Ep-CAM/Epithelial Specific Antigen (Ber-EP4)

Epithelial cell adhesion molecule (Ep-CAM) is an approximate 40 kDa transmembrane glycoprotein. In paraffin sections, the protein is detected with many antibodies like anti-Ber-EP4 and anti-MOC-31. Ep-CAM (Ber-EP4) is normally expressed at the basolateral membrane of cells in the majority of epithelial tissues.1 It is not expressed in adult squamous epithelia, hepatocytes, myoepithelial cells, mesothelial cells or fibroblasts. Ep-CAM is found in the large majority of adenocarcinomas of most sites (50-100%) in various studies; as well as neuroendocrine tumors, including small cell carcinoma.2 Renal clear cell carcinoma, renal oncocytoma and hepatocellular carcinoma stain in a minority of the cases,3 but papillary renal cell carcinoma, chromophobe renal cell carcinoma and cholangiocarcinoma stain with anti-Ber-EP4 at a higher percentage. Basal cell carcinoma is anti-Ber-EP4 positive in almost all cases.4 Ep-CAM can be of great help in the differentiating malignant involvement in the peritoneal and pleural cavities.5,6,7