ema refers to epithelial membrane antigen, and ema negativity indicates the possible presence of metastatic cancer. ema is a glycoprotein antibody that is widely found in various epithelial cell membranes as well as tumors of their origin. This antibody can be used to label epithelial as well as epithelial-derived tumors, and can also be used to differentiate between breast cancer and non-epithelial tumors, especially malignant lymphomas and pleomorphic or spindle cell breast cancers suspected of being sarcomas. Not only that, ema test can also be used to determine the problem of lymph nodes without ema and bone marrow with microscopic metastases of breast cancer. If the ema is positive, then it indicates the possibility of malignant lymphoma, melanoma or soft tissue disease. And ema negative indicates the possibility of metastatic cancer, which can be determined on a case-by-case basis to determine whether it is a primary or secondary cancer of the breast. Once the disease is diagnosed, the patient should actively cooperate with the doctor’s treatment and keep a good attitude to avoid deterioration of the disease.