The P4 panel had significantly improved the performance in diagnosing HCC patients than AFP, PIVKA-II and their combination, with the highest AUC, sensitivity and specificity (Validation Set: HCC/LC: AUC: 0.979, sensitivity: 0.925, specificity: 0.915; HCC/HC: AUC: 0.992, sensitivity: 0.975, specificity: 1.000) (Fig. 6a, Supplementary Fig. 5a, b). Here, AFP is linked to hepatocellular carcinoma.