MKI67 and neoplasm: Indeed, in the MonarchE trial, patients with ≥4 positive nodes or 1 to 3 positive nodes and either tumour size ≥5 cm, histologic grade 3, or central Ki-67 ≥20% were randomised to receive adjuvant endocrine therapy (ET) with or without a CDK4/6 inhibitor (abemaciclib).