Symptoms are uncommon until the adenomas are large and numerous causing hematochezia or anemia. Other non-specific complaints such as change in bowel habits, constipation, diarrhea and abdominal pain may occur.

75 to 80% of affected individuals have a family history of polyps or colorectal cancer at age 40 years or younger. Patients can also develop a variety of extracolonic manifestations.

• Pain

  A 38-year-old lady presented with abdominal pain, diarrhoea and iron deficiency anemia. There was no history of colorectal cancer in the family. [ncbi.nlm.nih.gov]

  Gastric polyps may cause epigastric pain or bleeding. Duodenal polyps may cause pain, bleeding or obstructive jaundice. Polyps in the ileum may cause obstruction. [patient.info]

  Signs and symptoms of FAP and colorectal cancer include: Blood or mucus in the stool Rectal bleeding Rectal pain Diarrhea Constipation Abdominal pain Weight loss Risks Causes and Risk Factors of Familial Adenomatous Polyposis The primary risk factor for [loyolamedicine.org]

  […] to manage the pain and inflammation. are well documented to reduce adenoma numbers in FAP, and all CRCs in FAP arise from adenomas. [wiki.cancer.org.au]

• Weight Loss

  In the event of malignancy, an individual may experience weight loss, persistent unexplained fatigue, altered bowel movement and, if the tumours are not treated in time, cancer metastasis to areas such as the liver. [genomicseducation.hee.nhs.uk]

  There were no patients with a body weight loss of ≥10 % relative to the preoperative body weight. No recurrence were experienced during the follow up period. Patients were free from postoperative diabetes mellitus. [ncbi.nlm.nih.gov]

  Common symptoms of polyp formation and colorectal cancer are: rectal bleeding tummy pain bony growths common cancer-related symptoms such as unexplained weight loss and fatigue. [yourgenome.org]

• Thyroid Nodule

  A large fetal liver mass was detected on routine ultrasound examination of a 23-year-old woman with thyroid nodules and hypertension. Inferior vena cava compression prompted delivery; postnatal biopsy revealed hepatoblastoma. [ncbi.nlm.nih.gov]

  Annual thyroid exam and thyroid ultrasound beginning in the late teenage years. The thyroid ultrasound is better at detecting small thyroid nodules that might be missed by a physical examination alone. [chop.edu]

• Aspiration

  If there is any change in size or other ultrasonographic features of any of these nodules, we would evaluate further with another fine needle aspiration biopsy. [healio.com]

  Colonoscopy revealed large bowel polyposis and fine needle aspiration of thyroid revealed a smear suspicious for malignancy. She underwent total thyroidectomy which revealed CMV PTC. [ncbi.nlm.nih.gov]

  At the genomic medicine clinic, she underwent standard karyotyping, array comparative genomic hybridization, fluorescent in situ hybridization analysis, colonoscopy, endoscopy, thyroid ultrasound, and thyroid fine needle aspiration biopsy. [nature.com]

  […] endoscopic retrograde cholangiopancreatography (ERCP) may be necessary to evaluate for adenomas of the common bile duct; annual physical examination with palpation of the thyroid with consideration of follow-up ultrasound examination and fine-needle aspiration [en.wikipedia.org]

• Abdominal Pain

  A 38-year-old lady presented with abdominal pain, diarrhoea and iron deficiency anemia. There was no history of colorectal cancer in the family. [ncbi.nlm.nih.gov]

  This disease can become active in childhood with the development of adenomatous polyps causing bleeding with bowel movements, diarrhea, or abdominal pain usually in the mid teenage years however, exceptions are the rule. [nationwidechildrens.org]

  pain, anemia, and/or mucosal discharge 4. [radiopaedia.org]

  Other non-specific complaints such as change in bowel habits, constipation, diarrhea and abdominal pain may occur. 75 to 80% of affected individuals have a family history of polyps or colorectal cancer at age 40 years or younger. [symptoma.com]

  Abnormal signs and symptoms that may develop in the course of the disease include: rectal bleeding abdominal pain diarrhea anemia If your child has FAP, they may have other abnormal growths or lesions in other areas of the body, such as the thyroid, eyes [childrenshospital.org]

• Hematochezia

  A 34-year-old man was referred to our department with a 6-year history of intermittent hematochezia without any other discomfort after undergoing partial colectomy in February 2013, and 5 endoscopic mucosal resections of colon polyps between May 2012 [ncbi.nlm.nih.gov]

  Symptoms are uncommon until the adenomas are large and numerous causing hematochezia or anemia. [symptoma.com]

  The most common clinical presentation in children with colonic polyposis was hematochezia. A family history of colonic polyposis was noted in 7 children. The colonoscopic findings of colonic polyposis varied with the size and number of polyps. [kci.go.kr]

  Nonspecific symptoms, such as unexplained rectal bleeding (hematochezia), diarrhea, or abdominal pain, in young patients may be suggestive of FAP. Video Endoscopic Sequence 8 of 12. [gastrointestinalatlas.com]

  In 1995, An et al ( 83 ) reported that 15 patients diagnosed with CFAP receiving TCM through oral administration and retention enema exhibited a reduction in clinical CFAP symptoms, including diarrhea and hematochezia. [spandidos-publications.com]

• Blood in Stool

  It is important to note that presence of blood in stool does not mean that the individual has colon cancer because blood may also be present in stool as a result of many non-cancer conditions Hence, a colonoscopy with a tissue biopsy is required to make [dovemed.com]

• Retinal Pigmentation

  The pigmented fundus lesions associated with familial adenomatous polyposis (FAP) often resemble those characteristic of congenital hypertrophy of the retinal pigment epithelium (CHRPE). [ncbi.nlm.nih.gov]

  Patient's afflicted with FAP have an increased risk for other health problems that include: polyps in the upper gastrointestinal tract, osteomas, epidermoid cysts, desmoid tumors, hypertrophy of retinal pigment, dental abnormalities, thyroid cancers, [stanfordhealthcare.org]

  […] in the abdominal wall following local surgery / trauma May develop bone lesions (i.e. osteomas), skin lesions (i.e. epidermal inclusion cysts), dental abnormalities (i.e. supranummary or absent teeth), ocular problems (i.e. congenital hypertrophy of retinal [pathologyoutlines.com]

  Additional findings may include dental anomalies, polyps of the gastric fundus and duodenum, and congenital hypertrophy of the retinal pigment epithelium (CHRPE). [ltd.aruplab.com]

Diagnosis is based on family history, clinical findings and large bowel endoscopy or full colonoscopy. Barium enema and virtual colonoscopy can also be used to suggest the diagnosis of FAP. The clinical diagnosis should be confirmed by genetic testing. Familial Adenomatous Polyposis is diagnosed in a patient with one of the following:

• One hundred or more colorectal adenomatous polyps
• Fewer than 100 adenomatous polyps and a relative with FAP or 10 to 100 adenomatous polyps and a first degree relative with FAP
• Detection of a germline mutation in the APC gene

Periodic ultrasounds or computed tomography scans are used to check for intra-abdominal desmoid tumors and thyroid or pancreatic cancer.

• Polyps

  People with the autosomal recessive type of this disorder have fewer polyps than those with the classic type. Fewer than 100 polyps typically develop, rather than hundreds or thousands. [rxlist.com]

  (Absence of polyps does not 'clear' a person, as polyps can develop later in life; also a few polyps over time are not that uncommon in people without FAP. [en.wikipedia.org]

  People with FAP develop hundreds to thousands of pre-cancerous polyps (adenomas) in the colon from early adolescence. These polyps are highly prone to becoming cancerous. [genomicseducation.hee.nhs.uk]

  A mutation in the APC gene causes this condition as well, but AFAP patients have fewer polyps than FAP patients — usually less than 100. Polyps and colorectal cancer start in AFAP patients at an average age of 44 and 56, respectively. [mskcc.org]

Treatment for the disorder depends on the genotype. Monitoring is mainly based on endoscopic surveillance to detect the onset of polyposis. Prophylactic colectomy in FAP is usually performed shortly after polyps are discovered.

Several surgical options exist: total abdominal colectomy with ileorectal anastomosis, total proctocolectomy with ileal pouch anal anastomosis, total proctocolectomy with end ileostomy and total proctocolectomy with continent ileostomy [7] [8] [9].

FAP patients have a higher likelihood of dying than their age-matched healthy counterparts. Causes of FAP-related morbidity include perioperative complications, duodenal/periampullary malignancy, and desmoids.

Familial adenomatous polyposis is caused by different inheritance patterns and different genetic mutations. Mutations in the APC tumor suppressor gene cause classic familial adenomatous polyposis and attenuated familial adenomatous polyposis. Mutations in the MUTYH gene are associated with autosomal recessive familial adenomatous polyposis [3].

The reported incidence of familial adenomatous polyposis varies from 1 in 7,000 to 1 in 22,000 individuals worldwide. The mean age for the development of colon cancer in the untreated individual is 39 years. Males and females are equally affected [2].

Colorectal cancer and diffuse mesenteric fibromatosis are the two main causes of mortality. Diffuse mesenteric fibromatosis is reported in 4 to 32% of patients.

Mutations in the APC gene cause both classic and attenuated familial adenomatous polyposis. APC is a tumor suppressor protein that plays a central role in Wnt-1 signaling, in part by regulating the degradation of β-catenin, a protein that stimulates cell growth.

More than 300 different types of mutations are recognized today as the cause of FAP. Most of these mutations result in a truncated and nonfunctional protein. The most common mutation, occurring in about 10% of FAP patients, is a deletion mutation in codon 1309. The number of polyps and the time frame in which they become malignant depend on the location of the mutation in the gene. APC mutations have also been linked to other certain cancers such as pancreatic or gastric adenocarcinomas or thyroid cancer [4] [5] [6].

Autosomal recessive FAP is characterized by a slightly increased risk of developing colorectal cancer and adenomas in both the upper and lower gastrointestinal tract and is caused by the inheritance of mutations in the base-excision-repair gene MUTYH. The phenotype of Autosomal recessive FAP is often indistinguishable from the other forms.

There are no guidelines for prevention of FAP.

Familial adenomatous polyposis (FAP) is an autosomal dominant inherited condition in which numerous adenomatous polyps form in the epithelium of the colon. These polyps transform into colon cancer if left untreated.

There are three variants known existed. First, the classic familial adenomatous polyposis itself. Second, “attenuated FAP” (originally called “hereditary flat adenoma syndrome”). These two conditions are caused by APC gene defects, a tumor suppressor gene that is located on band 5q21. Third, the “autosomal recessive FAP” (or “MYH-associated polyposis (MAP)”) which is caused by MUTYH gene defects. The classic familial adenomatous polyposis is the most common and most severe form [1].

The presence of extracolonic manifestations is variable and may include gastric and duodenal polyps, dental abnormalities, congenital hypertrophy of the retinal pigment epithelium (CHRPE), osteomas, benign cutaneous lesions, diffuse mesenteric fibromatosis, hepatoblastoma, and extracolonic cancers.

Familial adenomatous polyposis is a rare genetic condition that causes polyps to form in the intestines. If untreated, these polyps almost always turn into cancer, usually by age 40.

FAP affects approximately 1 in 10,000 people, men and women equally. The majority of cases are due to a mutation in the adenomatous polyposis coli (APC) gene. Most people with familial adenomatous polyposis need surgery to remove the colon with all its polyps to prevent cancer.

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4. Carter MA. Patient-provider relationship in the context of genetic testing for hereditary cancers. In: Hereditary breast, ovarian, and colon cancer. Journal of the National Cancer Institute monographs. No. 17. Washington, D.C.: Government Printing Office, 1995:119-21.
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7. Ziv Y, Church JM, Oakley JR, McGannon E, Schroeder TK, Fazio VF. Results after restorative proctocolectomy and ileal pouch anal anastomosis in patients with familial adenomatous polyposis and coexisting colorectal cancer. Br J Surg 1996, 83:1578-1580.
8. Setti-Carraro P, Nicholls RJ. Choice of prophylactic surgery for the large bowel component of familial adenomatous polyposis (Review). Br J Surg 1996, 83:885-892.
9. Kartheuser A, Parc R, Penna C, Tiret E, Frileux P, Hannoun L, Nordlinger B, Loygue J. Ileal pouch-anal anastomosis as the first choice operation in patients with familial adenomatous polyposis. A ten years experience. Surgery 1996, 119:615-23.