Multiple Myeloma Information
Learn More About Multiple Myeloma: Chat with Us | Email Us
What is Multiple Myeloma?
Multiple myeloma (also called Kahler disease or plasma cell myeloma) is a type of cancer that begins in the blood's plasma cells. Made in the bone marrow (the soft, inner part of some bones), plasma cells are a type of white blood cell (B lymphocyte) that produces antibodies (e.g., monoclonal proteins or M-proteins) which fight infection.
Multiple myeloma causes an excess of abnormal plasma cells (myeloma cells), which form tumors in multiple locations throughout the bone marrow. These tumors begin to overcrowd the bone marrow and prevent normal reproduction of healthy blood cells.
Understanding Multiple Myeloma
There are many kinds of cells that make up our blood, including red blood cells (RBCs), white blood cells (WBCs) and platelets. A particular category of WBCs, called lymphocytes, are a vital part of our immune defense.
There are two main types of lymphocytes, B lymphocytes (B cells) and T lymphocytes (T cells), both of which originate in the bone marrow. As the B cells mature, some develop into plasma cells. Plasma cells help the body’s immune system fight disease by producing antibody proteins in response to bacterial infections or viruses.
When malignant plasma cells (or myeloma cells) collect in only one bone and form a single mass or tumor, it is called a plasmacytoma. In most cases, however, the myeloma cells grow out of control and collect in many bones, often forming many tumors. When this happens, the disease is called multiple myeloma.
There are different types and subtypes of multiple myeloma, which are based on the type of immunoglobulin (protein) produced by the myeloma cell.
Although multiple myeloma affects the bones, it begins in cells of the bone marrow. Therefore, multiple myeloma is different from bone cancer, which begins in cells that form the hard, outer part of the bone.
Multiple Myeloma Incidence
Although it only accounts for one percent of overall cancers, multiple myeloma is the second most prevalent blood cancer after non-Hodgkin lymphoma. The International Myeloma Foundation reports that each year there are approximately 20,000 new cases of myeloma in the United States. This represents approximately 20 percent of blood cancers, and 1 percent of all types of cancer.
Multiple myeloma is more common in African Americans than white Americans, with a male/female ratio of 3 to 2. The incidence also rises with age. The average age at diagnosis is 60 and people under 40 rarely develop the disease.
Next Topic: Multiple Myeloma Risk Factors


