MKI67 and metastatic malignant neoplasm in the lymph nodes: In the MonarchE trial, which included patients with luminal breast cancer and ≥4axillary lymph node metastases, or 1-3 axillary lymph node metastases, invasion diameter ≥5 cm, histological grade (HG) 3, and Ki67 ≥ 20%, the addition of abemaciclib to postoperative endocrine therapy for 2 years was reported to improve IDFS or distant-relapse-free survival (DRFS) compared to endocrine therapy alone (20), (21), (22).