A recent review concerning HER2-positive IBC showed that three factors are associated with an increased pCR rate: (1) high HER2 combined with low estrogen receptor 1 gene expression levels, (2) a ‘HER2-enriched’ PAM50 intrinsic subtype, and (3) higher levels of tumor infiltrating lymphocytes [36]. The gene discussed is ESR1; the disease is inflammatory breast carcinoma.