AFAP
Research type
Research Study
Full title
Attenuated familial adenomatous polyposis - clinical outcomes and assessment of familial variability?
IRAS ID
253340
Contact name
CHUKWUEMEKA ANELE
Contact email
Sponsor organisation
London North West University Healthcare NHS Trust
Duration of Study in the UK
3 years, 0 months, 1 days
Research summary
Familial adenomatous polyposis is a hereditary condition that predisposes to colorectal cancer (CRC). Patients with FAP characteristically develop hundreds to thousands of colorectal polyps in adolescence or by the third decade of life. If left untreated, progression to CRC is almost inevitable. The risk of CRC is normally considered to be related to the number and size of the polyps. FAP is caused by mutation in the adenomatous polyposis coli (APC) gene and the severity of the disease is based on the location of mutation on the APC gene (genotype-phenotype correlation).
Mutations in three regions of the APC gene are associated with a milder course of gastrointestinal disease (fewer than 100 colorectal adenomas and later onset of colorectal adenomas) and are described as attenuated FAP (AFAP)). However, attenuated FAP remains a poorly understood disease due to its widely observed variability. Some patients with mutations in these three attenuated regions have been found to have severe disease. This poses a diagnostic and surveillance challenge. In this study, we aim to evaluate: (1) correlation between mutation in the 3 regions and the severity of disease in patients with presumed AFAP and (2) variability in severity of disease between first-degree relatives with AFAP and families with similar mutation.
Individuals with AFAP will be identified from our registry. Attenuated FAP will be defined as colorectal adenomas <100 at age 25 years and patients with mutation in 3 APC regions thought to be associated with AFAP. Pathology colorectal polyp count (PPC) will be used for patients who had undergone surgery and endoscopic colorectal polyp count (EPC) for those who haven’t had surgery.
REC name
North West - Preston Research Ethics Committee
REC reference
18/NW/0664
Date of REC Opinion
25 Sep 2018
REC opinion
Favourable Opinion