Familial adenomatous polyposis

Title

Other Names:

Adenomatous polyposis coli; FAP; Familial adenomatous polyposis of the colon; Adenomatous polyposis coli; FAP; Familial adenomatous polyposis of the colon; Familial polyposis of the colon; Polyposis, adenomatous intestinal; FPC; Adenomatous polyposis of the colon; Familial intestinal polyposis; Familial multiple polyposis; Hereditary polyposis coli; Familial polyposis coli See More

Categories:

Hereditary Cancer Syndromes; Rare Cancers

Subtypes:

Gardner syndrome

Summary Summary

Familial adenomatous polyposis (FAP) leads to the growth of hundreds to thousands of non-cancerous (benign) polyps in the colon and rectum. Overtime, the polyps can become cancerous (malignant), leading to colorectal cancer at an average age of 39 years. Symptoms of FAP may include dental abnormalities, tumors of the connective tissue (desmoid tumors), and benign and malignant tumors of the duodenum (a section of the small intestine), liver, bones, skin, and other tissues. Attenuated familial adenomatous polyposis (AFAP) is a milder form of FAP which includes fewer colon polyps (an average of 30). People with AFAP have an increased risk of developing colon cancer at a later age than classic FAP. FAP is due to genetic variants in the APC gene and is inherited in an autosomal dominant pattern. FAP is diagnosed based on the symptoms, clinical examination, and may be confirmed by the results of genetic testing. Management for FAP includes regular colon screening with endoscopy and other methods. Total removal of the colon (colectomy) is usually recommended to substantially reduce the risk for colon cancer. The recommended timing of surgery is based on multiple factors.^[1]^[2]^[3]^[4]

Last updated: 12/31/2020

Symptoms Symptoms

The following list includes the most common signs and symptoms in people with familial adenomatous polyposis (FAP). These features may be different from person to person, even within the same family. Some people may have more symptoms than others, and they can range from mild to severe. This list does not include every symptom that has been described in the condition.

Symptoms may include:^[1]^[2]^[3]

Hundreds to thousands of noncancerous growths (benign polyps) in the colon
Colon cancer
Polyps of the stomach
Adenomatous polyps of the small intestines
Benign bone tumors (osteomas)
Dental abnormalities
A pigmented spot within the outer layer of the retina (Congenital hypertrophy of the retinal pigment epithelium-CHRPE)
Benign skin abnormalities
Desmoid tumors
Other types of cancer (small bowel, stomach, pancreas, thyroid, central nervous system, liver, bile ducts, and/or adrenal gland)

Congenital hypertrophy of the retinal pigment epithelium (CHRPE) may be present at birth, but can only be seen with an eye exam. Colon polyps usually appear in the teens, and left untreated, most people with FAP will develop colon cancer by their late 30s or early 40s.

Last updated: 12/31/2020

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

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Medical Terms	Other Names	Learn More: HPO ID
80%-99% of people have these symptoms
Adenomatous colonic polyposis		0005227
Duodenal polyposis		0004783
Multiple gastric polyps		0004394
30%-79% of people have these symptoms
Colon cancer		0003003
5%-29% of people have these symptoms
Carious teeth	Dental cavities Tooth cavities Tooth decay [ more ]	0000670
Congenital hypertrophy of retinal pigment epithelium		0007649
Delayed eruption of teeth	Delayed eruption Delayed teeth eruption Delayed tooth eruption Eruption, delayed Late eruption of teeth Late tooth eruption [ more ]	0000684
Epidermoid cyst	Skin cyst	0200040
Fibroadenoma of the breast		0010619
Fibroma		0010614
Increased number of teeth	Extra teeth Increased tooth count Supplemental teeth [ more ]	0011069
Irregular hyperpigmentation		0007400
Multiple lipomas	Multiple fatty lumps	0001012
Neoplasm of the central nervous system	Tumors of the central nervous system	0100006
Odontoma		0011068
Osteoma		0100246
Unerupted tooth	Failure of eruption of tooth	0000706
1%-4% of people have these symptoms
Adrenocortical adenoma		0008256
Desmoid tumors		0100245
Duodenal adenocarcinoma		0006771
Hepatoblastoma		0002884
Medulloblastoma		0002885
Papillary thyroid carcinoma		0002895
Percent of people who have these symptoms is not available through HPO
Adrenocortical carcinoma		0006744
Astrocytoma		0009592
Autosomal dominant inheritance		0000006
Carcinoma		0030731
Hyperpigmentation of the skin	Patchy darkened skin	0000953
Keloids		0010562
Small intestine carcinoid		0006722
Variable expressivity		0003828

Showing of 31 |

Do you have more information about symptoms of this disease? We want to hear from you.

Last updated: 2/1/2021

Cause Cause

Familial adenomatous polyposis occurs when the APC gene is not working correctly. DNA changes known as pathogenic variants are responsible for making genes work incorrectly or sometimes, not at all.^[1]

Last updated: 12/31/2020

Inheritance Inheritance

Familial adenomatous polyposis is inherited in an autosomal dominant pattern.^[1] All individuals inherit two copies of each gene. Autosomal means the gene is found on one of the numbered chromosomes found in both sexes. Dominant means that only one altered copy of a gene is necessary to have the condition. The variant can be inherited from either parent. Sometimes an autosomal dominant condition occurs because of a new genetic variant (de novo), and there is no history of this condition in the family.

Each child of an individual with an autosomal dominant condition has a 50% or 1 in 2 chance of inheriting the variant and the condition. Typically, children who inherit a dominant variant will have the condition, but they may be more or less severely affected than their parent. Sometimes a person may have a gene variant for an autosomal dominant condition and show no signs or symptoms of the condition.

Last updated: 12/31/2020

Diagnosis Diagnosis

Familial adenomatous polyposis (FAP) is diagnosed based on the symptoms, clinical examination, and may be confirmed by the results of genetic testing. Imaging studies of the colon by endoscopy such as flexible sigmoidoscopy, colonoscopy, or other methods may also be helpful. Prenatal testing and genetic testing for at-risk relatives are possible if the disease-causing mutation in the family is known. Because colon screening for those at risk for classic FAP begins as early as age ten years, genetic testing is generally offered to children by this age. Testing may be offered earlier if the child is showing signs or symptoms of FAP.^[1]

The Genetic Testing Registry (GTR) is a centralized online resource for information about genetic tests. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

Last updated: 12/31/2020

Treatment Treatment

Treatment of familial adenomatous polyposis (FAP) is focused on managing the risk for colon cancer. Screening for colon cancer and polyps by endoscopy may begin in childhood. There is the option to remove the colon (colectomy) before colon cancer develops. The timing of this surgery is based on multiple factors. Guidelines for treatment and management of FAP and other polyposis conditions have been developed and published.^[4]^[5]

Specialists involved in the care of someone with familial adenomatous polyposis may include:

Medical geneticist
Gastroenterologist
Surgeon
Orthopedic surgeon
Ophthalmologist
Dentist

Last updated: 12/31/2020

Statistics Statistics

It has been estimated that between one in 7000 to one in 300,000 people is born with familial adenomatous polyposis.^[1]^[2]

Last updated: 12/31/2020

Do you have updated information on this disease? We want to hear from you.

Find a Specialist Find a Specialist

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

To find a medical professional who specializes in genetics, you can ask your doctor for a referral or you can search for one yourself. Online directories are provided by the American College of Medical Genetics and the National Society of Genetic Counselors. If you need additional help, contact a GARD Information Specialist. You can also learn more about genetic consultations from MedlinePlus Genetics.

Related Diseases Related Diseases

Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.

Conditions with similar signs and symptoms from Orphanet
Differential diagnoses include other disorders causing multiple polyps (Peutz-Jeghers syndrome, familial juvenile polyposis or hyperplastic polyposis, hereditary mixed polyposis syndrome, and Lynch syndrome; see these terms). Visit the Orphanet disease page for more information.

Research Research

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

ClinicalTrials.gov lists trials that are related to Familial adenomatous polyposis. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Patient Registry

A registry supports research by collecting of information about patients that share something in common, such as being diagnosed with Familial adenomatous polyposis. The type of data collected can vary from registry to registry and is based on the goals and purpose of that registry. Some registries collect contact information while others collect more detailed medical information. Learn more about registries.

Registries for Familial adenomatous polyposis:
DTRF Desmoid Tumor Patient Registry

Organizations Organizations

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

AMC Cancer Research Center
3401 Quebec St, Suite 3200
Denver, CO 80207
Toll-free: 800-321-1557
Telephone: 303-233-6501
Fax: 303-239-3400
E-mail: contactus@amc.org
Website: http://www.amc.org/
Colon Cancer Alliance
1025 Vermont Ave, NW
Suite 1066
Washington, DC 20005
Toll-free: (877) 422-2030 (Helpline)
Telephone: +1-202-628-0123 (Office)
Website: https://www.ccalliance.org/
Fight Colorectal Cancer
134 West Park Central Square
Suite 210
Springfield, MO 65806
Toll-free: 1-877-427-1211 (Helpline)
Telephone: +1-703-548-1225 (Office)
E-mail: Info@FightCRC.org
Website: https://fightcolorectalcancer.org/
IMPACC (Intestinal Multiple Polyposis and Colorectal Cancer)
P.O. Box 11
Conyngham, PA 18219
Telephone: 570-788-3712
Fax: 717-788-1818
The J-Pouch Group
Website: http://www.jpouch.org/

Organizations Providing General Support

American Cancer Society
250 Williams Street NW
Atlanta, GA 30329
Toll-free: 1-800-227-2345
Website: https://www.cancer.org
Cancer Hope Network
2 North Road, Suite A
Chester, NJ 07930
Toll-free: 1-877-467-3638 (1-877-HOPENET)
Telephone: +1-908-879-4039
Fax: +1-908-879-6518
E-mail: info@cancerhopenetwork.org/
Website: https://www.cancerhopenetwork.org/
Collaborative Group of the Americas on Inherited Gastrointestinal Cancer (CGA-IGC)
E-mail: https://www.cgaigc.com/contact
Website: http://www.cgaigc.com
Hereditary Colon Cancer Foundation
3519 NE 15th Avenue
Unit 518
Portland, OR 97212
Telephone: +1-334-740-8657
E-mail: info@HCCTakesGuts.org
Website: https://www.hcctakesguts.org/

Do you know of an organization? We want to hear from you.

Learn More Learn More

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

MedlinePlus Genetics contains information on Familial adenomatous polyposis. This website is maintained by the National Library of Medicine.
The Merck Manual provides information on this condition for patients and caregivers.
The National Cancer Institute provides the most current information on cancer for patients, health professionals, and the general public.
The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

In-Depth Information

GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
The Merck Manual for health care professionals provides information on Familial adenomatous polyposis.
The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine.
Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
PubMed is a searchable database of medical literature and lists journal articles that discuss Familial adenomatous polyposis. Click on the link to view a sample search on this topic.

GARD Answers GARD Answers

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.

Have a question? Contact a GARD Information Specialist.

References References

Jasperson KW, Patel SG, Ahnen DJ. APC-Associated Polyposis Conditions. GeneReviews. Updated Feb 2, 2017; http://www.ncbi.nlm.nih.gov/books/NBK1345/.
Dinarvand P, Davaro EP, Doan JV, Ising ME, Evans NR, Phillips NJ, Lai J, Guzman MA. Familial Adenomatous Polyposis Syndrome: An Update and Review of Extraintestinal Manifestations.. Arch Pathol Lab Med. Nov 2019; 143(11):1382-1398. https://pubmed.ncbi.nlm.nih.gov/31070935/.
Carr S, Kasi A.. Familial Adenomatous Polyposis. StatPearls. Nov 24, 2020; https://pubmed.ncbi.nlm.nih.gov/30855821/.
Provenzale D, Gupta S, Ahnen DJ, Bray T, Cannon JA, Cooper G, David DS, et al. Genetic/Familial High-Risk Assessment: Colorectal Version 1.2016, NCCN Clinical Practice Guidelines in Oncology. J Natl Compr Canc Netw. Aug 2016; 14(8):1010-30. https://pubmed.ncbi.nlm.nih.gov/27496117/.
Hyer W, Cohen S, Attard T, Vila-Miravet V, Pienar C, Auth M, Septer S, et al. Management of Familial Adenomatous Polyposis in Children and Adolescents: Position Paper From the ESPGHAN Polyposis Working Group. J Pediatr Gastroenterol Nutr. Mar 2019; 68(3):428-441. https://pubmed.ncbi.nlm.nih.gov/30585891/.