Myeloma begins when a plasma cell becomes abnormal and begins to divide uncontrollably, making more and more abnormal plasma cells. Abnormal plasma cells are called myeloma cells. Over time, the myeloma cells crowd out the normal blood cells in the bone marrow and prevent them from working properly. myeloma cells can also spread to the solid part of the bone and cause pain or fractures. As the number of myeloma cells increases, they can upset the balance of certain minerals in the body, such as calcium. They can also prevent organs, such as the kidneys and nerves, from working properly.
The disease is called multiple myeloma because it affects many bones. If myeloma cells form a tumour in only one bone, it’s called a plasmacytoma.
It was estimated that in 2021, Canada would see 3,800 new cases of multiple myeloma and 1,600 deaths from the disease.1