Reis-Filho et al. showed a basal-like immunophenotype (ER-, HER2-, EGFR + and/or CK5/6 +) in 59 out of 65 cases of metaplastic breast cancer that produces stromal matrix that is an epithelial carcinoma with areas of mesenchymal differentiation [17]. Here, ERBB2 is linked to breast carcinoma.