Abstract: In recent years, with the gradual in-depth research on immune checkpoints, breakthroughs have been made in the research of immune checkpoint inhibitors (ICI), which has revolutionized the diagnosis and treatment of lung cancer. However, there are still many problems and challenges in the clinical application, such as the limited benefit population, the lack of effective biomarkers, treatment resistance, and the lack of precise combination treatment programs. This article summarized the value and limitations of programmed death ligand-1 (PD-L1) and tumor mutation burden (TMB) as common biomarkers of ICI, as well as other potential new biomarkers, the monitoring and responses to immunological resistance, how to achieve precise immunotherapy and the development results of new drugs.

Key words: Lung neoplasms, Immune checkpoint inhibitors, Biomarkers, Resistance, Combined treatment