Salvage therapy with single-agent paclitaxel by three-hour infusion in metastatic breast cancer: an experience in Taipei Veterans General Hospital

Background: Paclitaxel is an active agent in the treatment of breast, ovari an, lung and head and neck cancers. In previous phase I and II trials, it e xerted novel cytotoxic effect on several malignancies. Various doses and re gimens of paclitaxel have been assessed in metastatic breast cancer, with r esponses between 20 and 62%. However, combination therapy with other anti-c ancer drugs leads to a high incidence of side effects. Our aim was to evalu ate the efficacy of paclitaxel given by 3 h infusion as salvage chemotherap y for patients with metastatic breast cancer. Methods: Between May 1999 and April 2000, 14 women with metastatic breast c ancer were enrolled in this study and all the patients had to have measurab le lesions. The median age of the patients was 48.7 years (range 39-56 year s). All of them were definitely evidenced as having metastatic breast cance r and received complete courses of anthracycline-containing agents before a pplying paclitaxel. The protocol was single-agent paclitaxel (Anzatax, Faul ding, Australia) at a moderate dosage of 175 mg/m(2) by 3 h intravenous inf usion every 3 weeks. Results: A total of 75 cycles were administered to these 14 patients with a median of four delivered cycles (range 3-14) and the response rate was 28. 6% (95% Cl: 21-40%), including four partial remission, three stable disease and seven progressive disease. The median time to progression was 3 (range 3-7) months. Hematological toxicities were minimal with no evidence of sev ere (grade 3 or 4) leukopenia and thrombocytopenia. Hepatic toxicities were observed in 12 cycles with five in grade 3. Conclusions: Our study indicates that utilizing single-agent paclitaxel exe rts moderate activity on anthracycline-refractory metastatic breast cancer patients without excessive toxicities.