Secondary proctectomy and ileal pouch-anal anastomosis after ileorectal anastomosis for familial adenomatous polyposis.

Conversion of ileorectal anastomosis to ileal pouch-anal anastomosis (IPAA) was indicated in 29 patients with familial adenomatous polyposis but technically impossible in three because of unsuspected pelvic desmoid tumours. There was no operative mortality and overall postoperative morbidity and late complication rates were no different from those in a group of 120 patients who underwent IPAA as a first operative procedure. Unsuspected adenocarcinoma (one invasive, three in situ) was found in four patients. The functional results in patients with IPAA did not differ from those of ileorectal anastomosis before conversion or from those obtained after IPAA as a first-choice procedure. Secondary proctectomy and IPAA can be safely offered to patients with ileorectal anastomosis and a high risk of rectal cancer.