In contrast, Mu et al. 47found no significant correlation between PD-L1 expression and EGFR/KRAS/BRAF/ALK expression in stage I NSCLC patients, similar to Zhang et al. 54, who found no significant relationship between PD-L1 expression and EGFR/KRAS expression in lung adenocarcinoma. Here, KRAS is linked to lung adenocarcinoma.