ESR1 and breast cancer: Cases with ER-positive or PR-positive malignant neoplasms were more likely to receive HMT therapy within 3 years after diagnosis of breast cancer (8270 [66.9%] and 7070 [57.2%] vs 2444 [37.9%] and 2047 [31.7%] in the non-HMT cohort, respectively) (Table 1).