Correlation of Mitotic Index (MI) and Tumor Infiltrating Lymphocytes (TILs) to Chemotherapy Response in Triple Negative Breast Cancer (TNBC) at Haji Adam Malik General Hospital Medan

Background: The response to chemotherapy depends on the proliferation of cancer cells. The higher the proliferation of cancer cells, the better the response. Mitotic Index and Tumor Infiltrating Lymphocytes are markers related to the rate of proliferation and cancer immunity. Objectives: to analyze the correlation of Mitotic Index (MI) and Tumor Infiltrating Lymphocytes (TILs) to chemotherapy response in Triple-negative breast cancer (TNBC). Methods: This study used an observational analytic design with a cross-sectional approach. It was conducted at the Division of Oncology Surgical, Department of Surgery, USU Medical Faculty, H. Adam Malik Hospital, Medan, for six months with a sample of 60 people. Results: On average, most respondents are 47 years old, with the youngest age being 27 and the oldest 73 years old. Most respondents have Grade II, with most in stage IIIB. There was no relationship between Tumor Infiltrating Lymphocytes and Chemotherapy Response (p>0.05), with a Positive Predictive Value (NPP) of 47% and a Negative Predictive Value (NPN) of 50%. Conclusion: There is no relationship between the mitotic index and clinical response to chemotherapy, and there is no relationship between tumor-infiltrating lymphocytes and the response to chemotherapy due to influencing factors such as albumin, T stage, menopausal status, and receptor status.