Two studies, which jointly included 420 patients with stage I Non-Small-Cell Lung Carcinoma (NSCLC), suggested that high EPHA2 expression was correlated with well-differentiated tumors, reduced smoking status, adenocarcinoma histological type, stage IA tumors, as well as the presence of Epidermal Growth Factor Receptor (EGFR) gene mutations. This evidence concerns the gene EGFR and adenocarcinoma.