Detection of EGFR mutations in patients with suspected lung cancer using paired tissue-plasma testing: a prospective comparative study with plasma ddPCR assay

Lynn Yim-Wah Shong ^1,2, Jun-Yang Deng ¹, Hoi-Hin Kwok ¹

⁰Department of Medicine, The University of Hong Kong, Hong Kong SAR, P. R. China.

Scientific Reports +

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October 28, 2024

View abstract on PubMed

Summary

Plasma droplet digital PCR (ddPCR) for EGFR mutations aids lung cancer diagnosis, especially in advanced stages. This non-invasive test shows promise as an adjunct to tissue biopsy, though accuracy in early-stage non-small cell lung cancer requires further research.

Area Of Science

Oncology
Molecular Diagnostics
Genetics

Background

Epidermal Growth Factor Receptor (EGFR) mutations are key drivers in non-small cell lung cancer (NSCLC).
Tissue biopsy for EGFR mutation detection can be invasive and may yield insufficient samples.
Plasma-based droplet digital PCR (ddPCR) offers a potential non-invasive alternative for EGFR mutation analysis.

Purpose Of The Study

To evaluate the performance of plasma ddPCR for EGFR mutation detection compared to tissue biopsy in Asian patients with suspected lung cancer.
To assess the diagnostic accuracy and concordance of plasma ddPCR across different stages of NSCLC.

Main Methods

Consecutive patients with suspected lung cancer underwent concurrent peripheral blood collection and tissue biopsy.
EGFR mutations were analyzed in tissue using real-time PCR and in plasma using ddPCR.
Diagnostic yield and concordance rates between plasma ddPCR and tissue testing were calculated.

Main Results

EGFR mutations were detected in 13.4% of plasma samples versus 44.3% in tissue samples from 202 newly diagnosed lung cancer patients.
Plasma ddPCR sensitivity for EGFR mutations increased with NSCLC stage (25.0% Stage III, 56.3% Stage IVA, 75.0% Stage IVB).
Concordance between plasma ddPCR and tissue testing improved with advanced stages (41.9% Stages I/II, 71.9% Stage III, 86.3% Stage IV).

Conclusions

Plasma ddPCR is a valuable, non-invasive adjunct for EGFR mutation detection in advanced-stage NSCLC.
The assay shows high specificity but limited sensitivity in early-stage NSCLC.
Further research is needed to enhance the accuracy of plasma ddPCR for early-stage lung cancer diagnosis.

Keywords:

EGFR mutations Lung cancer NSCLC Plasma ddPCR