Table 2 Using Cox proportional hazard analyses for postsurgical RFS in development set

Age

− 0.016

0.984(0.963,1.006)

0.157

Male sex

0.063

1.065(0.705,1.608)

0.766

Tumor size(cm)

0.349

1.417(1.222,1.644)

 < 0.001

− 0.248

1.277(1.098,1.495)

0.002

Dominant location

0.165

  Head

− 0.105

0.901(0.566,1.434)

0.659

  Body

− 0.721

0.486(0.227,1.042)

0.486

  Tail

1

1[reference]

–

Tumor density in AP

0.747

  Hyperdense

1

1[reference]

–

  Isodensel

0.301

1.351(0.407,4.491)

0.623

  Hypodense

0.200

1.020(0.373,2.787)

0.969

Tumor density in PVP

 < 0.001

− 0.940

0.598(0.424,0.844)

0.003

  Hyperdense

1

1[reference]

–

  Isodensel

0.407

1.503(0.714,3.163)

0.283

  Hypodense

1.141

3.129(1.526,6.416)

0.002

Tumor necrosis (Yes/No)

0.104

1.110(0.451,2.733)

0.821

Peripancreatic infiltration (Yes/No)

− 1.489

0.226(0.116,0.438)

 < 0.001

1.423

4.151(2.077,8.298)

 < 0.001

Contact to SMV or PV

− 0.228

0.431(0.451,1.405)

0.431

Suspicious metastatic lymph node

− 1.089

0.336(0.223,0.507)

 < 0.001

0.940

2.561(1.653,3.967)

 < 0.001

Cancer antigen 19–9

0.000

1(1,1)

0.009

0.000

1(1,1)

0.430

Bilirubin

0.003

1.003(1.001,1.005)

0.011

Neutrophils/Lymphocytes ratio

0.138

1.148(1.066,1.237)

 < 0.001

0.105

1.111(1.016,1.215)

0.020

Platelets/Lymphocytes ratio

0.000

1(1,1)

0.835

C-reactive protein(mg/L)

− 0.042

0.959(0.905,1.016)

0.159