HER2 remained not significantly associated with worse OS when evaluating the HER2 subgroup by including only data on HER2 expression assessed by means of the gold standard (IHC and in case of equivocal HER2 expression (Hoffman scoring system 2+) an additional in situ hybridization method96), or if data on EAC with Barrett’s esophagus (BE) segment was replaced by data on EAC without BE ((HR 1.09 (95%CI 0.46–2.60)) and (HR 1.33 (95%CI 0.78–2.28)), respectively) (Table 1). This evidence concerns the gene ERBB2 and esophageal adenocarcinoma.