Paclitaxel and vinorelbine in anthracycline-pretreated breast cancer: a phase II study.

BACKGROUND Paclitaxel and vinorelbine are active in advanced breast cancer pretreated with anthracyclines We therefore conducted a phase II study to define the toxicity and activity of paclitaxel and vinorelbine administered in combination. PATIENTS AND METHODS Our patient population consisted of 37 patients with metastatic breast cancer, 35 of whom had received prior chemotherapy including anthracyclines. The treatment regimen included vinorelbine (25 mg/m2 i.v.) followed by paclitaxel (135 mg/m2 i.v. as a 3-hour infusion) on day 1; vinorelbine was repeated on day 8 in the first 14 patients and on day 3 in the remaining 23 patients. RESULTS Because of grade 4 neutropenia, the second dose of vinorelbine was reduced or omitted in 88% of the courses on the days 1 and 8 schedule and in 48% of the courses on the days 1 and 3 schedule. As a consequence the administered dose intensity of vinorelbine was significantly higher on the days 1 and 3 schedule (13 mg/m2/wk versus 8.3 mg/m2/ wk, P = 0.005). The overall response rate was 38% (95% CI: 22-55); four responses have been observed in the ten patients with absolute anthracycline resistance. The median duration of response was 6.5 months. CONCLUSIONS The combination of paclitaxel and vinorelbine is a feasible and active salvage regimen in advanced breast cancer patients pretreated with anthracyclines.