Mucin expression in the ileoanal reservoir reflects incomplete mucosal adaptation

Incidence and Risk Factors of Cancer in the Anal Transitional Zone and Ileal Pouch following Surgery for Ulcerative Colitis and Familial Adenomatous Polyposis

Proctocolectomy with ileal pouch-anal anastomosis is the intervention of choice for ulcerative colitis and familial adenomatous polyposis requiring surgery. One of the long-term complications is pouch cancer, having a poor prognosis. The risk of high-grade dysplasia and cancer in the anal transitional zone and ileal pouch after 20 years is estimated to be 2 to 4.5% and 3 to 10% in ulcerative colitis and familial polyposis, respectively. The risk factors for ulcerative colitis are the presence of pre-operative dysplasia or cancer, disease duration > 10 years and severe villous atrophy. For familial polyposis, the risk factors are the number of pre-operative polyps > 1000, surgery with stapled anastomosis and the duration of follow-up. In the case of ulcerative colitis, a pouchoscopy should be performed annually if one of the following is present: dysplasia and cancer at surgery, primary sclerosing cholangitis, villous atrophy and active pouchitis (every 5 years without any of these factors). In the case of familial polyposis, endoscopy is recommended every year including chromoendoscopy. Even if anal transitional zone and ileal pouch cancers seldom occur following proctectomy for ulcerative colitis and familial adenomatous polyposis, the high mortality rate associated with this complication warrants endoscopic monitoring.

Systematic review of dysplasia after restorative proctocolectomy for ulcerative colitis

Background

The aim of this systematic review was to assess the prevalence and site of dysplasia after restorative proctocolectomy (RPC) for ulcerative colitis (UC), and to identify risk factors that could be used in a surveillance programme.

Methods

Medical databases were searched for potentially relevant publications between 1978 and 2006. Studies that dealt with RPC for UC and postoperative surveillance were included. Two researchers independently performed study selection, quality assessment, data extraction and analysis.

Results

Twenty-three observational studies and case series were included, with a total of 2040 patients. The pooled prevalence of confirmed dysplasia in the pouch, anal transitional zone or rectal cuff was 1·13 (range 0–18·75) per cent. The prevalence of high-grade dysplasia, low-grade dysplasia and indefinite for dysplasia was 0·15 (range 0–4·49), 0·98 (range 0–15·62) and 1·23 (range 0–25·28 per cent) respectively. Dysplasia was equally frequent in the pouch and rectal cuff or anal transitional zone. Dysplasia and cancer identified before or at operation seemed to be significant predictors of the development of dysplasia. Pouchitis and duration of follow-up were not of predictive value.

Conclusion

Although based on low-level evidence from uncontrolled studies, the prevalence of dysplasia observed after RPC was remarkable. A surveillance programme that takes into account the risk factors found is therefore advocated.

Prophylactic surgery for patients with longstanding ulcerative colitis. Which option? Histopathological and clinical implications

Patients with longstanding chronic ulcerative proctocolitis are at risk to develop colorectal cancer Conflicting views as regards surveillance, the indications for surgery and type of preventive procedure exist. For permanent prevention of cancer development complete removal of all potential malignant colorectal mucosa has to be done. Panprocto-colectomy with a conventional ileostomy or continent ileostomy removing all colorectal mucosa should therefore eliminate further risks of colorectal cancer. Colectomy and ileorectal anastomosis is a controversial issue. While many surgeons today are reluctant to use the technique, emphasising the persistent cancer risk, others consider the operation a viable alternative when used on a selective basis. The long-term risk of cancer in the rectal stump is the main strong argument . In restorative proctocolectomy, i.e. proctocolectomy with construction of an ileopouch anal anastomosis residual rectal mucosa is left behind irrespective of technique used and is therefore at risk for cancer development. Quite a few cancers have been reported to occur in these patients but controversy exists as regards the origin of these tumours but the risk for cancer development is very low. Biopsies from ileal pouches demonstrate various histopathological changes from nearly normal mucosa, to inflammation and atrophy, inflammatory cell changes, dysplasia as well as development of carcinoma. Grading of type and atypia is a challenge to reproduce and requires the participation of experienced gastrointestinal histopathologists.