What are the risk factors?

The causes of myeloma are not known. We know that plasma cells become cancerous when there are certain changes in their DNA. DNA is found in all cells. It carries instructions that control how cells work. However, we do not yet know what causes DNA to change.

Risk factors for myeloma include:

• exposure to certain chemicals (dioxins used in industry);
•  high levels of radiation; and
•  the human immunodeficiency virus (HIV).

These factors have been linked to an increased risk, but they have not been proven to cause it.

People with monoclonal gammopathy of undetermined significance (MGUS) are more likely to develop myeloma.