A new blood test, developed by Institute of Cancer Research (ICR) and The Royal Marsden NHS Foundation Trust, is able to detect breast cancer recurrence more than 10 months before symptoms appear or hospital scanners pick it up.
The “liquid biopsy” test screens the blood to search for cancer DNA markers that are a significant sign of the disease returning.
ICR professor of molecular oncology Nicholas Turner, who led the study said, “These new blood tests can work out which patients are at risk of relapse much more accurately than we have done before, identifying the earliest signs of relapse almost a year before the patient will clinically relapse.“
The study was carried out across 5 hospitals in 101 women with breast cancer. Samples from each patient's tumour were taken and analysed to identify mutations. From this, they were able to distinguish cancerous DNA from other DNA in the blood. A personalised blood test was then administered to determine the amount of cancerous DNA present and allow levels to be monitored.
This data was then added to data from a previous proof-of-principle study bringing the total number of test subjects to 144. Of these 144 patients, 29 of them relapsed within three years. The test detected cancerous DNA present in 23 of them, on average 10 months before they experienced any symptoms or before scans could detect it.
Turner added “We hope that by identifying relapse much earlier we will be able to treat it much more effectively than we can do now, perhaps even prevent some people from relapsing. But we will now need clinical trials to assess whether we can use these blood tests to improve patient outcome. We have launched the first of these studies already, and hope to launch large studies in the future.”
Simon Vincent, Director of Research at Breast Cancer Now, who part funded the study with Breast Cancer Care also said “This could be a really significant breakthrough. The fact that these tests are personalised to each patient to try to find out whether any cancer cells remain and are on the move is unique.”