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Familial adenomatous polyposis classification

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Sadaf Sharfaei M.D.[2], Mohamad Alkateb, MBBCh [3]

Overview

Overview

Familial adenomatous polyposis (FAP) may be classified according to the affected gene into two subtypes including FAP gene and MYH gene associated familial adenomatous polyposis. Familial adenomatous polyposis may be classified according to severity into three subtypes including profuse, intermediate, and attenuated. Familial adenomatous polyposis has less severe variants, including gardner’s syndrome and turcot syndrome.

Classification

Classification

Familial adenomatous polyposis may be classified according to the affected genes into two subtypes:[1][2]

  • FAP gene associated familial adenomatous polyposis
  • MUTYH-associated polyposis (MAP)

Familial adenomatous polyposis may also be classified according to severity into three subtypes:[3]

  • Profuse FAP
  • Intermediate FAP
  • Attenuated FAP
Type Characteristics Age of onset for polyp Age of onset for cancer
Profuse Thousands of polyps 15-20 35-40
Intermediate Hundreds to thousands of polyps 25-30 45-50
Attenuated Less than 100 polyps 35-40 55-60

Variants

Familial adenomatous polyposis has less severe variants, including:

References

References

  1. Iaquinto, Gaetano; Fornasarig, Mara; Quaia, Michele; Giardullo, Nicola; D’Onofrio, Vittorio; Iaquinto, Salvatore; Di Bella, Simone; Cannizzaro, Renato (2008). “Capsule endoscopy is useful and safe for small-bowel surveillance in familial adenomatous polyposis”. Gastrointestinal Endoscopy. 67 (1): 61–67. doi:10.1016/j.gie.2007.07.048. ISSN 0016-5107.
  2. King, John E.; Dozois, Roger R.; Lindor, Noralane M.; Ahlquist, David A. (2000). “Care of Patients and Their Families With Familial Adenomatous Polyposis”. Mayo Clinic Proceedings. 75 (1): 57–67. doi:10.4065/75.1.57. ISSN 0025-6196.
  3. Nieuwenhuis, M.H.; Vasen, H.F.A. (2007). “Correlations between mutation site in APC and phenotype of familial adenomatous polyposis (FAP): A review of the literature”. Critical Reviews in Oncology/Hematology. 61 (2): 153–161. doi:10.1016/j.critrevonc.2006.07.004. ISSN 1040-8428.

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