Table 3 Multivariate analysis of clinicopathologic variables in relation to OS in patients with gallbladder cancer

T stage (T1/T2, T3/T4)

0.635

 N status (N0, N1/N2)

1.770

1.058-2.961

0.030

TNM stage (I-II, III-IV)

0.589

 Differentiation (well or moderately, poorly or undifferentiated)

2.276

1.390-3.727

0.001

 Vascular invasion (positive, negative)

3.184

1.784-5.682

 < 0.001

 Perineural invasion (positive, negative)

3.929

2.325-6.639

 < 0.001

NPS

 0

 1

2.531

1.085-5.904

0.032

 2

3.417

1.419-8.227

0.006