ESR1 and breast cancer: A meeting abstract describes immunostaining of 10 rabbit adenocarcinomas for ER-α, the basal cytokeratins 5 and 6, as well as HER2 and the subsequent identification of molecular subtypes comparable to those in breast cancer of women, i.e., normal-like, luminal-like A, basal-like and HER2 overexpression [46].