What is multiple myeloma?
Multiple myeloma is a cancer that develops in a type of plasma cell called a white blood cell. Plasma cells help you combat infections by producing germ detecting and destroying antibodies. The bone marrow contains natural plasma cells and is an integral part of the immune system. The immune system consists of several cell types which work together to fight infections and other diseases. In the immune system, lymphocytes are one of the largest groups of white blood cells which include T cells which B cells. There are lymphocytes in many areas of the body including lymph nodes, bone marrow, intestines and bloodstream.
As B cells respond to an infection, they actually grow and turn into plasma cells. Plasma cells produce the antibodies that help the body target and destroy germs. Plasma cells are mainly found in the bone marrow. Aside from plasma cells, normal bone marrow is also the home for other blood cells including red cells, white cells, and platelets.
In general, multiple myeloma is when the plasma cells become cancerous and develop out of control. The plasma cells make an abnormal protein known by different names including monoclonal immunoglobulin, monoclonal protein (M-protein), M-spike, or paraprotein. As multiple myeloma worsens, the plasma cells spill out and spread from the bone marrow. This causes more damage to organs.
Causes
What causes multiple myeloma?
The multiple myeloma causes are not clear. Myeloma begins with one abnormal plasma cell in the bone marrow which is easy to multiply. Since cancer cells don’t grow and then die like normal cells do, they multiply overwhelming the healthy cell development eventually. Myeloma cells crowd out healthy white blood cells and red blood cells in the bone marrow resulting in weakness and an inability to combat infections.
Like healthy plasma cells do, the myeloma cells continue to try to produce antibodies but the myeloma cells produce irregular antibodies that the body cannot use. Alternatively, the abnormal antibodies build up in the body and cause complications including kidney damage. Cancer cells can also cause bone damage which increases the risk of broken bones.
Multiple myeloma starts out as a benign condition called monoclonal gammopathy of undetermined significance (MGUS). MGUS is identified by the presence of M proteins – produced by abnormal plasma cells in the blood. However, in MGUS, the levels of M proteins are low and there is no damage to the body.