ESR1 and invasive carcinoma: The second patient (case No. 4, Table 3) was a 60-year-old woman with histological grade 3, ER-positive/HER2-negative invasive carcinoma of no special type (IC-NST) involving bilateral breasts and axillary lymph nodes, after bilateral total mastectomy and adjuvant therapy with doxorubicin, cyclophosphamide, paclitaxel, letrozole, and tamoxifen.