Epithelial Membrane Antigen (EMA)

Epithelial Membrane Antigen (EMA), also known as milk fat globule membrane protein, is present on the luminal surface of mammary gland epithelium. Although EMA is primarily located in mammary gland epithelium, other normal epithelia (e.g., lung) will also react against EMA antibody. Cells obtained from solid metastases and pleural effusions accompanying a breast cancer will react with EMA antibody. It may also be useful for identification of meningioma. Human colon carcinoma, osteosarcoma, kidney carcinoma, hepatocellular carcinomas, adrenal carcinoma, embryonal carcinoma, liposarcoma, lung carcinoma, and mixed parotid tumor do not stain with EMA antibody. The combination of positive staining for keratin with negative EMA can be used to phenotype the above-mentioned epithelial tumors. This antibody stains positive on membrane of mammary gland and other epithelial cells.