Diagnosis
Familial adenomatous polyposis (FAP) may be suspected based on family history or when multiple polyps are found in the colon.
A person is at risk of FAP if a parent, child, brother or sister has the condition. For those at risk, regular screening is important and often begins in childhood. Ongoing exams can detect polyp growth early, before cancer develops.
Genetic testing
A diagnosis of FAP or disease caused by other variants can be confirmed with genetic testing. Genetic testing looks for a change, called a variant, in the APC gene. This test is usually done with a blood sample.
Genetic testing is recommended for:
- People who have many colon polyps.
- People who have a family history of FAP.
- Children and blood relatives of someone diagnosed with FAP. Blood relatives are family members such as parents, siblings and cousins.
Testing can confirm the diagnosis and help identify other family members who may be at risk.
Colon and rectum screening
Screening tests are used to look for polyps in the colon and rectum. These tests often begin in late childhood or the early teenage years for those at risk.
- Colonoscopy. A flexible tube with a camera is used to look at the entire colon. This test is usually repeated every 1 to 2 years to monitor for new polyps.
- Sigmoidoscopy. A test similar to colonoscopy may be used to examine the lower part of the colon, especially in younger people.
These tests help detect polyps early and guide treatment decisions.
Upper gastrointestinal screening
Polyps also can develop in the stomach and small intestine. Screening for these may include an upper endoscopy. During this procedure, a flexible tube is used to look at the esophagus, stomach and duodenum. This testing typically begins in early adulthood, around age 20 to 25, and is repeated at intervals based on the findings.
Additional tests
Other tests may be recommended to check for related conditions:
- Thyroid exam and ultrasound. These tests are used to look for thyroid changes.
- Imaging tests, such as CT or MRI. These tests may be used to check for desmoid tumors.
Treatment
Treatment for familial adenomatous polyposis (FAP) focuses on reducing the risk of cancer and managing polyp growth.
Early in the condition, small polyps found during colonoscopy may be taken out. Over time, however, the number of polyps usually increases and becomes too large to manage individually, often by the late teens or early 20s. At that point, surgery is recommended to prevent colorectal cancer.
Surgery also may be needed if a polyp becomes cancerous. In some cases of attenuated familial adenomatous polyposis (AFAP), surgery may be delayed or not needed right away, depending on the number and features of the polyps.
Surgery
Surgery is the main treatment for FAP because of the high likelihood of colorectal cancer. The goal is to remove the at-risk tissue while preserving quality of life.
- Colectomy with ileorectal anastomosis. This surgery removes the colon but keeps the rectum. The small intestine is connected to the rectum. This option may be used when the rectum has fewer polyps and can be managed with ongoing screening.
- Proctocolectomy with ileal pouch-anal anastomosis. This procedure removes both the colon and the rectum. A pouch, often called a J-pouch, is created from the small intestine and connected to the anus to allow stool to pass without creating an opening in the abdomen, called an ostomy.
- Proctocolectomy with ileostomy. This surgery removes the colon and rectum and brings the end of the small intestine to an opening in the abdomen, called an ileostomy. Waste is then collected in a bag outside the body.
The type and timing of surgery depend on the number, size and features of the polyps, as well as individual preferences and overall health.
Medications
You may take medicines to help lessen the number of polyps or slow their growth. These treatments are most often used along with surgery and screening, not as a replacement.
- Nonsteroidal anti-inflammatory drugs (NSAIDs). Medicines such as sulindac or celecoxib may lessen the number and size of polyps. These uses are considered off-label. However, these medicines do not eliminate cancer risk and do not replace surgery.
- Other medicines. Sometimes, additional medicines may be used, especially for related conditions such as desmoid tumors. These may include targeted therapies or other treatments recommended by a specialist.
Treatment of related conditions
Additional treatment may be recommended based on screening results and the features of FAP.
- Duodenal and periampullary polyps. Polyps in the upper small intestine may be taken out using endoscopy or surgery. This can include polyps in the duodenum and the ampulla. Removal may be recommended if the polyps have features that increase the risk of cancer.
- Desmoid tumors. Treatment often begins with medicines, such as NSAIDs or other therapies. More treatments, including chemotherapy or surgery, may be needed if the tumors cause symptoms or continue to grow.
- Osteomas. These noncancerous bone growths may be removed if they cause pain or for cosmetic reasons.
Regular screening
Even after treatment, you need regular screening to monitor for new polyps and related conditions.
- Lower gastrointestinal screening. The remaining rectum or surgically created pouch is regularly checked for new polyps.
- Upper gastrointestinal screening. Endoscopy is used to monitor the stomach and small intestine for polyps.
- Other screening. Additional exams, such as thyroid evaluation or imaging, may be recommended based on individual risk.
Coping and support
Living with familial adenomatous polyposis (FAP) can be challenging. The condition often requires lifelong screening, medical care and, for some people, surgery.
These steps may help:
- Build a healthcare team. Work with healthcare professionals who have experience with hereditary cancer conditions. This may include specialists in gastroenterology, surgery and genetics.
- Stay on track with screening. Keeping regular appointments can help detect changes early and guide treatment.
- Learn about the condition. Understanding FAP can help with decision-making and reduce uncertainty.
- Seek emotional support. It may help to talk with a counselor, psychologist or support group, especially when facing major treatment decisions.
- Talk with family members. Because FAP is inherited, sharing information with blood relatives, such as siblings and cousins, can help them understand their own risk and consider testing.
- Consider genetic counseling. A genetic counselor can help explain testing, results, and what they mean for you and your family.
Preparing for your appointment
Appointments for familial adenomatous polyposis (FAP) may involve discussion of screening, genetic testing and treatment options. Being prepared can help you get the most from your visit.
What you can do
- Gather family history. Bring information about blood relatives, such as parents, grandparents and siblings, who have had colon polyps, colorectal cancer or other related conditions, including their age at diagnosis if known.
- List symptoms and concerns. Write down any symptoms, even if they do not seem related, along with questions you want to ask.
- Bring test results. If you have had prior colonoscopies, imaging or genetic testing, bring copies of those results if available.
- Make a list of your medicines. Include all prescription and nonprescription medicines, vitamins, and supplements.
- Consider bringing someone with you. A family member or friend can help remember information and provide support.
Questions to ask your doctor
- What tests do you recommend to confirm or monitor FAP?
- How often should I have screening?
- What treatment options are available, and when might surgery be needed?
- Should I consider genetic testing?
- What does this mean for family members?