The two groups had similar basic features, including age (P=0.213), sides (P=0.244), menstruation status (P=0.363), tumour size (P=0.555), histological grade (P=0.261), lymph node status (P=0.914), clinical stage (P=0.057), ER status (P=0.689), PR status (P=0.986), PR status (P=0.635), Ki-67 level (P=0.292), and targeted therapy (P=0.165). This evidence concerns the gene ESR1 and neoplasm.