EGFR and lung adenocarcinoma: This retrospective study included 126 advanced lung adenocarcinoma patients with EGFR/HER2 exon 20 insertion mutations, of which EGFR20ins accounted for 40.5%, and HER2-20ins accounted for 59.5%; the proportion of women and never-smokers was higher, were 59.5% and 79.4%, respectively, which is consistent with the previous report (10, 15).