The predictive value of tumor mutation burden for immune checkpoint inhibitors therapy in non-small cell lung cancer is affected by patients' age.

High tumor mutation burden (TMB), which is associated with increased tumor immunogenicity, has been identified to predict improved response to immune checkpoint inhibitors (ICIs) therapy in non-small cell lung cancer (NSCLC). As host immunity is also significant to eliminate cancer cells, however, its clinical impact on cancer immunotherapy is still largely unknown. Here we explored the influence of age, which is an important characteristic to evaluate immune response of patients, on TMB-based predictive system for ICIs therapy in NSCLC. Our results showed that high TMB was capable of predicting better durable clinical benefit (DCB) in age group, while it was insignificant in age group. Besides, the predictive power of TMB for progression-free survival (PFS) and overall survival (OS) was better in age group than in age group. Our study illustrated that the predictive value of TMB for ICIs therapy was better in young patients than in elderly patients in NSCLC.