EP1.03-07 Prevalence and Clinicopathological Characteristics of EIF1AX Mutations in Chinese Patients with Non-Small Cell Lung Cancer

Abstract

The EIF1AX gene was recently described as a new thyroid cancer-related gene. Its mutations were mainly reported in poorly differentiated (PDTC) and anaplastic thyroid cancers (ATC), but also in well-differentiated thyroid cancer (WDTC) and in benign thyroid lesions, although less frequently. The prevalence of these mutations in non-small-cell lung cancer (NSCLC) is unknown. The aim of this study is to investigate mutations and prognosis of NSCLC harboring EIF1AX mutations. A total of 923 patients with non-small-cell lung cancer were recruited between July 2012 and December 2016. The status of EIF1AX mutations and other genes were detected by next generation sequencing. EIF1AX gene mutation rate was 1.30% (12/923) in non-small cell lung cancer, including D125N (1 patient), G6D (1 patient), R14G (1 patient), G15D (1 patient), W70C (1 patient), K3N (1 patient), G9D (1 patient), R13P (1 patient), R14S (1 patient), R57G (1 patient), G135E (1 patient), and P2L (1 patient), and median overall survival (OS) for these patients was 20.0 months. Among them, all patients were EIF1AX gene with co-occurring mutations. Among them, 11 patients with co-occurring mutations had a median OS of 20.0 months, and OS of one patient without complex mutations was 19.8 months. No statistically significant difference was found between the two groups (P=0.84). Briefly, patients with (n=2) or without (n=10) co-occurring TP53 mutations had a median OS of 14.0 months and 20.0 months respectively (P=0.87); patients with (n=2) or without (n=10) co-occurring STK11 mutations had a median OS of 4.0 months and 20.0 months respectively (P=0.02); patients with (n=3) or without (n=9) co-occurring NRAS mutations had a median OS of 4.0 months and 20.0 months respectively (P=0.17); patients with (n=3) or without (n=9) co-occurring KRAS mutations had a median OS of not up to now and 20.0 months respectively (P=0.88). There is no significant difference of molecular features in EIF1AX gene mutations in NSCLC. Patients with complex mutations benefited more from therapy than those with single mutations. Next generation sequencing provides a simplified strategy and reasonably high detection rate for EIF1AX mutation, which suggested application of the strategies into clinical molecular diagnostics.