In terms of the risk group of HCC (CHB), miR-21 also had a better performance than AFP (AUC 0.789, 95% CI 0.739–0.839, sensitivity 76.9%, specificity 85.7% versus AUC 0.634, 95% CI 0.571–0.697, sensitivity 59.3%, specificity 69.7%, Figure 4C). This evidence concerns the gene AFP and hepatocellular carcinoma.