Mgus And Myeloma What S The Connection

Monoclonal gammopathy of undetermined significance (MGUS) is a benign condition, but it can develop into multiple myeloma, a form of bone marrow cancer. Typically, your family doctor is able to detect the presence of the M protein during a routine physical exam with a blood test.

What is Monoclonal Gammopathy of Undetermined Significance?

MGUS and myeloma have a number of similarities. Like multiple myeloma, MGUS begins in the bone marrow when abnormal plasma cells produce abnormal antibodies. A normal plasma cell makes a specific antibody to combat a specific antigen, and all the plasma cells in your body are able to produce enough varieties of antibodies to fight off most foreign antigens. Abnormal plasma cells produce only one kind of antibody, called monoclonal proteins, or M proteins.

Unlike multiple myeloma, MGUS is a benign condition because the production of M proteins doesn’t overwhelm the production of other antibodies. As a result, the condition rarely produces symptoms and doesn’t require treatment.

Who gets MGUS?

According to the International Myeloma Foundation (2010), approximately two percent of adults over the age of 50 have MGUS. By 70 years of age, three to four percent of adults develop the condition. Clearly, age is a risk factor for MGUS (and myeloma). Gender and race are also risk factors, as men are at greater risk than women for MGUS and African-Americans are at greater risk than any other racial group. Because family history doesn’t appear to be a significant risk factor, your family members aren’t required to undergo MGUS screening.

MGUS and Myeloma

According to the Mayo Clinic (2008), approximately 20 percent of people with MGUS go on to develop multiple myeloma or another serious condition such as B-cell lymphoma or macroglobulinemia. Most people do so only after they’ve had MGUS for a decade or more. Although doctors can’t tell who will go on to develop multiple myeloma and who won’t, several factors can help to determine your level of risk, such as the type of M protein and the amount of it in your blood.

People with MGUS must take annual follow-up tests (usually a blood test) to ensure that their condition is still benign. Close monitoring allows your doctor to detect any serious conditions early on, when treatment is likely to be more effective.

A diagnosis of MGUS doesn’t mean that you have cancer. On the contrary, the vast majority of people with MGUS don’t develop anything more serious and live with MGUS relatively problem-free. In some cases, MGUS simply goes away.


Berenson, J. R. (n.d.). Monoclonal gammopathies of undetermined significance. Retrieved September 27, 2010, from

Gertz, M. (2010). What is monoclonal gammopathy of undetermined significance (MGUS)? Retrieved September 27, 2010, from Tab=0&gParentType=menuitem&gParentId=205&parentIndexPageId=9&parentCategoryId=25

Mayo Foundation for Medical Education and Research. (2008). Monoclonal gammopathy of undetermined significance. Retrieved September 27, 2010, from

National Cancer Institute. (2008). Risk factors. Retrieved September 27, 2010, from