For example, the genotyping of 3026 lung adenocarcinoma samples revealed a higher frequency of EGFR mutations in never smokers (42.5%) and former smokers (13.5%) compared to current smokers (4.9%); the most common EGFR mutations in this study included exon 19 deletions and L858R point mutations (Figure 2A,B) [37]. Here, EGFR is linked to lung adenocarcinoma.