Weekly docetaxel/paclitaxel in pretreated metastatic breast cancer

Abstract

The purpose of our study was to evaluate the feasibility and efficacy of weekly docetaxel/paclitaxel in pretreated advanced breast cancer patients. Twenty-six patients with metastatic breast cancer were included in this study. Three different schedules of treatment were administered. The starting schedule, A1, consisted of docetaxel 60 mg/m2 on day 1 plus paclitaxel 60 mg/m2 over 1 hour, weekly for 18 weeks; this schedule was considered feasible if at least 70% of the planned doses were given on time and without reduction. Schedule A2 consisted of the same doses administered on days 1 and 8 every 3 weeks, and schedule B consisted of docetaxel 25 mg/m2 followed by paclitaxel 40 mg/m2 for 1 hour on days 1 and 8 every 3 weeks for a total of 6 cycles. All patients had received prior anthracyclines, and 19 patients were pretreated with taxanes. Seventy-seven percent of patients had received at least 2 prior lines of chemotherapy. Twenty-five patients are assessable for toxicity and efficacy. A total of 109 cycles of chemotherapy have been administered, with a median of 4 cycles per patient (range, 1-8 cycles). The median delivered dose intensity was 27 mg/m2/week for paclitaxel (range, 18-50 mg/m2/week) and 17 mg/m2/week (range, 12-39 mg/m2/week) for docetaxel. Six patients received schedule A1. This schedule was considered not feasible due to neutropenia grade > 2, mucositis, and diarrhea grade 2, which required dose reduction/omission in 33% of administrations. For this reason, treatment in the following 5 patients was omitted on day 15 (schedule A2). Schedule B was found to be more feasible with 16% of dose reductions/omissions. The overall response rate was 68% (95% CI, 50%-86%) with a median duration of response of 10 months (range, 2-18+ months). Treatment was well tolerated; myelosuppression was rare and grade 3 cutaneous toxicity was observed in only 2 patients. In conclusion, weekly docetaxel/paclitaxel is active at low dosages and was well tolerated as salvage chemotherapy in metastatic breast cancer. This regimen represents a valid option as a salvage treatment in taxane- and anthracycline-pretreated patients.