Table 3 Univariate and multivariate analysis of overall survival in the training cohort

Age

1.01 (1.00-1.02)

0.003

1.01 (1.00-1.02)

0.003

Size

 ≤ 5 cm

Ref.

Ref.

 > 5 cm

1.39 (1.15–1.69)

0.001

1.12 (0.91–1.37)

0.292

Gender

 Male

Ref.

 Female

0.94 (0.78–1.14)

0.538

Subsite

0.729

 Right

Ref.

 Left

0.94 (0.76–1.16)

0.538

 Rectal

0.85 (0.49–1.48)

0.568

Grade

 Well

Ref.

 Poor

1.01 (0.65–1.57)

0.957

T stage

 T1-3

Ref.

Ref.

 T4

1.83 (1.50–2.24)

< 0.001

1.43 (1.16–1.77)

0.001

N stage

 < 4 nodes

Ref.

Ref.

 ≥ 4 nodes

2.15 (1.68–2.76)

< 0.001

2.01 (1.55–2.61)

< 0.001

TNM stage

 III

Ref.

Ref.

 IV

2.22(1.83–2.70)

< 0.001

1.83(1.47–2.27)

< 0.001

PNI

 Absent

Ref.

Ref.

 Present

1.35(1.11–1.63)

0.002

1.04(0.85–1.27)

0.727

TD

 Negative

Ref.

Ref.

 Positive

1.75(1.44–2.12)

< 0.001

1.44(1.16–1.78)

< 0.001

CEA

 Negative

Ref.

Ref.

 Positive

1.61(1.33–1.97)

< 0.001

1.25(1.01–1.55)

0.039

Chemotherapy

 No

Ref.

Ref.

 Yes

0.50(0.40–0.60)

< 0.001

0.46(0.371–0.57)

< 0.001