients with HRPC. Methods: Ten patients with HRPC were treated with weekly docetaxel at Tsukuba University Hospital and were evaluated for the responses with respect to serum prostate-specific antigen (PSA), tumor size and survival. Considering the ethnic balance, the dose of docetaxel was reduced to 30 mg/m(2) weekly compared with 36 mg/m(2) in the study reported previously. Results: A biochemical response (>50% decrease in PSA) was observed in five patients (56%; 5/9) with an average time to progression of 4.5 months. In two partial responders as determined by PSA, respective metastatic lesions in bone and soft tissue were also improved. The estimated median survival duration was 6 months. Most of these responses were accompanied by a significant reduction in the requirement for analgesic agents. No severe toxicity of this regimen was observed, except for gastric ulcer in one patient who was excluded from the evaluation. Conclusions: Weekly administration of docetaxel as a single agent was associated with a high rate of PSA reduction. This treatment is feasible for patients with HRPC, even those who have a poor performance status and extensive prior treatments.