Cyclophosphamide and Paclitaxel With or Without Trastuzumab in Stage I-II Breast Cancer Who Have Undergone Surgery

PRIMARY OBJECTIVES: I. To determine the toxicities and ability to complete the planned treatment of a dose-dense regimen of cyclophosphamide and paclitaxel with or without trastuzumab in patients with newly diagnosed stage I-II breast cancer. II. To estimate recurrence free survival of a dose-dense regimen of cyclophosphamide and paclitaxel with or without trastuzumab in patients with newly diagnosed stage I-II breast cancer. OUTLINE: SYSTEMIC CHEMOTHERAPY: Patients receive cyclophosphamide intravenously (IV) over 1 hour and paclitaxel IV over 3 hours on day 1. Treatment repeats every 14 days for 6 courses in the absence of disease progression or unacceptable toxicity. MAINTENANCE THERAPY (human epidermal growth factor receptor 2 \[Her-2\] neu positive patients): Patients receive trastuzumab IV over 30 minutes on day 1. Treatment repeats every 14 days for 5 courses and then every 21 days for 14 courses in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up periodically for 3 years.