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What is thymus cancer?

  1. Home
  2. Cancer information
  3. Cancer types
  4. Thymus
  5. What is thymus cancer
Print

Thymus cancer starts in the cells of the thymus. A cancerous (malignant) tumour is a group of cancer cells that can grow into and destroy nearby tissue. It can also spread (metastasize) to other parts of the body. Cancerous tumours of the thymus are rare.

The thymus is a small gland in the top part of the chest between the lungs and under the breastbone. It makes T cells (T lymphocytes) that travel throughout the body to help fight infection, disease and foreign substances. The thymus also makes hormones and other substances to help T cells develop and keep the immune system working properly.

Diagram of the location of the thymus
Diagram of the location of the thymus

Cells of the thymus sometimes change and no longer grow or behave normally. These changes may lead to non-cancerous (benign) tumours such as thymic cysts and thymolipomas.

In some cases, changes to thymus cells can cause thymus cancer. Most often, thymus cancer starts in the epithelial cells of the thymus. These types of thymus cancer are called thymoma and thymic carcinoma.

Thymus cancer can also start in other types of cells, such as thymic neuroendocrine tumours (NETs).

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