CEA

Carcinoembryonic antigen (CEA) describes a set of highly related glycoproteins involved in cell adhesion. An anti-CEA antibody is an antibody against CEA these antibodies are commonly used in immunohistochemistry to identify cells expressing the glycoprotein in tissue samples. In adults, CEA is primarily expressed in cells of tumours (some malignant/benign) but they are particularly associated with adenocarcinomas, such as those in the colon, lung, breast, stomach, or pancreas. Therefore it can be used to distinguish between these and other similar cancers. For example, it can help to distinguish between adenocarcinoma of the lung and mesothelioma, a different type of lung cancer which is not normally CEA positive (1).

Recommended Controls

Criteria for acceptable staining is a cytoplasmic staining pattern. Recommended control tissue for CEA is a composite block of appendix, liver and a CEA positive colon tumour. Appendix (columnar epithelial cells) and colon tumour cells will demonstrate a strong distinct cytoplasmic staining reaction while the liver will be negative.

Expected staining pattern

Colon tumour

Lung tumour

Liver

Disclaimer

These methods are intended as a guide only. Laboratories that wish to implement these methods should perform internal validation/verification prior to use. The RCPAQAP does not make any claim or warranty for the accuracy or performance of these methods.