Table 4 Univariate and multivariable Cox analysis for OS of the right-sided EOCCs

Sex

 Female

Ref

 Male

0.857 (0.706–1.041)

0.120

Histology

 Non-specific adenocarcinoma

Ref

 Specific adenocarcinoma

1.339 (1.029–1.743)

0.030^*

0.676 (0.088–5.215)

0.707

 Others

5.119 (0.934–28.039)

0.060

Site

 Cecum

Ref

 Ascending colon

1.096 (0.802–1.498)

0.567

 Hepatic flexure

0.864 (0.628–1.186)

0.364

Pathologic stage

 I-II

Ref

 III-IV

12.989 (9.493–17.772)

 < 0.001^*

7.350 (4.951–10.912)

 < 0.001^*

Surgery of Primary Site

 No

Ref

 Yes

0.029 (0.004–0.219)

0.013^*

0.073 (0.005–1.124)

0.142

Reginal lymph node dissection

 No

Ref

 Yes

0.434 (0.280–0.671)

0.032^*

1.084 (0.295–3.983)

0.903

Radiation

 No

Ref

 Yes

1.985 (1.335–2.952)

0.001^*

1.849 (1.141–2.998)

0.005^*

Chemotherapy

 No/unknown

Ref

 Yes

0.462 (0.368–0.582)

0.004^*

0.516 (0.395–0.674)

0.002^*

Bone metastasis

 No

Ref

 Yes

10.353 (0.876–23.176)

0.053

Liver metastasis

 No

Ref

 Yes

1.508 (1.171–1.943)

0.001^*

4.069 (3.211–5.157)

0.004^*

Lung metastasis

 No

Ref

 Yes

1.633 (1.192–2.238)

0.002^*

2.262 (1.583–3.231)

0.014^*

Grade

 Poor

Ref

 Well and moderate

0.803 (0.733–0.878)

 < 0.001^*

0.508 (0.411–0.627)

0.004^*

Pretreatment CEA

 Negative

Ref

 Elevated

1.402 (1.162–1.693)

 < 0.001^*

1.457 (1.168–1.817)

0.003^*

Perineural invasion

 No

Ref

 Yes

1.736 (1.440–2.094)

 < 0.001^*

1.651 (1.324–2.059)

 < 0.001^*

Tumor size(mm)

  < 54.9

Ref

  > 54.9

1.347 (1.130–1.605)

0.001^*

1.410 (1.079–1.842)

0.012^*