Table 2.

The relationship between I stage and clinicopathological characteristics.

	I stage 0	I stage 1	I stage 2	I stage 3	P value
	(n = 112)	(n = 97)	(n = 66)	(n = 48)
Age (years)					0.817
≤60	66	58	37	25
>60	46	39	29	23
Gender					0.375
Female	18	14	5	5
Male	94	83	61	43
Tumor length (cm)					<0.001
≤3	45	31	9	4
>3	67	66	57	44
Tumor location					0.488
Upper	8	4	1	4
Middle	51	49	28	23
Lower	53	44	37	21
Vessel involvement					0.385
Negative	99	79	54	38
Positive	13	18	12	10
Perineural invasion					0.043
Negative	98	70	52	40
Positive	14	27	14	8
Differentiation					0.310
Good	17	10	12	5
Moderate	80	65	41	30
Poor	15	22	13	13
T stage					<0.001
T1	33	18	3	1
T2	23	14	11	7
T3	50	58	42	29
T4	6	7	10	11
N stage					<0.001
N0	71	55	32	16
N1	30	30	12	15
N2	6	9	12	10
N3	5	3	10	7
TNM stage					<0.001
I	46	21	9	5
II	31	41	22	10
III	35	35	35	33