A previous study [10] reported that the AUC, sensitivity and specificity of DKK1 were 0.830 (0.785–0.875), 70.4% and 84.7% in differentiating AFP-negative HCC from LC, and chronic HBV infected patients, which are superior to the results reported in the present study. The gene discussed is DKK1; the disease is laryngotracheoesophageal cleft.