CDK4 and breast cancer: Given that trial designs for monarchE, PALLAS, and PENELOPE-B pre-dated the era of transcriptome testing for risk stratification, the clinical utility of transcriptomic risk recurrence tools has not been clearly established with CDK4/6 inhibitors in early breast cancer with intermediate or high risk of recurrence; as such, focus directed toward ongoing trials of CDK4/6 inhibitors may shed light on the matter70–72.