Tackling backlog in bowel screening

A BACKLOG of patients waiting for colonoscopies as part of the NHS bowel screening programme could be tackled by raising the threshold at which patients are invited for more in-depth investigations, according to new research.

Researchers at Queen Mary University of London investigated possible solutions to the current backlog caused by Covid-19 pressures and the gradual reduction in age at which people are invited for screening.

The NHS bowel screening programme uses two-yearly faecal immunochemical testing (FIT) to detect faecal blood in people aged 60-75. Those with levels above a f-Hb threshold of 120 μg/g are invited for a colonoscopy to look for potential signs of cancer needing treatment or further investigation.

Raising the blood test threshold to 180 μg/g could reduce the number of people invited for colonscopies from just over 16,000 to 11,500 for every 100,000 people screened over 15 years. The higher level threshold would mean 1077 cases of colorectal cancer (CRC) would be detected instead of 1142, with 131 CRCs prevented instead of 186, and 151 deaths prevented instead of 191.

The research (funded by the National Institute for Health and Care Research and published in the British Journal of Cancer) showed that increasing the threshold for the blood test would result in fewer lives being lost than increasing the time interval (to three years) between invitations (which would reduce required colonoscopies to 10,283 and prevent 126 CRCs).

Lead author and Professor of Cancer Screening at Queen Mary University of London, Stephen Duffy said: “There have been inevitable delays in screens as a result of the pandemic, but the NHS Bowel Cancer Screening Programme is recovering well. There are still pressures due to the age extension. If the programme must be adapted to cope with limited availability of colonoscopy, our results indicate that changing the FIT threshold may be the most useful option.”