Combination Chemotherapy in Treating Women With Breast Cancer Who Have Undergone Surgery

OBJECTIVES: * Compare the 5-year and 10-year disease-free survival and overall survival of women with completely resected early stage breast cancer treated with adjuvant paclitaxel, epirubicin, and cyclophosphamide with or without gemcitabine. * Compare the toxicity, dose-intensity, and tolerability of these regimens in these patients. * Compare the serious adverse events in patients treated with these regimens. OUTLINE: This is a randomized, multicenter study. Patients are stratified according to nodal status (negative vs 1-3 vs 4 or more), age (50 and under vs over 50), estrogen receptor status (negative vs weakly positive vs positive), concurrent radiotherapy (no vs yes), HER2 status (3+ overexpression vs other vs not measured), and country. Patients are randomized to 1 of 2 treatment arms. * Arm I: Patients receive epirubicin IV, cyclophosphamide IV, and paclitaxel IV over 3 hours on day 1. Patients also receive gemcitabine IV over 30 minutes on days 1 and 8. Treatment repeats every 3 weeks for 4 courses in the absence of disease progression or unacceptable toxicity. * Arm II: Patients receive epirubicin, cyclophosphamide, and paclitaxel as in arm I. Patients are followed every 3 months for 6 months, every 6 months for 3 years, and then annually for 6 years. PROJECTED ACCRUAL: A total of 3,000 patients (1,500 per treatment arm) will be accrued for this study within 3-4 years.