MKI67 and metastatic malignant neoplasm in the lymph nodes: After adjusting for known prognostic factors, including age, comorbidities, lymph node metastasis, adjuvant endocrine therapy, DFI, symptoms, Ki-67 index, distant metastasis location, and systemic treatment modes., patients who received first-line chemotherapy had poorer PFS and OS than patients who received first-line endocrine therapy.