HER-2-Amplified Breast Cancer

Abstract

Amplification of the human epidermal growth factor receptor–2 (HER-2) gene is found in approximately 15 to 30% of breast cancers. Historically, HER-2 overexpression has been associated with aggressive disease and a poor prognosis. However, the use of targeted anti-HER2 therapy has revolutionized the treatment of HER-2-positive disease, and the use of the monoclonal antibody trastuzumab in combination with chemotherapy is now standard of care for tumors greater than 1 cm in size and in node-positive disease. More recently, the value of dual-agent anti-HER-2 therapy has been demonstrated in large clinical trials. This review provides an overview of HER-2-positive breast cancer, its molecular basis, methods of identification, and treatment options and strategies. This review contains 2 figures and 70 references Key words: anti-HER-2 therapy, breast cancer, HER-2-positive breast cancer, HER-2 resistance, lapatinib, neoadjuvant chemotherapy, pertuzumab, small HER-2-positive breast cancer, trastuzumab