Tumor samples from the other three patients exhibited homogeneous HER2 expression by IHC, with two showing strong HER2 protein expression and high ERBB2 amplification ratios (7.44 and 3.31) and one displaying intermediate HER2 protein expression and an ERBB2 amplification ratio by gene‐protein assay of 1.65. Here, ERBB2 is linked to neoplasm.