Table 1.

Baseline characteristics of the included tongue squamous cell carcinoma patients

Items	Cases (n = 141)	Metastases (+)	Metastases (−)	P value*
Gender
Male	75	24	51	0.061
Female	66	12	54
Age (years old)
<  55	59	14	45	0.678
≥ 55	82	22	60
Growth mode of invasive front
Crumb	79	8	71	<  0.001
Trabes	62	28	34
Depth of invasion
<  4 mm	43	1	42	<  0.001
≥ 4 mm	98	35	63
Pathological differentiation
Well	48	7	41	0.032
Moderate/poor	93	29	64
Neurovascular invasion
Yes	18	11	7	<  0.001
No	123	25	98
Location
Anterior	14	1	13	0.053
Middle	103	25	78
Back	24	10	14
T stage
T1	60	8	52	0.004
T2	81	28	53
Smoking
Yes	59	21	38	0.02
No	82	15	67
Drinking
Yes	52	21	31	0.002
No	89	15	74
Treatment
Neck dissection	69	21	48	0.191
Observation	72	15	57

P^*: chi-square test