Table 6

Recurrence-free proportion of patients stratified by T classification and IVI status in the entire cohort

T classification	Patients (%)	Recurrence-free proportion at 5 years (%)	Group	IVI status	Patients (%)	Recurrence-free proportion at 5 years (%)	Univariate p value by log rank test
T1a	515 (23)	90	A	(−)	425 (19)	93.1	<0.001^*^†
T1a	515 (23)	90	B	(+)	90 (4)	69.3	<0.001^*^†
T1b	448 (20)	81.1	C	(−)	312 (14)	89.7	<0.001^*^†
T1b	448 (20)	81.1	D	(+)	136 (6)	62.7	<0.001^*^†
T2a	825 (36)	62.4	E	(−)	302 (13)	78.4	<0.001^*^†
T2a	825 (36)	62.4	F	(+)	523 (23)	53	<0.001^*^†
T2b	158 (21)	52.1	G	(−)	37 (16)	70.5	0.021^*^†
T2b	158 (21)	52.1	H	(+)	121 (5)	46.4	0.021^*^†
T3	336 (14)	41.2	I	(−)	75 (3)	53.1	0.031^*^†
T3	336 (14)	41.2	J	(+)	261 (11)	37.4	0.031^*^†
T4	13 (6)	34.2	K		13 (6)	34.2	0.215^‡
Total	2295	68.6

T classification based on the 7th edition of the TNM Classification for Lung and Pleural Tumours.
↵* Indicates significance.
↵† p value for each T subclassification with or without IVI.
↵‡ p value vs group J.
IVI, intratumoral vascular invasion.