Prior exposure to chemotherapy: a marker of sensitivity and selection for antiangiogenic therapy in breast cancer?

The identification of patients who are more likely to derive benefit from antiangiogenic therapy is a key to refine patient selection and so maximize clinical benefit, and reduce unnecessary treatment costs. Improved patient selection will equally be effective in minimizing the exposure of non-eligible patients to ineffectual treatment which could be associated with adverse effects as well as delaying effective treatment. Herein, we review the literature from clinical trials suggesting that the addition of antiangiogenic agents to chemotherapy for the treatment of HER-2 negative metastatic breast cancer in patients previously exposed to chemotherapy may deliver differential therapeutic benefit and may serve as a selection criteria in the current absence of a robust biomarker.