Time and type of prophylactic surgery for familial adenomatosis coli.

Data on 61 kinds of familial adenomatosis coli registered in Finland, including 185 affected members, were collected to evaluate the chronological evolution of carcinoma in this disease. The long-term results for 52 patients undergoing colectomy and ileorectostomy were reviewed. Colorectal carcinoma occurred in 105 patients, with cumulative percentages of 1, 6, 16, 28, and 42 at 20, 25, 30, 35, and 40 years of age. Only three out of 50 call-up patients (6%) had a carcinoma, as compared with 62% in the propositi group. No cases of rectal stump carcinomas were recorded after 52 ileorectostomies in a follow-up period of up to 21 years (mean 6 +/- 5 S.D. years). It was concluded that prophylactic colectomy must usually be performed at 20 to 25 years of age, at the latest. Despite conflicting earlier evidence, colectomy and ileorectal anastomosis may still be a viable alternative, providing that the rectal stump is very short (5 to 10 cm) and the surveillance and treatment of all new adenomas is effective.