Biomarkers in tissue from patients with upper gastrointestinal cancers treated with erlotinib and bevacizumab.

Malignancies in the upper gastrointestinal (UGI) tract are amongst the most aggressive cancers and only few treatment options exist. We have recently analysed data from a phase II trial where patients with UGI cancers were treated with erlotinib and bevacizumab. The combination therapy could not be recommended in an unselected population of patients with chemo-refractory UGI cancer. However, a subpopulation of patients did benefit from the therapy. In this prospectively planned biomarker study we investigated vascular endothelial growth factor A (VEGF-A), VEGF receptor 2 (VEGFR-2) and epidermal growth factor receptor (EGFR) by immunohistochemistry and KRAS mutation status detected by PCR as potential predictors of effect of therapy. High VEGF-A expression was correlated to longer overall survival (HR: 0.8, 95%CI: 0.7-0.9) and high VEGFR-2 expression to shorter progression free survival (HR: 1.4, 95%CI: 1.0-1.9). EGFR expression and KRAS mutation status were not correlated to response or survival. We conclude that VEGF-A and VEGFR-2 could potentially be predictive markers in patients with UGI cancers treated with erlotinib and bevacizumab.