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

Figure 4 Prognostic values for both carbohydrate antigen 19-9 ratio and tumor size ratio. A-D: Interaction between carbohydrate antigen 19-9 ratio (CR) and tumor size ratio (TR; A) and area under the receiver operating characteristic curves performed to compare the predictive overall survival values of the variable of CR (B), TR (C) and the combined predictive value of CR and TR (D).