Potential biomarkers and resistance mechanisms of atezolizumab in a patient with lung squamous cell carcinoma.

Lay abstract The authors aimed to figure out potential biomarkers and mechanisms associated with immune checkpoint inhibitor resistance by monitoring changes during treatment in a lung squamous cell cancer patient. Interestingly, EGFR exon 20 insertion, decreased PTEN copy number and NOTCH1 mutation as well as changes in CD8⁺ T cells and macrophages were observed after disease progression. Thus, the authors suggest that these changes may be associated with atezolizumab resistance.