Abstract 5838: The landscape of EGFR exon 20 insertion mutations in Chinese patients with non-small cell lung cancer

Abstract

Abstract Background: The epidermal growth factor receptor (EGFR) is one of the most commonly altered genes in non-small cell lung cancer(NSCLC). Of these, insertion mutation in 20 exon (Ex20ins) of the EGFR occurs less frequently. In comparison with the common EGFR mutations (19Del/L858R), the NSCLC patients with Ex20ins have a worse prognosis. Recently, the FDA approved targeted oral therapeutic agent for NSCLC patients with EX20ins mutation, which has markedly improved their survival. Here we carry out a complete analysis of the frequency and types of EGFR 20 Exon insertion mutations in the large-scale NSCLC cohort of the Chinese population. Methods: From January 2020 to October 2021, a total of 4,091 patients were confirmed as NSCLC were included in the study. The Next-generation sequencing was utilized for detecting genetic mutations. Results: Among the 4,091 NSCLC patients, 2,411 (58.9%) experienced EGFR mutations. In which we identified 90 patients(2.2%) with Ex20ins. All of the Ex20ins were localized between amino acids S767-V774, and after C-helix of the EGFR kinase domain. Different from the exon 19 deletion, we found that Ex20ins exhibits various types of mutations. A total of 34 Ex20ins types were detected, with the most common A767_V769dupASV and S768_D770dupSVD mutations, accounting for 26% and 22.2% respectively. In addition, H773dupH (6.67%), H773_V774dupHV(5.56%), H773_V774insAH (2.22%), D770_N771insG (2.22%), and N771_P772insG(2.22%) were also observed in the NSCLC patients. Conclusions: We described the landscape of EGFR Ex20ins in Chinese NSCLC patients cohort. Based on the large sample size, the frequency of the Ex20ins mutation in Chinese NSCLC patients was 2.2%, and the types of EGFR Ex20ins mutation were highly heterogeneous. Citation Format: shun xu, Zhichao Fu. The landscape of EGFR exon 20 insertion mutations in Chinese patients with non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5838.