What Are the Risk Factors for Waldenstrom Macroglobulinemia?

A risk factor is anything that affects your chance of getting a disease such as cancer. Different cancers have different risk factors. Some cancer risk factors, like smoking, can be changed. Others, like a person’s age or family history, can’t be changed.

Researchers have found a few risk factors that make a person more likely to develop Waldenstrom macroglobulinemia (WM). But most people with these risk factors never develop WM.

Monoclonal gammopathy of undetermined significance

Monoclonal gammopathy of undetermined significance (MGUS) is an abnormality of antibody-making cells that is related to multiple myeloma and WM. In MGUS, like WM and multiple myeloma, abnormal cells in the bone marrow make large amounts of one particular antibody. This antibody is called a monoclonal (or M) protein, and the condition is called a monoclonal gammopathy.

As long as the patient has no symptoms from the abnormal cells or the M protein they make, the abnormal cells make up less than 10% of the bone marrow, and the amount of abnormal M protein in the blood is not very high (less than 3 g/dl), this condition is called MGUS.

MGUS itself does not cause health problems, but each year about 1% to 2% of people with MGUS go on to develop a related cancer (like multiple myeloma, WM, or lymphoma) or another serious health problem (like amyloidosis).


The risk of WM goes up with age. It is rare among people younger than 50 years old.


WM is more common among whites than among African Americans. In contrast, multiple myeloma is about twice as common among African Americans as white Americans. The reasons for these differences are not known.


Men are more likely than women to develop this disease. The reason for this is not known.


Inherited genes seem to play a role in at least some people who get WM. About 1 in 5 people with WM has a close relative with WM or with a related B-cell disease, such as MGUS or certain types of lymphoma or leukemia.

Hepatitis C

Hepatitis C is caused by infection with a virus (known as the hepatitis C virus, or HCV). Some studies have found that people with chronic hepatitis C infection might be more likely to develop WM than people without the virus. But not all studies have found such a link.

Certain autoimmune diseases

Some research has suggested that people with certain types of autoimmune disease, such as Sjögren (Sjogren) syndrome, might be at higher risk for WM.

The American Cancer Society medical and editorial content team
Our team is made up of doctors and master's-prepared nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: October 20, 2014 Last Revised: January 28, 2015

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