The expanding role of bevacizumab in the treatment of human epidermal growth factor receptor 2-negative breast cancer.

A growing body of evidence consistently demonstrates the activity of bevacizumab, a monoclonal antibody that targets all isoforms of vascular endothelial growth factor (VEGF)-A, in combination with chemotherapy in the treatment of patients with human epidermal growth factor receptor 2 (HER2)-negative, metastatic breast cancer. Clinical benefit has been limited to prolonged progression-free survival. As yet, combination regimens have failed to demonstrate a survival advantage. Emerging research suggests that single-nucleotide polymorphism in VEGF may predict response to combined therapy.