Targeted next generation sequencing (NGS) enables identification of rare EGFR exon-20 insertion (p.H773_V774insPHPH) in lung adenocarcinoma patient

The present case report describes the incidence of a rare EGFR exon-20 insertions (p.H773_V774insPHPH) in a lung adenocarcinoma patient (44/Male) using targeted next generation sequencing. Exon-20 insertions are known as challenging subset of non-small cell lung cancer (NSCLC) mutations resistant to traditional EGFR tyrosine kinase inhibitor (TKI). There are only two cases of present exon-20 insertion variant reported, which includes one patient (1/1127) from MSKCC study and another case report from Wang et al., Frontiers in oncology,2022. We further validated our findings using Sanger sequencing to confirm variant identified by NGS. Patient was advised gefitinib + chemotherapy. Our findings emphasize the complexity of EGFR exon-20 insertions and advocates for personalized therapeutic strategies in NSCLC management.