Predictors of the formation of antitumor immunity in breast cancer patients and the analysis of the results of the use of immune checkpoint inhibitors

Breast cancer (BC) is one of the most common forms of malignant neoplasms among women and is the leading cause of cancer-related mortality. This complex and heterogeneous disease is formed depending on the presence of overexpression of various receptors on the surface of tumor cells. Despite significant advances in the therapy of early and metastatic BC, many patients continue to demonstrate disease progression against the background of traditional treatment methods, which indicates immunosuppression or a defect in the immune system.The aim of this work is to review the scientific literature on the main mechanisms of antitumor immunity in patients with BC and the prospects for the use of immunotherapy.Previously, BC was not considered a particularly immunogenic tumor, but new data show that different tumor subtypes can exhibit immunogenicity, which opens up new prospects for the use of immune checkpoint inhibitors. Features of the tumor immune microenvironment and the presence of tumor infiltrating lymphocytes are becoming important markers that help predict responses to immunotherapy. The effectiveness of such approaches is demonstrated by clinical studies, where the use of immune checkpoint inhibitors in combination with chemotherapy has shown an improvement in the response to therapy. Such studies confirm that even in cases where there is a residual tumor after neoadjuvant treatment, the use of immunotherapy can increase survival. From the presented analysis of literature sources, it follows that BC carcinogenesis is accompanied by suppression of the antitumor activity of the immune system. Quantitative analysis of various predictors allows us to determine the effectiveness of immune drugs. Thus, given the diversity of BC subtypes and many factors affecting the effectiveness of treatment, it becomes obvious that careful patient selection and a personalized approach to immunotherapy are necessary to achieve optimal results. In the future, research in the field of biomarkers should be continued to better predict the response to immunotherapy and minimize adverse effects.