Myeloma is a cancer of plasma cells found in the bone marrow. Multiple myeloma is one of several types of blood and marrow cancer that UCHealth specialists can treat with proven procedures and advanced technology.
Multiple myeloma: learn more
Your bone marrow produces many types of cells, including plasma cells, that in turn produce antibodies to help your immune system fight infections.
Myeloma occurs when healthy plasma cells become abnormal plasma cells and grow out of control. This suppresses the growth of normal plasma cells, red blood cells, white blood cells and platelets in the marrow. Myeloma also causes structural bone damage, which can lead to fractures or breaks over time.
Myeloma is usually called multiple myeloma because 90% of patients have multiple bone lesions when diagnosed or over the course of the illness. We do not fully understand what causes myeloma, and there are no known ways to prevent it.
Other plasma cell disorders
There are other plasma cell disorders that also have abnormal plasma cells but do not meet the criteria to be called active multiple myeloma. These include:
Extramedullary plasmacytoma is myeloma that started outside the bone marrow in the lymph glands, sinuses, throat, liver, digestive tract or under the skin.
Light chain amyloidosis, AL or primary amyloidosis. A disorder of abnormal plasma cell growth, but with lower amounts of abnormal plasma cells in the bone marrow compared to multiple myeloma. Antibodies are made up of joined protein chains, two short light chains and two longer heavy chains. In light chain amyloidosis, abnormal plasma cells make too many light chains which are shorter and weigh less than the heavy chains. The light chains build up in tissues as an abnormal protein known as amyloid, which can enlarge certain organs and adversely affect their performance.
Monoclonal gammopathy of undetermined significance (MGUS). Like regular plasma cells, myeloma cells can produce antibodies, but they are not healthy, functioning antibodies. Instead, they make monoclonal protein (M protein), which is a non-functional antibody. By definition, this is the only abnormality seen; MGUS has no other impact on organ function, but does have a risk of progressing to multiple myeloma of approximately 1% / year. Usually, patients with MGUS only require periodic monitoring in the clinic without treatment.
Smoldering multiple myeloma (SMM). An early or asymptomatic myeloma that isn’t causing problems with internal organs or bones. Many people with SMM do not need treatment right away, but because it can become active in months to years, we watch them closely for signs of myeloma.
Solitary plasmacytoma is a mass of myeloma cells that involves only one site in the bone, or other organs such as in the upper respiratory tract, including the nose and throat or gastrointestinal systems. Solitary plasmacytomas are usually treated with radiation alone, but monitoring is required afterwards due to a risk of recurrence and developing multiple myeloma.
Waldenstrom macroglobulinemia (WM). The cancer cells in people with WM combine features of both multiple myeloma and non-Hodgkin lymphoma (NHL). WM can present as enlargement of the spleen, liver, or lymph nodes. The WM cells characteristically produce an IgM-type M-protein which can be followed for response to therapy.