Cytokeratin (CAM 5.2)

Anti-CAM 5.2 is a mouse monoclonal antibody that was generated by using the human colorectal carcinoma cell line HT24. Anti-CAM 5.2 is not technically a pan-keratin antibody because its reactivity has been reported to be restricted primarily to a few keratins. However, since the few keratins are widely expressed in formalin-fixed, paraffin-embedded tissues, especially in simple and glandular epithelia, this antibody can be successfully used as a reliable marker for neoplasms of epithelial differentiation. Anti-CAM 5.2 reacts with the majority of epithelial tumors, including lung, liver, pancreas, GI tract, breast, genitourinary system, female reproductive organs and some endocrine organs.1 Hepatocellular carcinoma is targeted by anti-CAM 5.2, but not by pan-cytokeratin AE1/AE3 antibody.1 Adrenal cortical carcinomas frequently do not react with anti-CAM 5.2.2 Sebaceous carcinoma, squamous cell carcinoma, and basal cell carcinoma may show an overlapping morphology. Anti-CAM 5.2 is useful to discriminate among them. Literature indicates no reactivity by anti-CAM 5.2 for squamous cell carcinoma while sebaceous carcinoma and basal cell carcinoma show 73% and 44% immunoreactivity respectively.3 Similar to other broad-spectrum keratin antibodies, such as the AE1/AE3 antibody cocktail, anti-CAM 5.2 may stain astrocytic tumors, but the positivity reported for this tumor cross-reactivity is lower than with anti-AE1/AE3.4