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Multiple Myeloma


The Manual's Editorial Staff

Reviewed/Revised May 2022 | Modified Sep 2022
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  • Red blood cells carry oxygen

  • White blood cells fight infection

  • Platelets help your blood clot when you're bleeding

Plasma cells are a special type of white blood cell. Plasma cells make antibodies. Antibodies are proteins that are part of your body's natural defenses against infections and cancer. Antibodies find and attack foreign cells.

Bone marrow is in the center of your bones. Most of the cells in your blood are made in your bone marrow. The different blood cells all develop from what's called a stem cell.

What is multiple myeloma?

Multiple myeloma is a cancer of plasma cells. One of your plasma cells multiplies out of control in your bone marrow and makes many copies of itself.

  • Multiple myeloma often causes bone pain, fractures, and kidney failure

  • The average age of people with multiple myeloma is about 65

  • Doctors do blood and urine tests and a bone marrow biopsy (remove a sample of the bone marrow to look at under a microscope) to diagnose multiple myeloma

  • Doctors usually treat the cancer with chemotherapy, corticosteroids, and sometimes a stem cell transplant

How does multiple myeloma cause problems?

The cancerous plasma cells:

  • Invade nearby healthy bone

  • Crowd out the normal cells in your bone marrow

  • Produce a lot of one kind of antibody

Bone invasion makes your bones hurt and more likely to break.

When the abnormal cells take over your bone marrow, you don't make enough normal blood cells. Without enough red blood cells, you get anemia Overview of Anemia Anemia is not having enough red blood cells or hemoglobin. Red blood cells carry oxygen from your lungs to all of your other organs. Hemoglobin is the substance inside your red blood cells that... read more (low blood count). Without enough healthy white cells, you're at risk for infections. Without enough platelets, you may have excessive bleeding.

The extra antibody made by the cancerous plasma cells is abnormal and doesn't help protect you from infection. However, it can clog up your kidneys and give you kidney failure.

What causes multiple myeloma?

Doctors don’t know what causes multiple myeloma, but they think it may:

  • Run in families

  • Sometimes happen from being around too much radiation or certain chemicals

What are the symptoms of multiple myeloma?

The most common symptom is:

  • Pain in your bones, usually your hips, spine, ribs, and skull

You may have other symptoms from complications:

  • Feeling tired and weak due to anemia (low blood count)

  • Infections that cause fever and chills

  • Unusual bruising and bleeding due to problems with your blood clotting

How can doctors tell if I have multiple myeloma?

Doctors will do:

If these tests show you might have multiple myeloma, doctors will do:

  • Bone marrow biopsy (remove a sample of the bone marrow to look at under a microscope)

  • X-rays of all the bones in your body (skeletal survey) to see which ones are affected by myeloma

How do doctors treat multiple myeloma?

Doctors will treat you to help slow the cancer’s growth and relieve your symptoms. They can’t cure multiple myeloma, but you may survive for a long time.

Doctors may give you:

  • They take some healthy stem cells from you, or less often another person

  • Then they give you strong chemotherapy to wipe out your abnormal plasma cells

  • Then they give you back the healthy stem cells through a vein (IV)

  • These stem cells go to your bone marrow where they can produce normal blood cells

Doctors are doing fewer stem cell transplants because the newer drugs for multiple myeloma work fairly well.

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