Table 5.

Multivariate Cox regression analysis of factors associated with recurrence-free survival.

Variables	HR	95% CI	p-Value
Body mass index	1.08	1.01–1.16	0.021
Moderate and poor tumor grading	2.49	1.2–5.2	0.014
Positive perineural Invasion	2.92	1.02–8.3	0.045
Positive lymph nodes	2.01	1.11–3.65	0.021
Resection margin positive	1.89	1.02–3.4	0.019