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What You Need To Know About™ Multiple Myeloma
    Posted: 11/20/2008
What is Multiple Myeloma?

Normal Blood Cells
Myeloma Cells

Multiple myeloma is a type of cancer. Cancer is a group of many related diseases. Myeloma is a cancer that starts in plasma cells, a type of white blood cell. It's the most common type of plasma cell cancer.

Normal Blood Cells

Most blood cells develop from cells in the bone marrow called stem cells. Bone marrow is the soft material in the center of most bones.

Stem cells mature into different types of blood cells. Each type has a special job:

  • White blood cells help fight infection. There are several types of white blood cells.
  • Platelets help form blood clots that control bleeding.

Plasma cells are white blood cells that make antibodies. Antibodies are part of the immune system. They work with other parts of the immune system to help protect the body from germs and other harmful substances. Each type of plasma cell makes a different antibody.

Normal plasma cells help protect the body from germs and other harmful substances. Normal plasma cells help protect the body from germs and other harmful substances.

Myeloma Cells

Myeloma, like other cancers, begins in cells. In cancer, new cells form when the body doesn't need them, and old or damaged cells don't die when they should. These extra cells can form a mass of tissue called a growth or tumor.

Myeloma begins when a plasma cell becomes abnormal. The abnormal cell divides to make copies of itself. The new cells divide again and again, making more and more abnormal cells. These abnormal plasma cells are called myeloma cells.

In time, myeloma cells collect in the bone marrow. They may damage the solid part of the bone. When myeloma cells collect in several of your bones, the disease is called "multiple myeloma." This disease may also harm other tissues and organs, such as the kidneys.

Myeloma cells make antibodies called M proteins and other proteins. These proteins can collect in the blood, urine, and organs.

Myeloma cell (abnormal plasma cell) making M proteins. Myeloma cell (abnormal plasma cell) making M proteins.


Dictionary Terms

antibody (AN-tee-BAH-dee)
A protein made by plasma cells (a type of white blood cell) in response to an antigen (a substance that causes the body to make a specific immune response). Each antibody can bind to only one specific antigen. The purpose of this binding is to help destroy the antigen. Some antibodies destroy antigens directly. Others make it easier for white blood cells to destroy the antigen.
bone marrow (bone MAYR-oh)
The soft, sponge-like tissue in the center of most bones. It produces white blood cells, red blood cells, and platelets.
immune system (ih-MYOON SIS-tem)
The complex group of organs and cells that defends the body against infections and other diseases.
infection
Invasion and multiplication of germs in the body. Infections can occur in any part of the body and can spread throughout the body. The germs may be bacteria, viruses, yeast, or fungi. They can cause a fever and other problems, depending on where the infection occurs. When the body’s natural defense system is strong, it can often fight the germs and prevent infection. Some cancer treatments can weaken the natural defense system.
M protein (... PROH-teen)
An antibody found in unusually large amounts in the blood or urine of people with multiple myeloma and other types of plasma cell tumors. Also called monoclonal protein.
platelet (PLATE-let)
A tiny piece of a cell found in the blood that breaks off from a large cell found in the bone marrow. Platelets help wounds heal and prevent bleeding by forming blood clots. Also called thrombocyte.
red blood cell
A cell that carries oxygen to all parts of the body. Also called erythrocyte and RBC.
stem cell
A cell from which other types of cells develop. For example, blood cells develop from blood-forming stem cells.
tissue (TISH-oo)
A group or layer of cells that work together to perform a specific function.
tumor (TOO-mer)
An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancer), or malignant (cancer). Also called neoplasm.