ESR1 and breast ductal adenocarcinoma: They were mostly Malay (55.8%), had ductal carcinoma (89.4%), were hormone-sensitive (49.4% both ER- and PR-positive), HER2 negative (49.2%), at T2- (40.7%), N1-stage (37.3%), had no metastasis (73.7%), and received early definitive surgery (80.5%) and chemotherapy (62.2%).