Combination of preoperative fibrinogen and D-dimer as a prognostic indicator in pancreatic ductal adenocarcinoma patients undergoing R0 resection

Figure 1 Flowchart of patient selection.

Figure 2 Receiver operating characteristic curve for overall survival analysis according to the preoperative fibrinogen concentration and preoperative D-dimer concentration. A: The area under the receiver operating characteristic (ROC) curve (AUC) was calculated to show the diagnostic ability of preoperative fibrinogen. In this model, the optimal cutoff value of the preoperative fibrinogen concentration was 3.31 g/L, and the AUC was 0.714 (95%CI: 0.649-0.779), while the sensitivity and specificity at the maximal Youden's index were 61.14% and 79.37%, respectively; B: The optimal cutoff value of the preoperative D-dimer concentration was 0.52 mg/L, and the AUC was 0.753 (95%CI: 0.687-0.819), while the sensitivity and specificity at the maximal Youden's index were 58.78% and 78.82%, respectively.

Figure 3 Kaplan-Meier curves were generated based on the optimal cutoff values of the preoperative fibrinogen concentration and preoperative D-dimer concentration. A: Comparison between the preoperative fibrinogen low-concentration group (red line: ≤ 3.31 g/L) and the preoperative fibrinogen high-concentration group (blue line: > 3.31 g/L) (P < 0.05); B: Comparison between the preoperative D-dimer low-concentration group (red line: ≤ 0.53 mg/L) and the preoperative D-dimer high-concentration group (blue line: > 0.53 mg/L) (P < 0.05).

Figure 4 Difference in survival between groups based on preoperative fibrinogen combined with D-dimer indicated by Kaplan-Meier curves. A: Preliminary analysis after subdividing the four groups of enrolled patients (blue line: preoperative fibrinogen concentration > 3.31 g/L and preoperative D-dimer concentration > 0.53 mg/L; green line: preoperative D-dimer concentration > 0.53 mg/L and preoperative fibrinogen concentration ≤ 3.31 g/L; purple line: preoperative fibrinogen concentration > 3.31 g/L and preoperative D-dimer concentration ≤ 0.53 mg/L; and red line: preoperative fibrinogen concentration ≤ 3.31 g/L and preoperative D-dimer concentration ≤ 0.53 mg/L); B: Subgroup analysis of enrolled patients (blue line: preoperative fibrinogen concentration > 3.31 g/L and/or preoperative D-dimer concentration > 0.53 mg/L; and red line: preoperative fibrinogen concentration ≤ 3.31 g/L and preoperative D-dimer concentration ≤ 0.53 mg/L). FIB: Fibrinogen; DD: D-dimer.