ESR1 and breast cancer: BMI, body mass index; HR, hormone receptor; ER, estrogen receptor; PR, progesterone receptor; HER2, human epidermal growth factor receptor 2; BRCA, breast cancer gene; ECE, extracapsular extension; LVI, lymphovascular invasion; AC-T, Doxorubicin + Cyclophosphamide + Paclitaxel; TC, Paclitaxel + Cyclophosphamide; PTCH, Pertuzumab + Paclitaxel + Carboplatin + Trastuzumab; PTH, Paclitaxel + Carboplatin + Trastuzumab.