TNM Staging
Also known as: TNM, TNM system
The international system that describes cancer by tumour size (T), node involvement (N) and metastasis (M).
Definition
The TNM system is the international standard for describing the anatomical extent of most solid cancers. It uses three letters: T for the size and local extent of the primary tumour; N for involvement of regional lymph nodes; and M for distant metastasis. Each letter is given a number (for example T2 N1 M0).
The T, N and M values are combined into an overall stage from I (early, localised) to IV (widespread). TNM staging is decided after imaging, biopsy and, where relevant, surgery, and it is the foundation on which treatment decisions and prognosis are built.
See also
- Staging — The process of finding out how large a cancer is and whether it has spread.
- Metastasis — Cancer that has spread from where it started to another part of the body.
- Lymph Node — Small bean-shaped immune organs that filter lymph fluid and often show the first signs of cancer spread.
- Prognosis — A doctor's best estimate of how a cancer is likely to behave and respond to treatment.
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Medically reviewed by
Dr. Rehan Abdullah
Dr. Rehan Abdullah is a dual-trained clinical and radiation oncologist with over a decade of experience treating both solid tumours and hematologic malignancies. He serves as Consultant Oncologist at INMOL Hospital and sees patients at Farooq Hospital and Healthnox Medical Center, Lahore. Read full profile →
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