Table 5 Univariate and multivariable Cox analysis for OS of the left-sided EOCCs

Sex

 Female

Ref

 Male

1.264 (0.855–1.868)

0.178

Histology

 Non-specific adenocarcinoma

Ref

 Specific adenocarcinoma

1.623 (0.795–2.087)

0.564

 Others

1.023 (0.587–1.673)

0.351

Site

 Cecum

Ref

 Ascending colon

1.104 (0.758–1.606)

0.607

 Hepatic flexure

1.040 (0.799–1.352)

0.772

Pathologic stage

 I-II

Ref

 III-IV

7.357 (5.762- 9.394)

 < 0.001^*

3.216 (2.332–4.436)

 < 0.001^*

Surgery of Primary Site

 No

Ref

 Yes

0.074 (0.036–0.152)

 < 0.001^*

0.297 (0.104–1.012)

0.203

Reginal lymph node dissection

 No

Ref

 Yes

0.373 (0.262–0.531)

0.021^*

0.531 (0.284–1.193)

0.084

Radiation

 No

Ref

 Yes

1.305 (0.804–2.118)

0.282

Chemotherapy

 No/unknown

Ref

 Yes

0.683 (0.502–0.916)

0.011^*

0.738 (0.553–0.987)

0.040^*

Bone metastasis

 No

Ref

 Yes

2.537 (0.531–12.122)

0.243

Liver metastasis

 No

Ref

 Yes

13.236 (10.702–16.369)

 < 0.001^*

5.763 (4.517–7.352)

 < 0.001^*

Lung metastasis

 No

Ref

 Yes

9.599 (6.118–15.06)

 < 0.001^*

2.295 (1.354–3.890)

0.002^*

Grade

 Well and moderate

Ref

 Poor

2.545 (2.075–3.122)

 < 0.001^*

2.222 (1.736–2.8450)

 < 0.001^*

Pretreatment CEA

 Negative

Ref

 Elevated

4.927 (4.130–5.878)

 < 0.001^*

2.148 (1.741–2.650)

 < 0.001^*

Perineural invasion

 No

Ref

 Yes

3.142 (2.605–3.789)

 < 0.001^*

1.777 (1.415–2.232)

 < 0.001^*

Tumor size (mm)

  < 44.9

Ref

  > 44.9

1.502 (1.275–1.769)

 < 0.001^*

1.067 (0.865–1.315)

0.547