Familial adenomatous polyposis (FAP) is a dominantly inherited condition caused by germline mutation of the APC gene resulting in formation of numerous large bowel adenomas in late childhood or adolescence. Unless these are removed, colorectal cancer inevitably develops. Prophylactic surgical treatment is required to prevent this. In surgical decision making, considerations should include genotype-phenotype correlation, perioperative morbidity and risk of impaired sexual and reproductive function in young patients after major pelvic surgery. Colectomy with ileorectal anastomosis remains an appropriate prophylactic procedure in many patients. However, in those with high-density polyposis or a genotype predictive of aggressive disease, restorative proctocolectomy is preferable. There is a range of other features, as FAP is essentially a systemic disease. These include duodenal and peri-ampullary adenomas and carcinoma, desmoid tumors, papillary-type thyroid carcinoma and pancreatic carcinoma among others. With improved management that reduces the risk of colorectal cancer, these extracolonic manifestations have become of increasing clinical significance. For all FAP patients, including those undergoing proctocolectomy, thorough surveillance is of vital importance as there remains a risk of developing neoplasia. Despite advances in surgical techniques, screening and surveillance, life expectancy in patients with FAP is still less than that of the general population.
Keywords: colorectal cancer; familial adenomatous polyposis; ileoanal pouch; ileorectal anastomosis; restorative proctocolectomy.