EGFR and adenocarcinoma: Our subgroup meta-analyses demonstrated that the benefit of adjuvant EGFR-TKIs over control group with respect to DFS were evident in most subgroups, including smoker (HR 0.42, 95% CI 0.23–0.77), non-smoker (HR 0.47, 95% CI 0.29–0.75), EGFR exon 19 deletion (HR 0.42, 95% CI 0.23–0.77), EGFR exon 21 L858R (HR 0.56, 95% CI 0.37–0.84), adenocarcinoma (HR 0.49, 95% CI 0.36–0.69), male (HR 0.43, 95% CI 0.22–0.85), female (HR 0.38, 95% CI 0.22–0.66), age < 65 (HR 0.44, 95% CI 0.34–0.56), age ≥ 65 (HR 0.41, 95% CI 0.30–0.56), ECOG was 0 (HR 0.33, 95% CI 0.18–0.60) and 1 (HR 0.38, 95% CI 0.24–0.59).