Combined ctDNA Testing Improved Lung Cancer Surveillance
Researchers found that using two types of blood tests together can better track molecular residual disease in lung cancer patients.
Updated on Oct. 8, 2026 in Cancer
Live Poll
Would you prefer using multiple diagnostic testing approaches for cancer surveillance rather than just one?
By combining tumor-informed and tissue-agnostic ctDNA assays, doctors can detect tumor recurrence more effectively than by using a single method alone. This approach ensures Chicago residents with lung cancer have more comprehensive monitoring options, particularly when surgical tissue samples are limited.
Why it matters
Cancer surveillance often relies on tissue-informed assays that can be hindered if diagnostic biopsies exhaust limited tissue samples. Using these tests in tandem helps overcome these limitations, potentially catching more cases of molecular residual disease.
Comparative research indicates that while both tumor-informed and tissue-agnostic assays effectively detect molecular residual disease, they capture different cases. Each assay type detects markers that the other may miss in lung cancer patients.
The players
Young Kwang Chae
An oncology researcher at Northwestern University specializing in lung cancer surveillance and ctDNA assay comparisons.
Northwestern University
A Chicago-based academic research institution where this comparative clinical surveillance study and practice were conducted.
The details
Tumor-informed assays function by identifying specific biomarkers derived directly from an individual patient's tumor tissue, typically gathered during surgery or initial biopsy. In contrast, tissue-agnostic assays utilize plasma-only analysis algorithms to identify tumor-shed DNA without requiring an existing tissue sample. By comparing cell-free DNA against germline and library data, the agnostic method serves as a crucial backup when tissue is depleted by immunohistochemistry workups.
Timeline
Blood-based tumor-informed surveillance assays are currently performed every 3 months.
Health Landscape
This development marks a shift in precision oncology by moving beyond reliance on single-modality blood tests for postsurgical monitoring. It aligns with the broader move at Northwestern University to optimize how clinicians manage limited biopsy tissue in complex cancer surveillance.
Patients undergoing postsurgical lung cancer monitoring should consult their physician about whether their surveillance plan includes both tumor-informed and tissue-agnostic assays. This dual approach is particularly relevant for those whose tissue samples may be limited due to prior testing.
The takeaway
Using multiple ctDNA testing methods provides a more reliable picture of lung cancer recurrence by ensuring critical tumor data is captured even when tissue is scarce. Patients should talk with their care team to confirm if their blood-based surveillance protocol incorporates these complementary tests.
Further reading
For more information on monitoring, visit our Cancer section for the latest guidance on surveillance.
Source note: This article includes information reported by OncLive.
Live Poll
Would you prefer using multiple diagnostic testing approaches for cancer surveillance rather than just one?
