M protein is a large amount of abnormal immunoglobulin produced by monoclonal malignant proliferation of plasma cells or B lymphocytes. It is essentially a fragment of immunoglobulin or immunoglobulin, also known as monoclonal protein, monoclonal immunoglobulin, myeloma protein. , or M- spike.
Because it is more common in multiple myeloma, macroglobulinemia and malignant lymphoma, it is a disease beginning with M, so it is called "M protein". M protein positive found in: malignant monoclonal gamma globulinemia, such as multiple myeloma, heavy chain disease, malignant lymphoma, chronic lymphocytic leukemia, macroglobulinemia, etc.; secondary monoclonal gamma globulinemia Such as non-lymphoid reticular system tumor, monocytic leukemia, cryoglobulinemia, etc.; benign M proteinemia, the incidence rate of the elderly over 70 years old is about 3%