MET Amplification in Non-Small Cell Lung Cancer (NSCLC)-A Consecutive Evaluation Using Next-Generation Sequencing...

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• MET gene copy number (GCN) alterations occur in 1-3% of non-small cell lung cancer (NSCLC) cases.
• MET GCN can arise from de novo amplification or secondary resistance to targeted therapies.
• Fluorescence in situ hybridization (FISH) is the current standard for MET GCN evaluation.

Purpose of the Study:

• To determine if amplicon-based next-generation sequencing (NGS) can fully replace FISH for classifying MET GCN status in NSCLC.
• To assess the concordance between FISH and NGS in detecting MET GCN alterations.

Main Methods:

• Retrospective analysis of 205 NSCLC cases.
• Comparison of MET GCN status determined by FISH and an amplicon-based NGS assay.
• Evaluation of concordance rates based on different GCN thresholds.

Main Results:

• Only 43.7% (9/16) of high-level MET amplified cases by FISH were classified as amplified by NGS.
• Concordance between FISH and NGS was highest (80%) for cases with MET GCN > 10.
• NGS detected high-level MET amplification (GCN > 10) but missed other amplification patterns.

Conclusions:

• Amplicon-based NGS can detect high-level MET gene amplification (GCN > 10) in NSCLC.
• NGS is not a complete replacement for FISH in evaluating all MET GCN alterations, particularly therapy-induced resistance.
• Further optimization of NGS assays is needed for comprehensive MET GCN assessment in NSCLC.