Evaluation of the ileo-anal pouch in FAP (ENDOPOL)
Research type
Research Study
Full title
ENDOPOL: dye chromoENDOscopy versus virtual chromoendoscopy for assessment of the ileo-anal pouch in patients with familial adenomatous POLyposis: a randomized controlled trial
IRAS ID
365649
Contact name
Andrew Latchford
Contact email
Sponsor organisation
London North West University Healthcare NHS Trust
Duration of Study in the UK
4 years, 11 months, 31 days
Research summary
Familial adenomatous polyposis (FAP) is a rare inherited condition that causes hundreds to thousands of polyps (small growths) to develop in the colon and rectum. If left untreated, almost all individuals with FAP will develop bowel cancer, typically between ages 35 and 45. To prevent cancer, most patients have surgery to remove the colon, and sometimes the rectum. In many cases, a new internal pouch is created from the small intestine and connected to the anus, allowing the patient to pass stool normally.
Even after surgery, patients with FAP remain at risk of developing new polyps in the remaining rectum or the pouch. Over time, up to 75% of patients with a pouch will develop these growths, and about 1–2% may go on to develop cancer. This highlights the need for regular endoscopic check-ups (pouchoscopy), during which sizeable polyps found are removed.
Current European guidelines recommend a pouchoscopy every 1–2 years, removing polyps larger than 5mm. However, it’s not clear which imaging technique works best for spotting these growths. Standard tools like white-light endoscopy (WLE), narrow-band imaging (NBI), and blue laser imaging (BLI) are commonly used. Some specialized centres, however, use dye-based chromoendoscopy, which may highlight flat or hidden polyps more effectively.
Early research suggests dye-based methods may detect more polyps, including some that are larger or potentially more dangerous. However, these techniques are more time-consuming and not widely used. There is also limited data comparing dye-based techniques to the newer “virtual” chromoendoscopy methods like NBI or BLI.
This project aims to determine which technique is best at detecting significant polyps in FAP patients. Improving detection may help prevent cancer and reduce the need for additional surgery to remove the pouch.
REC name
East Midlands - Nottingham 2 Research Ethics Committee
REC reference
26/EM/0070
Date of REC Opinion
9 Apr 2026
REC opinion
Further Information Favourable Opinion