The small study, funded by Cancer Research UK, showed that the blood test was able to detect 89% of all relapses, on average an impressive 8.9 months quicker than imaging.
The blood test is called Signatera, and developed by genetic testing company Natera. It uses a molecular residual disease (MRD) assessment to detect even trace amounts of the mutant DNA released from dying tumours, enabling such early detection of relapse.
The study, called ‘Personalized Detection of Circulating Tumor DNA Antedates Breast Cancer Metastatic Recurrence’, was published in Clinical Cancer Research. It included a cross section of breast cancer subtypes, including HER2-positive, hormone receptor-positive, and triple-negative. Blood samples were collected every six months for up to four years from each patient, and results were correlated with radiographic and clinical outcomes.
Dr David Crosby, head of early detection at Cancer Research UK, said: “The initial results of this study are encouraging. Monitoring when breast cancer returns in some patients is an important step in improving survival. Using circulating tumour DNA from a blood test is an emerging and promising method, although it requires further validation. I look forward to seeing the next steps of this research using a larger group of patients.”
Breast cancer is the second leading cause of cancer death in women, with approximately 55,000 women diagnosed with invasive breast cancer every year in the United Kingdom, and two million cases estimated worldwide.