Table 2. Univariate analysis of clinicopathological parameters with overall survival.

Clinicopathological parameters	Log-Rank test			Cox analysis
	Median survival time (95% CI)	P		HR (95% CI)	P
Age
≤60 years	19.0 (15.3–22.7)	0.083		1.55 (0.93–2.58)	0.096
>60 years	13.0 (11.5–14.5)
Gender
Male	16.0 (10.6–21.4)	0.827		1.06 (0.63–1.79)	0.833
Female	14.0 (9.9–18.1)
Cancer location
Head	13.0 (9.5–16.6)	0.828		0.94 (0.55–1.63)	0.833
Body tail	18.0 (12.3–23.8)
Differentiation
High	20.0 (14.6–25.5)	0.196		1.38 (0.83–2.31)	0.213
Poor	13.0 (11.7–14.3)
Size
≤2 cm	20.0 (14.2–25.6)	0.350		1.44 (0.65–3.17)	0.368
>2 cm	14.0 (11.1–16.9)
Lymph node
Negative	16.0 (11.4–20.1)	0.411		1.26 (0.72–2.20)	0.428
Positive	12.0 (9.7–14.3)
Staging
I, II	14.0 (10.4–17.4)	0.185		0.63 (0.31–1.28)	0.203a
III, IV	19.0 (11.1–26.9)
Neurovascular invasion
No	17.0 (12.4–21.6)	0.382		0.80 (0.48–1.34)	0.398
Yes	14.0 (4.86–23.1)

^a, the group with later staging had a longer postoperative overall survival.