B. Multivariate logistical regression analysis determined the risk factors associated with mortality in DM and non-DM subjects.

	DM			Non-DM
	OR	95% C.I.	P-value	OR	95% C.I.	P-value
N status
N = 0	1.00			1.00
N > 0	4.19	1.67–10.53	0.002	1.76	1.02–3.04	0.042
Tumor size
T1–T3	1.00			1.00
T4	2.22	0.81–6.1	0.12	3.40	1.79–6.45	p < 0.001
Stage
I–II	1.00			1.00
III–IV	1.10	0.2–5.98	0.911	1.60	0.61–4.17	0.337
Lymphovascular permeation
Positive	1.74	0.62–4.93	0.295	1.36	0.72–2.58	0.339
Negative	1.00			1.00
Cell differentation
Well	1.00			1.00
Moderate	1.22	0.5–2.97	0.666	1.96	1.18–3.26	0.009
Poor	2.94	0.48–18.03	0.243	2.39	0.97–5.88	0.057
Perineural invasion
Negative	1.00			1.00
Positive	0.82	0.3–2.2	0.69	1.53	0.89–2.62	0.123