Advances in anti-HER2 therapy in metastatic breast cancer

Though most patients with breast cancer are cured, there are still many patients progressed to metastatic breast cancer (MBC) and some are diagnosed as MBC. Human epidermal growth factor receptor 2 (HER2) is positive in about 20% all breast cancer patients and considered as a poor prognostic factor. The advent of ant-HER2 therapy has prominently prolonged the time of disease progression and survival for HER2-positive MBC patients. This review summarizes the advance in anti-HER2 therapy in HER2-positive MBC according to the phase III clinical trials, and briefly discusses some new agents and anti-HER2 therapy for HER2 low-or non-expression breast cancer patients.