ELISA validation for S100A9 was performed in 94 serum samples, including 47 HBV infected LC (39M/8F, age = 46 ± 9) and 47 HBV-HCC (40M/7F, age = 50 ± 11, 22 cases with AFP ≤ 20 ng/mL). Here, AFP is linked to laryngotracheoesophageal cleft.