Myeloma, also called multiple myeloma, is a type of blood cancer that develops from cells in the bone marrow called plasma cells. Multiple myeloma is a cancer formed by malignant plasma cells. Normal plasma cells are found in the bone marrow and are an important part of the immune system.
When plasma cells become cancerous and grow out of control, they can produce a tumor called a plasmacytoma. These tumors generally develop in a bone, but they are also rarely found in other tissues. If someone has only a single plasma cell tumor, the disease is called an isolated (or solitary) plasmacytoma. If someone has more than one plasmacytoma, they have multiple myeloma.
Multiple myeloma is an incurable blood cancer, characterized by a recurring pattern of remission and relapse. It is a rare and very aggressive disease that accounts for approximately one percent of all cancers. In the U.S., there are nearly 90,000 people living with, or in remission from, multiple myeloma. Approximately, 26,850 Americans are diagnosed with multiple myeloma each year and 11,240 patient deaths are reported on an annual basis.
|Classification and external resources|
|Synonyms||Plasma cell myeloma, myelomatosis, or Kahler's disease|
|Specialty||Hematology and oncology|
|Patient UK||Multiple myeloma|
Multiple myeloma (myelo- + -oma, "marrow" + "tumor"), is a cancer of plasma cells, a type of white blood cell normally responsible for producing antibodies. In multiple myeloma, collections of abnormal plasma cells accumulate in the bone marrow, where they interfere with the production of normal blood cells. Most cases of multiple myeloma also feature the production of a paraprotein—an abnormal antibody which can cause kidney problems. Bone lesions and hypercalcemia (high blood calcium levels) are also often encountered.
Multiple myeloma is diagnosed with blood tests (serum protein electrophoresis, serum free kappa/lambda light chain assay), bone marrow examination, urine protein electrophoresis, and X-rays of commonly involved bones.
Multiple myeloma is considered to be incurable but treatable. Remissions may be induced with steroids, chemotherapy, proteasome inhibitors, immunomodulatory drugs such as thalidomide or lenalidomide, and stem cell transplants. Radiation therapy is sometimes used to reduce pain from bone lesions.
Multiple myeloma develops in 6.1 per 100,000 people per year. It is more common in men and, for unknown reasons, is twice as common in African Americans as it is in White Americans. With conventional treatment, median survival is 3–4 years, which may be extended to 5–7 years or longer with advanced treatments. Multiple myeloma is the second most common hematological malignancy in the U.S. (after non-Hodgkin lymphoma), and constitutes 1% of all cancers. The five year survival rate is 45%.