In this study, we retrospectively explored the impact of single-gene mutations in KRAS, STK11, KEAP1, or TP53, as well as STK11, KEAP1, or TP53 mutations according to the KRAS status, on the clinical outcomes of patients with lung adenocarcinoma who received ICIs according to data from the C-CAT database. Here, KRAS is linked to lung adenocarcinoma.