Myeloma: related conditions

Plasmacytoma is similar to myeloma but the abnormal plasma cells are only found in one area of the body. Because it affects a specific location, it is usually treated with radiotherapy.

Plasmacytoma can develop into “multiple” myeloma where more than one part of the body is affected.

Plasma cells are normally found in the bone marrow, not in the blood. This is also true in myeloma.

If blood tests show that there are plasma cells in the blood, you may get a diagnosis of plasma cell leukaemia (PCL). This may be primary PCL, where there’s been no previous evidence of myeloma, or secondary PCL, where the myeloma has progressed to PCL.

The treatments for PCL are generally the same treatments as for myeloma.

People with WM also have paraprotein in their blood. WM is a type of lymphoma and is not closely related to myeloma. It has different symptoms and treatment.

We have more information about the symptoms, diagnosis and treatment of WM.

Monoclonal gammopathy of undetermined significance or MGUS (pronounced em-gus) affects about three in every hundred people (3%) over the age of 50. If you have MGUS, your plasma cells produce a very small of paraprotein which can be detected in blood tests.

MGUS generally causes no symptoms and or damage to your body. So no treatment is needed and people aren’t routinely tested for it. It usually shows up by chance when you have a blood test for something else.

People with MGUS have a higher risk of developing myeloma, but it’s still low. Around one in a hundred people with MGUS (1%) go on to develop myeloma each year. Anyone with MGUS will have regular tests to check whether things are changing.

Even though MGUS doesn’t normally affect you physically, it can be worrying to know that you have a condition that could, in a small number of cases, lead to myeloma. You might find it helpful to read our information about MGUS and contact our Support Service if you have any questions about an MGUS diagnosis.

Around 10 to 15 people in every hundred diagnosed with myeloma (10%-15%) also develop a condition called amyloidosis. This is where the plasma cells make an abnormal protein called amyloid. Amyloid can damage in organs such as your kidneys, heart, spleen or gut over time, but not everyone is affected in this way.

Some people have amyloidosis but don’t have myeloma. It’s unusual for amyloidosis to develop into myeloma.

Treatment for myeloma also treats amyloidosis.

Myeloma UK has more information on amyloidosis.

Multiple myeloma is the same as myeloma. It is just another name for the same disease.

Some people call it "multiple myeloma" because myeloma affects the bone marrow in more than one place, and can affect other parts of the body.