familial adenomatous polyposis 4

Familial Adenomatous Polyposis (FAP): A Rare Genetic Disorder

Familial adenomatous polyposis (FAP) is a genetic disorder that predisposes individuals to develop precancerous colon polyps called adenomas. These abnormal growths can lead to cancer of the large intestine (colon) and rectum if left untreated.

Key Features of FAP:

• Genetic Predisposition: FAP is an inherited condition, meaning it can be passed down from parents to children.
• Colon Polyps: Hundreds or thousands of polyps form on the inner walls of the colon and rectum, increasing the risk of cancer.
• Precancerous Lesions: Adenomas are precancerous lesions that can develop into colorectal cancer if not removed.

Symptoms and Risks:

While FAP may not always present with symptoms, individuals with this condition are at a higher risk of developing colon cancer. Other potential symptoms include:

• Dental abnormalities
• Tumors of the connective tissue (desmoid tumors)
• Benign and malignant tumors of the duodenum

Early Detection and Treatment:

Early detection and removal of polyps can prevent colorectal cancer in individuals with FAP. Regular screening and surveillance are essential for managing this condition.

References:

• [4] Familial adenomatous polyposis is a genetic disorder that predisposes you to develop precancerous colon polyps called adenomas.
• [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 ...
• [9] Familial adenomatous polyposis is a hereditary disorder causing numerous colonic polyps and frequently results in colon carcinoma, often by age 40.
• [10] Result: a non-metastasizing neoplasm arising from the wall of the colon

Familial Adenomatous Polyposis (FAP) Signs and Symptoms

FAP, a rare inherited cancer predisposition syndrome, is characterized by the growth of hundreds to thousands of precancerous colorectal polyps in the colon and rectum. The symptoms of FAP can vary from person to person but often include:

• Abdominal pain: Cramping, discomfort, or tenderness in the abdominal area due to the presence of numerous polyps.
• Rectal bleeding: Blood in the stool or on the toilet paper due to the rupture of polyps.
• Diarrhea: Frequent bowel movements or loose stools caused by the irritation and inflammation of the colon.
• Anemia: Low red blood cell count or hemoglobin levels due to chronic blood loss from the polyps.

These symptoms can be quite distressing and may lead to a decrease in quality of life. It's essential for individuals with FAP to seek medical attention promptly, as early detection and treatment can significantly improve outcomes.

References:

• [4] Familial adenomatous polyposis (FAP) is a rare inherited cancer predisposition syndrome characterized by hundreds to thousands of precancerous colorectal polyps...
• [7] What are the symptoms of FAP? · Rectal bleeding · Abdominal pain · Diarrhea · Anemia.

Diagnostic Tests for Familial Adenomatous Polyposis (FAP)

Familial adenomatous polyposis (FAP) is a genetic disorder that increases the risk of developing colorectal cancer. Diagnostic tests are essential to confirm the presence of FAP and monitor its progression.

• Genetic Testing: A simple blood test can determine if you carry the abnormal gene that causes FAP [1]. Genetic testing may also detect whether you're at risk of complications of FAP, such as colorectal cancer [2].
• Clinical Diagnosis: In the absence of genetic testing, a clinical diagnosis can be made if an individual has a family history of FAP or presents with certain findings, such as stomach or large intestine polyps [8].

Early Detection and Monitoring

Regular screening and surveillance for polyps are crucial in managing FAP. A complete blood cell (CBC) count and alpha-fetoprotein (AFP) blood test may be performed to monitor the condition, especially in children with FAP until age 5 years [6].

Prognosis and Treatment

A diagnosis of FAP is now established by molecular genetic testing. Prophylactic colectomy with or without ileal pouch-anal anastomosis (IPAA) is a common treatment approach for individuals with FAP, aiming to prevent colorectal cancer [7].

Treatment Options for Familial Adenomatous Polyposis (FAP)

Familial adenomatous polyposis (FAP) is a genetic disorder characterized by the development of numerous polyps in the colon and rectum. While there are various treatment options available, drug therapy plays a crucial role in managing this condition.

• Sulindac: This nonsteroidal anti-inflammatory agent has been shown to reduce the number of colorectal polyps in individuals with FAP (4). Sulindac works by inhibiting the production of prostaglandins, which are hormone-like substances that promote inflammation and cell growth.
• Celecoxib: Another COX-2 inhibitor, celecoxib has been used to treat FAP, although its effectiveness is still being researched. A high dosage of celecoxib was briefly approved for treating FAP based on a 28% reduction in polyp number (9).
• Erlotinib and Sulindac: In some cases, a combination treatment of erlotinib (Tarceva) and sulindac has been used to decrease the number of colorectal polyps in individuals with FAP (2).

It's essential to note that while drug therapy can help manage FAP, it is often used in conjunction with other treatments, such as surgery. In fact, surgical removal of the colon and rectum is usually recommended for individuals with FAP to prevent cancer development (5).

Differential Diagnoses for Familial Adenomatous Polyposis (FAP)

Familial adenomatous polyposis (FAP) is a rare inherited cancer predisposition syndrome characterized by hundreds to thousands of precancerous colorectal polyps. However, there are other disorders that can cause multiple polyps and should be considered in the differential diagnosis of FAP.

Other Disorders Causing Multiple Polyps

• Peutz-Jeghers Syndrome: This is a rare autosomal dominant disorder characterized by hamartomatous polyps throughout the gastrointestinal tract. It is associated with an increased risk of certain cancers, including colorectal cancer.
• Familial Juvenile Polyposis: This is a rare autosomal dominant disorder characterized by multiple juvenile polyps in the colon and rectum. It is associated with an increased risk of colorectal cancer.
• Hyperplastic Polyposis: This is a rare condition characterized by multiple hyperplastic polyps throughout the colon and rectum. It is associated with an increased risk of colorectal cancer.
• Hereditary Mixed Polyposis Syndromes: This is a rare autosomal dominant disorder characterized by a combination of different types of polyps, including adenomatous, hamartomatous, and hyperplastic polyps. It is associated with an increased risk of colorectal cancer.
• Lynch Syndrome: This is a rare autosomal dominant disorder characterized by an increased risk of certain cancers, including colorectal cancer, due to inherited mutations in DNA mismatch repair genes.

MUTYH-Associated Polyposis (MAP)

MUTYH-associated polyposis (MAP) is the most important differential diagnosis of APC-associated FAP. This autosomal recessive polyposis syndrome is caused by germline pathogenic variants in the MUTYH gene, which encodes a protein involved in DNA repair.

Differential Diagnosis

The differential diagnosis of FAP includes other disorders that can cause multiple polyps and should be considered based on clinical presentation, family history, and genetic testing. A comprehensive evaluation by a multidisciplinary team of healthcare professionals is essential to determine the correct diagnosis and develop an appropriate treatment plan.

References:

• Nakamura Y. Screening guidelines and premorbid diagnosis of familial adenomatous polyposis using linkage. Gastroenterology.
• Registry and screening programs have been shown to be effective in reducing the incidence of colorectal cancer in patients with FAP and other familial polyposis syndromes.