Myeloma, also known as multiple myeloma, is a cancer of plasma cells (a type of blood cell) that arises in the bone marrow (the soft tissue inside bones where blood cells are made).

Micrograph of myeloma neoplasm from bone marrow biopsy
Multiple MyelomaThe malignant plasma cells produce different substances that cause the bone to become thin, weak and more likely to break.

The plasma cells in healthy people are an important part of the immune system and develop from white blood cells called lymphocytes. These cells make antibodies that help fight infections.

When a person has multiple myeloma, there is a large increase in the malignant (cancerous) plasma cells and a reduction in the normal cells. The malignant plasma cells are inside the bone marrow. This means that there is no longer the space necessary to make normal white cells, red cells and platelets.

As a result, the person has fewer red and white cells. The low red cell count causes anaemia (with symptoms such as tiredness, lethargy and shortness of breath on exertion). The low white cell count may mean the person is less able to fight infections.

Multiple myeloma spreads from the bone marrow into the bone. The malignant plasma cells produce different substances that cause the bone to become thin, weak and more likely to break. This may be associated with an increase in the level of calcium in the blood (hypercalcaemia). Abnormal proteins produced by the malignant cells may affect the kidneys so that they cannot filter and clean the blood properly.

Symptoms of Myeloma

  • Bone lesions leading to pain and fractures
  • Anaemia and fatigue
  • Kidney damage leading to renal failure
  • Recurrent and /or persistent infections