Familial adenomatous polyposis in pediatrics: natural history, emerging surveillance and management protocols, chemopreventive strategies, and areas of ongoing debate

Abstract

Familial adenomatous polyposis (FAP) is a hereditary condition with a near 100 % lifetime risk of colorectal cancer without prophylactic colectomy. Most patients with FAP have a mutation in the adenomatous polyposis coli gene on chromosome 5q22. This condition frequently presents in children with polyps developing most frequently in the second decade of life and surveillance colonoscopy is required starting at age ten. Polyps are found not only in the colon, but in the stomach and duodenum. Knowledge of the natural history of FAP is important as there are several extra-colonic sequelae which also require surveillance. In infants and toddlers, there is an increased risk of hepatoblastoma, while in teenagers and adults duodenal carcinomas, desmoid tumors, thyroid cancer and medulloblastoma are more common in FAP than in the general population. Current chemopreventive strategies include several medications and natural products, although to this point there is no consensus on the most efficacious and safe agent. Genetic counseling is an important part of the diagnostic process for FAP. Appropriate use and interpretation of genetic testing is best accomplished with genetic counselor involvement as many families also have concerns regarding future insurability or discrimination when faced with genetic testing.

Hepatoblastoma in patients with molecularly proven familial adenomatous polyposis: Clinical characteristics and rationale for surveillance screening

“…reported four (2.5%) with hepatoblastoma out of 163 patients with FAP reviewed . This has led to various recommendations of screening for hepatoblastoma in patients with known FAP . The variety of published screening recommendations include frequency of testing (from every 2–3 months to every 12 months), tests to be utilized (AFP and abdominal US, or one or the other of these two), and age at which testing should be undertaken (from birth or infancy to < 10 years of age).…”

WEO Newsletter

“…For example, for familial adenomatous polyposis (FAP), endoscopology should consider its hereditary nature, its natural history, emerging surveillance and management protocols, and chemopreventive strategies . It is a hereditary condition with a nearly 100% lifetime risk of colorectal cancer unless prophylactic colectomy is done.…”

Clinically Relevant Anti-Inflammatory Agents for Chemoprevention of Colorectal Cancer: New Perspectives

“…There will be ample opportunity to intervene at the precursor/adenoma stage thereby preventing the progression into invasive carcinoma by screening and chemopreventive interventions [18,19,20]. Due to existing technologies and significant advances in the early detection of CRC by colonoscopy or identifying high risk population at forefront is driving the science towards developing appropriate chemoprevention strategies [18,19]. …”