Rectal cancer risk in patients treated for familial adenomatous polyposis

Abstract

Total colectomy with ileorectal anastomosis (IRA) in familial adenomatous polyposis (FAP) leaves patients at risk for rectal cancer. To assess this risk, the rectal cancer incidence in 297 patients with FAP undergoing IRA since 1951 was determined in the population-based registers of Denmark, Finland and Sweden. At the same time, detailed data on 50 patients with FAP and invasive rectal cancer were obtained from 11 international polyposis registries. The cumulative incidence of rectal cancer was 13.1 per cent at 25 years. The 5-year survival rate of patients with FAP developing rectal cancer was 71 per cent. Combining both studies, the risk of dying from rectal cancer after IRA was 2.0 per cent at 15 years of follow-up. These results justify IRA as primary treatment for most patients; restorative proctocolectomy is preferred for some subgroups. The high all-cause mortality rate observed in this relatively young population necessitates lifelong surveillance of patients with FAP.

Chemopreventive Strategies Using NSAIDs and COX-2 Inhibitors

“…After colectomy, these patients are still at increased risk for the development of rectal stump cancer. 82 Prevention of rectal stump adenomas, and of adenomas in young pre-symptomatic FAP patients are major targets for chemopreventive treatment in FAP.…”

Meta-analysis of observational studies of ileorectal versus ileal pouch–anal anastomosis for familial adenomatous polyposis

“…The risk of rectal cancer in patients with FAP undergoing IRA is due to the remaining rectal stump 3,4 . The long-term risk of developing cancer in the stump increases from 4 per cent at 5 years to 25 per cent at 20 years 5 , leading some to suggest that IRA should be converted to IPAA before the age of 50 years 6 .…”

Outcomes and complications of radiation therapy in patients with familial adenomatous polyposis

“…The cumulative risk of rectal cancer after colectomy in FAP patients has been estimated at 4%, 5.6%, 7.9% and 25% at 5, 10, 15 and 20 years, respectively (10). The 5-year survival rate of patients with FAP diagnosed with rectal cancer after colectomy is reported to be 71% (11). While colorectal cancer is the cause of death in up to 48% of patients dying with a known diagnosis of FAP, those who undergo prophylactic colectomy are more likely to die of desmoid tumors, and periampullary malignancies (12).…”