Duodenal involvement in MUTYH-associated polyposis: findings from an international study and implications for endoscopic surveillance.
Measured against the standard of care· ACG 2026 (adenomatous polyposis: Mankaney et al., Am J Gastroenterol 2026;121:2086-2120) / ACG 2015 (Lynch, SPS: Syngal et al.)
Decision at stakethe timing and scope of duodenal surveillance in MUTYH-associated polyposis
… For FAP, AFAP and MAP, upper endoscopic surveillance that includes viewing the duodenal papilla is suggested over no surveillance (Recommendation 8, conditional). … Lynch syndrome and serrated polyposis syndrome are outside the 2026 document, so the Lynch and SPS parts of the standard on file were not re-verified here: Lynch colonoscopy every 1-2 years from age 20-25, gyn and upper-GI surveillance, and SPS colonoscopy every 1-3 years with removal of polyps over 5 mm.
From our summary of this standard, unedited — the part the paper bears on. … marks omitted text. Our wording, not the guideline's; read the source for its own text.
Our full summary of this standard
Polyposis syndromes are now governed by ACG 2026 (Mankaney G, Idos GE, Stoffel EM, Weiss JM, Shah S, Qayed E, Harnegie MP, Burke CA; Am J Gastroenterol 2026;121(9):2086-2120, GRADE). For polyposis, it replaces the 2015 ACG hereditary GI cancer guideline (Syngal et al.), Recommendations 10-11. Germline multigene panel testing is recommended for anyone with 20 or more cumulative lifetime colorectal adenomas (strong recommendation) and suggested for 10-19 adenomas (conditional, because the yield is lower). The 2015 polyposis testing trigger was more than 10 adenomas. Asymptomatic APC carriers, biallelic MUTYH carriers, and untested people at risk for AFAP or MAP should have a baseline colonoscopy by age 18-20. Colonoscopy then repeats every 1-3 years depending on the histology, size and number of polyps. It moves to every 3-6 months when there are many or large polyps, or high-grade dysplasia. This replaces the 2015 schedules of annual sigmoidoscopy/colonoscopy from puberty for classic FAP, colonoscopy every 1-2 years from the late teens for AFAP, and from age 25-30 for MAP. Whether at-risk children in classic-FAP families still start younger is not stated in the excerpt available at review; confirm against the full text. For FAP, AFAP and MAP, upper endoscopic surveillance that includes viewing the duodenal papilla is suggested over no surveillance (Recommendation 8, conditional). Duodenal management is still staged by Spigelman, which has acknowledged limits in sensitivity for duodenal and papillary cancer. The 2026 starting age and intervals for upper endoscopy are not stated in the excerpt available at review. The choice of operation (total colectomy with IRA, IPAA, or end ileostomy) is individualized by genotype, polyp distribution, cancer status, comorbidity and preference, with early referral to an experienced colorectal surgeon. IRA is generally favored with up to about 20 rectal adenomas and IPAA above that, though this is not a fixed cutoff. The rectum or pouch should be checked endoscopically every year after IRA or IPAA. Chemoprevention is recommended against as a substitute for colectomy when surgery is indicated. Whether 2026 keeps annual thyroid ultrasound is not stated in the excerpt available at review. Lynch syndrome and serrated polyposis syndrome are outside the 2026 document, so the Lynch and SPS parts of the standard on file were not re-verified here: Lynch colonoscopy every 1-2 years from age 20-25, gyn and upper-GI surveillance, and SPS colonoscopy every 1-3 years with removal of polyps over 5 mm.