Generally, serum VEGF is measured to monitor the VEGF expression before the initiation of therapy however VEGF concentration determined from circulation are invasive and are obscure due to the fact that circulating VEGF not only measures the tumor VEGF but also the VEGF secreted by platelets, granulocytes, monocytes, mast cells, and lymphocytes which might give a false positive result [29]. This evidence concerns the gene VEGFA and neoplasm.