Table 4 Association between prognostic factors, HBV infection and overall survival in a multivariate analysis

Age (≤ 70 yr/> 70 yr)

1.527 (1.075-2.169)

0.018

The 7th tumor-node-metastasis (TNM) staging (AJCC) (Ia + Ib/IIa + IIb/III/IV)

1.310 (1.129-1.520)

< 0.001

Degree of differentiation (Poorly differentiated or mucinous adenocarcinoma/Moderate differentiated/Well differentiated)

2.134 (1.729-4.538)

0.031

Surgery (No/Yes)

0.553 (0.429-0.713)

< 0.001

Chemotherapy (No/Yes)

0.648 (0.506-0.829)

0.001

Baseline CA199 (Normal/Elevated)

1.602 (1.179-2.176)

0.003

HBV infection

0.038

IC

1 (reference)

CHB

0.414 (0.213-0.807)

0.010

Resolved HBV infection

0.683 (0.450-1.036)

0.073

Non HBV infection

0.630 (0.429-0.925)

0.018