Detection of Rare Targetable EGFR Variant in Metastatic Non-small Cell Lung Carcinoma by Next Generation Sequencing: A Case Report

ABSTRACT Single gene assays for variants in Epidermal Growth Factor Receptor (EGFR) demonstrate actionable and sensitising mutations in majority of the cases. However, the emergence of next generation sequencing platforms has facilitated the detection of newer variants in the already known drivers of lung carcinomas, which may be clinically actionable. Mutations in exons 18 to 21 of EGFR are widely characterised in literature, and rare unusual mutations in these regions are constantly being demonstrated recently. This report describes a rare exon 18 insertion variant in EGFR gene in a 61-year-old patient of non-small cell lung carcinoma, which is potentially actionable, thus highlighting the need of next generation sequencing based platforms in this era of precision medicine.