Waldenstrom's Macroglobulinemia
Description of Waldenstrom's Macroglobulinemia
Waldenström’s macroglobulinemia (WM) is a rare, indolent (slow-growing) non-Hodgkin’s lymphoma (cancer that begins in the cells of the immune system). WM is also called lymphoplasmacytic lymphoma. It starts in plasma cells, which develop from white blood cells called B lymphocytes or B cells.
B cells are an important part of the body’s immune system. They form in the lymph nodes, spleen, and other lymphoid tissues, including bone marrow (the soft, spongy tissue inside bones). Some B cells become plasma cells, which make, store, and release antibodies. Antibodies help the body fight viruses, bacteria, and other foreign substances.
In WM, abnormal plasma cells multiply out of control, producing large amounts of a protein called monoclonal macroglobulin (IgM) antibody. High levels of IgM in the blood cause hyperviscosity (thickness or gumminess), which leads to many of the symptoms of Waldenström’s.