Figure 2

Performance of SYCN, CA19.9 and the panel of SYCN + REG1B + CA19.9 in early stage (I/II) versus healthy/disease-free. Biomarker performance was assessed in clinically confirmed early-stage (I/II) PDAC samples compared to healthy controls/disease-free individuals in Sample Set A (n = 20 PDAC and n = 92 healthy) (a) and Sample Set B (n = 40 PDAC and n = 47 disease-free) (b). Displayed are the ROC curves for CA19.9 and SYCN, which performed comparably in the two sample sets (p = 0.81 and p = 0.96 showing no significant difference in AUCs of the two curves in Sample Set A and B, respectively). Also displayed is the ROC curve for the panel SYCN + REG1B + CA19.9, which showed the greatest AUC of all two and three marker combinations in both sample sets. Confidence intervals (CI) for AUC were calculated using DeLong’s method. Sensitivity and specificity are given in Additional file 1: Tables S7 and S8.