Table 3.

Multivariate logistic regression analysis in the development set.

Characteristics		OR [95% CI]	p
Age (years)	<60	1
	60–74	1.803 [1.165–2.788]	0.008
	≥75	2.978 [1.555–5.703]	0.001
Tumor size (cm)	≥5	1
	<5	3.092 [1.926–4.964]	<0.001
Tumor location	Upper (≥10 cm)	1
	Middle (5–10 cm)	1.771 [1.052–2.982]	0.021
	Lower (<5 cm)	1.704 [1.021–2.844]	0.031
CEA (ng/ml)	≥5	1
	<5	1.858 [1.194–2.892]	0.006