Furthermore, Farmer et al. [17] proposed a new classification of breast cancer subtypes based on ERα and AR status: luminal disease positive for both receptors (ERα+/AR+), basal disease negative for both receptors (ERα−/AR−) and molecular apocrine disease with ERα negative and AR positive staining, showing similar characteristics to those of the normal apocrine glands. Here, ESR1 is linked to breast carcinoma.