TNM staging of breast cancer

Last reviewed 06/2023

  • T0 - no evidence of primary tumour
  • T1 - the tumour is 2 cm or less in diameter, with no skin involvement - except in the case of Paget's disease where confined to the nipple - and no nipple retraction or fixation
  • T2 - tumour greater than 2 cm but less than 5 cm
  • T3 - tumour greater than 5 cm in greatest diameter, less than 10 cm
  • T4 - greater than 10 cm or skin or chest wall involvement or peau d'orange
  • N0 - no palpable ipsilateral axillary nodes
  • N1 - palpable, ipsilateral axillary nodes
  • N2 - ipsilateral axillary nodal metastases fixed to one another or to other structures
  • N3 - metastases to ipsilateral internal mammary nodes
  • M0 - no evidence of metastases
  • M1 - distant metastases (includes ipsilateral supraclavicular nodes)