title: HER2-positive breast cancer: beyond trastuzumab.
abstract: The outlook for patients with HER2-positive breast cancer was revolutionized by the development of trastuzumab (Herceptin), a humanized murine monoclonal antibody. Use of this agent led to improved overall survival when it was added to chemotherapy for the treatment of metastatic breast cancer. Improved understanding of mechanisms of resistance to trastuzumab has facilitated the development of novel agents for HER2-positive breast cancer, and also resulted in superior outcomes when added to chemotherapy in the adjuvant setting. This review explores the use of several such agents, including lapatinib (Tykerb), HSP90 inhibitors, T-DM1, and other tyrosine kinase inhibitors. Emerging data from trials of these agents indicate that the HER2 pathway remains a valid therapeutic target following disease progression on trastuzumab, and suggest a promising role for combined HER2 blockade with two or more agents.
authors.affiliation: Breast Cancer Medicine Service, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA. murphyc@mskcc.org
authors.forename: Conleth G
authors.initials: CG
authors.lastname: Murphy
authors.forename: Monica
authors.initials: M
authors.lastname: Fornier
mesh_terms: D000911:Antibodies, Monoclonal / Q000494:pharmacology; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy*; D017024:Chemotherapy, Adjuvant; D019008:Drug Resistance, Neoplasm; D005260:Female; D006801:Humans; D000077341:Lapatinib; D047428:Protein Kinase Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D011799:Quinazolines / Q000008:administration & dosage / Q000627:therapeutic use; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000037:antagonists & inhibitors*; D000068878:Trastuzumab
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D000077341:Lapatinib; D047428:Protein Kinase Inhibitors; D011799:Quinazolines; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab; C508053:ERBB2 protein, human