Colon tumor
Familial polyposis syndromes
Hereditary mixed polyposis syndrome

Author: Raul S. Gonzalez, M.D. (see Authors page)

Revised: 14 July 2016, last major update July 2016

Copyright: (c) 2002-2016,, Inc.

PubMed Search: Hereditary mixed polyposis syndrome

Cite this page: Hereditary mixed polyposis syndrome. website. Accessed December 11th, 2018.
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