ESR1 and triple-negative breast carcinoma: The plurarity of patients had triple-negative breast cancer (ER, PR and HER2 negative; n = 30; 46.9%), followed by estrogen receptor (ER)—positive and/or progesterone receptor (PR)—positive, human epidermal growth factor receptor 2 (HER2)—negative (luminal-like) (n = 28; 43.8%), or HER2-positive, ER-negative, PR-negative disease (n = 5; 7.8%) at time of the initial MTB presentation; one patient (1.6%) had triple-positive disease (ER-positive, PR-positive and HER2-positive) (Figure 3).