Anti-Human Epithelial Antigen (Ber-EP4) Helps Define Basal Cell Carcinoma Masked by Inflammation

BACKGROUND: Anti-human epithelial antigen (Dako-Ber-EP4) is an antibody raised in mice that reacts with two glycoproteins of 34 and 49 kD. These glycoproteins are present on the cell surface and in the cytoplasm of basal cell carcinoma (BCC) cells, sweat glands, and some hair follicles in the skin. METHODS: We selected 27 BCCs (15 nodular, 11 morpheic/infiltrative, and one adenoid) and one trichoblastoma and performed rapid immunohistochemical studies with Ber-EP4 and a labeled streptavidin biotin alkaline phosphatase system. RESULTS: Twenty-seven of 27 BCCs and one of one trichoblastoma were positive for Ber-EP4. Thirteen of 27 BCCs stained with Ber-EP4 showed areas of BCC in dense inflammation that were better defined by the Ber-EP4 immunostain than by the H&E stain. In two cases persistent infiltrative BCC was found in the final Mohs margins while appearing negative with routine H&E. Several instances occurred where negative Ber-EP4 in inflammatory fields resulted in tissue sparing with the avoidance of a further Mohs (insurance) layer. CONCLUSION: In conclusion, we found mouse anti-human Ber-EP4 a useful and reliable marker for BCC. This antibody helps to locate latent BCC tumor in inflammatory Mohs margins.