Unlocking the Value of Liquid Biopsy Testing in Cancer Pathways

The promise and complexity of liquid biopsy in cancer care

Circulating tumour DNA (ctDNA) testing has the potential to transform cancer care by giving clinicians access to genomic information through a simple blood test. Compared with traditional tissue biopsies, liquid biopsies can be less invasive, faster, and easier to repeat, supporting earlier diagnosis and more personalised treatment decisions. However, the value of introducing a new diagnostic technology depends on both the test and where it is used in the pathway, which patients are tested, what decisions it changes, and whether it replaces or simply adds to existing activity.

Reviewing potential indications for ctDNA testing

Edge Health was asked by the Circulating Biomarker Network of Excellence to review five potential indications for liquid biopsy testing: cancer of unknown primary, hepato-pancreato-biliary cancer, germ cell tumours, advanced breast cancer, and paediatric cancer. Across each pathway, we worked with clinical teams to understand current practice, identify where ctDNA or other circulating biomarker tests could be introduced, and appraise the likely benefits for patients and the NHS.

A health economic approach focused on clinical decision points

Our health economic approach helped move the discussion beyond a simple “does the test work?” question. Instead, it focused on the clinical decision point at which testing could add the most value. In some pathways, this meant reducing repeat tissue biopsies and diagnostic delays. In others, it meant supporting surveillance, reducing the need for imaging, or enabling access to targeted therapies where tissue-based testing was limited.

The findings showed that there is no single route to implementation. The economic and clinical case for liquid biopsy testing varies significantly by cancer type, pathway design, test cost, and the availability of targeted treatments. This makes careful pathway mapping and scenario modelling essential before adoption at scale.

Across the five indications, the work highlighted a range of potential benefits, from reducing diagnostic loops and invasive procedures, to improving surveillance and supporting access to targeted therapies. It also showed where further evidence is needed before benefits can be fully quantified, particularly in pathways where clinical practice is still evolving.

As genomic medicine becomes increasingly embedded in NHS cancer care, robust evaluation will be critical. By combining clinical engagement, evidence review and health economic modelling, Edge Health helped provide a practical framework for understanding not just whether liquid biopsy testing should be introduced, but how it can be introduced in a way that delivers the greatest benefit for patients, clinicians and the wider health system.

“What was particularly valuable about Edge Health’s approach was that it helped clinical teams move from the broad promise of ctDNA testing to practical decisions about implementation. The health economic modelling showed where in each pathway testing could add the most benefit, helping us to focus on how to maximise value for patients and the NHS.”
Professor Michael Hubank
Circulating Biomarker Network of Excellence

See our full report for more detail: https://www.edgehealth.co.uk/reports/