Researchers develop highly sensitive blood test for cancer

Researchers have developed a new way of analysing cancer patients’ blood for evidence of the disease that could be up to ten times more sensitive than previous methods.

The new approach could drive the development of new tests able to more accurately determine the likelihood of disease relapse and even pinprick tests for home monitoring.

The research, funded by Cancer Research UK and published in Science Translational Medicine, assessed a technique using personalised genetic testing of a patient’s tumour to search blood samples for hundreds of different genetic mutations in circulating tumour DNA (ctDNA).

Utilising new methods of analysing the data 'to remove background noise and enhance the signal', the team were able to reach a level of sensitivity that in some cases could find one mutant DNA molecule amongst a million pieces of DNA – around ten times more sensitive than previous methods.

“Personalised tests that can detect if cancer is still present, or find it early if it is returning, are now being tested in clinical trials,” said Dr Nitzan Rosenfeld, senior group leader at the Cancer Research UK Cambridge Institute who led the research team at the University of Cambridge.

“Whilst this may be several years away from clinical use, our research shows what is possible when we push such approaches to an extreme. It demonstrates that the levels of sensitivity we’ve come to accept in recent years in relation to testing for ctDNA can be dramatically improved.

“At present this is still experimental, but technology is advancing rapidly, and in the near future tests with such sensitivity could make a real difference to patients.”

In ongoing studies funded by Cancer Research UK, the team and its collaborators plan to use this method to measure ctDNA levels in individuals at high risk of developing cancer to help refine future tests for cancer early detection.

“Liquid biopsies have the potential to revolutionise all aspects of cancer care, from early detection to personalised treatment and monitoring,” said Michelle Mitchell, chief executive of Cancer Research UK. “As a field that relies heavily on technology, this kind of proof-of-concept research is incredibly important for us to invest in as a charity, as it’s what makes potential future leaps in the use of liquid biopsies possible, and ultimately save more lives.”