Table 2.

Univariate analysis of risk factors for recurrence.

Factors		No. of patients	Recurrence-free proportion at 5 years (%)	p-value*)
Gender
	Male	79	76	0.153
	Female	22	85
Age
	<65 years	33	88	0.175
	≥65 years	68	74
ECOG
	0 or 1	80	81	0.365
	2	21	68
BMI (kg/m2)
	<20	29	77	0.618
	≥20	72	82
Smoking history
	Smoker	62	76	0.223
	Non-smoker	39	82
Tumor size
	≤2.0cm	29	93	0.012
	>2.0cm≤3.0cm	31	78
	>3.0cm	41	68
Visceral pleural invasion
	Present	21	61	0.006
	Absent	80	83
Lymphatic permeation
	Present	19	77	0.943
	Absent	82	84
Intratumoral vascular invasion
	Present	33	70	0.027
	Absent	68	83
Histological type
	Squamous cell carcinoma	37	75	0.521
	Adenocarcinoma	55	79
	Other	9	86
Tumor grade
	G1	26	75	0.244
	G2	47	78
	G3	28	88
Pre-operative hypoalbuminemia
	Present	25	59	0.008
	Absent	76	85
Post-operative hypoalbuminemia
	Present	48	62	0.001
	Absent	53	91

^*p<0.05 was defined as indicative of statistical significance.