Table 1 Differences of the parameters among UI low or high subgroups

Age (y)

0.463

 < 60

157

72

85

 ≥ 60

116

59

57

Sex

0.070

 Male

136

73

63

 Female

137

58

79

Type of resection

0.001*

 Lobectomy

208

112

96

 Segmentectomy

65

19

46

Pathology

0.181

 ADC

252

117

135

 SCC

14

10

4

 Others

7

4

3

Smoking status

0.143

 Never

195

88

107

 Current + former

78

43

35

Alcohol status

0.608

 Never

182

85

97

 Current + former

91

46

45

Comorbidity

0.580

 With

69

31

38

 Without

204

100

104

T stages

0.686

 T₁ + T₂

267

129

138

 T₃ + T₄

6

2

4

N stages

 < 0.001*

 N₀

241

106

135

 N₁ + N₂

32

25

7

TNM stages

0.004*

 I

237

105

132

 II

22

17

5

 III

14

9

5