Indeed, ER-neg BC specimens typically exhibit higher levels of TILs when compared to hormone-receptor-positive/HER2-negative BCs (23,48), owing to the generally higher immunogenic background of ER-neg tumors, which contrasts the “cold” immune-suppressive TME often observed in hormone-receptor-positive/HER2-negative BC (21,49,50). The gene discussed is ESR1; the disease is breast cancer.