Combining prognostic value of serum carbohydrate antigen 19-9 and tumor size reduction ratio in pancreatic ductal adenocarcinoma

Table 2 Cox proportional hazard regression analysis of patients' demographic and clinical characteristics related with overall survival

Variable	Univariate			Multivariate
	HR	95%CI	P value	HR	95%CI	P value
Age in yr, median range	1.043	0.795-1.149	0.857
Sex, male/female	0.948	0.743-1.219	0.395
ASA score classification, 0/1 or 2	1.103	0.854-1.754	0.194
BMI	0.931	0.803-1.140	0.454
TNM stage, I or II/III	1.436	1.217-2.695	0.015	1.526	1.226-4.165	0.007
Neoadjuvant Chx, yes/no	1.201	1.114-2.742	0.024
Neoadjuvant Rtx, yes/no	1.121	0.901-1.537	0.142
Neural invasion, yes/no	1.103	0.965-2.542	0.104
Vascular invasion, yes/no	1.439	1.294-3.594	0.003	1.653	1.253-3.651	0.021
Positive lymph nodes, yes/no	1.729	1.487-4.325	0.001
Tumor resection, R0/R1	0.568	0.321-0.843	0.005
Operation type, Whipple	1.104	0.549-2.130	0.392
CR, ≥ 1/< 1	1.796	1.429-4.104	0.001	1.721	1.373-3.762	0.006
TR, ≥ 1/< 1	1.573	1.282-2.752	0.012	1.435	1.275-4.363	0.014

BMI: Body mass index; Chx: Chemotherapy; CR: Carbohydrate antigen 19-9 ratio; Rtx: Radiotherapy; TR: Tumor size ratio.