Biweekly administration of low-dose docetaxel in hormone-resistant prostate cancer: pilot study of an effective subtoxic therapy.

Taxane-based chemotherapy has shown activity but also toxicity when administered at standard doses in patients with hormone-resistant prostate cancer (HRPC). In this pilot study, we investigated biweekly low-dose docetaxel in patients with HRPC as a convenient regimen with low toxicity. Sixteen patients with metastatic HRPC entered the study. Median age was 73 years, median performance status (PS) was 2, and median Gleason score was 9. All patients had undergone and failed combined androgen-blockade therapy (luteinizing hormone-releasing hormone analogue plus antiandrogen) for their metastatic disease; 3 had also been treated with mitoxantrone. Treatment consisted of docetaxel 30 mg/m2 administered every 2 weeks. Prostate-specific antigen (PSA) response, characterized by a 50% decrease of PSA level confirmed 4 weeks later, was the primary endpoint. Durations of PSA response and toxicity assessment were secondary endpoints. A total of 136 biweekly docetaxel doses were administered, with a median of 8.5 doses per patient (range, 2-24). Six patients (38%; 95% confidence interval, 25%-43%) fulfilled the criteria of PSA response. Median duration of PSA response was 4.5 months (range, 3-12). Toxicity was negligible: myelotoxicity was practically absent, whereas 3 patients developed grade 1 alopecia and 1 patient developed dacryorrhea. We conclude that our study provides evidence that biweekly docetaxel at 30 mg/m2 can be considered an effective nontoxic therapeutic option for patients with HRPC. Confirmation of these preliminary data in larger-scale trials is justified