Decision analysis in the surgical treatment of patients with familial adenomatous polyposis: a Dutch-Scandinavian collaborative study including 659 patients

Background and aims-The choice of colorectal surgery in patients with famil ial adenomatous polyposis lies between the morbidity of proctocolectomy and ileum-pouch-anal anastomosis (IPAA) and the mortality from rectal cancer a fter total colectomy and ileorectal anastomosis (IRA). The aims of the pres ent study were: (1) to assess the risk of dying from rectal cancer after IR A, (2) to compare the life expectancy between patients with an IRA and thos e with an IPAA, and (3) to investigate whether regular endoscopic examinati on of the rectum leads to detection of cancer at an earlier stage. Methods - Clinical and pathological data on 659 patients who underwent cole ctomy and ileorectal anastomosis were collected from four national polyposi s registries-that is, in Denmark, Finland, Sweden, and the Netherlands. Dat a were analysed using survival analysis methods. Decision analysis was used to compare the life expectancy between patients with an IRA and those with an IPAA. Results - A total of 47 patients developed rectal cancer after IRA. The ris k of dying from rectal cancer was 12.5% (95% confidence interval 7.1-17.9%) by age 65. Compared with IRA, IPAA would lead to an increase in life expec tancy of 1.8 years. Seventy five per cent of patients with rectal cancer ha d a negative rectoscopy within 12 months before the diagnosis. Conclusion - IRA is associated with substantial mortality due to rectal can cer. Follow up examinations of the rectum does not have sufficient preventi ve effect on morbidity and mortality of rectal cancer.