The Human Phenotype Ontology (HPO) provides the following list of features that have been reported in people with this condition. Much of the information in the HPO comes from Orphanet, a European rare disease database. If available, the list includes a rough estimate of how common a feature is (its frequency). Frequencies are based on a specific study and may not be representative of all studies. You can use the MedlinePlus Medical Dictionary for definitions of the terms below.
| Signs and Symptoms | Approximate number of patients (when available) |
| Adenomatous colonic polyposis | 90% |
| Intestinal polyposis | 90% |
| Duodenal polyposis | 50% |
| Neoplasm of the colon | 50% |
| Colon cancer | 33% |
| Multiple gastric polyps | 33% |
| Adrenocortical adenoma | 13% |
| Congenital hypertrophy of retinal pigment epithelium | 7.5% |
| Delayed eruption of teeth | 7.5% |
| Epidermoid cyst | 7.5% |
| Fibroadenoma of the breast | 7.5% |
| Increased number of teeth | 7.5% |
| Irregular hyperpigmentation | 7.5% |
| Multiple lipomas | 7.5% |
| Neoplasm of the nervous system | 7.5% |
| Odontogenic neoplasm | 7.5% |
| Osteoma | 7.5% |
| Sarcoma | 7.5% |
| Unerupted tooth | 7.5% |
| Hepatoblastoma | 1.6% |
| Medulloblastoma | 1% |
| Duodenal adenocarcinoma | % |
| Papillary thyroid carcinoma | % |
| Adrenocortical carcinoma | - |
| Astrocytoma | - |
| Autosomal dominant inheritance | - |
| Hyperpigmentation of the skin | - |
| Keloids | - |
| Odontoma | - |
| Small intestine carcinoid | - |
| Variable expressivity | - |
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.
Nonprofit support and advocacy groups bring together patients, families, medical professionals, and researchers. These groups often raise awareness, provide support, and develop patient-centered information. Many are the driving force behind research for better treatments and possible cures. They can direct people to research, resources, and services. Many groups also have experts who serve as medical advisors. Visit their website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD. Suggest an organization to add.
Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.
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.
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I had one colonoscopy with 24 adenomatous polyps and one polyp had cancer in it. I have since been diagnosed with attenuated familial adenomatous polyposis (AFAP). I am wondering when it is recommended to remove the colon. See answer
What is the recommended follow up or management of AFAP after the colon has been removed? The small intestine is connected to the rectum. I have had polyps in the rectum and also in the stomach since the colon was removed. How often do I need to do follow up tests to make sure nothing is growing in there? See answer
