CEA (Carcinoembryonic Antigen) is a cell-surfaceglycoprotein involved in cell adhesion and tumorprogression. It is strongly expressed in:

• Colorectal adenocarcinoma

• Lung adenocarcinoma

• Breast carcinoma (variable)

• Gastrointestinal malignanciesCEA

expression is rare in mesothelioma and most benignmesothelial tissues, making it a useful research marker todistinguish adenocarcinoma vs. mesothelial tumors.