Multiple myeloma is a type of cancer that affects plasma cells, white blood cells that produce antibodies to help the body ward off infection. Plasma cells are primarily located in bone marrow but are found in other tissues and organs as well. Multiple myeloma occurs when plasma cells change and stop behaving normally. These abnormal plasma cells divide uncontrollably, creating more abnormal plasma cells. This uncontrolled cell growth causes cancer when the abnormal plasma cells take over the bone marrow and prevent normal blood cells from developing and functioning. The cause of multiple myeloma remains a mystery, but there are risk factors for developing the disease.
Older adults are more susceptible to developing multiple myeloma. The disease is more common in individuals over sixty years old, and the average age at diagnosis is seventy years old. Very few cases, only two percent, occur in individuals under forty years old. This can be compared to the twelve percent of patients with leukemia, the eight percent of patients with non-Hodgkin's lymphoma, and the thirty-six percent with Hodgkin's lymphoma under the forty years old. Studies have shown the number of cases of multiple myeloma among seniors is rising, but the reason for this increase is unknown. Older patients are generally more difficult to treat than patients in their forties because older adults tend to develop multiple illnesses by the time they approach the eighty-year mark. Death from multiple myeloma tends to be more common among the elderly.