Multiple myeloma, sometimes just called myeloma, is a form of cancer which affects plasma cells. These are a type of white blood cell made in the bone marrow. Bone marrow, where most blood cells are made, is the 'spongy' material found in the centre of the larger bones in the body. Normal plasma cells produce antibodies, also called immunoglobulins, to help fight infection.
In myeloma, these plasma cells become abnormal, multiply uncontrollably and release only one type of antibody, known as paraprotein, which has no useful function. It is often through the measurement of paraprotein that myeloma is diagnosed and monitored.
Myeloma affects many places in the body (thus 'multiple' myeloma) where bone marrow is normally active in an adult. For example, in the bones of the spine, skull, pelvis, shoulder blades, rib cage and the long bones of the arms and legs.
Unlike many cancers, myeloma does not exist as a lump or tumour. Most of the medical problems related to myeloma are caused by the build-up of the abnormal plasma cells in the bone marrow and the presence of the paraprotein in the blood or urine.
Myeloma symptoms are initially relapsing and remitting. This means there are periods when the myeloma is causing symptoms and/or complications and needs to be treated, followed by periods of remission or plateau where the myeloma does not cause symptoms and does not need treatment.
How common is it?
It is the second most common form of blood and bone marrow cancer, but accounts for only 1% of all cancers in the UK.
About 5,000 people are diagnosed with multiple myeloma each year in the UK.
About 1 in 120 men and 1 in 155 women will develop myeloma at some time in their life.
It mainly occurs in people over 60 years old, although people under 60 and, more rarely, under 40 can be affected. It is slightly more common in men than in women and is twice as common in the African-Caribbean population as in Caucasian people. The most common age at which people are diagnosed with myeloma is about 72.
What are the symptoms?
In the early stages, myeloma may not cause any symptoms. It is often only suspected or diagnosed after a routine blood or urine test. Eventually, myeloma will cause a range of problems, including:
- A persistent dull ache or specific areas of tenderness in your bones
- Weak bones that break (fracture) easily
- Anaemia (lack of red blood cells), which can cause tiredness, weakness and shortness of breath
- Repeated infections
- Less commonly, bruising and unusual bleeding - such as frequent nosebleeds, bleeding gums and heavy periods
- Raised calcium levels in the blood (hypercalcaemia) - this can cause thirst, nausea, vomiting, confusion and/or constipation
- Thickened blood - in some people, multiple myeloma can cause the blood to become thicker than normal (hyperviscosity), which can cause blurred vision, headaches, dizziness, bleeding from the gums or nose, and shortness of breath.