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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 your 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.

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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. Thymus cancer usually starts in the epithelial cells of the thymus. These types of thymus cancer are called thymoma and thymic carcinoma.

A very rare cancer can start in the neuroendocrine cells of thymus. This type of tumour is called a thymic neuroendocrine tumour (NET).

Expert review and references

  • Martini FH, Tallitsch RB, Nath JL. Human Anatomy. 9th ed. New York, NY: Pearson; 2018.
  • Macmillan Cancer Support. Thymus Cancer. 2023. https://www.macmillan.org.uk/.
  • Remien K, Jan A. Anatomy, head and neck, thymus. StatPearls [Internet]. July 24, 2023.
  • Cameron RB, Girard N, Lee PP. Neoplasms of the mediastinum. DeVita VT Jr, Lawrence TS, Rosenberg S. eds. DeVita Hellman and Rosenberg's Cancer: Principles and Practice of Oncology. 12th ed. Philadelphia, PA: Wolters Kluwer; 2023: Kindle version, [chapter 32], https://read.amazon.ca/?asin=B0BG3DPT4Q&language=en-CA.

The thymus

The thymus is a gland in the upper part of the chest. It is part of the endocrine system and the lymphatic system.
Learn more on The thymus

Cancerous tumours of the thymus

Thymus cancer is rare. The most common types of thymic tumours are thymoma and thymic carcinoma.
Learn more on Cancerous tumours of the thymus

Non-cancerous tumours of the thymus

Non-cancerous tumours of the thymus are rare. Types include thymic cyst, thymolipoma and thymic hyperplasia.
Learn more on Non-cancerous tumours of the thymus

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