TNM staging system

The TNM system is a cancer staging system published by the American Joint Committee on Cancer and has been widely adopted in many areas as a replacement for idiosyncratic disease-specific systems. The precise details depend on the primary tumor site and/or histology but in general:

  • Tx: primary tumor cannot be assessed
  • T0: no evidence of primary tumor
  • Tis: carcinoma in situ
  • T1: site/tumor specific, generally small
  • T2: site/tumor specific
  • T3: site/tumor specific, generally large
  • T4: site/tumor specific, generally direct extension into adjacent organs/tissues
  • Nx: nodes cannot be assessed
  • N0: no regional nodal metastasis
  • N1: site/tumor specific
  • N2: site/tumor specific
  • N3: site/tumor specific
  • M0: no distant metastasis
  • M1: distant metastasis present

The TNM system has been expanded to include other measures:

  • R: resection status
  • V: vascular invasion

Additional prefixes can be apended to define the TNM stage:

  • c: clinical assessment data
  • p: pathological data
  • y: clinical (yc) or pathological (yp) data following systemic or radiation therapy be it prior to surgery or as a primary treatment
  • r: clinical or pathological staging at the time of retreatment for recurrence or disease progression
  • a: autopsy data
  • m: multiple primary tumors, e.g. T2(m) or T2(5)

Whereas T, N, and M, are called categories, the stage refers to a grouping of TNM designations that have similar prognosis. Stages are numbered I though IV. In general, stage IV indicates M1 disease.

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Article information

rID: 2140
System: Oncology
Section: Staging
Synonyms or Alternate Spellings:
  • TNM staging
  • TNM

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