How Waldenstrom Macroglobulinemia Is Diagnosed and Treated

What is Waldenstrom's macroglobulinemia and what do you need to know if you are diagnosed with this disease?

Definition of Waldenstrom Macroglobulinemia

Waldenstrom macroglobulinemia (WM) is a rare type of non-Hodgkin lymphoma (NHL). WM is a cancer that affects B lymphocytes (or B cells) and is characterized by an overproduction of proteins called IgM antibodies. WM may also be referred to as Waldenstrom’s macroglobulinemia, primary macroglobulinemia, or lymphoplasmacytic lymphoma.

In WM, the cancer cell abnormality occurs in B lymphocytes just before they mature into plasma cells. Plasma cells are responsible for producing infection-fighting antibody proteins. Therefore, an increased number of these cells leads to an increased amount of a specific antibody, IgM.

Signs and Symptoms of WM

WM can affect your body in two ways.

Bone Marrow Crowding

The lymphoma cells can crowd your bone marrow, making it difficult for your body to produce adequate numbers of platelets, red blood cells, and white blood cells. As a result, these deficits will cause signs and symptoms that are typical of anemia (a low red blood cell count), thrombocytopenia (a low platelet count), and neutropenia (a low neutrophil count — neutrophils are one type of white blood cell). Some of these symptoms may include:

• Abnormal or unusual bleeding, such as bleeding gums, strange bruises, or nosebleeds
• Feeling unusually tired, even though you are getting enough sleep
• Shortness of breath with any exertion
• Frequent infections or illness that you just can’t seem to fight off
• Pale skin

Hyperviscosity

In addition to its effect on bone marrow, the increased amount of the IgM protein in your blood can cause what is called hyperviscosity. In short, hyperviscosity means that the blood becomes thick or gooey and may have difficulty flowing easily through your blood vessels. Hyperviscosity causes another distinct set of signs and symptoms that include:

• Changes in vision, such as blurriness or worsening of vision
• Mental status changes, such as confusion
• Dizziness
• Headaches
• Numbness or tingling in the feet or hands

As with other types of lymphoma, cancer cells can be present in other areas of the body, especially in the spleen and liver, and cause pain. Swollen lymph nodes may also be present.

You must remember that these signs and symptoms may be subtle and can be present in many other less serious conditions. If you have concerns about any changes to your health, it is always best to consult your practitioner or healthcare provider.

Causes of WM

As in the case of many other types of cancer, it is not known what causes WM. However, researchers have identified some factors that seem to be more common in people with the disease. Known risk factors include:

• Age older than 60 years
• A history of a condition called monoclonal gammopathy of undetermined significance (MGUS)
• A history of WM in their family
• Having a hepatitis C virus infection

In addition, WM occurs in men more often than women, and in Caucasian people more often than African Americans.

Diagnosing WM

As with other types of blood and marrow cancers, WM is usually diagnosed using blood tests and a bone marrow biopsy and aspirate.

Complete blood counts may show a decrease in the numbers of normal healthy blood cells, such as red blood cells, platelets, and white blood cells. In addition, the blood tests will show an increase in the amount of IgM protein.

Bone marrow biopsy and aspirate will provide details about the types of cells in the marrow, and help the healthcare provider differentiate WM from other forms of lymphoma.

How Is WM Treated?

WM is a very uncommon type of cancer, and researchers still have a long way to go in learning about the different treatment options available, and how they compare to each other in terms of their effectiveness. As a result, people who are newly diagnosed with WM may choose to participate in clinical trials to help scientists in understanding more about this condition.

There is no known cure for WM at this time, but there are a number of options that have shown some success in controlling the disease.

• Plasmapheresis: The abnormally high amounts of IgM in the blood can cause hyperviscosity or thickness of the blood. This thick blood may make it difficult for nutrients and oxygen to be delivered to all of the cells of the body. Removing some of the IgM from the blood can help to decrease the thickness of the blood.​ During plasmapheresis, the patient’s blood is slowly circulated through a machine that removes the IgM and then returned into their body.
• Chemotherapy and Biotherapy: Patients with WM are often treated with chemotherapy. There are several different combinations of drugs that may be used. Some of these include combining Cytoxan (cyclophosphamide) plus Rituxan (rituximab) and dexamethasone, or Velcade (bortezomib) plus Rituxan and dexamethasone. There are many other drugs and combination of drugs being used treating WM both in practice and in clinical trials.
• Stem Cell Transplant: It is unknown what role stem cell transplantation will play in treating WM. Unfortunately, the advanced age of many WM patients may limit the use of allogeneic transplants (in which stem cells come from a donor), which can have toxic side effects, but autologous transplant (using the person's own stem cells) following high-dose chemotherapy may be a reasonable and effective option, especially for those who have a relapse of their disease.
• Splenectomy: Like other types of NHL, patients with WM may have an enlarged spleen or splenomegaly. This is caused by a build-up of lymphocytes in the spleen. For some patients, removal of the spleen, or splenectomy, may provide a remission from WM.
• Watch and Wait: Until WM is causing problems, most clinicians will opt for a “watch and wait” approach to treatment. In this case, you will continue to be closely monitored by your specialist and delay more aggressive therapies (and associated side effects) until you really need them.​ While it may be difficult to imagine going through your daily life with cancer in your body and not doing anything about it, research has shown that patients who delay therapy until they begin having complications from it do not have worse outcomes than those people who start treatment right away.

Summary

Waldenstrom macroglobulinemia, or WM, is a very rare type of NHL that is only diagnosed in about 1,500 people per year in the US. It is a cancer that affects the B lymphocytes and causes an abnormally high amount of the antibody IgM in the blood.

Because it is so uncommon, and because our knowledge of lymphoma is constantly expanding, there is currently no single standard treatment regimen for WM. Therefore, many patients who are newly diagnosed with WM are encouraged to participate in clinical trials to help scientists learn more about this unusual blood cancer, and in the hope that they will have the opportunity to use the medications now which will become the standard in the future.