TABLE 2.

Univariable analysis of clinicopathological variables in relation to recurrence‐free and overall survival.

Factor	Overall survival			Recurrence‐free survival
	Hazard ratio	95% CI	P value	Hazard ratio	95% CI	P value
Increase of ACA‐positive EVs	3.452	1.155–10.321	0.027	2.735	1.195–2.626	0.017
Preoperative CA19‐9 >100	1.850	0.571–5.997	0.305	1.372	0.484–3.885	0.552
Postoperative CA19‐9 >100	0.769	0.102–5.789	0.799	0.437	0.059–3.232	0.417
Increase in CA19‐9	0.810	0.234–2.800	0.739	1.228	0.459–3.281	0.682
Age	0.584	0.225–1.514	0.269	0.989	0.951–1.029	0.583
Sex (male)	0.964	0.921–1.010	0.125	1.412	0.667–2.988	0.368
Diabetes mellitus (+)	0.687	0.277–1.702	0.417	0.666	0.308–1.439	0.301
Neoadjuvant therapy	1.986	0.832–4.739	0.122	1.809	0.845–3.874	0.127
Operation time >450 min	3.121	0.897–8.917	0.107	1.329	0.491–1.932	0.677
Amount of bleeding >300 g	1.340	0.319–3.971	0.539	1.109	0.490–2.239	0.449
Complication (CD ≧ IIIa) (+)	0.706	0.256–1.945	0.501	1.179	0.514–2.705	0.697
Lymphatic infiltration (0 or 1)	4.466	0.598–33.321	0.144	3.611	0.853–15.282	0.081
Venous infiltration (0 or 1)	22.282	0.006–79,274	0.457	23.121	0.051–10444.77	0.314
Neural infiltration (0 or 1)	1.983	0.264–14.913	0.506	3.028	0.411–22.326	0.277
Serosal invasion (+)	0.769	0.324–1.828	0.553	1.445	0.685–3.046	0.333
Retropancreatic tissue invasion (+)	1.022	0.236–4.428	0.977	1.117	0.345–4.019	0.794
Distal bile duct invasion (+)	2.246	0.849–5.942	0.103	1.114	0.490–2.532	0.797
Duodenal invasion (+)	0.613	0.223–1.690	0.345	0.483	0.195–1.200	0.117
Extrapancreatic nerve plexus invasion (+)	1.468	0.615–3.504	0.387	1.594	0.752–3.376	0.224
Lymph node metastasis	3.717	0.864–15.991	0.078	1.560	0.631–3.860	0.336
Resection margin (R0)	2.171	0.913–5.164	0.079	1.181	0.549–2.539	0.671

Abbreviations: ACA, Amaranthus caudatus agglutinin; CA19‐9, carbohydrate antigen 19‐9; CD, Clavien–Dindo; CI, confidence interval.