Multicenter phase II trial of weekly paclitaxel for advanced or metastatic breast cancer: the Saitama Breast Cancer Clinical Study Group (SBCCSG-01)

Objective: Weekly dosing of paclitaxel has been demonstrated to be a well-tolerated, feasible and effective administration schedule. In this study, we evaluated the efficacy and safety of weekly paclitaxel in Japanese women with advanced or metastatic breast cancer. Methods: Seventy-four patients were enrolled in the study. Paclitaxel was administered by 1 h intravenous infusion at a dose of 80 mg/m(2) every week. Administration was continued for 3 weeks followed by a 1 week rest. A short premedication, consisting of dexamethasone 10 mg, ranitidine 50 mg and diphenylhydramine 50 mg, was given prior to each dose of paclitaxel. Eligibility criteria included an Eastern Cooperative Oncology Group performance status of 0, 1 or 2 and adequate hematological, hepatic and renal function. Results: Of 74 patients treated and evaluable for toxicities, 70 were evaluable for response. The mean age was 57.7 years. Forty-nine patients (66.2%) had received prior anthracyclines for metastatic diseases. The overall response rate among 74 patients was 40.5%, including 4.1% complete responses and 36.5% partial responses. The median follow-up time was 481 days (range, 24-903 days). The median time to progression was 4.8 months and median overall survival was 15.8 months. The majority of patients tolerated the treatment very well. Although alopecia was observed in most of the patients (93.2%), grade 3 or 4 neutropenia was 10.8% and grade 2 or 3 peripheral neuropathy was 13.5%. Conclusion: Weekly paclitaxel as a 1 h infusion was active and generally well tolerated in previously treated patients. Further study of weekly paclitaxel in combination therapy is warranted.