Waldenstrom macroglobulinemia is sometimes known as Waldenstrom’s or WM. It’s a rare type of non-Hodgkin’s lymphoma.

Lymphomas are cancers that start in cells called lymphocytes, a type of white blood cell. Lymphocytes play an important role in the immune system.

WM is a cancer of the B lymphocytes or B cells, a type of immune cell. Healthy B cells become plasma cells. Plasma cells create antibodies to fight off harmful bacteria or viruses.

WM damages the B cells so they no longer function normally. The excess production of cancerous B cells prevents healthy B cells from being made. It can also block the bone marrow from making other healthy blood cells.

You probably have questions if you or a loved one is diagnosed with WM. Here are some FAQs and answers about this condition to help you learn more.

WM is a slow-growing type of cancer. People can live for years without symptoms and not even know they have it. For example, the average WM diagnosis age is 70 years old. It’s impossible to predict how long someone will live after a diagnosis of WM. Many factors influence a person’s life expectancy.

However, a WM scoring system groups low, medium, or high risk based on a person’s age and blood work results. This scoring system estimates that around 87% of those in the low risk group will live for 5 years or more, while in the medium and high risk groups, this percentage drops to 68% and 36%, respectively.

New therapies mean that people are living longer with WM. The median survival rate for patients after diagnosis is 14 to 16 years.

Keep in mind that this is based on when the diagnosis is made. Some people may have lived with WM for many years without knowing it.

WM is a type of non-Hodgkin’s lymphoma. Lymphomas are a group of cancers involving lymphocytes, a type of white blood cell.

WM targets the B lymphocytes, also known as B cells. These cells have an important job as part of the immune system response. B cells become plasma cells, which make antibodies to fight off infections.

In WM, cancerous B cells create large antibodies called IgM. Excessive IgM in the blood can make it thicker.

WM is considered a slow-growing type of cancer. It’s possible to have it for several years and not know it. Many people have no symptoms. There is no cure for WM, but treatments can help manage symptoms or complications of WM.

Symptoms of WM can be related to changes in the body’s white and red blood cells. They can also be related to thicker blood from high IgM concentrations.

Signs and symptoms of WM can include:

  • weakness
  • loss of appetite
  • unexplained weight loss
  • fever
  • fatigue
  • low hemoglobin levels
  • headaches
  • feeling short of breath
  • swollen abdomen (from an enlarged liver or spleen, where IgM can build up)
  • numbness and tingling in the hands and feet, from nerve damage

If there are no symptoms, treatment may not be necessary. Your doctor will monitor blood levels and symptoms to watch for any changes. Some people will never need treatment.

Different medications are available to treat WM. If you need treatment, your doctor will discuss the best options with you. Treatments help slow the growth of cancerous B cells and manage symptoms of WM.

If a buildup of IgM is making your blood too thick, you may need to undergo a procedure called plasmapheresis. During this procedure, a medical professional will insert a needle or catheter into your arm, and a pump will slowly remove your blood. Your blood will go through a filtering machine to remove excess IgM. As the blood is thinned out to a normal level, it gets returned to your body.

Family history may slightly increase the risk of developing WM. In about 20% of cases of WM, there is a family history of WM or another blood cancer that affects B cells.

In most cases, WM, just like other cancers, is caused by a random mistake in a cell’s DNA. These genetic errors mean the cell no longer works properly. Damaged cells create more damaged cells, resulting in cancer. We usually don’t know exactly what triggers the DNA error in the first place.

WM is a rare form of blood cancer. There are about 1,000–1,500 cases diagnosed in the United States every year. The low rates of WM make it harder to see patterns and find out what might increase the risk.

WM is more likely diagnosed in people in their 60s–70s. It’s also more common in men.

A condition called monoclonal gammopathy of undetermined significance (MGUS) is linked to WM. MGUS causes a higher than normal IgM antibody in the blood, but not at the level seen in WM.

MGUS is not cancer, but it slightly increases the odds of developing WM or other blood cancers. Every year, about 1%–2% of people with MGUS will develop cancer.

People with MGUS are monitored for any change in symptoms or blood levels.

Waldenstrom macroglobulinemia (WM) is a rare type of lymphoma. This cancer affects the B cells or B lymphocytes. These are a type of white blood cell involved in the immune response. Many people live with WM for years with no symptoms. It is a slow-growing type of cancer that often doesn’t need any treatment.

Advances in treatment mean that people are living longer with WM. The median survival after diagnosis is now 14 to 16 years. A healthcare team monitors people with WM to watch for changes in symptoms or blood levels. If treatment is needed, there are several options to help manage WM.