October 2, 2019

expert reaction to paper advising against routine bowel cancer testing for all over 50s

A study, published in The BMJ, reports that the benefits of bowl cancer screening for 50-79 year olds with low risk are small and uncertain, and that there are potential harms. 

Dr Marco Gerlinger, Team Leader in Translational Oncogenomics at The Institute of Cancer Research, London, said:

“This new guideline recommends against bowel cancer screening for individuals with a bowel cancer risk below three per cent.

“Although the study takes into account the latest data on bowel cancer risk factors and screening effectiveness, the conclusion is based on the study authors’ own perception of how much discomfort and effort would be acceptable for a person before it outweighs the benefit of screening.  But it’s not clear whether the general population feels the same way – and it’s very likely that views on bowel cancer screening differ from person to person.

“Rather than working with a fixed cut-off, it would be better to discuss how someone’s personal risk weighs up against the benefit of bowel cancer screening once they reach screening age.  That way, people can make up their own mind about participating in a bowel cancer screening programme.

“Nevertheless, the study makes an important point: discussing someone’s personal risk and benefit could improve participation in screening programmes – particularly of people with high bowel cancer risk.  This would be an important step to reduce deaths from bowel cancer.”

Prof Anne Mackie, Director of Screening at PHE, said:

“This new report will be of much interest to the independent National Screening Committee.  The Committee already has work in development looking at how we can better use more personal information to help identify people and groups at greater risk of bowel cancer.  Taking a more targeted approach will help make screening more efficient, using up less resource, and more effective in finding more cancers earlier.”

Prof Stephen Duffy, Professor of Cancer Screening, Queen Mary University of London, said:

“I think the conclusion that we should move immediately to further risk stratification for bowel cancer screening is premature.  As the panel notes, we already screen based on the most important risk factor of all, age.  How much the other risk factors would add to this is unclear.  This also means that it is not certain what the total numbers of lives saved would be in the UK under the panel’s recommended regimen compared to the current bowel screening programme.

“While it is true that average risk of colorectal cancer is low at age 50, screening tends to prevent deaths not tomorrow but some years hence.  In recent decades, population mortality rates have fallen dramatically in middle to late age.  However, this is due to very small changes for any given disease, of the order of 1 per thousand per year or 0.5 per thousand per year.  Nevertheless, the small reductions in deaths from different causes all add up to a worthwhile prevention of premature mortality.”

‘Colorectal cancer screening with faecal immunochemical testing, sigmoidoscopy or colonoscopy: a clinical practice guideline’ by Lise M Helsingen et al. was published in the BMJ at 23:30 UK time on Wednesday 2 October 2019.

DOI: 10.1136/bmj.l5515

Declared interests

None received.