Table 2. Univariate analysis of potential predictors of ECS.

Clinicopathologic parameters	N−*	pN+ ECS−**	pN+ ECS+***	P-valuea
Gender
Male	45	14	27	0.023b
Female	29	7	5
Age (years)
⩽60	35	10	15	NS
>60	39	11	17
Alcohol habit
(−)	38	8	10	0.005b
(+)	33	13	21
Smoking habit
(−)	39	12	11	NS
(+)	32	9	20
Tumor site
Tongue	45	13	19	NS
Lower gingiva	18	4	5
Floor of mouth	3	2	5
Upper gingiva	2	1	1
Buccal mucosa	6	1	2
Growth pattern
Superficial	18	3	6	NS
Exophytic	28	8	7
Endophytic	28	10	19
Pathological T stage
1–2	65	14	23	0.042c
3–4	9	7	9
Cellular differentiation
Well/moderate	64	19	24	NS
Poor	10	2	8
Mode of invasion
1–3	53	13	14	0.009b
4C–D	21	8	18
Number of positive nodes d
1	—	13	5	0.001e
⩾2	—	8	27
Size of positive nodesf (mm)
Minor axis (3–20)
⩽10	—	13	16	NS
>10	—	8	16
Major axis (5–27)
⩽14	—	14	14	NS
>14	—	7	18
Gene status in primary tumor
CCND1 numerical aberration
(−)	56	16	12	0.0001b
(+)	18	5	20	0.011e
EGFR numerical aberration
(−)	51	18	14	0.018b
(+)	23	3	18	0.004e

Abbreviations: ECS=extracapsular spread; EGFR=epidermal growth factor receptor gene; NS=not significant.

^aThe P-value was determined using the two-tailed Fisher exact test.

^b* vs ^***.

^c* vs ^**.

^dDetermined according to histopathological diagnosis.

^e** vs ^***.

^fDetected by computed tomography.