Outcome of primary and secondary ileal pouch-anal anastomosis and ileorectal anastomosis in patients with familial adenomatous polyposis.

Purpose: The aim of this study was to present Swedish experiences of the ileal pouch-anal anastomosis in patients with familial adenomatous polyposis from the introduction in 1984. The study also compared the surgical and functional outcome of different anal continence preserving procedures: ileal pouch-anal anastomosis as primary surgery, ileal pouch-anal anastomosis as secondary surgery after colectomy and ileorectal anastomosis, and ileorectal anastomosis alone.

Methods: The material comprises all 120 patients with familial adenomatous polyposis reported to the Swedish Polyposis Registry who had undergone prophylactic colorectal surgery, including those operated on because of colorectal cancer from 1984 until the end of 1996. Anal continence preserving surgery was performed on 102 patients: 20 had ileal pouch-anal anastomosis as primary surgery at a median age of 24.5 years, 39 had ileal pouch-anal anastomosis as secondary surgery at a median age of 34 years, and 43 had ileorectal anastomosis alone, at a median age of 26 years, because 6 of the initially ileorectal anastomosis-operated patients were converted to ileal pouch-anal anastomosis as secondary surgery. Surgical outcome was assessed on the basis of hospital records. A questionnaire was used to evaluate the functional outcome. Fisher's exact probability test was used for statistical analysis.

Results: Complications occurred in 51 percent of the patients after ileal pouch-anal anastomosis: 40 percent after ileal pouch-anal anastomosis as primary surgery and 56 percent after ileal pouch-anal anastomosis as secondary surgery. When the previous ileorectal anastomosis was taken into account 67 percent of the patients suffered complications which was significantly more compared with ileal pouch-anal anastomosis as primary surgery. After ileorectal anastomosis, 26 percent had complications which was significantly less compared with all other procedures but ileal pouch-anal anastomosis as primary surgery. No cancer occurred after ileal pouch-anal anastomosis, either in the ileal pouch or in retained rectal mucosa, but two of the patients who had an ileorectal anastomosis developed rectal cancer. One pouch excision was performed compared with ten rectal excisions. Functional outcome did not differ between ileal pouch-anal anastomosis as primary surgery and ileal pouch-anal anastomosis as secondary surgery. However, ileorectal anastomosis-operated patients had significantly better bowel function with regard to nighttime stool frequency, continence and perianal soreness.

Conclusion: These findings indicate that major advantages of ileal pouch-anal anastomosis are the low excision rate and, so far, no cancer in the ileal pouch. Moreover, the surgical outcome of ileal pouch-anal anastomosis as primary surgery is not significantly different from that of ileorectal anastomosis. However, the good surgical and functional outcome of ileorectal anastomosis, despite the long-range prognosis including rectal cancer and excision risks, has to be taken into consideration when selecting patients with familial adenomatous polyposis for primary surgery.