A blood test could soon predict who is most at risk of getting bowel cancer, potentially boosting survival chances.
Scientists have developed a new method which is more than 90 per cent accurate for detecting the disease in high-risk patients.
People with inflammatory bowel disease (IBD), such as Crohn’s and ulcerative colitis, are known to have more chance of developing bowel cancer.
Now doctors can predict which of these patients will develop bowel cancer in the next five years.
Experts hope this breakthrough will quickly lead to a blood test, improving early detection and reducing the need for invasive tests.
IBD can irritate the lining of the bowel and can cause abnormal pre-cancerous cells to form if left untreated.
In the study by the Institute of Cancer Research, working with doctors at St Mark’s, the UK’s specialist bowel hospital, samples of pre-cancerous cells were taken from 122 patients with IBD.
About half of the patients went on to develop bowel cancer within five years, whilst the other half remained cancer-free.
All of the samples had their full DNA scanned to look for changes in the structure and number of copies in the DNA.
Patients with IBD who developed bowel cancer were found to have lost multiple copies of their DNA, according to the findings published in the journal Gut.
The scientists also created an algorithm that calculates the risk of future bowel cancer, based on the exact pattern of the DNA which is altered in the pre-cancerous cells.
Used together, scientists hope the findings could spare people who are at much lower risk from the stress of needing regular colonoscopies or undergoing surgery to remove the colon.
Professor Trevor Graham, from the Institute of Cancer Research (ICR), which co-led the research, said: ‘Our test and algorithm give people with IBD, and the doctors who care for them, the best possible information so that they can make the right decision about how to manage their cancer risk.
‘We can accurately identify those people at high risk whilst putting the minds of many others at rest.’
Doctors are concerned about growing cases of bowel cancer cases among under-50s, with the UK having some of the highest increases in the last two decades.
While the exact reasons are unknown, poor diet and obesity are likely among the risk factors, which are also linked to rising cases of IBD.
It comes weeks after the NHS announced it was extending its bowel cancer screening to include over-50s.
The family of Dame Deborah James said she would be ‘grinning ear to ear’ about the decision which will make millions more eligible for the tests.
The mother-of-two who was diagnosed with incurable bowel cancer in 2016 and died aged 40 in 2022, fundraised for further research.
Dr Iain Foulkes, executive director of research and innovation at Cancer Research UK which funded this study, said: ‘With this research, we can focus resources on treating people with IBD who are at really high risk, saving health services valuable time and money.
‘We can also give those at lower risk peace of mind and remove the fear of bowel cancer in the future.’
