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TNM staging system

Friday 5 July 2013

The TNM system describes 3 key pieces of information:

- T indicates the size of the main (primary) tumor and whether it has grown into nearby areas.
- N describes how much the cancer has spread to nearby (regional) lymph nodes. Lymph nodes are small bean-shaped collections of immune system cells to which cancers often spread.
- M indicates whether the cancer has spread (metastasized) to other organs of the body. (The most common site is the liver.)

Numbers or letters appear after T, N, and M to provide more details about each of these factors. The numbers 0 through 4 indicate increasing severity. The letter X means cannot be assessed because the information is not available.


- Blog: TNM Classification Help.