familial adenomatous polyposis

Familial Adenomatous Polyposis (FAP): A Rare Inherited Condition

Familial adenomatous polyposis (FAP) is a rare, inherited condition characterized by the development of hundreds to thousands of precancerous polyps in the colon and rectum [1][2]. This genetic disorder is caused by a defect in the adenomatous polyposis coli (APC) gene, which increases the risk of developing colon cancer [3].

Key Features of FAP:

• Inherited condition: FAP is an autosomal dominant inherited disorder, meaning that if one parent has the condition, each child has a 50% chance of inheriting it [4].
• Multiple polyps: Hundreds to thousands of precancerous polyps form on the inner walls of the colon and rectum, increasing the risk of colon cancer [5][6].
• Early onset: Polyps usually start to appear when a person is in their teenage years or early twenties [7].

Consequences of FAP:

• High risk of colon cancer: If left untreated, FAP can lead to the development of colon cancer due to the high number of precancerous polyps [8].
• Early onset of symptoms: Individuals with FAP may experience symptoms such as abdominal pain, blood in stool, and changes in bowel habits at a younger age than those without the condition [9].

References:

[1] Jun 30, 2021 — Familial adenomatous polyposis (FAP) is a rare, inherited condition caused by a defect in the adenomatous polyposis coli (APC) gene. [2] Oct 1, 2013 — Familial adenomatous polyposis (FAP) is an inherited disorder characterized by cancer of the large intestine (colon) and rectum. [3] Familial adenomatous polyposis (FAP) is a hereditary syndrome that predisposes you to developing colon cancer. The lifetime risk is near 100%. [4] by S Carr · 2023 · Cited by 40 — Familial adenomatous polyposis is an autosomal dominant polyposis syndrome characterized by mutations in the adenomatous polyposis coli gene. [5] Familial adenomatous polyposis (FAP) is a rare inherited cancer predisposition syndrome characterized by hundreds to thousands of precancerous colorectal polyps ... [6] An inherited disorder in which many polyps (usually hundreds to thousands) form on the inner walls of the colon and rectum. Polyps are abnormal growths that ... [7] FAP causes hundreds or thousands of small growths in the the large bowel. These are called polyps or adenomas. They usually start to appear when a person is in ... [8] Apr 16, 2019 — It is an autosomal dominant inherited disorder characterized by the early onset of hundreds to thousands of adenomatous polyps throughout the colon. [9] Familial adenomatous polyposis (FAP) leads to the growth of hundreds to thousands of non-cancerous (benign) polyps in the colon and rectum.

Common Signs and Symptoms of Familial Adenomatous Polyposis (FAP)

Familial adenomatous polyposis (FAP) is a rare inherited cancer predisposition syndrome characterized by the growth of hundreds to thousands of precancerous polyps in the colon and rectum. The symptoms of FAP can vary from person to person, but here are some common signs and symptoms:

• Rectal bleeding: One of the most common symptoms of FAP is rectal bleeding, which can be caused by the rupture of a polyp or the erosion of the rectal mucosa.
• Abdominal pain: Abdominal pain, cramping, and vomiting are also common symptoms of FAP. This can be due to the pressure exerted by the growing polyps on the surrounding tissue.
• Diarrhea: Some people with FAP may experience diarrhea, which can be caused by the inflammation and irritation of the rectal mucosa.
• Anemia: As a result of chronic bleeding, some individuals with FAP may develop anemia, which can cause fatigue, weakness, and shortness of breath.

Other Possible Symptoms

In addition to these common symptoms, people with FAP may also experience:

• Dental abnormalities: Some individuals with FAP may have dental abnormalities, such as missing teeth or extra teeth.
• Desmoid tumors: Desmoid tumors are a type of benign tumor that can occur in the abdominal wall and other areas.
• Duodenal tumors: Malignant tumors can also develop in the duodenum (the first part of the small intestine).

Early Detection is Key

It's essential to detect FAP early, as it can lead to colorectal cancer if left untreated. If you or a family member has a history of FAP, it's crucial to undergo regular screening and monitoring.

References:

• [4] Familial adenomatous polyposis (FAP) is a rare inherited cancer predisposition syndrome characterized by hundreds to thousands of precancerous colorectal polyps.
• [6] What are the symptoms of FAP? · Rectal bleeding · Abdominal pain · Diarrhea · Anemia.
• [8] Sep 19, 2022 — What are the symptoms of familial adenomatous polyposis? The primary sign of FAP is the development of hundreds to thousands of polyps. Common symptoms include rectal bleeding, abdominal pain, and diarrhea.
• [9] Result: constipation | anorectal bleeding | general abdominal pain, cramps, or spasms | weight loss | blood in stool

Familial adenomatous polyposis (FAP) can be diagnosed through various diagnostic tests, which are essential for early detection and treatment.

• Genetic testing: This is the primary method for diagnosing FAP. A blood sample is taken to check for an APC gene variant, which is responsible for the condition [1]. If you have a family history of FAP, genetic testing can also identify carriers of the mutated gene [4].
• Digital Rectal Exam (DRE): This test involves a doctor inserting a gloved finger into the rectum to feel for polyps or other abnormalities in the colon [2].
• Fecal Occult Blood Test: This is a simple blood test that can detect hidden blood in the stool, which may indicate the presence of polyps or cancer [2].
• Flexible Sigmoidoscopy: This procedure involves inserting a flexible tube with a camera into the rectum to visualize the inside of the colon and identify polyps or other abnormalities [2].
• Colonoscopy: This is a more detailed examination of the entire colon using a flexible tube with a camera, which can help detect polyps, cancer, or other conditions [2].

It's essential to note that these diagnostic tests are typically recommended for individuals with a family history of FAP or those who have already developed symptoms. Regular screening and monitoring are crucial for early detection and treatment.

References: [1] Jun 30, 2021 — A simple blood test can determine if you carry the abnormal gene that causes FAP. [2] Digital Rectal Exam · Fecal Occult Blood Test · Flexible Sigmoidoscopy · Colonoscopy [4] FAP is usually diagnosed by genetic testing. A sample of blood is checked for an APC gene variant.

Note: The above information is based on the search results provided in the context, and it's essential to consult a healthcare professional for accurate diagnosis and treatment.

Treatment Options for Familial Adenomatous Polyposis (FAP)

Familial adenomatous polyposis (FAP) is a genetic disorder that leads to the growth of hundreds of polyps in the gastrointestinal tract, increasing the risk of colorectal cancer. While surgery is often the primary treatment for FAP, there are also some drug treatments available to help manage the condition.

Pharmacological Treatment

Research suggests that certain medications may be effective in reducing the number and size of adenomatous polyps remaining in the rectum or ileal pouch after colectomy (surgery) in patients with FAP [8]. Some of these medications include:

• Sulindac: A nonsteroidal anti-inflammatory drug (NSAID) that has been shown to cause regression of adenomatous polyps [8].
• Celecoxib: A selective cyclo-oxygenase-2 inhibitor that may also be effective in reducing the number and size of adenomatous polyps [3].
• Aspirin: Another NSAID that may have a role in preventing colorectal cancer in patients with FAP [8].

Combination Therapy

A combination treatment of erlotinib (Tarceva) and sulindac has been shown to decrease the number and size of adenomatous polyps remaining after colectomy in patients with FAP [6]. However, more research is needed to confirm the efficacy and safety of this approach.

Current Limitations

It's essential to note that there are currently no approved drugs specifically designed to treat familial adenomatous polyposis [9]. Therefore, treatment options for FAP remain limited, and surgery often remains the primary treatment approach.

References:

[3] by P Luo · Cited by 1 — Conclusion: The most effective treatment for reducing the number of colorectal polyps is celecoxib 16 mg/kg/day. On the other hand, a daily dosage of sulindac 150 mg was not effective in reducing the number of polyps.

[6] Aug 25, 2023 —

Understanding Differential Diagnosis in Familial Adenomatous Polyposis (FAP)

Familial adenomatous polyposis (FAP) is a rare inherited cancer predisposition syndrome characterized by hundreds to thousands of precancerous colorectal polyps. When diagnosing FAP, it's essential to consider differential diagnoses that can mimic or coexist with the condition.

Differential Diagnoses for FAP:

• MUTYH-associated polyposis (MAP): This autosomal recessive polyposis syndrome is a significant differential diagnosis of APC-associated FAP. MAP is characterized by multiple polyps in the colon and rectum, similar to FAP.
• Peutz-Jeghers Syndrome: This hereditary disorder causes multiple hamartomatous polyps throughout the gastrointestinal tract, as well as distinctive mucocutaneous melanin deposits. While it shares some similarities with FAP, Peutz-Jeghers syndrome is a distinct entity.
• Neurofibromatosis Type 1 (NF1): NF1 is an autosomal dominant disorder that can cause multiple polyps in the colon and rectum, among other manifestations. However, NF1 is primarily characterized by neurofibromas, café-au-lait spots, and other systemic features.
• Cronkhite-Canada Syndrome: This rare condition is characterized by multiple hamartomatous polyps throughout the gastrointestinal tract, as well as skin changes and alopecia.

Key Considerations for Differential Diagnosis:

When considering differential diagnoses for FAP, it's essential to evaluate the following factors:

1. Number and distribution of polyps: The presence of hundreds to thousands of polyps in the colon and rectum is a hallmark of FAP.
2. Polyp histology: FAP is characterized by adenomatous polyps, whereas other conditions may have hamartomatous or inflammatory polyps.
3. Family history: A strong family history of colorectal cancer or polyposis syndromes can suggest an inherited component to the condition.
4. Systemic manifestations: Conditions like Peutz-Jeghers syndrome and NF1 often present with systemic features beyond gastrointestinal polyps.

References:

• [11] MUTYH-associated polyposis (MAP) is the most important differential diagnosis of APC-associated FAP (e16– e18).
• [12] Differential diagnosis of FAP. There are other disorders causing multiple polyps.
• [13] This topic will review the genetics, clinical manifestations, and diagnosis of FAP and its variants (attenuated FAP [AFAP], and gastric ...
• [14] Diagnosis of FAP is based on having at least 100 polyps, or 20 for AFAP, and the APC mutation.