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What is Multiple Myeloma?

Multiple myeloma is the second most common blood cancer in the U.S. There are more than 77,000 people living with multiple myeloma in the U.S. The disease is more common in men than in women.

Multiple myeloma is a cancer of the plasma cells, a type of white blood cell that develops in the bone marrow. Plasma cells make antibodies and help the immune system fight off infection and disease. In people with multiple myeloma, the plasma cells become abnormal and produce a protein called an M protein. When these abnormal plasma cells multiply, they can create bone lesions tumors that can cause damage to the bones and lead to pain.

Multiple myeloma can be categorized into three groups:

  • Monoclonal gammopathy of undetermined significance (MGUS): A precursor to multiple myeloma. In a person with MGUS, a low level of M protein is present but the condition is usually not accompanied by symptoms and usually causes no problems. People with MGUS may develop multiple myeloma over time. If you have MGUS, you will usually have periodic checkups to monitor your level of M protein. If there is no increase, MGUS does not require treatment.
  • Smoldering or asymptomatic myeloma: A slightly higher level of M protein is present but the person does not have symptoms of multiple myeloma. Most people with smoldering myeloma develop multiple myeloma, and are closely monitored for signs that the cancer is growing.
  • Symptomatic myeloma: A person with symptomatic myeloma experiences common symptoms of multiple myeloma, which can lead to infections, abnormal bleeding and fatigue, and/or bone pain and possibly numb or weak feelings in the legs or arms.

Risk Factors, Signs and Symptoms

Risk Factors

Doctors do not know what causes multiple myeloma, but researchers have identified that specific factors may increase a person’s risk of developing multiple myeloma. These include:

Age - Most people with multiple myeloma are diagnosed after age 65 and the disease is rare in people younger than 35.

Family History - Studies have found that a person's risk of multiple myeloma may be higher if a first degree relative had the disease.

History of Monoclonal Gammopathy of Undetermined Significance (MGUS) - MGUS is a benign condition in which abnormal plasma cells make M proteins. Usually, there are no symptoms, and the abnormal level of M protein is found with a blood test.

Race/Sex - The risk of multiple myeloma is highest among African Americans and lowest among Asian Americans. Men are more commonly diagnosed with this type of cancer than women.

Signs & Symptoms

Multiple myeloma can cause symptoms including bone pain, weakness, fatigue, thirst, increase in infections and fevers, impaired kidney function, weight loss, nausea, constipation and increased or decreased urination.

Common signs and symptoms/complications of multiple myeloma include:

  • Anemia - A person with a low red blood cell count (anemia) will exhibit symptoms such as fatigue, weakness, shortness of breath and dizziness due to inadequate oxygenation to tissues.
  • Bone pain - Myeloma cells make a substance that causes the bone to dissolve, which can cause small areas of bone weakness or “soft spots” and is painful. While any bone can be affected, pain in the backbone, hip bones, and skull is most common. 
  • High level of calcium in blood - When bone damage due to intrusion of myeloma cells occurs, the bone can dissolve and can release calcium into the blood. If this happens, a person will feel very thirsty, urinate frequently, experience a loss of appetite, constipation, and feel drowsy or confused. Hypercalcemia can affect almost every organ system in the body.
  • Fever and infections - People with multiple myeloma may develop frequent fevers and infections since their immune system is compromised and myeloma tumors weaken the body’s defenses against infection.
  • Kidney damage - Myeloma protein or an increase in the amount of calcium in the blood can damage the kidneys, which makes it harder for the body to rid itself of excess salt, fluid, and body waste products. 
  • Nerve pain - Nerve damage and subsequent nerve pain can result from a number of issues: the disease itself, result of spinal cord compression, and from treatments for the disease. Bones in the spine may get weak and even collapse. They can press on certain nerves, causing severe pain, numbness, and/or muscle weakness. Abnormal proteins made by myeloma cells can damage nerves, causing weakness and numbness. People with multiple myeloma can experience prickling or tingling, numbness, sensitivity to touch, and muscle weakness in their extremities due to the disease itself as well as from treatments for myeloma.

Diagnosis and Staging


Doctors sometimes find multiple myeloma through routine blood tests or a bone x-ray after people come in for symptoms such as fatigue, weight loss, extreme thirst, infections, pain or broken bones.

If your symptoms suggest multiple myeloma, you may have one or more of the following tests:

  • Blood tests - To check for the number of white blood cells, red blood cells and platelets in the blood. The blood may also be checked for different proteins, including M protein and other antibodies. Tests may also check for high levels of calcium and creatinine levels to see how well the kidneys are working. 
  • Urine tests - To identify abnormal levels of proteins and antibodies and check kidney function.
  • X-Ray or Skeletal Survey - To show fractures, breaks or hollowed out areas of bone, which may be caused by multiple myeloma.
  • Bone marrow biopsy and aspiration - To confirm a multiple myeloma diagnosis, a doctor must remove samples from a person’s bone marrow (aspiration) and a piece of the bone (biopsy) to check for the presence of abnormal plasma cells. A doctor (pathologist) will look at the bone marrow tissue under a microscope to review the appearance, size and shape of the cells, to determine if myeloma cells are present, and if so, how many. The aspirate (liquid) portion of the sample is routinely sent for other tests which will help determine the exact type and genetics of the disease. 


Doctors use tests to help determine how much the cancer has spread and the appropriate treatment options. Knowing all you can about staging lets you take a more active role in making informed decisions about your treatment plan. There are two different types of staging symptoms that a doctor may use to categorize multiple myeloma.

The traditional system that has been used to stage multiple myeloma is known as the Durie-Salmon staging system. But today, doctors are more commonly using a newer system, called the International Staging System for Multiple Myeloma (ISS). The ISS has three stages, and uses factors such as the levels of proteins found in the blood to help classify each stage. Other important factors that may be important are kidney function, platelet count, and the patient’s age.

Treatment and Side Effects Management

There are several treatment options for multiple myeloma, and sometimes a combination of therapies may be used. Multiple myeloma cannot be cured, but therapies may help keep the cancer in remission.

People should get second opinions, talk through all of their options with their doctors and develop a treatment plan that best fits their needs. The treatment plan varies on how advanced the disease is, whether the person has symptoms, and on the person’s overall health status.

It is important to remember that these are general guidelines and that your doctor might suggest a treatment plan that differs from what is listed below. Do not hesitate to ask questions and be an active part of your treatment planning process.

It is important to note that it is common to use more than one treatment option at a time, as many therapies work together to treat the disease.

After a diagnosis of asymptomatic (smoldering myeloma) or multiple myeloma is made, treatment options can include:

  • Watchful waiting
  • Bisphosphonates
  • Chemotherapy
  • Radiation therapy
  • Stem cell transplant 
  • Targeted therapy
  • Biological therapy

Learn More About Treatment and Side Effects Management