Table 1.

Univariate and multivariate Cox proportional hazard survival analyses of overall survival

Factor	Hazard ratio	195% CI of HR	P value
Univariate
Age Increasing by 1	0.99	[0.97, 1.01]	0.42
Gender female vs male	0.83	[0.55, 1.27]	0.4
Adjuvant chemotherapy yes vs no	0.48	[0.28, 0.81]	0.0065
H-score > 100 vs < 100	0.68	[0.45, 1.05]	0.078
Grade 3 vs (1 and 2)	1.5	[0.97, 2.30]	0.067
N stage 1 vs 0	2.53	[1.39, 4.57]	0.0022
T stage (3 and 4) vs (1 and 2)	5.12	[1.61, 16.33]	0.0058
LVSI positive vs negative	0.65	[0.42, 1.03]	0.065
PNI positive vs negative	0.75	[0.45, 1.25]	0.28
Surgical margin status positive vs negative	1.87	[1.21, 2.88]	0.0047
Multivariate *
Adjuvant chemotherapy yes vs no	0.45	[0.26, 0.78]	0.0042
ENT1 H-score > 100 vs < 100	0.7	[0.45, 1.03]	0.09
N stage 1 vs 0	2.33	[1.27, 4.25]	0.006

^*the overall p value of the final multivariate model was less than 0.001 (log-rank test)

Univariate and multivariate survival analyses were conducted to evaluate the potential associations between H-score, adjuvant chemotherapy treatment, tumor grade, N stage, T stage, lymphovascular space invasion (LVSI), perineural invasion (PNI), surgical margin status, and median overall survival. The multivariate analyses were performed using a stepwise backward approach. Due to the relatively small sample size, the final multivariate model included variables with p value < 0.10.