The results showed that patients with specific characteristics (female, non-smoking, PS of 0–1, adenocarcinoma, recurrent disease, EGFR mutations, receiving EGFR-TKI therapy) had a significantly longer survival than patients with opposing characteristics (male, smoker, PS ≥ 2, squamous cell carcinoma, locally advanced and metastatic disease, wild-type EGFR, not receiving EGFR-TKI therapy) (Table 2). This evidence concerns the gene EGFR and squamous cell carcinoma.