The influence of mutation site and age on the severity of duodenal polyposis in patients with familial adenomatous polyposis.
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.
Saurin
Jean-Christophe
JC
Fédération des spécialités digestives, Laboratoire de génétique, Hôpital E. Herriot, 5 place d'Arsonval, 64937 Lyon Cedex 03, France.
Ligneau
Blandine
B
Ponchon
Thierry
T
Leprêtre
Jean
J
Chavaillon
Annick
A
Napoléon
Bertrand
B
Chayvialle
Jean-Alain
JA
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
D003062:Codon