title: The influence of mutation site and age on the severity of duodenal polyposis in patients with familial adenomatous polyposis.
abstract: BACKGROUND
  The present study was undertaken to identify factors affecting the severity of the duodenojejunal polyposis in patients with familial adenomatous polyposis.
  
  
  METHODS
  Duodenojejunal polyposis was evaluated in 41 consecutive patients with familial adenomatous polyposis (mean age 41 years, range 21-63 years), 33 (80%) with known APC mutation, by using a standardized endoscopic protocol. The severity of the polyposis was graded with the Spigelman scoring system (0-12 points), the Spigelman score/age ratio, and the presence or absence of advanced adenomas (>1 cm in diameter and/or high-grade dysplasia).
  
  
  RESULTS
  The Spigelman score (median 8, range 3-12) was higher in patients older than 50 years (median 10, range 3-12) as compared with younger patients (median 7.5, range 3-11; p = 0.043). A significant association between age and the presence of advanced adenomas was also observed. Patients with a mutation in the central part of the APC gene (codons 279-1309) had a higher Spigelman score and Spigelman score/age ratio as compared with patients with other mutations: median Spigelman score/age ratio 0.21 (range 0.14-0.40) versus 0.10 (range 0.06-0.20) (p < 0.001).
  
  
  CONCLUSIONS
  Older age and APC mutation in the central part of the gene are risk factors for the development of severe duodenojejunal polyposis.
authors.affiliation: Fédération des spécialités digestives, Laboratoire de génétique, Hôpital E. Herriot, 5 place d'Arsonval, 64937 Lyon Cedex 03, France.
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Saurin
authors.forename: Blandine
authors.initials: B
authors.lastname: Ligneau
authors.forename: Thierry
authors.initials: T
authors.lastname: Ponchon
authors.forename: Jean
authors.initials: J
authors.lastname: Leprêtre
authors.forename: Annick
authors.initials: A
authors.lastname: Chavaillon
authors.forename: Bertrand
authors.initials: B
authors.lastname: Napoléon
authors.forename: Jean-Alain
authors.initials: JA
authors.lastname: Chayvialle
mesh_terms: D011125:Adenomatous Polyposis Coli / Q000145:classification / Q000235:genetics* / Q000473:pathology; D000328:Adult; D000367:Age Factors; D003062:Codon; D004379:Duodenal Neoplasms / Q000145:classification / Q000235:genetics* / Q000473:pathology; D016099:Endoscopy, Gastrointestinal; D005260:Female; D017353:Gene Deletion; D017491:Genes, APC; D006801:Humans; D007580:Jejunal Neoplasms / Q000145:classification / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009154:Mutation; D012720:Severity of Illness Index
chemical_list: D003062:Codon