Clinical characteristics of KRAS mutation subtypes in non-small cell lung cancer population in Xinjiang, China, and their impact on the prognosis of immunotherapy.

Purpose: Non-small cell lung cancer (NSCLC) is a highly fatal malignancy. The Kirsten rat sarcoma viral oncogene (KRAS) gene profoundly impacts patient prognosis. This study aims to explore the correlation between KRAS mutation subtypes, clinical data, and the impact of these subtypes on immunotherapy.

Materials and methods: Tumor samples from 269 NSCLC patients at the Affiliated Cancer Hospital of Xinjiang Medical University were analyzed. Patients received first- or second-line therapy without targeted therapy. Molecular and clinical data were used to analysis KRAS mutation subtypes and treatment outcomes.

Results: KRAS mutations predominantly included G12C, G12D, and G12V subtypes. TP53 had the highest mutation frequency among KRAS mutations, followed by MST1, STK11, and KMT2C. Gender differences were noted among KRAS mutation subtypes, with G12C and G12V mutations prevalent in males, while G12D mutations were less common among males. Smokers exhibited varied KRAS mutation subtypes, with G12C and G12V prevalent in smokers and G12D in nonsmokers. KRAS mutations were mainly in lung adenocarcinoma. TTF-1 and PD-L1 expression differed significantly among KRAS mutations. Patients with G12C and G12V mutations showed higher TMB levels and better immunotherapy outcomes compared to those without KRAS mutations. Conversely, patients with G12D mutations had poorer immunotherapy responses.

Conclusions: KRAS mutation subtypes exhibit distinct clinical and molecular characteristics and varying responses to immunotherapy. G12C and G12V mutations correlate with better immunotherapy outcomes, while G12D mutations are associated with poorer responses.