Table 6.

Risk factors for underestimation of N-staging

	Univariable analysis			Multivariable analysis
	Odds ratio	95% CI	p value	Odds ratio	95% CI	p value
Age
≥40 years	Reference
<40 years	1.7	1.32~2.19	<0.001	1.5	1.14~1.98	0.004
Gender
Male	Reference
Female	1.37	1.17~1.61	<0.001	1.27	1.07~1.51	0.006
Tumor size
<2 cm	Reference
≥2 cm	4.95	3.70~6.62	<0.001	2.77	2.04~3.77	<0.001
pT-stage
T1	Reference
T2	3.7	2.96~4.63	<0.001	3.11	2.46~3.93	<0.001
T3	3.6	2.93~4.42	<0.001	2.82	2.26~3.51	<0.001
T4	4.14	3.32~5.17	<0.001	3.02	2.37~3.86	<0.001
Tumor location
Distal	Reference
Middle	1.26	1.04~1.51	0.016	1	0.82~1.22	0.981
Upper	1.25	1.02~1.53	0.03	0.84	0.68~1.05	0.118
Diffuse	2.65	1.72~4.09	<0.001	1	0.63~1.59	0.994
Histology
Intestinal	Reference
Diffuse & Mixed	1.87	1.60~2.19	<0.001	1.36	1.14~1.62	<0.001