NSCLC Digital PCR Panel Returns Low-Input Sample Results Where Sequencing Fails.

Area of Science:

• Oncology
• Molecular Diagnostics
• Genetics

Background:

• Molecular diagnostics have improved non-small cell lung cancer (NSCLC) survival rates.
• However, over half of NSCLC patients in the US lack adequate molecular testing.
• This gap highlights a need for more sensitive and accessible diagnostic methods.

Purpose of the Study:

• To investigate the relationship between nucleic acid input quantity, molecular testing methodology, and test success rates.
• To compare the performance of digital PCR (dPCR) and next-generation sequencing (NGS) using low-input samples.
• To evaluate the accuracy of dPCR for detecting clinically relevant NSCLC mutations.

Main Methods:

• Utilized a shared set of low-input reference test materials (n=3).
• Compared a hybrid capture-based NGS assay with a multiplexed dPCR panel.
• Conducted dilution studies with DNA (1-40 ng) and RNA (2.5-20 ng).
• Assessed performance on 23 banked clinical samples.

Main Results:

• dPCR demonstrated high sensitivity and specificity across a wide range of low-input DNA and RNA.
• NGS exhibited up to an 86% loss in sensitivity with serially diluted samples.
• dPCR showed high positive predictive agreement (>95%) at low input levels (15/7.5 ng DNA/RNA).

Conclusions:

• Digital PCR is a sensitive and accurate method for identifying NSCLC mutations, even with limited nucleic acid input.
• dPCR offers a viable alternative to NGS for molecular testing when sample quality or quantity is a concern.
• Improving molecular testing accessibility can enhance patient care for NSCLC.