TNM classification (Tumor, Nodal and Metastasis
classification)
of The American Joint Committee on Cancer (AJCC)
Primary tumor (T)
The definitions for classifying the primary tumor (T) are the same for
clinical and for pathological classification. The telescoping method of
classification can be applied. If the measurement is made by physical examination,
the examiner will use the major headings (T1, T2, or T3). If other measurements,
such as mammographic or pathologic are used, the telescoped subsets of T1
can be used.
TX - primary tumor cannot be assessed
T0 - no evidence of primary tumor
Tis - carcinoma in situ, intraductal carcinoma,
lobular carcinoma
in situ, or Paget's disease of the nipple with no tumor.
T1 - Tumor is 2cm or less in the greatest dimension.
- T1mic - Microinvasion 0.1 cm or less in greatest dimension
- T1a - 0.5cm or less in the greatest dimension.
- T1b - More than 0.5cm, but not more than 1cm in the greatest dimension.
- T1c - More than 1cm but not more than 2cm in the greatest dimension.
T2 - Tumor is more than 2cm but not
more than 5cm in the greatest dimension.
T3 - Tumor is more than 5cm in the greatest
dimension.
T4 - Tumor of any size with direct extension
to the chest wall or skin.
- T4a - Extension to the chest wall.
- T4b - Edema (including peau d'orange) or ulceration of the skin of
the breast or satellite skin nodules confined to the same breast.
- T4c - Both T4a and T4b.
- T4d - Inflammatory carcinoma.
Regional Lymph Nodes (N)
NX - Regional lymph nodes cannot
be assessed (e.g. previously removed).
N0 - No regional lymph node
metastasis.
N1 - Metastasis to movable
ipsilateral axillary lymph node(s).
N2 - Metastasis to ipsilateral
axillary lymph node(s) fixed to one another or to other structures.
N3 - Metastasis to ipsilateral
internal mammary lymph node(s).
Distant Metastasis (M)
MX - Presence of distant
metastasis cannot be assessed.
M0 - No distant
metastasis.
M1 - Distant metastasis
(includes metastasis to ipsilateral supraclavicular lymph node(s)).
Breast Cancer Stage Grouping
|
|
Tumor
|
Nodes
|
Metastasis
|
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 |
N2 |
M0 |
|
T1* |
N2 |
M0 |
|
T2 |
N2 |
M0 |
|
T3 |
N2 |
M0 |
|
T3 |
N1,N2 |
M0 |
Stage IIIB
|
T4 |
Any N |
M0 |
|
Any T |
N3 |
M0 |
Stage IV
|
Any T |
Any N |
M1 |
|
*T1 includes T1mic
|