Colon tumor
Hereditary mixed polyposis syndrome

Topic Completed: 1 July 2016

Minor changes: 21 June 2019

Copyright: 2002-2019,, Inc.

PubMed Search: Hereditary mixed polyposis syndrome

Raul S. Gonzalez, M.D.
Page views in 2019: 224
Page views in 2020 to date: 93
Cite this page: Gonzalez R. Hereditary mixed polyposis syndrome. website. Accessed June 3rd, 2020.
Definition / general
  • Rare, autosomal dominant syndrome causing patients to develop numerous types of polyps throughout the colon (OMIM #01228)
  • Patients generally develop 15 or fewer polyps
Essential features
  • Rare colonic polyposis syndrome with several possible causative mutations
  • Occurs in Ashkenazi Jewish patients and may lead to colorectal carcinoma
  • Previously called "mixed familial polyposis"
Clinical features
  • Mean age of presentation is 41 years
  • Increased risk of developing colorectal carcinoma (Nat Genet 2008;40:623)
  • No known extra-colonic manifestations
Microscopic (histologic) description
  • Polyps of mixed histologic types (tubular adenomas, villous adenomas, flat adenomas, hyperplastic polyps, atypical juvenile polyps)
  • Most polyps are adenomas
Molecular / cytogenetics description
Differential diagnosis
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