The procalcitonin levels [0.19 (0.05, 1.70) vs. 0.05 (0.05, 0.10) μg/L, P = 0.001] and C-reactive protein levels [57.90 (33.10, 82.95) vs. 27.09 (12.20, 52.65) mg/L, P = 0.003] were significantly higher in the malignant TEF group than in the malignant CAO group. The gene discussed is CRP; the disease is esophageal atresia/tracheoesophageal fistula.