ESR1 and breast carcinoma: Gallen International Breast Cancer Conference, namely, luminal A (ER/PR positive, HER2 negative, KI67 < 20%, the percentage indicates the results of immunohistochemical staining of patient samples), luminal B is divided into HER2 negative (ER/PR positive, ER/PR positive, HER2 overexpression), Erb-B2 overexpression (HER2 overexpression, ER/PR absent), basal-like TNBC (ER/PR absent, HER2 negative) and other specific subtypes [13].