Univariate regression Multivariate regression OR (95% CI) OR (95% CI) Gender Female 0.868 (0.413, 1.825) 0.708 0.589 (0.231, 1.501) 0.267 Male 1 1 Age ≤57 years old 2.872 (1.330, 6.200) 0.007 3.049 (1.171, 7.941) 0.022 >57 years old 1 1 Tumor size (cm) ≥5 0.963 (0.457, 2.032) 0.922 0.771 (0.305, 1.950) 0.583 <5 1 1 Tumor location Left-sided colon 1.067 (0.495, 2.299) 0.869 1.367 (0.468, 3.994) 0.567 Right-sided colon 1 1 Depth of tumor invasion T4 1.122 (0.455, 2.765) 0.803 1.242 (0.249, 6.193) 0.791 T1 + T2 + T3 1 1 Lymph node metastasis N2 0.877 (0.427, 1.802) 0.722 1.207 (0.474, 3.077) 0.740 N1 1 1 Histopathology grade PD 0.687 (0.250, 1.882) 0.465 1.171 (0.462, 2.967) 0.269 WD + MD 1 1 Lymph-vascular invasion Yes 0.887 (0.413, 1.907 0.759 0.936 (0.355, 2.465) 0.893 No 1 1 Perineural invasion Yes 1.598 (0.774, 3.299) 0.205 0.651 (0.262, 1.619) 0.356 No 1 1 Prseoperative serum CEA level (ng/mL) ≥5 1.970 (0.927, 4.186) 0.078 1.902 (0.688, 5.255) 0.215 <5 1 1 Postoperative serum CEA level (ng/mL) ≥5 2.514 (0.954, 6.627) 0.062 1.267 (0.325, 4.939) 0.733 <5 1 1 Cycles of oxaliplatin-based regimen (cycles) ≤8 5.925 (2.626, 13.371) <0.001 4.995 (1.806, 13.815) 0.002 >8 1 1 Pattern of recurrence/distant metastasis Distal metastasis 1.328 (0.637, 2.771) 0.449 1.029 (0.395, 2.679) 0.953 Local recurrence 1 1
