In silico analysis of the gene expression profiles of 53 primary HER2‐positive specimens from the GHEA cohort (Campiglio et al., 2013) enabled to stratify HER2‐positive BC patients according to the classification of prediction analysis of microarray 50 (PAM50; basal, HER2‐enriched, luminal A, luminal B, and normal‐like molecular subtypes). Here, ERBB2 is linked to breast cancer.