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
174P - Progression of computer aided diagnosis on gastric cancer
Presenter: Yingyan Yu
Session: Poster display session
Resources:
Abstract
175P - Hypermethylation of the PCDHB15 promoter predicts the prognosis in gastric cancer
Presenter: Yu-ting Lee
Session: Poster display session
Resources:
Abstract
176P - DCLK1 promotes tumour invasion and metastasis through epithelial-mesenchymal transition and the MEK/ERK pathway in esophageal squamous cell carcinoma
Presenter: Jiannan Yao
Session: Poster display session
Resources:
Abstract
177P - Comparison of nab-paclitaxel plus ramcirumab and paclitaxel plus ramcirumab in patients with pretreated metastatic gastric cancer
Presenter: Yosuke Horita
Session: Poster display session
Resources:
Abstract
178P - Chief cell in stomach have stem cell activity and potential to develop gastric cancer
Presenter: Akihiro Yamamura
Session: Poster display session
Resources:
Abstract
179P - Postoperative Adjuvant transarterial chemoembolization versus surgery alone for resected hepatocellular carcinoma: A propensity-score matching study
Presenter: Mingyu Chen
Session: Poster display session
Resources:
Abstract
180P - LHPP inhibit the cell proliferation and EMT via the TGFβ/SMAD3 signaling pathway in iCCA
Presenter: Dan Wang
Session: Poster display session
Resources:
Abstract
181P - The emerging role of third-line gemcitabine plus nab-paclitaxel in advanced pancreatic adenocarcinoma
Presenter: Andrew Dean
Session: Poster display session
Resources:
Abstract
182P - Durable response to second-line m-FOLFIRINOX for advanced pancreatic adenocarcinoma in patients with performance status of two or less
Presenter: Adarsh Das
Session: Poster display session
Resources:
Abstract
183P - Epidemiologic profile of gastric cancer in East Azerbaijan, Iran: 2 years population-based cancer registry results
Presenter: Pooneh Jabbaripour
Session: Poster display session
Resources:
Abstract