Routine testing for bowel cancer should only be for men and women with a risk of 3% or more over the next 15 years, a study has found.
An evaluation of randomised trials, published in the BMJ, found that screening should not be recommended for everyone between 50 and 79 years due to low risk, small and uncertain benefit and potential harms.
Most guidelines currently recommend screening for everyone from the age of 50, no matter what their risk.
The study’s panel, made up of researchers, clinicians and patients, evaluated the benefit-to-harm balance in screening using a risk-based approach.
It looked at 15-year risk of bowel cancer alongside the risks of harm from the procedure, such as bowel perforations or unnecessary treatment, and quality of life.
The authors recommended using a scoring system to calculate risk, such as QCancer.
The evaluation said: ‘Overall there was substantial uncertainty (low certainty evidence) regarding the 15-year benefits, burdens and harms of screening. Best estimates suggested that all four screening options resulted in similar colorectal cancer mortality reductions.
‘A faecal immunochemical test every two years may have little or no effect on cancer incidence over 15 years, while FIT every year, sigmoidoscopy, and colonoscopy may reduce cancer incidence, although for FIT the incidence reduction is small compared with sigmoidoscopy and colonoscopy.’
It added: ‘Screening related serious gastrointestinal and cardiovascular adverse events are rare.’
The authors did not recommend one particular test and suggested that patients’ preferences over what test to have often varied considerably, so health professionals should use shared decision making when screening.
The study said: ‘Based on benefits, harms, and burdens of screening, the panel inferred that most informed individuals with a 15-year risk of colorectal cancer of 3% or higher are likely to choose screening, and most individuals with a risk of below 3% are likely to decline screening. Given varying values and preferences, optimal care will require shared decision making.’
Commenting on the research, Professor Philippe Autier, from the International Prevention Research Institute, said: ‘A risk-based approach is increasingly regarded as the most appropriate way to discuss cancer screening with individuals, and comprehensive guidelines for risk-informed decisions on prostate and lung cancer screening are available.
‘Fully informed decision making is destined to bring radical changes in the way cancer screening is introduced, as the priority is to ensure that eligible adults have received appropriate, balanced information on screening.’
It follows the news that only three in 10 women take up all cancer screening invitations, according to a study.
