Table 5 Risk factors for lymph node metastasis and liver metastasis identified by multivariate logistic regression analysis

Age

 <45

1

1

 45–65

0.83

0.692–0.996

0.045

0.751

0.468–1.206

 ≥ 65

0.525

0.438–0.63

< 0.001

0.532

0.332–0.851

Marriage

 Married

1

 Single

0.898

0.826–0.976

0.012

 Unknown

0.806

0.675–0.962

0.017

Race

 Asian or Pacific Islander

1

 American Indian/Alaska Native

0.759

0.469–1.227

0.261

 White

0.732

0.637–0.842

< 0.001

 Black

1.022

0.863–1.21

0.799

Histological grade

 Well differentiated

1

1

 Moderately differentiated

1.644

1.442–1.875

< 0.001

1.501

1.032–2.184

 Poorly differentiated

3.641

3.088–4.292

< 0.001

1.670

1.028–2.714

 Undifferentiated

3.462

2.609–4.593

< 0.001

1.939

0.847–4.437

Histological type

 Adenocarcinoma

1

 Carcinoid tumor

1.752

1.328–2.311

< 0.001

 Neuroendocrine carcinoma

3.74

2.613–5.534

< 0.001

 Mucinous adenocarcinoma

1.046

0.881–1.241

0.607

 Other

1.118

0.933–1.339

0.226

T classification

 T1

1

 T2

2.221

2.03–2.431

< 0.001

Tumor size

 <5 cm

1

1

 ≥ 5 cm

1.125

1.003–1.262

0.045

2.886

2.203–3.783

 Unknown

0.84

0.731–0.967

0.015

2.463

1.8–3.37

CEA

 Negative

1

1

 Borderline

1.468

0.743–2.9

0.269

2.763

0.367–20.815

 Positive

1.385

1.228–1.561

< 0.001

10.436

7.595–14.335

 Unknown

0.74

0.678–0.808

< 0.001

1.395

0.994–1.958

N classification

 N0

1

1

 N1

NA

NA

NA

3.909

2.999–5.095

 N2

NA

NA

NA

12.131

8.670–16.975