Abstract 500P
Background
With the advances of next-generation sequencing (NGS), compound EGFR mutations were more frequently observed. Prior studies reported that patients with compound EGFR mutations showed poor clinical outcome. However, molecular and clinical features of NSCLC patients harboring such mutations were poorly investigated.
Methods
A total of 1091 primary NSCLC patients were enrolled. Variants of EGFR and other driver genes were analyzed by NGS. EGFR exon 19 deletion (19 del) and L858R mutations were defined as common sensitizing mutations; EGFR G719S/C/A mutations were defined as uncommon sensitizing mutations; other mutations were defined as rare mutations. Patients were divided as follows: common sensitizing and rare mutations (group A); uncommon sensitizing and rare mutations (group B); double rare mutations (group C).
Results
Overall, EGFR mutations were detected in 418 patients (38.3%), and 76 cases (7.0%) carried compound EGFR mutations. Frequencies of group A, B and C were 76.3%, 18.4% and 5.3%, respectively, indicating compound mutations mainly consist of sensitizing and atypical mutations. Compound mutations were more frequently observed in young patients (p = 0.017), and distributions of the three groups were different between early and adavanced stages (p = 0.032). According to types of common sensitizing mutations, rate of compound mutations harboring EGFR L858R alteration was strikingly higher than that carrying EGFR 19 del alteration (p = 0.039). Further analysis demonstrated that frequency of EGFR T790M mutation among the three groups showed significant difference (p = 0.031). Genomic data revealed TP53 mutations markedly coexisted with compound mutations compared with single mutation (p = 0.03). Moreover, relative EGFR mutant allele frequency (rMAF) of group A, calculated as MAF of EGFR sensitizing mutations / MAF of EGFR rare mutations, was higher than that of group B (p = 0.007).
Conclusions
This study comprehensively explored the population characteristics of compound EGFR mutations from a large cohort of primary NSCLC patients, which will be helpful to guide personalized therapy and promote the clinical management of this population.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
H. Cheng: Honoraria (self): Beijing Acornmed Biotechnology Co., Ltd. H. Wang: Honoraria (self): Beijing Acornmed Biotechnology Co., Ltd. F. Lou: Honoraria (self): Beijing Acornmed Biotechnology Co., Ltd. S. Cao: Honoraria (self): Beijing Acornmed Biotechnology Co., Ltd. All other authors have declared no conflicts of interest.
Resources from the same session
457P - The prevalence of vitamin D deficiency in Thai cancer patients, its dynamics and association with cancer survival
Presenter: Chavapon Ngokngarm
Session: Poster display session
Resources:
Abstract
458P - Mutation tracking in circulating tumour DNA predicts relapse in completely resected EGFR-mutated NSCLC
Presenter: Martin Filipits
Session: Poster display session
Resources:
Abstract
460P - Mendelian randomization study showed no causality between metformin use and lung cancer risk
Presenter: Jiayi Shen
Session: Poster display session
Resources:
Abstract
461P - Blood trace minerals and lung cancer: A Mendelian randomization study
Presenter: Wei Xian
Session: Poster display session
Resources:
Abstract
463P - Prediction of invasiveness in lung adenocarcinoma using machine learning algorithm based on 3D-CT imaging
Presenter: Yusuke Saeki
Session: Poster display session
Resources:
Abstract
459P - Fish intake, dietary polyunsaturated fatty acids, and lung cancer: systematic review and dose-response meta-analysis of 1.7 million men and women
Presenter: Chao Cao
Session: Poster display session
Resources:
Abstract
462P - Usefulness for prevention of postoperative cerebrovascular complications in patients with lung cancer using carotid ultrasonography
Presenter: Sadanori Takeo
Session: Poster display session
Resources:
Abstract
468P - Histological type analysis of 10-year follow-up of WJTOG0105: A phase III study comparing second- and third-generation regimens with concurrent thoracic radiotherapy in unresectable stage III non-small cell lung cancer
Presenter: Masahiro Tsuboi
Session: Poster display session
Resources:
Abstract
469P - Comparison of combined chemoradiotherapy regimens; Paclitaxel plus carboplatin and cisplatin plus etoposide for locally advanced non-small cell lung cancer: A randomised phase III trial
Presenter: Alper Ata
Session: Poster display session
Resources:
Abstract
472P - Integration of expression rate and absolute cell counts of PD-1+ stromal tumour-infiltrating lymphocytes: Prognostic significance in esophageal squamous cell carcinoma
Presenter: Qingkun Song
Session: Poster display session
Resources:
Abstract