Among rare EGFR mutations in NSCLC, G719X substitutions (which include G719S, G719A, G719C and G719D substitutions) are one of the more commonly observed mutations second only to exon 20 insertions and represent approximately 1.5–3% of all EGFR mutations in NSCLC [8]. This evidence concerns the gene EGFR and non-small cell lung carcinoma.