Use

The CDX2 protein, an intestine‑specific transcription factor expressed in the nuclei of epithelial cells throughout the intestine (from duodenum to rectum), is present in primary and metastatic colorectal carcinomas and in intestinal metaplasia of the stomach and intestinal‑type gastric cancer; it is absent in normal gastric mucosa. CDX2 may be used to identify metastatic carcinoma of colonic or other gastrointestinal tract origin when the primary tumor is unknown.