| Tx | Tumor in sputum/bronchial washings but not seen in imaging or bronchoscopy |
| T0 | No evidence of tumor |
| Tis | Carcinoma in situ |
| T1 | ≤3 cm surrounded by lung/visceral pleura, not involving main bronchus |
| T1a(mi) | Minimally invasive carcinoma |
| T1a | ≤1 cm |
| T1b | >1 to ≤2 cm |
| T1c | >2 to ≤3 cm |
| T2 | >3 to ≤5 cm or involvement of main bronchus without carina, regardless of distance from carina or invasion of visceral pleura or atelectasis post-obstructive pneumonitis extending to hilum |
| T2a | >3 to ≤4 cm |
| T2b | >4 to ≤5 cm |
| T3 | >5 to ≤7 cm in greatest dimension or tumor of any size that involves chest wall, pericardium, phrenic nerve or satellite nodules in the same lobe |
| T4 | >7 cm in greatest dimension or any tumor with invasion of mediastinum, diaphragm, heart, great vessels, recurrent laryngeal nerve, carina, trachea, oesophagus, spine or separate tumor in different lobes of ipsilateral lung |
