ESR1 and breast cancer: AR: Androgen receptor; BC: Breast cancer; EGFR: Epidermal growth factor receptor; ER-: Estrogen receptor negative; ER+: Estrogen receptor positive; FOXA1: Forkhead box protein A1; GATA3: GATA binding protein 3; GCDFP15: Gross cystic disease fluid protein 15; IHC: Immunohistochemical; TNBC: Triple-negative breast cancer; TRPS1: Trichorhinophalangeal syndrome type 1; WT1: Wilms' tumor 1.