A new blood test could detect breast cancer up to five years before there are any clinical signs of the disease. The test identifies the body’s immune response to substances produced by tumor cells according to new research presented at the 2019 NCRI Cancer Conference. Cancer cells produce proteins called antigens that trigger the body to make antibodies against them — autoantibodies. Researchers at the University of Nottingham (UK) have found that these tumor-associated antigens (TAAs) are good indicators of cancer, and now they have developed panels of TAAs that are known already to be associated with breast cancer to detect whether or not there are autoantibodies against them in blood samples taken from patients. Researchers wanted to know if they could detect the presence of specific auto-antibodies in patients and show whether they had been triggered by antigens from tumour cells. So the team took blood samples from 90 patients newly diagnosed with breast cancer. They compared them with samples taken from a control group of 90 patients without breast cancer. Finally, the group screened the blood samples to see if they could detect auto-antibodies triggered by tumour antigens. The researchers correctly identified breast cancer in 37% of blood samples taken from affected patients. Crucially, they were also able to show that there was no cancer in 79% of samples from the control group. The results are considered to be highly encouraging by the group, which says they indicate that it will be possible to detect early breast cancer this way. “The results of our study show that breast cancer does induce auto-antibodies against specific tumour-associated antigens,” said Daniyah Alfattani, one of the Nottingham team. “We were able to detect cancer with reasonable accuracy by identifying these auto-antibodies in the blood. 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,” added Alfattani, who will present the study at Sunday’s National Cancer Research Institute annual conference.