Adenocarcinoma in ileal pouch after proctocolectomy for familial adenomatous polyposis: report of a case

Endoscopic management of patients with familial adenomatous polyposis after prophylactic colectomy or restorative proctocolectomy - systematic review of the literature

BACKGROUND

Patients with familial adenomatous polyposis (FAP) develop early colorectal adenomas and if left untreated, progression to cancer is an inevitable event. Prophylactic surgery does not prevent further development of cancer in the rectal remnant, rectal cuff in patients with ileal pouch anal anastomosis (IPAA) and even on the ileal mucosa of the pouch body. The aim of this review is to assess long-term rates of cancer and adenoma development in patients with FAP after prophylactic surgery and to summarise current recommendations for endoscopic management and surveillance of these patients.

MATERIALS AND METHODS

A systematic literature search of studies from January 1946 through to June 2023 was conducted using the PRISMA checklist. The electronic database PubMed was searched.

RESULTS

Fifty-four papers involving 5010 patients were reviewed. Cancer rate in the rectal remnant was 8.8-16.7% in the western population and 37% in the eastern population. The cumulative risk of cancer 30 years after surgery was 24%. Mortality due to cancer in the rectal remnant is 1.1-11.1% with a 5-year survival rate of 55%. The adenoma rate after primary IPAA was 9.4-85% with a cumulative risk of 85% 20 years after surgery and a cumulative risk of 12% for advanced adenomas 10 years after surgery. Cumulative risk for adenomas after ileorectal anastomosis (IRA) was 85% after 5 and 100% after 10 years. Adenomas developed more frequently after stapled (33.9-57%) compared to hand-sewn (0-33%) anastomosis. We identified reports of 45 cancers in patients after IPAA of which 30 were in the pouch body and 15 in the rectal cuff or at the anastomosis.

CONCLUSIONS

There was a significant incidence of cancer and adenomas in the rectal remnant and ileal pouch of FAP patients during the long-term follow-up. Regular endoscopic surveillance is recommended, not only in IRA patients, but also in pouch patients after proctocolectomy.

Long-term outcomes of pouch surveillance and risk of neoplasia in familial adenomatous polyposis

BACKGROUND

Long-term pouch surveillance outcomes for familial adenomatous polyposis (FAP) are unknown. We aimed to quantify surveillance outcomes and to determine which of selected possible predictive factors are associated with pouch dysplasia.

METHODS

Retrospective analysis of collected data on 249 patients was performed, analyzing potential risk factors for the development of adenomas or advanced lesions ( ≥ 10 mm/high grade dysplasia (HGD)/cancer) in the pouch body and cuff using Cox proportional hazards models. Kaplan-Meier analyses included landmark time-point analyses at 10 years after surgery to predict the future risk of advanced lesions.

RESULTS

Of 249 patients, 76 % developed at least one pouch body adenoma, with 16 % developing an advanced pouch body lesion; 18 % developed an advanced cuff lesion. Kaplan-Meier analysis showed a 10-year lag before most advanced lesions developed; cumulative incidence of 2.8 % and 6.4 % at 10 years in the pouch body and cuff, respectively. Landmark analysis suggested the presence of adenomas prior to the 10-year point was associated with subsequent development of advanced lesions in the pouch body (hazard ratio [HR] 4.8, 95 %CI 1.6-14.1; P = 0.004) and cuff (HR 6.8, 95 %CI 2.5-18.3; P < 0.001). There were two HGD and four cancer cases in the cuff and one pouch body cancer; all cases of cancer/HGD that had prior surveillance were preceded by ≥ 10-mm adenomas.

CONCLUSIONS

Pouch adenoma progression is slow and most advanced lesions occur after 10 years. HGD and cancer were rare events. Pouch phenotype in the first decade is associated with the future risk of developing advanced lesions and may guide personalized surveillance beyond 10 years.

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.

Adenocarcinoma of the ileal pouch mucosa: case report and literature review

PURPOSE

Cancers developing near the site of the ileoanal pouch anastomosis (IPAA) have been reported, but uncommonly in the ileal pouch mucosa itself. We present a recently encountered case of ileal pouch cancer and review the literature to examine the prevalence, risk factors, and natural history of ileal pouch adenocarcinoma as well as pouch surveillance.

METHODS

A chart review of the case from our institution was conducted, and a PubMed search was undertaken for articles describing adenocarcinoma arising from the ileal pouch mucosa.

RESULTS

Twenty articles containing 26 cases were reviewed in addition to our described case. More than half were reported in the last decade. Only three cases were definitively stage 1. All seven patients who underwent regular surveillance were diagnosed with stage 1 or 2 disease. Seventeen patients had neoplasia in their original proctocolectomy specimen and six did not. The mean time from pouch creation to adenocarcinoma was 8.9 years.

CONCLUSIONS

The risk of developing ileal pouch mucosa adenocarcinoma appears low. However, increasing reports of these cancers are concerning as most patients present with advanced disease after many years. Patients with a previous history of dysplasia/cancer may be at increased risk. We believe surveillance after IPAA should include the anal transition zone and the ileal pouch mucosa. The establishment of expert consensus guidelines on pouch surveillance should be considered in the near future.

Risk of ileal pouch neoplasms in patients with familial adenomatous polyposis

Restorative proctocolectomy is the most common surgical option for patients with familial adenomatous polyposis (FAP). However, adenomas may develop in the ileal pouch mucosa over time, and even carcinoma in the pouch has been reported. We therefore reviewed the prevalence, nature, and treatment of adenomas and carcinoma that develop after proctocolectomy in the ileal pouch mucosa in patients with FAP. In 25 reports that were reviewed, the incidence of adenomas in the ileal pouch varied from 6.7% to 73.9%. Several potential factors that favor the development of pouch polyposis have been investigated, but many remain controversial. Nevertheless, it seems certain that the age of the pouch is important. The risk appears to be 7% to 16% after 5 years, 35% to 42% after 10 years, and 75% after 15 years. On the other hand, only 21 cases of ileal pouch carcinoma have been recorded in the literature to date. The diagnosis of pouch carcinoma was made between 3 to 20 years (median, 10 years) after pouch construction. Although the risk of malignant transformation in ileal pouches is probably low, it is not negligible, and the long-term risk cannot presently be well quantified. Regular endoscopic surveillance, especially using chromoendoscopy, is recommended.

Adenoma formation and malignancy after restorative proctocolectomy with or without mucosectomy in patients with familial adenomatous polyposis

BACKGROUND

There is controversy concerning whether or not to perform mucosectomy after IPAA in patients with familial adenomatous polyposis. Although more frequent adenoma formation at the anastomotic site in patients without a mucosectomy is documented, the interpretation of the theoretical reflections and empirical findings are ambiguous.

OBJECTIVE

The aim of this study was to assess the differences in adenoma formation at the anastomotic site and in the ileal pouch among patients with familial adenomatous polyposis after IPAA with or without mucosectomy.

DESIGN

Data were gathered from The Norwegian Polyposis Registry and The Cancer Registry of Norway.

PATIENTS

Sixty-one patients with familial adenomatous polyposis who had IPAA were included in the Norwegian Polyposis Registry.

MAIN OUTCOME MEASURES

The frequency of adenoma development in the pouch or at the anastomotic site was measured.

RESULTS

Thirty-nine patients had a pelvic pouch performed with mucosectomy and 22 patients without. The observational time was 15.5 and 13.7 years. Adenoma formation at the anastomotic site was 4 in 39 and 14 in 22, and the estimated rate was 17% vs 75% (p = 0.0001). One patient without mucosectomy had a cancer (Dukes A) at the anastomotic site. There was no estimated long-term difference in adenoma formation in the ileal pouches between the 2 surgical procedures (38%) (p = 0.10).

LIMITATIONS

The study is retrospective, in part, and relies on data from registries. There is a limited number of cases, and selection bias because of surgeon preference may exist.

CONCLUSION

In patients with familial adenomatous polyposis who undergo IPAA, adenoma formation at the anastomotic site is significantly reduced after mucosectomy. Mucosectomy may be the preferable procedure to prevent adenomas at the anastomotic site.

Adenocarcinomas After Prophylactic Surgery For Familial Adenomatous Polyposis

The incidence of familial adenomatous polyposis (FAP) is one in 7,000 to 12,000 live births. Virtually, all surgically untreated patients with FAP inevitably develop colorectal-cancer in their lifetime because they carry the adenomatous polyposis coli gene. Thus prophylactic proctocolectomy is indicated. Surgical treatment of FAP is still controversial. There are however, four surgical options: ileorectal anastomosis, restorative proctocolectomy with ileal pouch-anal anastomosis, proctocolectomy with ileostomy, and proctocolectomy with continent-ileostomy. Conventional proctocolectomy options largely lie between colectomy with ileorectal anastomosis or ileal pouch-anal anastomosis. Detractors of ileal pouch-anal anastomosis prefer ileorectal anastomosis because of better functional results and quality of life. The functional outcome of total colectomy with ileorectal anastomosis is undoubtedly far superior to that of the ileoanal pouch; however, the risk for rectal cancer is increased by 30%. Even after mucosectomy, inadvertent small mucosal residual islands remain. These residual islands carry the potential for the development of subsequent malignancy. We reviewed the literature (1975-2012) on the incidence, nature, and possible etiology of subsequent ileal-pouch and anal transit zone adenocarcinoma after prophylactic surgery procedure for FAP. To date there are 24 studies reporting 92 pouch-related cancers; 15 case reports, 4 prospective and 5 retrospective studies. Twenty three of 92 cancers (25%) developed in the pouch mucosa and 69 (75%) in anal transit zone (ATZ). Current recommendation for pouch surveillance and treatment are presented. Data suggest lifetime surveillance of these patients.

[Two cases of multiple adenomas in the ileal pouch after total proctocolectomy in patients with familial adenomatous polyposis]

Familial adenomatous polyposis (FAP) is an inherited disease characterized by the development of hundreds of colorectal adenomas, leading to a 100% lifetime risk of colorectal cancer. A prophylactic colectomy is recommended for patients with FAP to prevent colorectal cancer. Four surgical strategies are available for patients with FAP: proctocolectomy with permanent ileostomy, colectomy with ileorectal anastomosis, proctocolectomy with Kochs pouch continent ileostomy (Koch), and restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA). Koch and IPAA, which make ileal pouch, have theoretical advantage of the elimination of the risk of colorectal cancer and adenomas and good functional outcome of reduced defecation frequency. However, recent reports have shown frequent development of adenomas and carcinomas in the ileal pouch after Koch or IPAA. We experienced 2 cases of multiple pouch adenomas after pouch surgery in FAP patients. Both patients were treated with endoscopic mucosal resection without complications. We report these 2 cases with a review of literatures.