Biomarkers predicting the effect of immunotherapy: what you need to know in practice?

Immune checkpoint inhibitors (ICT) therapy is a successful immunotherapy strategy that is quite effective in a 20–40% of patients with solid tumors. Nevertheless, there is a large group of patients, the proportion of which do not have a clinical response to such therapy and demonstrate adverse event. This explains the importance of personification of immunotherapy and the search for predictive markers. The article is devoted to the review of clinically significant biomarkers of the effectiveness of immunotherapy, such as PD-L1 expression in tumor tissue, microsatellite instability, tumor mutation burden and tumor infiltrating lymphocytes.