Significant increases were observed in serum VEGF levels for patients with esophageal (573.0±150.6 pg/ml, P<0.01), gastric (360.8±56.9 pg/ml, P<0.01), colorectal (601.8±128.3 pg/ml, P<0.05), whole digestive (369.2±44.9 pg/ml, P<0.05) and gastric and colorectal cancer (499.4±79.6 pg/ml, P<0.005) compared with healthy volunteers (217.8±46.3 pg/ml; Fig. 2). This evidence concerns the gene VEGFA and colorectal cancer.