A recent study has found that increasing ER percentage is associated with a lower likelihood of tumor downstage and pCR at surgery among patients who receive NACT.18 In the era of precision medicine, incorporating quantitative assessments of ER, PR, and Ki-67 expression, the 21-gene RS, or the 70-gene risk scores could help clinicians identify and further classify patient groups with regard to tumor response and neoadjuvant treatment selection as well as subsequent BCS. This evidence concerns the gene MKI67 and neoplasm.