What Is Multiple Myeloma?

Multiple myeloma is cancer that affects certain white blood cells called plasma cells. It represents about 1% of all cancers in the United States, and about four to five out of every 100,000 people are diagnosed with it each year.

What happens when someone develops multiple myeloma?

To help understand what is happening when someone has cancer, it helps to understand how the body works normally. The human body is made up of tiny building blocks called cells. Normal cells grow and multiply when the body needs them, and die out when the body does not need them.

Cancer is made up of abnormal cells that grow whether or not they are needed. Multiple myeloma is cancer that begins in the plasma cells. These are a type of white blood cell.

Plasma cells make proteins that help the body fight disease. These cells are in the soft inner part of our bones, called the bone marrow. Multiple myeloma starts when plasma cells become abnormal. It's also known as myeloma or plasma cell myeloma.

White blood cells originate in bone marrow, some of which become antibody-producing plasma cells as seen in the top part of the drawing.

Cancerous plasma cells are called myeloma cells. Myeloma cells crowd normal bone marrow, so there is not enough room for the bone marrow to make as many healthy cells. Several kinds of blood problems may result.

  • Low red blood cell count. This condition is called anemia. It is identified by a blood test. It can cause tiredness as well as other problems.
  • Low white blood cell count. This condition is neutropenia. It weakens the body's defenses against infection.
  • Low platelet count. This condition is called thrombocytopenia. It may lead to bleeding.
    Although this cancer starts in blood cells, it also has a big effect on bones. Myeloma cells can harm the bone structure. Bones may become weak and more likely to break.

Because they destroy bone, myeloma cells can cause stored calcium from the bone to be released into the bloodstream. This can lead to too much calcium in the blood, called hypercalcemia. Hypercalcemia can harm the heart, nerves, and kidneys. These are some signs of hypercalcemia.

  • Constipation
  • Fatigue
  • Frequent urination
  • Frequent thirst
  • Muscle weakness

Myeloma can also affect the kidney. Myeloma cells make large amounts of abnormal proteins called M-proteins. These M-proteins circulate in the blood and can overwork the kidneys, so they can not function properly.

Clinical Trials

Clinical trials are research studies that evaluate a new medical approach, device, drug, or other treatment. As a Stanford Health Care patient, you may have access to the latest, advanced clinical trials.

Open trials refer to studies currently accepting participants. Closed trials are not currently enrolling, but may open in the future.

Before beginning treatment, ask your doctor about any clinical trials you should consider. Learn more about clinical trials for cancer patients.

Clinical trial eligibility flowcharts

Eligibility flowcharts map clinical trials to specific types of cancers to determine if a participant is eligible for the particular clinical trial. View all hematology eligibility flowcharts at the Stanford Cancer Institute.

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