Biomarkers and response to bevacizumab--letter.

We read with interest the proteomic study by Collinson and colleagues (1), proposing a biomarker signature with promising ability in predicting benefit from the addition of bevacizumab to standard chemotherapy in epithelial ovarian cancer (EOC). The identification of predictors of benefit from bevacizumab is one of the most pressing priority in medical oncology, as indications for its use have gradually increased and the number of candidate patients has relevantly grown.We also appreciate that authors point out the importance of exploiting phase III randomized trials to throw light on this until today elusive challenge and claim the validation phase as a crucial step in the development of biomarkers.