Identifying the need for a UK colorectal cancer screening programme for patients with cystic fibrosis (CF): 10-year retrospective review of colonoscopy and colorectal cancer outcomes at a single CF centre.

Objective: Patients with cystic fibrosis (pwCF) have a high incidence of early colorectal cancer (CRC). In the absence of a UK CRC screening programme for pwCF, we evaluated the utility and outcomes of colonoscopy and CRC at a large UK CF centre.

Design: In a retrospective study of colonoscopy and CRC outcomes between 2010 and 2020 in pwCF aged≥30 years at a large CF centre, data were collected on colonoscopy indications and findings, polyp detection rates, bowel preparation regimens and outcomes, colonoscopy completion rates, and patient outcomes.

Results: We identified 361 pwCF aged ≥30 years, of whom 135 were ≥40 years old. In the absence of a UK CRC screening guideline only 33 (9%)/361 pwCF aged ≥30 years (mean age: 44.8±11.0 years) had a colonoscopy between 2010 and 2020. Colonoscopy completion rate was 94.9%, with a 33% polyp detection rate, 93.8% of the polyps retrieved were premalignant. During the study period no patients developed postcolonoscopy CRC. However, of the patients aged ≥40 years who did not have a colonoscopy (111/135, 82.2%), four (3.6%) patients developed CRC and three pwCF died from complications of CRC.

Conclusion: In this 10-year experience from a large CF centre, colonoscopy uptake for symptomatic indications was low, yet of high yield for premalignant lesions in pwCF >40 years. These data highlight the risk of potentially preventable, early CRC, and therefore support the need for prospective, large-scale nationwide studies which may inform the need for UK CRC screening guidelines for pwCF.