Triple-negative breast cancer (TNBC), which is defined by the lack of expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), accounts for approximately 15%–20% of all breast cancers and has a dismal prognosis with higher risk of recurrence and poor survival outcomes (1). Here, ESR1 is linked to triple-negative breast carcinoma.