ESR1 and breast cancer: The predictors of DSS for patients with stage IIIC breast cancer included ER status, PR status, molecular typing, T stage, LNP number, and LNR (P ≤ 0.001, P ≤ 0.001, P ≤ 0.001, P ≤ 0.001, P=0.002, and P ≤ 0.001, respectively).