ESR1 and invasive breast carcinoma: Among the invasive breast cancer cases, 9,525 had information on ER status (7,789 ER-positive and 1,736 ER-negative), 7,994 on PR status (5,268 PR-positive and 2,726 PR-negative), and 4,577 on HER2 status (901 HER2-positive and 3,676 HER2-negative).