Scientists have developed a DNA test that may diagnose fatal breast cancer one year earlier than current methods.
Changes in a part of DNA, which the researchers named EFC#93, suggests early warning signs of life-threatening breast cancer.
These changes occur in patients’ blood before their cancer becomes detectable in their breast tissue.
A study revealed among women who have EFC#93 in their blood, 43 per cent were diagnosed with a life-threatening form of breast cancer three-to-six months later, while 25 per cent were diagnosed within six-to-12 months.
Study author Professor Martin Widschwendter from University College London, said: ‘For the first time, our study provides evidence that markers such as EFC#93 provide a highly specific indicator that could diagnose fatal breast cancers up to one year in advance of current diagnosis.’
‘This may enable individualised treatment, which could even begin in the absence of radiological evidence in the breast.’
There are around 55,000 new cases of breast cancer every year in the UK, with one in eight women being affected at some point in their lives.
How the research was carried out
The researchers analysed EFC#93 in blood samples from 419 breast cancer patients taken both after surgery but before chemotherapy and once chemotherapy was complete.
They demonstrated DNA change in samples taken before chemotherapy as a marker for poor prognosis even if cancer cells are not yet circulating in the body.
To assess whether EFC#93 can diagnose women with a poor prognosis earlier, the researchers then analysed samples of 925 healthy women, of which 229 went on to develop life-threatening breast cancer, while 231 got non-fatal forms of the disease within three years.
‘This may enable individualised treatment’
Professor Widschwendter said: ‘For the first time, our study provides evidence that markers such as EFC#93 provide a highly specific indicator that could diagnose fatal breast cancers up to one year in advance of current diagnosis.
‘This may enable individualised treatment, which could even begin in the absence of radiological evidence in the breast.
‘EFC#93 correctly identified 43 per cent of women tested six months in advance of their mammography-based breast cancer diagnosis who later died from the disease and also identified 88 per cent of women who did not go on to develop breast cancer.’
The accuracy of the test may also avoid unnecessary treatment in patients who would not otherwise have symptoms, according to the researchers.
Professor Widschwendter said: ‘Importantly, EFC#93 did not detect non-fatal breast cancers early. In comparison, mammography screening has a specificity of 88 to 92 per cent but leads to very substantial over-diagnosis, which means that tumours are detected that would never have caused any clinical symptoms.
‘Subject to further study, using cell-free DNA as a marker, as we have done here, is a promising way of avoiding this issue. ‘
The researchers add, however, blood samples must be processed immediately after they are drawn and stored in special tubes in order for the diagnosis to be accurate.
Future research should investigate whether women showing EFC#93 would benefit from treatment before the cancer itself becomes visible.
The findings were published in the journal Genome Medicine.
