Background: Paclitaxel has shown activity in metastatic breast cancer, including anthracycline-resistant breast cancer. The efficacy, toxicity and optimal scheduling of the combination of the two drugs needs to be defined.
Patients and methods: Thirty women with advanced breast cancer who had undergone at most one prior adjuvant chemotherapy regimen, were treated at three different dose levels with doxorubicin (50, 60 and 60 mg/m2) followed 30 minutes later by paclitaxel (155, 175 and 200 mg/m2, respectively) every 3 weeks.
Results: The overall response rate was 83% (95% CI: 64-94), with 24% of patients achieving CR. The median response duration for complete responders was 11 months (range 4-14+) and median survival 18 months (range 3-28+). Two hundred sixty-five treatment courses were given (median 9, range 3-13) and the median cumulative dose of doxorubicin was 369 mg/m2 (range 114-550). The main toxicities were neutropenia, parestesia, nausea/vomiting, alopecia, myalgia and cardiotoxicity. Fifteen patients (50%) had reductions of left ventricular ejection fraction of below normal levels and 6 of these patients (20%) developed congestive heart failure.
Conclusion: The combination of doxorubicin and paclitaxel is highly active, but is accompanied by the dose-limiting toxic effects of neutropenia, neuropathy and cardiotoxicity.