The role of bevacizumab in breast cancer

Neoangiogenesis and expression of the main angiogenic factor Vascular endothelial growth factor (VEGF) are critical steps already present at an early stage of breast cancer development. As tumor growth progresses other pro-angiogenic factors, including bFGF, TGFa and IL-8, are overexpressed and act in addition to VEGF. VEGF expression has been associated to poor prognosis and therapy outcome in breast cancer. Moreover, several studies have documented that HER-2 overexpression induces VEGF expression/secretion and neovascularization and that VEGF expression increases when tumors become resistant to treatment. On these bases the anti-VEGF drug Bevacizumab has been evaluated in the clinical setting in breast cancer patients. Recently, phase III studies have demonstrated that Bevacizumab in combination with taxanes produces a high rate of responses and increases the Progression Free survival of breast cancer patients. A large array of studies is currently ongoing with Bevacizumab in combination with chemotherapy and hormone-therapy in the metastatic, neoadjuvant and adjuvant setting.