Table 5.

Multivariate Cox regression analyses of clinicopathological features associated with OS of patients with PDAC.

	Developing cohort		Validation cohort
	HR (95% CI)	P	HR (95% CI)	P
TNM stage		<0.001		<0.001
Stage II vs. stage I	2.584 (1.386–4.819)	0.003	2.122 (1.186–3.794)	0.011
Stage III vs. stage I	4.384 (2.285–8.411)	<0.001	4.443 (2.042–6.625)	<0.001
Stroma Low stromal component vs. high stromal component	1.876 (1.227–2.870)	0.004	2.047 (1.322–3.168)	0.001
Grade G3 vs. G1/2	2.124 (1.419–3.179)	<0.001	1.751 (1.158–2.649)	0.008
Perineural invasion With vs. without	2.147 (1.187–3.883)	0.011	2.351 (1.080–5.119)	0.031

CI, confidence interval; HR, hazard ratio; TNM, tumor–node–metastasis. The bold value means significant difference (P < 0.05).