Postoperative prognosis in patients with NSCLC with different EGFR mutation sites.

person Chao Dong The First Affiliated Hospital of Kunming Medical University, Kunming, China info_outline Chao Dong, Hushan Zhang, Weiqing Liu, Deyu Kong, Xiao Chen, Fei Mo, Jun Deng, Ying Qian

Authors person Chao Dong The First Affiliated Hospital of Kunming Medical University, Kunming, China info_outline Chao Dong, Hushan Zhang, Weiqing Liu, Deyu Kong, Xiao Chen, Fei Mo, Jun Deng, Ying Qian Organizations The First Affiliated Hospital of Kunming Medical University, Kunming, China, 3D Medicines Co. Ltd., Shanghai, China, The First Affiliated Hospital of Kunming Medical Unversity, Kunming, China, The first affiliated hospital of Kunming medical university, Kunming, China, The First Affliated Hospital of Kunming Medical University, Kunming, China, The First Affliated Hopital of Kunming Medical University, Kunming, China Abstract Disclosures Research Funding No funding received None. Background: Lung cancer can be divided into small cell lung cancer and non-small cell lung cancer. At the same time, non-small cell lung cancer can be divided into non-small cell lung cancer with different molecular mutations. Among them, the EGFR mutation accounts for about 50% of the patients with non-small cell lung cancer in China, which is a large group of patients. The EGFR mutation has many sites and many forms of mutational subtypes, including common mutations such as L858R, and rare mutations. Although the proportion of rare mutations is small, it is still different from common mutations in patients with TKI treatment and immunity. Methods: This study collected and analyzed the data from Formalin-Fixed Paraffin-Embedded (FFPE) tissues of 330 NSCLC patients which received surgery and underwent a targeted next-generation sequencing (NGS) assay performed by 3DMed Clinical Laboratory Inc., a College of American Pathologists (CAP) certified and Clinical Laboratory Improvement Amendments (CLIA) certified laboratory of 3D Medicines Inc. between January, 2019 and June, 2022 in China, to obtain a comprehensive molecular profile of EGFR mutations. genomic alterations, tumor mutational burden (TMB) and PD-L1 expression were analyzed. Gene mutation and TMB level were analyzed by NGS, detected PD-L1 expression by using Dako PD-L1 IHC 22C3 pharmDx, Tumor Proportion Score (TPS) was used to determine expression of PD-L1. Finally, the postoperative follow-up data were also collected and analyzed in this study. Results: Therefore, we retrospectively analyzed the tissue samples of patients with non-small cell lung cancer who received surgical treatment, and carried out NGS detection and analysis, as well as postoperative follow-up. Among them, patients with EGFR mutations accounted for 51.2%. We further analyzed the TMB and PD-L1 expression levels of different EGFR mutation subtypes. First, we found that different EGFR mutation sites, whether common mutations such as L859R, 19del or unusual mutations such as S768I, There is no difference in the prognosis after operation, but it is very significant that our results show that there are two or more EGFR mutations at the same time. Conclusions: NSCLC with EGFR mutation is a very large group of patients, which should be further subdivided into different subtypes according to different EGFR mutation sites, and should perform individualized management. This study found that patients with two or more EGFR mutations and patients with EGFR single site mutations are different types of NSCLC, with different postoperative prognosis, and it may be related to the differences in the expression levels of TMB and PD-L1, which is a direction worthy of further exploration in the future.