EGFR and esophageal squamous cell carcinoma: Despite the failure of some EGFR blockers in ESCC such as EGFR monoclonal antibodies (mAbs) cetuximab and tyrosine kinase inhibitors (TKIs) gefitinib as confirmed by several clinical trials [11–14], subsequent stratified analysis of these trials suggested that patients with squamous histopathological type, EGFR copy number gain (CNG), or overexpression might benefit from EGFR-targeted therapy [15–17], which motivated us greatly to initiate the deeper exploration.