CDX2 codes for a homeobox protein involved in intestinal cell differentiation and tumor suppression in the colon. Loss of expression of this protein is correlated with colorectal tumorigenesis and poor survival. The protein is expressed in the nuclei of colonic epithelial cells and in colorectal cancers. Positive staining can also be found in a variety of other tumors such as teratomas, small intestinal carcinomas, bile duct cancers, Barrett’s intestinal metaplasia, and some cases of uothelial cancer. Staining is expected to be nuclear. References: Platet, 2017; Dalerba, 2016; Human Pathol 2011, 42:1653; Am J Clin Path 2008, 130:265