Multiple Myeloma Risk Factors and Symptoms

Myeloma is a type of blood cancer that forms in plasma cells, which are located in the bone marrow. When healthy plasma cells change and grow out of control, it can result in multiple bone lesions, hence the name “multiple myeloma.” 

Learn more about the difference between bone cancer and multiple myeloma. 

The causes of multiple myeloma are unknown. Some people experience symptoms, while others experience no symptoms at all. Still, knowing what to look for and what could increase your risk can help catch multiple myeloma as early as possible, which makes it easier to treat.

Risk Factors for Developing Multiple Myeloma

If you have any of the following, you are at an increased risk of developing multiple myeloma:

  • Family history. First-degree relatives (parents, siblings, and children) of someone with multiple myeloma have a slightly increased risk of developing a similar condition.
  • Monoclonal gammopathy of undetermined significance (MGUS). MGUS is a condition in which an abnormal monoclonal, or M protein, is in the blood. Someone who has MGUS has a higher risk of developing multiple myeloma than someone who does not have this disease. 
  • Exposure to radiation or chemicals. People who have been exposed to radiation or to asbestos, benzene, pesticides, herbicides (including Agent Orange), and other chemicals used in rubber manufacturing may be at higher risk for developing myeloma. 

Other, less specific risk factors include:

  • Age. Most people who receive a multiple myeloma diagnosis are over the age of 60. Cases are very rare (only 2%) in people under the age of 40. 
  • Race. Myeloma occurs twice as frequently in black people as in white people. There is no known reason for this. 
  • Gender. The chance of developing multiple myeloma is slightly higher in men than women. 

Some people with several risk factors may never develop cancer, while others with no known risk factors do. It’s smart to know your risk factors in case you want to talk about them with your doctor or make more informed lifestyle and healthcare choices. 

Common Symptoms of Multiple Myeloma 

According to the International Myeloma Foundation, remembering the CRAB acronym can help make it easier to recognize the four most common signs and symptoms of multiple myeloma

  • C: high calcium levels (greater than 10 mg/dL)
  • R: renal (kidney) dysfunction
  • A: anemia
  • B: bone problems

An Increase in Blood Calcium

As bones become damaged, they can release calcium into the bloodstream. This condition of high calcium levels, called hypercalcemia, can result in symptoms such as mental confusion, constipation, dehydration, extreme thirst, weakness, fatigue, and renal or kidney damage. 

Renal Problems in Kidney Damage

When myeloma cells produce abnormal monoclonal proteins and release them into the bloodstream, they can pass into the urine, resulting in kidney damage. This causes symptoms including fatigue, mental confusion, and sluggish circulation. 


Anemia is a reduced number of red blood cells. This can lead to symptoms including weakness, a reduced ability to exercise, rapid heartbeat, swelling in legs, headache, chills, shortness of breath, changes in appetite, and dizziness.

Bone Damage

Myeloma cells activate osteoclast cells, which destroy the bone. They also block osteoblast cells, which repair damaged bone. This can lead to bone problems, such as swelling or tenderness in the limbs, bone pain, bone thinning (osteoporosis), and bone fractures that aren’t associated with a significant injury. In some cases, nerve or spinal cord damage may occur. 

If you have concerns about your risk factors or are experiencing symptoms like the ones above, please consult your doctor. Your doctor can discuss what tests may be needed to learn more about the cause of your symptoms to make a diagnosis. Learn more about how doctors detect and diagnose multiple myeloma.