Targeted therapy in HER2-positive breast cancer.

Treatment options for breast cancer vary based on tumor surface markers and clinical factors, including cytotoxic chemotherapy, hormonal therapy, biological therapy or a combination thereof. An important molecular determinant of therapy is the human epidermal growth factor receptor 2 (HER2) positivity of the tumor, which has been identified in 20-25% of breast cancers and is a prognostic marker of poor outcome. The advent of HER2-targeted therapies has significantly improved the survival of patients with HER2-positive breast cancer. This review focuses on current HER2-targeted therapeutic options for patients with HER2-positive breast cancer, including monoclonal antibodies and tyrosine kinase inhibitors (TKIs).