The expression of certain cell adhesion molecules (such as integrins and E-cadherin) and growth factors (such as transforming growth factor-beta (TGF-β) and vascular endothelial growth factor (VEGF)), which are involved in tumor invasion and metastasis, may differ between tumors in the lower small bowel and the duodenum, affecting their metastatic potential (25–27). This evidence concerns the gene VEGFA and neoplasm.