Abstract 3016
Background
Lung carcinomas (LCs) carrying MET exon 14 skipping (exon 14Δ) mutations are responsive to a number of tyrosine kinase inhibitors. There is a need to incorporate MET analysis in the diagnostic pipeline for LC patients.
Methods
Nucleic acids were extracted from formalin-fixed paraffin-embedded archival LC samples and subjected to cDNA synthesis. This pool of genomic DNA and cDNA was sequentially tested for EGFR, ALK and MET mutations by PCR-based assays.
Results
Allele-specific PCR detected MET exon 14 skipping in 35/1415 (2.5%) EGFR mutation–negative LCs. There was a highly pronounced association with the elderly age of the patients (median age 69 years as compared to 62 years in EGFR/ALK/MET mutation-negative cases; p = 1.821e-06). 34/35 (97%) LCs with MET exon 14 skipping mutations showed preferential expression of the affected MET allele, while the wild-type transcript was almost undetectable in these tumors. In addition, we identified a subset of MET wild-type LCs, which produced normal MET transcript but also expressed residual amounts of MET exon 14Δ RNA message, probably due to alternative splicing.
Conclusions
The mere detection of MET exon 14Δ signal by allele-specific PCR does not warrant the presence of corresponding clonal MET mutation. Comparison of expression of MET exon 14Δ and wild-type alleles is essential for reliable identification of tumors carrying drug-sensitizing MET lesions.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Russian Science Foundation (grant 17-75-30027).
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5239 - Treatment patterns and outcomes for patients (pts) with anaplastic lymphoma kinase-positive (ALK+) advanced non-small-cell lung cancer (NSCLC) in US clinical practice
Presenter: Matthew Krebs
Session: Poster Display session 1
Resources:
Abstract
5595 - Is there any prognostic significance in pleural involvement and/or effusion (Ple-I/E) in patients with ALK-positive NSCLC?
Presenter: Saadettin Kilickap
Session: Poster Display session 1
Resources:
Abstract
5840 - Crizotinib in patients with advanced or metastatic ROS1-rearranged lung cancer (EUCROSS): A European phase 2 clinical trial – Updated progression-free survival, overall survival and mechanisms of resistance
Presenter: Sebastian Michels
Session: Poster Display session 1
Resources:
Abstract
1905 - NTRK1-3 Genomic Fusions in Non-Small Cell Lung Cancer (NSCLC) Determined by Comprehensive Genomic Profiling
Presenter: Sai-Hong Ou
Session: Poster Display session 1
Resources:
Abstract
4120 - Brain metastases, treatment patterns and outcomes in ROS1-positive NSCLC patients from US oncology community centers
Presenter: Matthew G Krebs
Session: Poster Display session 1
Resources:
Abstract
3764 - Patients with metastatic non-small cell lung cancer and targetable molecular alterations in Germany. Treatment and first outcome data from the prospective German Registry Platform CRISP (AIO-TRK-0315)
Presenter: Frank Griesinger
Session: Poster Display session 1
Resources:
Abstract
4070 - Crizotinib vs Platinum-based Chemotherapy as First-line Treatment for Advanced Non-small Cell Lung Cancer with Different ROS1 Fusion Variants
Presenter: Haiyan Xu
Session: Poster Display session 1
Resources:
Abstract
5528 - Genomic and clinical characterization of Non-small cell lung cancer (NSCLC) patients harboring mutations in FGFR2 and FGFR3
Presenter: Matthias Scheffler
Session: Poster Display session 1
Resources:
Abstract
3779 - The expression of HER2-gene polymorphisms -1985G>T and P1170A C>G and their association with the risk of development of lung adenocarcinoma
Presenter: Ivan Aleric
Session: Poster Display session 1
Resources:
Abstract
3020 - Circulating tumor DNA (ctDNA) analysis depicts mechanisms of resistance and tumor response to BRAF inhibitors in BRAF-mutant non-small cell lung cancer (NSCLC)
Presenter: Sandra Ortiz - Cuaran
Session: Poster Display session 1
Resources:
Abstract