Liquid biopsy as a source of potential biomarkers for checkpoint inhibitor treatment in non-small cell lung cancer

Abstract

Lung cancer (LC) is the leading cause of cancer-related mortality around the world. Immune checkpoint inhibitors (ICIs) have revolutionized the treatment and improved clinical outcomes of non-smallcell lung cancer (NSCLC) patients. However, while some patients have good response to ICI others are refractory to therapy or have life threatening adverse reactions. There are still no good strategies to identify responders to ICIs. That is why personalization of ICI therapy based on a patient's unique genomic profile represents an attractive strategy to improve NSCLC treatment. There are continuous efforts to find predictive biomarkers to identify patients who are likely to respond to ICIs. In turn, these strategies are required to spare patients the time, expenses, and toxicity while trying out therapies from which they will not derive any benefit. Based on this, non-invasive liquid biopsy has the potential to help identify the patients who may respond to ICI. Liquid biopsy derived circulatory tumor DNA, circulatory tumor cells, and immune cell-based biomarkers could be new biomarkers that will guide clinical decisions for checkpoint inhibitor treatment in NSCLC. Furthermore, these biomarkers can serve for monitoring the treatment response and unraveling the mechanisms of resistance.