EGFR and diabetes mellitus: Significant differences in the history of smoking, history of alcohol consumption, EGFR mutation status, stages, histological type, body mass index, and underlying diseases including DM (SPLC: 18.75% vs. SPEC: 24.80%; p < 0.001), gout (SPLC: 9.19% vs. SPEC: 12.09%; p = 0.013), and COPD (SPLC: 28.45% vs. SPEC: 35.54%; p < 0.001) were observed between the SPLC and SPEC groups.