Table 3. Comparison of clinicopathologic parameters between ALK-positive and ALK-negative lung adenoarcinomas.

Variable	Group	ALK-positive	ALK-negative	P value
Age(years)	≤60	16	208	0.003
	>60	4	245
Gender	Male	14	300	0.727
	Female	6	153
Smoking history	Never or light smoker	7	173	0.774
	Smoker	13	280
Histological type	Adenocarcinoma	19	322	0.02
	Others	1	131
Stage	I	5	161	0.024
	II–III	6	203
	IV	9	89
Total		20	453