November 3, 2019

expert reaction to conference presentation about a blood test for early detection of breast cancer

A conference presentation, at the 2019 NCRI Cancer Conference, reports on a possible blood test to detect early signs of breast cancer. 

Dr Jeremy Carlton, Wellcome Trust Senior Research Fellow, School of Cancer and Pharmaceutical Sciences, King’s College London & The Francis Crick Institute, said:

“The development of non-invasive blood tests to detect early signs of cancer is an important goal in cancer research. Here, the authors took blood from 90 patients with breast cancer and 90 patients without breast cancer and used a test to detect whether the body’s immune system was trying to fight any cancer present. However, this test failed to detect cancer in 60-70% of patients that were known to have cancer. Importantly, this test also mis-reported cancer in around 20% of patients known to be cancer-free. The claims in the press release that this test could be used to detect cancer 5 years before clinical diagnosis were not supported as the authors did not appear to examine any samples obtained 5-years before clinical diagnosis. In short, this study is too preliminary to support the claims made in the press release and it will be important to ensure that any future diagnostic test is as accurate, sensitive and reliable as possible.”

Prof Paul Pharoah, Professor of Cancer Epidemiology, University of Cambridge, said:

“The search for a blood test that is capable of detecting cancer very early, before it causes any symptoms is one of the major goals of research in early cancer detection.

“This press release claims ‘Breast cancer could be detected up to five years before there are any clinical signs of it’ using a new blood test. However, there are no data at all presented to suggest that this claim might be valid.  The investigators have evaluated the test on 90 breast cancer patients and 9 individuals without breast cancer, but they do not appear to have tested it on samples from breast cancer patients from 5 years before they were diagnosed – which is what would be needed to justify the claim.

“Furthermore, even in breast cancer patients the sensitivity of the tests in this study is far too low for it to be used as an early detection test – it correctly identifies cancer in only 35% of the cancer patients.  So not only does it not detect cancer five years before it could be clinically diagnosed, it missed 65% of clinically diagnosed cancers.

“These are clearly very preliminary data and a lot more research would be needed before any claim can be made that this is likely to represent a meaningful advance in the early detection of cancer.  I think it is too soon to even claim that the research is promising.”

Prof Lawrence Young, Professor of Molecular Oncology, University of Warwick, said:

“There is increasing interest in developing blood tests for the early detection of cancer. These tests detect a combination of different factors, usually tumour DNA and protein markers. This new research builds on previous work showing that the body’s immune system generates antibodies to specific proteins (antigens) in cancer cells that can be used as a way of detecting cancer. Using a panel of antigens, the new research shows that this test can be used to identify 37% of patients with breast cancer at the time of first diagnosis. While this is encouraging research, it is too soon to claim this test could be used to screen for early breast cancer. More work is needed to increase the efficiency and sensitivity of cancer detection.”

‘Clinical utility of autoantibodies in early detection of breast cancer’ by Alfattani was presented at the 2019 NCRI Cancer Conference on Sunday 3^rd November.

There is no paper as this is not published work.

Declared interests

Prof Paul Pharoah: “I have no conflicts of interest to declare.”

Prof Lawrence Young: “I have no conflicts of interest to declare.”

None others received.