Multiple myeloma (MM), also known as plasma
cell myeloma and simply myeloma, is a cancer of plasma cells, a type of white
blood cell that normally produces antibodies. Often no symptoms are noticed
initially. As it progresses, bone pain, anemia, kidney dysfunction, and
infections may occur. Complications may include amyloidosis.
The cause of multiple myeloma is unknown.
Risk factors include obesity, radiation exposure, family history, and certain
chemical. Multiple myeloma may develop from monoclonal gammopathy of
undetermined significance that progresses to smoldering myeloma. The abnormal
plasma cells produce abnormal antibodies, which can cause kidney problems and
overly thick blood. The plasma cells can also form a mass in the bone marrow or
soft tissue. When one tumor is present, it is called a plasmacytoma; more than
one is called multiple myeloma. Multiple myeloma is diagnosed based on blood or
urine test finding abnormal antibodies, bone marrow biopsy finding cancerous
plasma cells, and medical imaging finding bone lesions. Another common finding
is high blood calcium levels.
Multiple myeloma is considered treatable, but
generally incurable. Remissions may be brought about with steroids,
chemotherapy, targeted therapy and stem cell transplant. Bisphosphonates and
radiation therapy are sometimes used to reduce pain from bone lesions.