Colon (tumor & nontumor)
MUTYH associated polyposis

Topic Completed: 1 August 2016

Minor changes: 31 July 2020

Copyright: 2002-2019,, Inc.

PubMed Search: MUTYH-associated polyposis

Raul S. Gonzalez, M.D.
Page views in 2019: 463
Page views in 2020 to date: 342
Cite this page: Gonzalez R. MUTYH associated polyposis. website. Accessed August 15th, 2020.
Definition / general
  • Autosomal recessive polyposis syndrome characterized by development of numerous colon adenomas, but usually fewer than in classic familial adenomatous polyposis
Essential features
  • Attenuated polyposis syndrome with biallelic MUTYH mutations and no FAP mutation
  • Increased risk for colorectal carcinoma
  • Outdated terms include "MYH-associated polyposis," "familial adenomatous polyposis 2" and "autosomal recessive adenomatous polyposis"
Clinical features
  • Mean age of diagnosis is about 50 years
  • Patients often have between 10 and 100 polyps (Int J Cancer 2004;109:680)
  • Biallelic mutations confer a 50 fold risk of colorectal carcinoma, and monoallelic mutation a 3 fold risk (Cancer Epidemiol Biomarkers Prev 2006;15:312)
  • Patients can also develop ovarian, bladder and breast carcinoma, as well as sebaceous gland tumors
  • Molecular testing to confirm biallelic MUTYH mutations
Case reports
Microscopic (histologic) description
  • Patients most commonly develop colonic tubular adenomas that resemble sporadic adenomas
  • Sessile serrated polyps can also occur
Microscopic (histologic) images

Contributed by Raul S. Gonzalez, M.D.

Adenoma associated with MUTYH mutation

Molecular / cytogenetics description
  • MUTYH is located at 1p34 and repairs oxidative DNA damage that otherwise can lead to carcinoma (Mod Pathol 2013;26:1371)
  • Most common mutations are Y165C and G382D
Differential diagnosis
Additional references
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