Table 4 Multivariate analysis of the metastatic lymph node ratios and the other clinico-pathological characteristics

Sex (male vs. female)

0.731

0.469–1.138

0.166

Age (years old)

1.026

1.006–1.045

0.009

Tumor number

1.299

0.706–2.391

0.401

Location of tumor

Middle/Upper

2.612

0.601–11.361

0.200

Lower/Upper

1.605

0.362–7.117

0.534

Maximum tumor diameter (cm)

2–4/≤ 2

3.841

1.317–11.208

0.014

> 4/≤ 2

4.546

1.572–13.143

0.005

pT category

pT2/pT1

1.025

0.376–2.795

0.961

pT3/pT1

2.687

0.979–7.325

0.055

pT4/pT1

1.157

0.192–6.982

0.874

Histological type

G2/G1

2.163

1.086–4.308

0.028

G3/G1

2.313

1.285–4.136

0.005

Histological growth pattern (expanding vs. infiltrative)

0.923

0.579–1.470

0.736

lymphatic vessel infiltrate (present vs. absent)

0.814

0.504–1.316

0.401

pN category

PN1/pN0

1.980

1.043–3.758

0.037

pN2/pN0

2.987

1.138–7.841

0.026

pN3/pN0

4.380

1.201–15.966

0.025

Metastatic lymph nodes ratio (%)

1–39/0

1.980

1.043–3.0785

0.037

40–79/0

4.726

1.502–14.872

0.008

80–100/0

11.841

2.787–50.321

0.001