NEW YORK (Reuters Health) - Patients with familial adenomatous polyposis (FAP) but without an identified adenomatous polyposis coli (APC) germline mutation have a unique severe phenotype characterized by a younger age at diagnosis and death, results of a new study suggest.
These characteristics “have to be taken into consideration” when counseling FAP families, Danish investigators write in the February issue of the journal Gut.
Dr. Marie Luise Bisgaard from Hvidovre University Hospital and colleagues compared the phenotypic traits in 218 FAP patients with and 52 without a known APC mutation from a total of 70 families.
Compared to FAP patients with an APC mutation, patients without an APC mutation tended to be younger when their first FAP symptoms appeared (31.2 vs 36.3 years) and died at an earlier age (39.6 vs 47.4 years), in spite of developing few colorectal adenomas.
They also had significantly fewer affected relatives (2.3 vs 4.6 per family) and were less likely to have involvement of the upper gastrointestinal tract or fundic gland polyposis and duodenal adenomas.
Commenting on the findings, Dr. Bisgaard said: “If DNA from such a patient is analyzed for mutations in the typical polyposis genes (APC and now also [the base excision repair gene] MYH) without identification of a mutation, it does not rule out polyposis and the patient as well as his/her close relatives should follow regular prophylactic examinations.”
“We have found that these patients actually have a more severe or aggressive form of polyposis, with earlier age at death, which could have been prevented if the patients had followed regular sigmoidoscopy, and consequently been operated before cancer development,” she continued.
Source: Gut 2004;53:266-270. [ Google search on this article ]
MeSH Headings:Digestive System Neoplasms: Gastrointestinal Neoplasms: Intestinal Neoplasms: Intestinal Polyps: Neoplasms: Neoplasms by Site: Genes, APC: DiseasesCopyright © 2002 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.
