Mesenteric Fibromatosis : Genetics

Although some mesenteric fibromatosis lesions appear to be circumscribed grossly, they usually infiltrate microscopically into the surrounding tissues. Complete surgical removal is extremely difficult and accounts for frequent recurrences. Genetics: Tumors arising in the setting of FAP/Gardner syndrome carry inactivating mutations of the APC gene on chromosome 5q. Majority of the sporadic cases have mutations in CTNNB1 that codes for beta-catenin. These mutations result in nuclear accumulation of beta-catenin which can be detected immunohistochemically. Other genetic alterations that have been seen in fibromatoses include trisomy of chromosome 8 and 20 and loss of Y chromosome.