New research has shown that more people could benefit from a new type of blood test that can predict the return of breast cancer, months before it’s picked up on a scan.
The new test would be cheaper and easier to use as it does not rely on analysing the tumour tissue collected at diagnosis.
Accurately predicting which tumours are likely to come back after initial treatment could help identify who may need to be treated more, while reassuring people at low risk. When breast cancer comes back and spreads to other parts of the body, it’s known as metastatic breast cancer. While metastatic breast cancer can be treated, it can’t currently be cured.
Liquid biopsies are able to spot breast cancer coming back before the tumours become visible on hospital scans. These tests, which look for tiny fragments of tumour DNA in the blood, are currently highly personalised and require information from a tumour biopsy to develop a tailored blood test for each person.
Tumour-informed tests rely on having enough suitable tumour tissue from the original diagnosis to create a personalised blood test. Sometimes there isn’t enough tissue available, too little tumour or DNA remains after the initial testing, or the test cannot be successfully developed.
Researchers at The Institute of Cancer Research, London, and the Royal Marsden NHS Foundation Trust, compared these liquid biopsies with a new type of test, called a ‘tissue-free’ test. They showed that the new test works just as well as the ‘tissue-informed’ test. As the new test doesn’t require prior information from the tumour, this could unlock a widespread adoption of liquid biopsies, if they are shown to improve outcomes for people.
To directly compare the two liquid biopsy approaches, researchers at the Breast Cancer Now Toby Robins Research Centre at The Institute of Cancer Research (ICR) studied blood and tumour samples collected as part of the C-TRAK TN clinical trial. This was the first study to investigate whether monitoring cancer DNA in the blood could predict recurrence in people with early triple negative breast cancer, a more aggressive and harder to treat type, who were at moderate to high risk of their cancer returning.
The new findings, published in JAMA Oncology confirm that detecting cancer DNA in the blood is a strong indicator that someone’s disease would return. On average, the blood tests predicted recurrence around 7.9 months before the cancer showed up on standard scans.
The team found that the new tissue-free blood test performed just as well as more complex approaches that reply on the information from tumour tissue samples. The findings bring researchers a step closer to using blood tests to personalise follow-up care. If ongoing studies show that acting on these early warning signs helps to stop cancer progressing, doctors could identify people who need extra treatment before the disease spreads and becomes incurable.
Earlier treatment could help stop metastatic breast cancer from developing. More accurate blood tests could also reassure people at lower risk that their cancer is less likely to return, helping ease the anxiety many experience after treatment.
The research received funding from Breast Cancer Now, Guardant Health, the ICR Clinical Trials and Statistics Unit (ICR-CTSU), Le Cure (Royal Marsden Cancer Charity) and the National Institute of Health Research Biomedical Research Centre (NIHR BRC) at the Royal Marsden and the ICR.
Dr Isaac Garcia-Murillas, Senior Staff Scientist in the Molecular Oncology Group at The Institute of Cancer Research, London, said: "This study helps us better understand which blood tests are most effective at detecting the earliest signs that breast cancer has returned. We've shown that this tissue-free approach performs well and could make ctDNA testing available to more patients, particularly when a tumour sample isn't available. These findings add to growing evidence that ctDNA is a powerful way to identify people at high risk of their cancer returning. If ongoing clinical trials show that acting on these early warning signs improves patient outcomes, this type of blood test could one day become part of routine follow-up after breast cancer treatment, helping doctors personalise care and intervene earlier for those who need it most."
- Cunningham N, Cutts RJ, Swift C, et al. Tissue-Free vs Tumor-Informed ctDNA Assays for Molecular Residual Disease Detection in Early Triple Negative Breast Cancer. JAMA Oncol. Published online August 13, 2026. doi:10.1001/jamaoncol.2026.2833