The HCC index showed an area under the receiver operating characteristic curve (AUROC) of 0.98 (95% confidence interval 0.92–1.00), a sensitivity of 87% and specificity of 100% for the diagnosis of HCC at a cutoff value of 0.61[41], proving superior to cfDNA alone or AFP alone in the diagnosis of HCC[41]. The gene discussed is AFP; the disease is hepatocellular carcinoma.