Waldenström's macroglobulinaemia

Waldenström's macroglobulinaemia is a type of cancer that has features in common with myeloma and some types of lymphoma. The condition is so called because a Swedish doctor called Waldenström described it in 1944.

Waldenström's macroglobulinaemia affects a specific type of white blood cell called the B-lymphocyte.  B-lymphocytes are produced in the bone marrow and form part of the immune system.

Some B-lymphocytes develop into specialised cells, called plasma cells, which produce antibodies when foreign substances such as bacteria or viruses are detected in the body.

These antibodies help to eliminate foreign substances from the body. Five classes of antibody (also called proteins or immunoglobulins [Ig]) have been identified, IgA, IgD, IgE, IgG and IgM.

In Waldenström's macroglobulinemia, B-lymphocytes do not develop into mature plasma cells, but into a type of cancer cell known as a 'lymohoplasmacytoid' cell. These abnormal cells grow more quickly than normal cells would and can invade and build up in the bone marrow, spleen, and lymph glands. These cells also produce and release excessive amounts of the IgM protein into the blood.