In our study, we used the HER2 scoring criteria for breast cancer because morphologically, the tumor arrangement of ESCC is closer to that of breast cancer, and ESCC tumor cells lack basolateral or lateral membranous reactivity which has been emphasized in the HER2 testing guidelines for gastroesophageal adenocarcinoma [18]. The gene discussed is ERBB2; the disease is esophageal squamous cell carcinoma.