NHS cancer patients are being given extra fibre in a new study aimed at reducing the unpleasant side effects of radiotherapy and potentially increasing its effectiveness.
More than 200 men awaiting treatment for prostate cancer are being recruited from eight UK cancer centres for the trial, led by researchers from the University of Aberdeen’s Rowett Institute and the University of Manchester thanks to a £660,000 grant from Prostate Cancer UK.
Half the volunteers in the DIETRICH study will have their diet enriched with inulin (a fibre supplement derived from plants) before, during and after their treatment.
Inulin is a widely-available prebiotic that supports the growth of beneficial bacteria that reduce gut wall inflammation, which is a major cause of these side effects.
Researchers hope symptoms such as diarrhoea, bowel bleeding and bladder problems that occur when radiotherapy affects neighbouring non-cancerous cells can be made less severe or even eliminated.
The other half of the group will receive a dummy supplement with no active ingredient for the same period – starting two weeks before treatment and ending three weeks afterwards – and complete the same surveys and medical tests.
If the trial is successful - and the results then confirmed on a larger-scale - inulin supplements could become a routine part of treatment, meaning a more comfortable experience for patients and a reduction in the cost to the NHS of treating side effects.
Early studies in animals suggest fibre supplements may also boost radiotherapy’s ability to kill cancer cells, and the trial will further explore this potential.
Aberdeen’s Centre for Healthcare Randomised Trials (CHaRT) will handle the electronic collection of patient information using a specialised web-based data collection tool it has developed. As well as Aberdeen and Manchester, patients in Edinburgh, Glasgow, Liverpool, Preston, Leeds and Mount Vernon will take part.
Scotland and North West England are two of the regions with the highest proportion of men whose prostate cancer is diagnosed late, at stage four – one in three in Scotland and one in five in the north west.
Professor Anne Kiltie of the Rowett Institute, who is leading the study with University of Manchester’s Professor Ananya Choudhury, said: “We are delighted to receive funding from Prostate Cancer UK to undertake our study, DIETRICH. This study will test the value of inulin, a dietary fibre supplement with known health benefits, in men undergoing radiotherapy for prostate cancer. We anticipate that this will reduce intestinal and urinary side effects that men can experience from prostate radiotherapy and will allow us to confirm our laboratory findings. If our trial is successful, this will lead to us undertaking a much larger study on the benefits of inulin in men undergoing prostate radiotherapy.”
Dr Matthew Hobbs, Director of Research at Prostate Cancer UK, said: "For thousands of men with early-stage prostate cancer, radiotherapy is a highly effective and potentially curative treatment. Sadly, however, some men can experience debilitating side effects as a result of their radiotherapy, like bowel and urinary problems, which can significantly impact their quality of life.
"We’re really excited to be supporting this trial which is testing a relatively simple solution to tackle this significant problem. If shown to be effective, a fibre-rich diet could drastically reduce the severity of side effects that men experience as a result of their radiotherapy, resulting in faster recovery and a better quality of life. This study is being funded as part of a £2.7m investment from Prostate Cancer UK across 5 different projects to support innovative and ground-breaking research into the way we diagnose and treat prostate cancer.
"Prostate Cancer UK's is the UK's largest funder of prostate cancer research. Our schemes are deliberately designed to support different types of research and our Research Innovation Awards exist to support novel, game-changing projects just like this. It's particularly great to be funding ground-breaking research across Scotland and the North West, two regions where far too many men are being diagnosed with later-stage prostate cancer."
CHaRT director Professor Graeme MacLennan said: “We are excited to work with Profs Kiltie and Choudhury on this important clinical trial. Their lab work showed potential for inulin to reduce the nasty effects of prostate radiotherapy on the bladder and bowel. “The next step is to confirm these findings in men getting radiotherapy. We’ve helped design the trial, and now our job is to help deliver it!”
One person who is following the study closely is Dr Tim Ward, who own diagnosis with prostate cancer and the severe side effects he then experienced during radiotherapy forced him to take early retirement from his own job as a scientist researching cancer.
Dr Ward, who now acts as a patient advocate, said: “If the DIETRICH study had been available when I first started my radiotherapy, I would most certainly have signed up for it and hopefully my side effects would have been much less of an issue. I think it is now clear that modifying the gut bacteria is going to be important in future radiotherapy treatments.”