Table 1. Characterization of lung adenocarcinomas (n=465) classified by the IASLC/ATS/ERS system.

Clinical information	Pathological subtypes
	Total 465 100.0%	PPA 226 48.6%	APA 128 27.5%	IMA 41 8.8%	SPA 38 8.2%	LPA 22 4.7%	MPA 10 2.2%	P-value
Sex
Female	230	121	59	22	12	13	3	0.088
Male	235	105	69	19	26	9	7
P (compared to Total)		0.331	0.5494	0.6286	0.0421	0.3934	0.3394
Age
<50	84	37	22	10	10	3	2	0.818
50–59	160	81	45	13	13	5	3
≥60	221	108	61	18	15	14	5
P (compared to Total)		0.8435	0.9706	0.6075	0.4136	0.3318	0.9568
Smoking history								0.0013
Nonsmoker	312	163	79	31	16	18	5
Smoker	153	63	49	10	22	4	5
P (compared to Total)		0.1904	0.2922	0.2995	0.0025	0.1691	0.3119
Differentiation
High	178	100	42	16	1	18	1	< 0.0001
Intermediate	164	88	47	16	5	3	5
Poor	123	38	39	9	32	1	4
P (compared to Total)		0.0186	0.4817	0.7996	< 0.0001	0.0002	0.1876
Stage
I	211	107	58	18	11	14	3	0.4801
II	67	33	14	8	8	2	2
IIIA	136	62	41	12	12	6	3
IIIB/IV	51	24	15	3	7	0	2
P (compared to Total)		0.9555	0.7537	0.7648	0.1758	0.2236	0.6957

LPA: lepidic predominant adenocarcinoma; APA: acinar predominant adenocarcinoma; PPA: papillary predominant adenocarcinoma; MPA: micropapillary predominant adenocarcinoma; SPA: solid predominant adenocarcinoma; IMA: invasive mucinous adenocarcinoma. P-values were determined by Chi-square test; red font denotes statistically significant values.