CDX2 Test

The CDX2 is a unique protein that is encoded in the CDX2 gene. The gene is found on the 13th chromosome, and has a highly special function of regulating the proliferation and differentiation of intestinal epithelial cells. In mammals, it is one of the most important genes for embryogenesis – since it is responsible for the formation of the placenta. As a protein, CDX-2 is found in the nuclei of epithelial cells throughout the digestive tract – from the duodenum to the rectum. Modern medical research has found out the CDX2 gene is an active marker of Type-II and Type-III intestinal cancer.

The CDX2 protein is expressed in primary and metastatic colorectal tumors or carcinoma, but it has also been found in abnormal changes to the tissue structure of the stomach, as well as in cases of gastric cancer. To extract the tissue from intestinal sections, a biopsy needs to be performed – extracting a tissue block as a specimen, which is formalin-fixed and paraffin-embedded in nature. In addition, the tissue block should be laid out on one (1) unbaked and unstained slide, cut at 4 to 5 microns for Hematoxylin and Eosin staining; as well as 2-3 positively-charged unstained slide for each microbody-type test.

The biopsy is used to assist in the diagnosis of diseases in the intestinal lining. The CDX2 marker is especially relevant for the discovery of the presence of intestinal carcinomas and cancerous tumors. In addition, the marker can also be used to find the presence of unknown tumors within the gastrointestinal tract.

The process for the extraction of intestinal epithelial cells involves a process known as the small bowel biopsy. The process should be conducted at a proper medical facility such as a hospital or a diagnostic center, and requires the assistance of a trained medical professional as well as a medical practitioner trained in endoscopic procedures. The process is as follows: The patient has to swallow a capsule attached to a long, thin polyethylene tube. Once the capsule reaches the small intestine, mild suction is applied to pull the tissue sample into the capsule. The capsule is slowly retracted out of the stomach through the esophagus. While the process sounds alarming, it is one of the least invasive biopsy procedures, and is almost painless. However, the patient should not take food or water for four hours before the procedure is done. In addition, the physician must be informed about certain drugs that have been taken beforehand such as aspirin, ibuprofen or naproxen. These medications must be reduced for some time before the procedure to minimize the risk of bleeding complications.