AdenoCA of Colon : Immunostains - CDX2

Comments:
CDX2 is a transcription factor that plays a vital role in the proliferation and differentiation of intestinal epithelial cells. It is expressed by the vast majority of colorectal carcinomas but may also be seen in lung, ovarian, bladder, and pancreatobiliary carcinomas. In this image, the normal colonic mucosa on the top shows stronger staining with CDX2 as compared to the moderately-differentiated adenocarcinoma below.

Additional Immunostains in Colorectal Cancer: beta-catenin positivity (nuclear staining) is seen in vast majority of colorectal carcinomas. The cause of beta-catenin dysregulation which results in its nuclear localization is APC mutations (70% of cases) or mutations in CTNNB1 (beta-catenin) gene. Carcinoembyronic antigen (CEA) is consistently positive. Other immunohistochemical markers that may be expressed include TAG-72, villin, cathepsin B, hCG, and racemase.