APC mosaicism in a young woman with desmoid type fibromatosis and familial adenomatous polyposis.

Content Provider	Europe PMC
Author	Stormorken, Astrid Tenden Berg, Thomas Norum, Ole-Jacob Hølmebakk, Toto Aaberg, Kristin Steigen, Sonja E. Grindedal, Eli Marie
Abstract	Familial adenomatous polyposis (FAP) is usually caused by germline mutations in the adenomatous polyposis coli (APC) gene. The classic form is characterized by hundreds to thousands of adenomas in the colorectum and early onset colorectal cancer (CRC) if left untreated. FAP is also associated with multiple extra-colonic manifestations such as gastroduodenal polyps, osteomas, epidermoid cysts, fibromas and desmoids. Most desmoid tumours in FAP patients occur intra-abdominally. Approximately 15–20% of the APC mutations are de novo mutations. Somatic mosaicism has been reported in some sporadic cases of polyposis but is probably an underestimated cause of the disease. This case report presents the detection of a mosaic APC mutation in a 26-year-old woman who as a child had been diagnosed with desmoid type fibromatosis. FAP was suggested when she presented with extensive extra abdominal fibromatosis. Our findings indicate that APC mutations may be suspected in patients presenting with a desmoid regardless of its location. If there is clinical evidence that the patient has FAP, adenomas and colonic mucosa in addition to leukocyte DNA should be included in the screening, preferably using methods that are more sensitive than Sanger sequencing.
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ISSN	13899600
Journal	Familial Cancer [Fam Cancer]
Volume Number	17
DOI	10.1007/s10689-018-0072-8
PubMed Central reference number	PMC6182574
Issue Number	4
PubMed reference number	29368261
e-ISSN	15737292
Language	English
Publisher	Springer Netherlands
Publisher Date	2018-10-01
Publisher Place	Dordrecht
Access Restriction	Open
Rights License	Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. © The Author(s) 2018
Subject Keyword	Desmoid type fibromatosis Familial adenomatous polyposis APC gene Mosaicism Desmoids
Content Type	Text
Resource Type	Article
Subject	Genetics Cancer Research Genetics (clinical) Oncology