Table 3.

Cox regression analysis of postoperative variables from two cohorts for overall survival.

	Univariable analysis		Multivariable analysis
Characteristics	HR (95% CI)	P a	HR (95% CI)	P a
Sex (male vs. female)	1.106 (0.673–1.819)	0.691
Age (≥60 vs. <60)	1.224 (0.769–1.950)	0.394
Pathologic T stage
T1	1	<0.001
T2	1.232 (0.517–2.938)	0.638
T3	1.361 (0.624–2.971)	0.438
T4	3.676 (1.639–8.245)	0.002
Pathologic N stage
N0	1	0.001	1	0.002
N1	1.047 (0.487–2.253)	0.906	1.091 (0.502–2.372)	0.826
N2	2.296 (1.377–23.830)	0.001	2.445 (1.401–4.266)	0.002
N3	5.140 (1.759–15.013)	0.003	3.604 (1.118–11.625)	0.032
Group (nonradio vs. radio)	1.382 (0.810–2.359)	0.235	1.674 (0.860–3.258)	0.129
Adjuvant chemotherapy (yes vs. non)	2.391 (0.751–7.610)	0.140
Smoking status (current/former vs. never)	1.254 (0.797–1.972)	0.327
Alcohol use (positive vs. negative)	1.031 (0.650–1.637)	0.896
Pathologic response b (non-MPR vs. MPR)	2.254 (1.237–4.107)	0.008	2.024 (1.101–3.722)	0.023
Nerve invasion (invasion vs. noninvasion)	1.009 (0.519–1.965)	0.978

^a P values from univariable and multivariable Cox regression models.

^b MPR (major pathological response) was defined as less than or equal to 10% residual viable tumor cells.