We confirmed the performance in evaluating CNV using NGS, achieving a concordance of 92% between NGS and IHC for evaluating HER2 CN in GA tumor samples, which were consistent with previous studies (Cenaj et al. 2019; Pfarr et al. 2017; Ross et al. 2017; Su et al. 2017; Yeh et al. 2019). The gene discussed is ERBB2; the disease is neoplasm.