Table 1.

Definition of T category in 7-TNM and 8-TNM

	7-TNM	8-TNM
T1	Surrounded by visceral PL and not in MB	Surrounded by visceral PL and not in MB
T1mi	-	Minimal invasive adenocarcinoma
T1a	Size ≤2 cm	Size ≤1 cm
T1b	2 cm < size ≤3 cm	1 cm < size ≤2 cm
T1c	-	2 cm < size ≤3 cm
T2	MB (≥ 2 cm distal to carina), visceral PL, partial LA or OP	MB (regardless of distance from carina), visceral PL, part or all LA or OP
T2a	3 cm < size ≤5 cm	3 cm < size ≤4 cm
T2b	5 cm < size ≤7 cm	4 cm < size ≤5 cm
T3	Size >7 cm Parietal PL, chest wall, diaphragm, phrenic N, mediastinal PL, parietal pericardium, MB (< 2 cm distal to carina), entire LA or OP, separate nodule in same lobe	5 cm < size ≤7 cm Separate nodule in same lobe, parietal PL, chest wall, phrenic N, mediastinal PL, parietal pericardium
T4	Mediastinum, heart, great vessels, trachea, recurrent laryngeal N, esophagus, vertebral body, carina, separate nodule in a different ipsilateral lobe	Size >7 cm Separate nodule in a different ipsilateral lobe, diaphragm, mediastinum, heart, great vessels, trachea, recurrent laryngeal N, esophagus, vertebral body, carina

7-TNM seventh American Joint Committee on Cancer TNM staging system, 8-TNM eighth American Joint Committee on Cancer TNM staging system, PL pleura, MB main bronchus, LA lung atelectasis, OP obstructive pneumonitis, N nerve