KDR and neoplasm: Development of tumor neovascularization involves secretion of various vascular- growth factors by rapidly growing tumor cells under hypoxic conditions, thus stimulating tumor angiogenesis.8 One of the important growth factors is Vascular Endothelial Growth Factor (VEGF) that binds to the VEGF receptor (VEGFR), stimulating downstream signal transduction and ultimately leading to tumor angiogenesis.9 The theoretical basis for the combined application of VEGF and EGFR-TKI suggests that there is a common downstream signaling pathway between VEGF and HER-1/EGFR.