Table 2 Cox proportional hazard model based on the uni- and multivariate analyses to determine the independent factors for the overall survival (OS). For the univariate analysis, we selected tubular adenocarcinoma, gastric resection, and postoperative chemotherapy as independent factors affecting the OS. Similarly, for the multivariate analysis, we selected volume reduction and postoperative chemotherapy as independent factors associated with OS

Univariate analysis

Hazard ratio

95 % CI

p value

 Male

0.976

0.518–1.944

0.941

 Age ≥ 68

1.070

0.584–1.954

0.825

 PS ≥ 2

2.329

0.990–4.881

0.053

 ASA-PS ≥ 2

1.156

0.623–2.179

0.648

 Tubular adenocarcinoma

0.483

0.231–0.935

0.030

 P(+) and/or CY (+)

0.886

0.448–1.913

0.744

 LN(+) or H(+)

0.970

0.476–1.851

0.928

 Non-curative gastric resection

0.326

0.172–0.614

<0.01

 Complications (Clavian-Dindo ≥ 2)

1.820

0.832–3.679

0.127

 Postoperative chemotherapy

0.260

0.120–0.626

0.004

Multivariate analysis

Hazard ratio

95 % CI

p value

 Tubular adenocarcinoma

0.531

0.233–1.130

0.102

 Non-curative gastric resection

0.309

0.152–0.615

<0.01

 Postoperative chemotherapy

0.136

0.056–0.353

<0.01