In this study, patients with malignant TEF were often associated with pneumonitis (elevated procalcitonin and C-reactive protein levels, and chest CT showing typical signs of pneumonitis) and malnutrition (decreased hemoglobin and albumin levels), probably leading to a lower survival rate than patients with malignant CAO. This evidence concerns the gene CRP and esophageal atresia/tracheoesophageal fistula.