Familial Adenomatous Polyposis Treatment & Management

Medical care is mainly based on endoscopic surveillance to detect the onset of polyposis. Consequently, surgery would prevent the development of colon cancer. However, in view of the increased risk for the development of other cancers, continued medical follow-up is required with a number of surveillance tests, as colectomy would only address the potential risk of colon cancer.

A number of drugs (eg, celecoxib, sulindac) have been used successfully to reduce the number and the size of polyps in patients with FAP. However, they are insufficient as a primary modality of therapy.

• Endoscopic surveillance

  • Flexible sigmoidoscopy should be performed every 1-2 years starting at age 10-12 years in patients with FAP to document the onset of polyposis.
  • Sigmoidoscopic surveillance and ablation of any polyps in the retained rectum or ileal pouch should be performed every 3-6 months in patients with FAP who have undergone colonic (total or subtotal) resection. There is an increased risk for adenomas and carcinomas in the ileal pouch, as there is increased epithelial cell proliferation at this site as compared to the afferent ileal loop.^[12]
  • Once polyps are detected, colonoscopic surveillance is recommended to remove large polyps in patients who have not had an operation. This is important because surgery (colectomy) is usually deferred until an appropriate psychological age is reached (usually late teenaged years to early twenties). However, if the polyps have advanced histologic features, then early surgery is recommended.
  • Front- and side-view esophagogastroduodenoscopy should be performed every 1-3 years once the diagnosis is made and after surgical therapy. The front-view esophagogastroduodenoscopy allows for the detection of gastric and duodenal polyps. The side-view duodenoscope allows for the examination of the ampulla of Vater.
  • Capsule endoscopy is useful for the surveillance of jejunal-ileal polyps in selected patients but is not recommended for duodenal or ampullary surveillance. Some patients who are at high risk may benefit from screening with endoscopic ultrasound for periampullary and ampullary tumors.^[13]
• Drugs used in the treatment of FAP include sulindac and celecoxib.

  • Because of the association between cyclooxygenase 2 (COX-2) inhibitors (celecoxib is a member of this drug family) and coronary artery disease, celecoxib is no longer widely used.
  • These drugs have no primary role as sole therapy for patients with FAP who have not had surgical therapy. However, in patients with FAP who have had colectomy with ileoanal anastomosis, sulindac or celecoxib may be beneficial in reducing the size and the number of adenomatous polyps in the remaining rectum.
  • The use of other nonsteroidal anti-inflammatory drugs (NSAIDs) and similar drugs is being studied.
  • Cancers of the rectum (in patients who have had subtotal colectomy with ileorectal anastomosis) have been reported with sulindac and celecoxib therapy. Because of the inability to control polyps medically, eventual rectal resection is usually necessary. This is why subtotal colectomy with ileorectal anastomosis (IRA) is not the preferred surgical procedure.
• Screening of family members of patients with FAP should begin by age 12 years. Flexible sigmoidoscopy every 1-2 years until the patient is aged 35 years is adequate, then every 3 years thereafter. Genetic testing may eliminate the need for surveillance in some family members.
• Desmoid tumors (intra-abdominal) may respond to antiestrogen therapy (tamoxifen) and sulindac because estrogen appears to promote their growth.
• Chemotherapy with doxorubicin and dacarbazine may be attempted if no response is observed with other therapies.

Because of the diffuse nature of the polyposis and the inevitability of colorectal cancer, surgical therapy is ultimately required. Surgical therapy should be performed before the typical onset of cancer.

• Colectomy with mucosal proctectomy and ileoanal pouch pull-through (proctocolectomy with ileal pouch-anal anastomosis/IPAA) is the procedure of choice at many centers.

  • This procedure allows retention of rectal function.
  • Other options include subtotal colectomy with ileoanal anastomosis and total proctocolectomy with ileostomy.
• If medical therapy and endoscopic therapy do not control polyp growth, rectal resection may be needed in patients who have a retained rectum (such as in subtotal colectomy). Desmoid tumors may be resected with adequate margins. This generally is reserved for patients with ureteral or intestinal obstruction.

In a study to determine whether surgical treatment outcomes vary between patients with FAP (168 patients) and those with the sporadic form of the disease (110 patients), Johnson et al concluded that for both disorders, endoscopic and local surgical management of duodenal polyps are each followed by a high rate of local recurrence.^[14] Their results also indicated that for patients with either disease, definitive resection via pancreaticoduodenectomy, pancreas-sparing duodenectomy, or segmental duodenectomy are the best means of eradicating polyps and preventing carcinoma.

• A gastroenterologist familiar with FAP should supervise follow-up care. This is important because appropriate surveillance should be pursued to detect and treat other cancers/complications of FAP after surgery.
• Appropriate genetic counseling for both the patients and their family members should be initiated.