Familial Adenomatous Polyposis [FAP] (20) Flashcards
What is FAP?
Familial Adenomatous Polyposis is an Autosomal dominant condition characterized by loss of APC tumor suppressor gene on the long arm of chromosome 5 leading to development of hundreds of tubular adenomas with 100% risk of cancer by the age of 40.
What are the functions of the APC tumor suppressor gene?
Encodes a factor that negatively regulates the WNT pathway in colonic epithelium by promoting the formation of a complex that degrades β-catenin.
What are the classifications of polyps?
- Non-neoplastic:
- Hamartomatous
- Metaplastic
- Inflammatory:
- Pseudopolyps
- Ulcerative colitis
- Neoplastic:
- Villous (40%)
- Tubulovillous (20%)
- Tubular (5%)
What are the extracolonic manifestations in the related gardener syndrome?
- Mandibular osteoma
- Desmoid tumors
- Sebaceous cyst
What does the malignant potential of adenomas depend on?
- Type of adenoma
- Diameter of adenoma:
- < 1 cm → 5%
- 2 cm → 20%
- Degree of dysplasia
What is the management for FAP?
Prophylactic near total colectomy by the age of 25.
What is the advice for a patient with a 2-year-old child?
Colonoscopic screening by the age of 12.
What is dysplasia?
- Disordered cellular development characterized by increased mitosis, pleomorphism without the ability to invade the basement membrane.
- Severe dysplasia = carcinoma in situ.
What is endometriosis?
Defined by the presence of “ectopic” endometrial tissue at a site outside of the uterus.
What is pus?
A collection of neutrophils plus dead or dying microorganisms.
What is an abscess?
A collection of pus surrounded by granulation or fibrous tissue.
What is an ulcer?
A lesion in the mucous membrane or the skin resulting from the gradual disintegration of surface epithelial cells.
What is secondary intention?
Secondary healing by re-epithelialization and contraction.
What are the lifestyle modifications to reduce the risk of colon cancer?
- Fibre-rich diet
- Limit alcohol
- Reduce fat intake
- Stop smoking.
