Breast cancer (staging)

Breast cancer staging uses the TNM staging system and then into stage groupings.

Classification

TNM staging

Primary tumor (T)

• Tx: primary tumor cannot be assessed
• T0: no evidence of primary tumor
• Tis: carcinoma in situ
• T1
  • T1a: 0.1-0.5 cm
  • T1b: 0.5-1.0 cm
  • T1c: 1.0- 2.0 cm
• T2: 2-5 cm
• T3: >5 cm
• T4: any size 
  • T4a: chest wall fixation no edema 
  • T4b: edema (peau d'orange change) or satellite skin nodules
  • T4c: T4a and T4b
  • T4d: inflammatory breast cancer

Nodal status (N)

• Nx: nodes cannot be assessed
• N0: no evidence of nodal involvement
• N1: mobile axillary lymph nodes
• N2: fixed/matted axillary lymph nodes or ipsilateral internal mammary artery lymph nodes
• N3: (a) infraclavicular (b) ipsilateral IMA and axilla (c) supraclavicular

Metastases (M)

• Mx: presence of metastases cannot be assessed
• M0: no evidence of metastases
• M1: distant metastases present

AJCC stage groupings

• stage 0
  • Tis, N0, M0 
• stage I
  • T1, N0, M0
• stage IIA
  • T0, N1, M0
  • T1, N1, M0
  • T2, N0, M0
• stage IIB
  • T2, N1, M0
  • T3, N0, M0
• stage IIIA
  • T0-2, N2, M0
  • T3, N1-2, M0
• stage IIIB
  • T4, N0-2, M0
• stage IIIC
  • T0-4, N3, M0
• stage IV
  • T0-4, N0-3, M1

Treatment and prognosis:

Estimated five year survival rates:

• stage I: ~87% 
• stage II: ~75%  
• stage III: ~46%  
• stage IV: ~13%  

See also

• breast cancer