Myeloma is a type of blood cancer that develops from cells in the bone marrow called plasma cells. Bone marrow is the spongy tissue found inside the inner part of some of our large bones. The bone marrow produces different types of blood cells.
What are plasma cells?
Plasma cells are part of the immune system. Normal plasma cells make proteins called antibodies. These antibodies are also called immunoglobulins.
The plasma cells make antibodies when the body responds to infections. They make different antibodies for different infections. Antibodies attack and help to kill bacteria and viruses and so protect us from infections.
There are 5 main types of antibody (immunoglobulin) – A, G, M, D and E.
How does myeloma develop?
Myeloma develops when there is a change in the DNA of the plasma cells. DNA is the instructions for the cell so it knows what to do and when. The change happens to the DNA when the bone marrow is making new plasma cells. The abnormal plasma cell then produces more abnormal cells. These are myeloma cells.
The myeloma cells produce an abnormal form of one of the types of antibody. You might hear your doctor call the antibodies abnormal proteins, paraproteins, monoclonal proteins, or a monoclonal spike. They aren't able to work normally and so can't help fight infections.
The paraprotein is often found in the blood and urine if you have myeloma. Blood and urine tests are a way of diagnosing and monitoring myeloma. As well as the whole antibody (immunoglobulin), often a small part called the free light chain (called Bence-Jones in the urine) is also made in large amounts by the myeloma plasma cells.
Myeloma doesn't form a lump or a tumour. Most of the problems it causes are because of a build up of abnormal plasma cells in the bone marrow and the paraprotein in the body. Myeloma affects areas where you have active bone marrow. This includes your arms and legs and your shoulders as well as your spine, skull, pelvis and rib cage. Myeloma affects several places in the body which is why it is sometimes called multiple myeloma.
This video is about myeloma. It lasts for 2 minutes and 58 seconds.
What is Myeloma?
Myeloma is a type of blood cancer that develops from plasma cells in the bone marrow. Bone marrow is the spongy tissue found inside the inner part of some of our large bones.
0.16 It makes different types of blood cells. All blood cells start as the same type of call called a stem cell. These develop into red cells, white cells and platelets.
0.31 There are several types of white blood cells. Some white blood cells, called B-lymphocytes develop to form plasma cells. They’re an important part of the immune system.
0.43 Normal plasma cells make proteins called antibodies, also known as immunoglobulins. These antibodies help the body to fight infections.
0.54 Myeloma starts when there’s a mistake with the bone marrow making plasma cells. These abnormal plasma cells are myeloma cells. They divide to make more myeloma cells.
1.09 Myeloma cells make abnormal types of antibodies called paraproteins or monoclonal proteins. These abnormal antibodies don’t work. Myeloma reduces the number of normal immune cells and normal antibodies. This is why people with myeloma get more infections.
1.29 The large amount of the abnormal antibodies or paraproteins can thicken the blood. This can make you feel dizzy or have headaches.
1.39 The myeloma cells also crowd the bone marrow leaving little space for other types of blood cells.
1.46 Red blood cells contain haemoglobin. They carry oxygen around the body. When there are fewer red blood cells you become anaemic. This means you feel tired and might be breathless.
2.02 Myeloma cells can build up anywhere in the body. This is why it’s also called multiple myeloma.
2.09 Myeloma cells can also damage and break down nearby bones. This can cause pain and the release of calcium into the bloodstream which causes high calcium levels. High calcium levels cause symptoms including feeling thirsty, constipated or confused.
2.29 Myeloma cells can also damage the kidneys.
2.32 Information about your symptoms helps your specialist plan the best treatment for you. Find out more about treatment at cruk.org/myeloma
Blood cells and myeloma
To understand why myeloma affects you the way it does, it helps to understand how blood cells are normally produced and what they do.
Usually bone marrow makes blood cells in a controlled way, when your body needs them. All blood cells start as the same type of cell, called a stem cell. As they develop (mature), they turn into one of three types of blood cell:
- white blood cells (leucocytes)
- red blood cells (erythrocytes)
- platelets (thrombocytes)
Plasma cells develop from a type of white blood cell called B lymphocytes. In myeloma, too many plasma cells are made and they are all of the same type. They crowd the bone marrow. This means that there is not enough space for making normal white cells, red cells and platelets.
What do your blood cells do?
The white cells are important for fighting infection. If you don't have enough white blood cells, you will pick up more infections, and infections might take longer to get better.
Red blood cells carry oxygen round the body. If you haven't got enough red blood cells, you have anaemia. This can make you tired and breathless.
Platelets are important for normal blood clotting. If you don't have enough platelets, you might bleed more. You might have nosebleeds, very heavy periods, or a fine rash of red spots caused by bleeding into the skin.
How common is myeloma?
Around 6,000 people are diagnosed with myeloma in the UK each year. That is 16 people every day.
Who gets it?
Myeloma is more common in men than women.
It is more common in older people. In the UK, on average each year around 45 out of 100 (around 45%) of new cases are in people aged 75 and over. It is very rare in people younger than 40.