Primary tumor (T) |
T1 | Tumor ≤3 cm diameter, surrounded by lung or visceral pleura, without invasion more proximal than lobar bronchus* |
T1a | Tumor ≤2 cm in diameter |
T1b | Tumor >2 cm but ≤3 cm in diameter |
T2 | Tumor >3 cm but ≤7 cm, or tumor with any of the following features: |
Involves main bronchus, ≥2 cm distal to carina |
Invades visceral pleura |
Associated with atelectasis or obstructive pneumonitis that extends to the hilar region but does not involve the entire lung |
T2a | Tumor >3 cm but ≤5 cm |
T2b | Tumor >5 cm but ≤7 cm |
T3 | Tumor >7 cm or any of the following: |
Directly invades any of the following: chest wall, diaphragm, phrenic nerve, mediastinal pleura, parietal pericardium, main bronchus <2 cm from carina (without involvement of carina) |
Atelectasis or obstructive pneumonitis of the entire lung |
Separate tumor nodules in the same lobe |
T4 | Tumor of any size that invades the mediastinum, heart, great vessels, trachea, recurrent laryngeal nerve, esophagus, vertebral body, carina, or with separate tumor nodules in a different ipsilateral lobe |
Regional lymph nodes (N) |
N0 | No regional lymph node metastases |
N1 | Metastasis in ipsilateral peribronchial and/or ipsilateral hilar lymph nodes and intrapulmonary nodes, including involvement by direct extension |
N2 | Metastasis in ipsilateral mediastinal and/or subcarinal lymph node(s) |
N3 | Metastasis in contralateral mediastinal, contralateral hilar, ipsilateral or contralateral scalene, or supraclavicular lymph node(s) |
Distant metastasis (M) |
M0 | No distant metastasis |
M1 | Distant metastasis |
M1a | Separate tumor nodule(s) in a contralateral lobe; tumor with pleural nodules or malignant pleural or pericardial effusion |
M1b | Distant metastasis (in extrathoracic organs) |
Stage groupings |
Stage IA | T1a-T1b | N0 | M0 |
Stage IB | T2a | N0 | M0 |
Stage IIA | T1a,T1b,T2a | N1 | M0 |
T2b | N0 | M0 |
Stage IIB | T2b | N1 | M0 |
T3 | N0 | M0 |
Stage IIIA | T1a,T1b,T2a,T2b | N2 | M0 |
T3 | N1,N2 | M0 |
T4 | N0,N1 | M0 |
Stage IIIB | T4 | N2 | M0 |
Any T | N3 | M0 |
Stage IV | Any T | Any N | M1a or M1b |