Use of trastuzumab associated with cisplatin and vinorelbine followed by docetaxel as a neoadjuvant regimen for patients with HER2-positive breast cancer.

637 Background: Some clinical trials have shown the efficacy of neoadjuvant trastuzumab in HER2- positive breast cancer patients. Cardiotoxicity is a relatively frequent side effect, particularly when the drug is associated with anthracyclines or after radiotherapy on chest wall. A reduced heart function is a major issue in young patients and may restrict the use of trastuzumab as adjuvant treatment. Methods: Since 2007 to 2009 we enrolled HER2-positive breast cancer patients into a phase II study of primary systemic therapy. The trial was designed for testing anticancer agents with proven efficacy, synergy with trastuzumab, and mild cardiotoxicity. Weekly trastuzumab was administered in combination with 6 courses of sequential chemotherapy, including 3 cycles of cisplatin 80 mg/m2 on d1 plus vinorelbine 25 mg/m2 on d1+8 q3w, followed by 3 cycles of docetaxel 100 mg/m2 q3w. Peg-filgrastim was given to prevent neutropenia and to potentiate the proposed mechanisms of action of trastuzumab, such as activatio...