Circulating tumour DNA in EGFR-mutant non-small-cell lung cancer

Area of Science:

• Oncology
• Molecular Diagnostics
• Genetics

Background:

• Targeted therapy for non-small cell lung cancer (NSCLC) necessitates routine molecular diagnosis of EGFR mutations.
• Tumor tissue acquisition for biomarker testing, particularly during re-biopsy, poses significant challenges.
• Circulating cell-free tumor-derived DNA (ctDNA) in plasma presents a viable alternative source for tumor DNA.

Purpose of the Study:

• To highlight the importance of molecular diagnosis for EGFR mutations in NSCLC patient management.
• To discuss the challenges associated with obtaining tumor tissue for biomarker testing.
• To explore the potential of ctDNA as an alternative source for tumor DNA analysis.

Main Methods:

• Review of current literature on ctDNA analysis for EGFR mutations in NSCLC.
• Discussion of the performance characteristics of various digital and non-digital platforms for ctDNA detection.
• Emphasis on the need for standardized approaches in ctDNA analysis.

Main Results:

• ctDNA is present in low quantities in plasma but offers convenience in sample acquisition.
• Detection methods for ctDNA are increasing in reliability.
• Variability in performance characteristics of different platforms necessitates standardization.

Conclusions:

• ctDNA analysis is a promising approach for detecting EGFR sensitizing and resistance mutations, including T790M.
• Standardized ctDNA platforms are needed to serve as reliable clinical tools.
• ctDNA can inform tumor burden assessment, resistance mechanism identification, and therapy monitoring.