CTLA4 and non-small cell lung carcinoma: Conversely, no significant benefit was observed in patients aged≥65, low TMB (TMB<10 or TMB<20), non-smokers, without brain metastases, or when the control group received monotherapy immunotherapy (all p>0.05 and P_interaction <0.05).<h4>Conclusion</h4>Dual ICI therapy with PD-1/PD-L1 plus CTLA-4 inhibitors improves prognosis in advanced/metastatic NSCLC, with efficacy difference across subgroups.