KRAS and lung adenocarcinoma: G12C were the most common subtype in lung adenocarcinoma.[2] Smoking habits are known to affect incidences of the different subtypes, and may contribute to different clinical outcomes.[13,14] In Taiwan, more than half (53%) of lung cancer patients were never smokers, with lung adenocarcinoma being the major histological type.[15] In the present study, we aimed to characterize the clinical and pathological features of patients with KRAS mutation in this non-smoker predominant area.