The mutation was found to be more common in women (47% of Exon 20ins vs. 28% of EGFR wildtype (WT), p = 0.003) [19], Asian patients (15% of Exon 20ins vs. 4% of EGFR WT, p = 0.02) [5], never-smokers (56% of Exon 20ins vs. 20% of EGFR WT, p<0.0001 [5] and 67% of Exon 20ins vs. 26% of other uncommon EGFR mutations, p<0.01) [20], older patients (p = 0.01, p = 0.032 vs. Exon 19 deletion/L858R [11, 19]), and those with adenocarcinoma histology (100% for Exon 20ins vs. 76% of G719X, 82% of L861Q/P, 89% of L858R, and 93% of Exon 19 deletion [p-values not reported]) [22]. This evidence concerns the gene EGFR and adenocarcinoma.