Scientists have made an important step in the study of how bowel cancer develops which could help put a stop to over-diagnosis and save the NHS millions in future.
Due to the national bowel screening programme, tens of thousands of people a year in the UK are found to have adenomas, or polyps, in the bowel which can be a precursor to cancer.
These patients then have an endoscopy where the adenoma is removed. Usually they are then considered to be at risk of developing cancer in future and are therefore subject to regular screening for the rest of their lives.
However, most adenomas are benign and the patient is unlikely to ever develop bowel cancer so much of the follow-up screening is likely to be unnecessary.
Researchers, funded by the charity Bowel & Cancer Research, have made the first steps in predicting which adenomas, or polyps, in the bowel become cancerous and why.
They are now trying to develop a simple test which would signal the end of unnecessary follow-up screening.
"While the bowel cancer screening programme has been very successful at reducing the number of deaths from bowel cancer, it also inadvertently leads to the detection of many benign colorectal adenomas," said lead researcher Dr Trevor Graham from Queen Mary University of London's Barts Cancer Institute in London.
"These are not themselves dangerous but are interpreted as a sign that the patient has an increased risk of future cancer development. It means that many people are being over-diagnosed as having an increased risk of bowel cancer when in reality they are not at risk at all.
"They then receive regular intensive surveillance for the rest of their lives which is probably unnecessary in many cases.
"If we can identify which adenomas are most likely to become cancerous, it will save a huge amount of resources and prevent unnecessary treatment."
His team has compared the genetic make-up of benign adenomas with those that become cancerous and discovered that the cells of malignant adenomas are more genetically diverse and evolve more quickly.
The next step is to develop a simple test to show how genetically diverse a tumour is, and show that it predicts which parents are at high risk of developing cancer in future.
"Previously, to try and distinguish a benign adenoma from a potentially malignant one the approach has been to simply look at the adenoma under a microscope. Our approach is fundamentally different - we measure how a tumour is evolving over time," said Dr Graham.
"Developing a successful test for cancer risk will mean that clinical resources can be focused only on those people who need it and low-risk people can be spared unnecessary and unpleasant treatment and expensive follow-up care."
The research has been headed up by Dr Trevor Graham at Barts Cancer Institute, part or Queen Mary University of London, together with his Oxford University colleague Dr Simon Leedham.
It has led to further funding from Cancer Research UK, and from the Barts Charity, together worth almost £1.5 million.
Dr Graham said that funding from Bowel & Cancer Research had been "absolutely critical" to the success of their work.
Chief Executive of the charity, Deborah Gilbert, said: "Bowel & Cancer Research can invest in research only because of the generosity of its many supporters, most of whom have been touched in some way by bowel cancer. For them, their families and friends, I am delighted that the charity has played such a fundamental role in this research which has the potential to benefit many thousands of people in the future."
More than 40,000 people per year in the UK are diagnosed with bowel cancer every year and the disease claims more than 16,000 lives.