Ireland
--:--IST
Recruiting Observational

Microbial and Environmental Factors Associated With Polyps Development in Familial Adenomatous Polyposis (MicrobEnvironment in FAP)

NCT06614738 · tracked via the Priya Life Science France tracker
Phase
Observational
Started
2024-12-17
Last updated
2026-05-27

Condition(s) studied

Familial Adenomatous Polyposis

Investigational drug(s) / intervention(s)

Sampling of feces and duodenal fluids

Sampling of feces and duodenal fluids: * Blood sampling (plasmotheque and serotheque): 2 tubes (EDTA (5mL) and dry (5mL)) during hospitalization * Fecal sampling (fecal library): A stool sample (approx. 2g) will be taken 48 hours before the endoscopy at home for outpatient or during hospitalization * Duodenal aspiration fluid (6-10 mL in total): before and after mucosal lavage with sterile isotonic saline on the day of endoscopy. * Food and Lifestyle Questionnaire (FFQ) during inclusion

Study summary

Familial adenomatous polyposis (FAP) is an autosomal dominant inherited disorder linked to a mutation in the APC gene, associated with the development of multiple colonic and duodenal adenomas, which in 100% of cases progress to colorectal cancer (CRC) if left untreated. Management of affected patients is usually based on prophylactic total colectomy with or without rectal preservation, followed by regular endoscopic surveillance of the duodenum and rectum or ileal reservoir. However, there is considerable inter- and intra-familial variability in the rate of adenoma appearance and development for identical mutations. This strongly suggests the additional role of environmental factors. Recently, the gut microbiota has been identified as a co-factor of carcinogenesis in patients with FAP, but no prospective evaluation of the association between the incidence and severity of adenomatous proliferations and a microbiological signature has been studied, particularly at duodenal level in operated patient.

Eligibility

Sex
ALL
Min age
18 Years
Max age
—
Healthy volunteers
No
Inclusion Criteria: * ≥18 years * Non-opposition obtained * Prophylactic colectomy for at least 2 years in the context of APC-related familial adenomatous polyposis with ileorectal or ileoanal anastomosis * Included in the national POLYPOSE database * Regular endoscopic follow-up with upper and lower GI endoscopy at Hôpital Edouard Herriot or Hôpital de la Croix-Rousse * Having performed at least 2 endoscopies as part of follow-up Exclusion Criteria: * Antibiotic therapy within 2 months prior to stool sampling * Taking probiotics for less than 1 month * Person deprived of liberty by judicial or administrative decision

Primary outcome measure(s)

  • Fecal microbiota composition — Within 48 hours of endoscopy
    Analysis of fecal microbiota composition as a function of the cumulative number of reservoir (rectum or ileal) adenomas treated over 3 consecutive endoscopies

Trial sites (2)

FacilityCityRegionStatus
Hôpital Edouard Herriot Lyon France Recruiting
Hôpital de la Croix Rousse Lyon France Recruiting
Official registry record

This page summarises publicly available registry data for informational purposes — not medical advice. Eligibility is determined by each study team; patients should discuss participation with their clinician.

View NCT06614738 on ClinicalTrials.gov ↗ ← All trials in France