Table 6.

Associations between clinicopathological features and KRAS mutational status

Variable	KRAS wt (n = 284)	KRAS mt (n = 159)	p-value
Age (years)	64.7 ± 12.0	63.3 ± 9.4	0.193
Gender			0.108
Male	153 (53.9)	73 (45.9)
Female	131 (46.1)	86 (54.1)
Smoking status
Never smokers	83 (29.2)	7 (4.4)	< 0.001
Ex-smokers	99 (34.9)	61 (38.4)	0.461
Current smokers	102 (35.9)	91 (57.2)	< 0.001
Clinical stage
I	19 (6.7)	11 (6.9)	0.927
II	24 (8.5)	10 (6.3)	0.412
III	60 (21.1)	38 (23.9)	0.500
IV	181 (63.7)	100 (62.9)	0.860
T stage
T1	39 (13.7)	26 (16.4)	0.455
T1a	7 (2.5)	2 (1.3)	0.499
T1b	16 (5.6)	11 (6.9)	0.588
T1c	16 (5.6)	13 (8.2)	0.299
T2	78 (27.5)	30 (18.9)	0.043
T2a	51 (18.0)	18 (11.3)	0.065
T2b	27 (9.5)	12 (7.5)	0.485
T3	52 (18.3)	37 (23.3)	0.211
T4	115 (40.5)	66 (41.5)	0.835
LN metastasis/−es	212 (74.6)	121 (76.1)	0.734
N stage
N0	72 (25.4)	38 (23.9)	0.734
N1	33 (11.6)	27 (17.0)	0.114
N2	82 (28.9)	48 (30.2)	0.771
N3	97 (34.2)	46 (28.9)	0.259
Extrathoracic metastasis/−es	124 (43.7)	74 (46.5)	0.559
M stage
M0	101 (35.6)	59 (37.1)	0.746
M1a	59 (20.8)	26 (16.4)	0.257
M1b	37 (13.0)	30 (18.9)	0.100
M1c	87 (30.6)	44 (27.7)	0.512
Localization
Right upper lobe	71 (25.0)	44 (27.7)	0.538
Right lower lobe	45 (15.8)	17 (10.7)	0.134
Middle lobe	11 (3.9)	6 (3.8)	0.958
Left upper lobe	52 (18.3)	31 (19.5)	0.759
Left lower lobe	33 (11.6)	34 (21.4)	0.006
Lingula	11 (3.9)	3 (1.9)	0.252
Involvement of two lobes	61 (21.5)	24 (15.1)	0.102
Distribution
Central	64 (22.5)	27 (17.0)	0.165
Peripheral	189 (66.5)	117 (73.6)	0.124
Central and peripheral	31 (10.9)	15 (9.4)	0.624
Size (mm)	45.8 ± 25.8	45.6 ± 25.8	0.937

Data are mean values ± standard deviations for continuous variables and number of patients with percentages in parentheses for categorical variables

Bold numbers indicate significant p-values (< 0.05)