Lung cancer is a malignant tumor originated from the bronchial mucosa or glands of the lungs, 1,2 which has characteristics of family clustering and genetic susceptibility. 3,4 According to preventive pathology, lung cancer is classified into two categories: small cell carcinoma and non-small-cell carcinoma. 5 Among them, non-smallcell carcinoma includes squamous cell carcinoma, adenocarcinoma, and large cell carcinoma. 6 Lung adenocarcinoma (LUAD) is a type of lung cancer, accounting for 40%-55% in all lung cancer cases.