Waldenström macroglobulinemia (WM), also known as lymphoplasmacytic lymphoma, is one type of cancer of the lymph system. Like other lymphomas, WM occurs because something goes wrong inside your lymphocytes, a type of white blood cell made in your bone marrow and found in your blood and lymph tissue.
Seattle Cancer Care Alliance (SCCA) offers comprehensive treatment for WM from a team of experts.
- What is Waldenström macroglobulinemia?
- What causes WM?
- How common is WM?
- Next steps
What is Waldenström macroglobulinemia?
WM is a type of non-Hodgkin lymphoma — but a unique type that requires different treatment.
- WM begins in B lymphocytes (B cells), which make antibodies. Antibodies attach to bacteria and to cells infected with a virus or bacteria so that other immune cells recognize them and know to destroy them.
- WM cells grow mainly in your bone marrow, where they can crowd out normal, healthy blood cells that your body needs (white blood cells, red blood cells and platelets).
- WM cells also make large amounts of an antibody called immunoglobulin M (IgM), sometimes referred to as an M protein (monoclonal protein). IgM is a large antibody (macroglobulin) that can build up around your body.
Symptoms of Waldenström macroglobulinemia
WM symptoms may be similar to symptoms caused by other conditions that are not related to cancer. Check with your doctor if you feel concerned about any symptoms you have.
Symptoms of WM may include:
- Loss of appetite or unexplained weight loss
- Swollen or enlarged lymph nodes or spleen
- Peripheral neuropathy, such as numbness or tingling in your hands or feet
- Unexplained fever
- Heavy sweating (especially at night)
- Severe or widespread itchy skin
If IgM builds up in your blood, it may thicken your blood (a condition called hyperviscosity) and slow down the flow. This can lead to symptoms such as:
- Vision problems
- Loss of coordination
- Nosebleeds or bleeding gums
In some people, the large proteins clump in cooler parts of the body — like the tip of the nose, the ears and the fingers and toes — blocking blood vessels and causing pain. You might hear these proteins referred to as cryoglobulins, which means “cold antibodies.”
Amyloidosis can occur if part of the IgM antibody (called the light chain) builds up in organs like your heart and kidneys.
Some people have no symptoms at the time of diagnosis. Instead, their disease is found when they have blood tests for another reason. This is called asymptomatic or smoldering WM.
Diagnosing Waldenström macroglobulinemia
If your doctor suspects you may have WM, they will do a physical exam to look for signs of the disease and ask about your symptoms, medical history, family history and risk factors.
You might also have any or all of these tests:
- Blood tests — to look for anemia and other complications of WM, to check your IgM levels (always elevated in WM) and to check the thickness of your blood (serum viscosity).
- Urine tests — to look for abnormal proteins.
- Bone marrow tests — taking samples of bone marrow and a small piece of bone from your pelvis using a needle (bone marrow aspiration and biopsy) to check for cancer cells.
- Lymph node biopsy — taking samples from a lymph node to check for cancer cells.
- Molecular tests — to help diagnose and identify specific features of your disease as well as inform your care. Genetic changes, like mutations in the MYD88 or CXCR4 gene, help predict whether you will develop WM symptoms and need treatment.
- Imaging tests — such as a chest X-ray, ultrasound, computed tomography (CT) scan or positron emission tomography (PET) scan to see pictures of the inside of your body and look for enlarged lymph nodes, tumors or other cancer activity.
What causes Waldenström macroglobulinemia?
The exact cause of WM is unknown. You may be at higher risk if any of these is true:
- You have a blood disorder called monoclonal gammopathy of undetermined significance (MGUS). About 1 to 2 percent of people with MGUS will develop a related cancer, like WM, lymphoma or multiple myeloma or another serious condition, like amyloidosis.
- You have a family history of the condition. About 1 in 5 people with WM has a close relative with WM or a related B-cell disease.
- You have hepatitis C. Some, but not all, studies show infection with the hepatitis C virus raises WM risk.
- You have certain autoimmune diseases, such as Sjögren syndrome, which might increase risk.
Keep in mind that many people who get the disease have none of these risk factors, and most people with these risk factors do not develop the disease.
How common is Waldenström macroglobulinemia?
About 1,000 to 1,500 adults in the U.S. are diagnosed with WM each year.