This article is part of a series on Recent advances in systemic therapy, edited by Paul Ellis.

Review

Recent advances in systemic therapy: Advances in systemic therapy for HER2-positive metastatic breast cancer

Phuong Khanh H Morrow¹ , Francisco Zambrana^1,2 and Francisco J Esteva¹

¹  Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Holcombe Boulevard, Houston, TX 77030, USA

²  Current address: Department of Medical Oncology, Hospital Infanta Sofia, Paseo de Europa, 34, Madrid 28702, Spain

author email corresponding author email

Breast Cancer Research 2009, 11:207doi:10.1186/bcr2324

Published:	15 July 2009

Abstract

Human epidermal growth factor receptor (HER)2 over-expression is associated with a shortened disease-free interval and poor survival. Although the addition of trastuzumab to chemotherapy in the first-line setting has improved response rates, progression-free survival, and overall survival, response rates declined when trastuzumab was used beyond the first-line setting because of multiple mechanisms of resistance. Studies have demonstrated the clinical utility of continuing trastuzumab beyond progression, and further trials to explore this concept are ongoing. New tyrosine kinase inhibitors, monoclonal antibodies, PTEN (phosphatase and tensin homolog) pathway regulators, HER2 antibody-drug conjugates, and inhibitors of heat shock protein-90 are being evaluated to determine whether they may have a role to play in treating trastuzumab-resistant metastatic breast cancer.