These adenomas are characterized by allelic losses in the adenomatous polyposis coli (APC) gene which alters the Wnt–β-catenin pathway, activation of prostaglandin signaling induced by inflammation or mitogen-associated upregulation of cyclooxygenase-2 (COX-2), TP53 mutation and loss of heterozygosity at 18q chromosome [17, 21]. This evidence concerns the gene PTGS2 and adenoma.