A First Reported Combination of Exon 18 Missense (G719X) Mutation and Exon 20 Insertion Mutation (Exon20ins) Of Epithelial Growth Factor Receptor in A Patient with Non-Small Cell Lung Carcinoma

The majority of non-small cell lung cancer (NSCLC) associated with epidermal growth factor receptor (EGFR) mutations involve exon 19 deletion mutations and exon 21-point mutation L858R (arginine for leucine substitution at amino acid 858). G719X point mutation (substitutions of the glycine at position 719 to other residues) in exon 18 and insertion in exon 20 are less commonly detected. However, the combination of the latter two mutations has never been reported. We report the first case of metastatic NSCLC with EGFR mutation harboring both exon 18 missense point mutation (G719X) and exon 20 insertion (exon20Ins).