The CDX2 protein has been shown to be expressed inintestinal metaplasia of the stomach and intestinal-typegastric cancer, as well as primary and metastaticcolorectal carcinomas. It is not expressed in the normalmucosa of the stomach. Loss of differentiation incolorectal tumours has been linked to decreasedexpression of the CDX2 protein. When determining thegastrointestinal origin of metastatic adenocarcinomasand carcinoids, the CDX2 antibody has been helpful.According to studies, the CDX2 antibody is a bettermarker than CK20. Both ovarian mucinous carcinomasand upper gastrointestinal tract cancers have a highpercentage of positive staining with this antibody.