A phase II trial of weekly paclitaxel, 5-fluorouracil, and leucovorin as first-line treatment for metastatic breast cancer

Purpose. This phase II multicenter trial evaluated the efficacy and toxicity of weekly paclitaxel, 5-fluorouracil, and leucovorin administered as first-line therapy for metastatic breast cancer. Patients and methods. The study enrolled 155 women with pathologically confirmed and measurable metastatic adenocarcinoma of the breast. Treatment consisted of paclitaxel 80 mg/m(2), 5-fluorouracil 425 mg/m(2), and leucovorin 20 mg/m(2) administered weekly 4 x per 4-week cycle in the first 40 patients enrolled ( group 1), and weekly 3 x per 4-week cycle in the subsequent 115 patients ( group 2) enrolled. Hematologic growth factor support was not routinely used. Twenty patients with hepatic dysfunction were enrolled to assess the tolerability of the regimen in this population. All therapies were delivered in an outpatient setting. Results. The overall response rate was 48%, with 12-month estimated survival rates of 53% and 65% for treatment groups 1 and 2, respectively. Response rates were not statistically different between the two treatment schedules. Therapy was well tolerated when delivered on the every 3 of 4-week schedule, including patients with hepatic involvement and those agegreater than or equal to65. Conclusion. Weekly therapy with paclitaxel and 5-fluorouracil with leucovorin is active as first-line therapy for metastatic breast cancer. Use of this regimen should be given consideration, particularly in patients who are not candidates for anthracycline-based therapy.