Carcinoembryonic antigen (CEA) is a glycoprotein that is normally expressed in certain parts
of the body and commonly overexpressed in most carcinomas of the colon, rectum, breast,
lung, pancreas, and gastrointestinal tract. Increased expression of CEA promotes increased
intercellular adhesions, which may lead to metastasis. Carcinoembryonic antigen is often
used as a serologic marker of malignancy because of its overexpression in cancer as well
as its measurability in serum. However, because CEA is normally expressed in the body, the …