Weekly paclitaxel with epirubicin as second-line therapy of metastatic breast cancer: results of a clinical phase II study.

Phase I/II trials have shown that combination of an anthracycline with paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) represents a high-potency therapy for treatment of patients with metastatic breast cancer, with response rates exceeding 90%. This phase II trial was conducted to test the tolerability and efficacy of weekly epirubicin plus paclitaxel as second-line therapy for patients with pretreated metastatic breast cancer. In this study, 35 patients with previous hormone therapy and/or chemotherapy were treated at a weekly dose of paclitaxel 80 mg/m2 with epirubicin 35 mg/m2 (10 patients, 123 cycles) or paclitaxel 80 mg/m2 with epirubicin 25 mg/m2 (25 patients, 218 cycles). The dose reduction of anthracyclines became necessary due to severe hemotoxicity (neutropenia World Health Organization grade 3 to 4 in 30.2% of cycles). The therapy schema included a 2-week therapy interval after each treatment period of 6 weeks, with treatment continued until response or disease progression. Overall, 18 patents (51.4%) presented with responses (complete response or partial response) to therapy, with seven (20%) achieving a complete response after six to 18 cycles. In three cases (8.6%), tumor state was unchanged for a median interval of 11 weeks (range, 5 to 20 weeks). Progressive disease was observed in seven cases (20%), and seven patients (20%) were not evaluable. Following epirubicin dose reduction, neutropenia World Health Organization grade 3 to 4 occurred in only 18.1% of cycles. Referring to nonhematologic toxicity, alopecia exceeded World Health Organization grade 2. Other nonhematologic toxicities exceeding grade 2 were observed in only a few courses and were not statistically relevant. No clinically relevant deterioration of cardiac function was observed at a median cumulative dose of epirubicin 285 mg/m2 (maximum cumulative dose, 630 mg/m2). This study has substantiated that the schedule used is highly efficient and well tolerated as second-line chemotherapy for patients with metastatic breast cancer.