KRAS and adenocarcinoma: In the case of lung cancer, the KRAS mutation is associated with the histology of cancer (adenocarcinoma versus squamous cell carcinoma: 37.2% versus 4.4%), smoking history of the patients (smokers versus non-smokers: 30% versus 11%), gender (female versus males: 31.35% versus 23.7%), and the ethnicity (Caucasian versus Asian: 26% versus 11%) [155,156].