ESR1 and invasive ductal breast carcinoma: Among the stage M0 patients, 78.9% of them (n=254) had infiltrating ductal carcinoma, 50.6% (n=163) had T3-4 disease, 68.3% (n=220) had poorly/undifferentiated disease, 66.1% (n=213) had HER2-negative disease, 57.8% (n=186) had ER-positive tumors, and 42.5% (n=137) had PR-positive tumors.