The primary outcome was to evaluate the association of each of the specific clinical and CT patterns (absence of smoking status, female sex, early disease stage, GGO, air bronchogram, pleural retraction, spiculation, and vascular convergence) to EGFR mutation in exon 21 as compared to EGFR mutation exon 19 among patients with lung adenocarcinoma. Here, EGFR is linked to lung adenocarcinoma.