A simple blood test could spot breast cancer five years before any symptoms, saving thousands of lives. Experts said the method was “promising” and could be used to screen women, replacing mammograms and allow treatment to start far earlier, when it is most likely to succeed. Breast cancer is the most common cancer in women, with around 55,000 women diagnosed annually, and around 11,500 deaths. The new research, presented at the National Cancer Research Institute’s conference in Glasgow, found that a blood test could identify changes in the body’s immune response to substances produced by tumour cells. Scientists said larger trials were expected to improve the accuracy of the test, which could become widely available within four years. Cancer cells produce proteins called antigens that trigger the body to make antibodies against them. These are called “autoantibodies”. The pilot study by the University of Nottingham took blood samples from 90 breast cancer patients at the time they were diagnosed with breast cancer and matched them with samples taken from 90 patients without breast cancer. Screening technology was used to find the presence of autoantibodies linked to breast cancer. Presenting the research at the NCRI Conference, researcher Daniyah Alfattani said: “The results of our study showed that breast cancer does induce autoantibodies against panels of specific tumour-associated antigens. We were able to detect cancer with reasonable accuracy by identifying these autoantibodies in the blood.” The most successful technique was able to identify disease in 37 per cent of cases with cancer, and rule it out, in 79 per cent of the control group. About | Breast cancer “We need to develop and further validate this test,” said Ms Alfattani. “However, these results are encouraging and indicate that it’s possible to detect a signal for early breast cancer. Once we have improved the accuracy of the test, then it opens the possibility of using a simple blood test to improve early detection of the disease.” The researchers are now testing samples from 800 patients and expect the accuracy of the test to improve with these larger numbers. “A blood test for early breast cancer detection would be cost effective,” Ms Alfattani said. “It would also be an easier screening method to implement compared to current methods, such as mammography.” Researchers said that with sufficient investment, tests could be available in clinics in four to five years. Similar methods are being tested for lung cancer, pancreatic, bowel and liver disease. “A blood test capable of detecting any of these cancers at an early stage is the over-riding objective of our work,” Ms Alfattani said. Dr Kotryna Temcinaite, from charity Breast Cancer Now, said: “It’s really promising that a simple blood test could in future help clinicians detect autoantibodies that may arise before breast tumours develop. While these are early findings, it’s exciting that testing for these autoantibodies could potentially help detect breast cancer earlier or identify women who may benefit from being monitored more closely.” Dr Iain Frame, chief executive of NCRI said: “The results from this pilot study for a blood test to detect early breast cancer are promising and build on this research group’s expertise in other cancers, such as lung cancer. It’s obviously early days but we look forward to seeing the results from the larger group of patients that are now being investigated.” Prof Paul Pharoah, Professor of Cancer Epidemiology, University of Cambridge, said early tests for cancer were a major research goal, but said the study did not provide evidence that breast cancer could be spotted five years before symptoms. He expressed caution about the significance of the results, saying the current sensitivity of the test was too low to be used as an early detection test.