Rectal cancer after mucosectomy for ileoanal pouch in 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.

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.

Dispelling misconceptions in the management of familial adenomatous polyposis

Patients with familial adenomatous polyposis require surgical intervention at some point in their lives. The diagnosis is often apparent from their phenotype and family history, however, this is not always the case. Many factors can influence the surgical strategy although the polyposis burden and distribution remain the main consideration. While prophylactic removal of the rectum and colon is often required, sparing the rectum at the index surgery is safe in select patients. This article aims to dispel misconceptions in the diagnosis and treatment of patients with familial adenomatous polyposis.

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.

Risk of neoplastic change in ileal pouches in familial adenomatous polyposis

INTRODUCTION

Neoplastic change in ileal reservoirs after proctocolectomy has been reported in patients with familial adenomatous polyposis. We aim to determine the incidence and progression of neoplastic change in the ileal pouch of familial adenomatous polyposis patients at our institution.

METHODS

A retrospective review of all patients who underwent proctocolectomy for familial adenomatous polyposis with construction of an ileal pouch from 1972 to 2007 was performed. Data and status at follow-up were retrieved from the Mayo Clinic Colorectal Surgery Pouch database.

RESULTS

One hundred seventeen patients were identified with a median age of 26, 52 were male. Ileal reservoirs included J-pouch (a = 104), Kock pouch (n = 9), S-pouch (n = 3), and W-pouch (n = 1). Median follow-up was 125 months. Polyps were biopsied in 33 patients: non-dysplastic polyps (n = 2), low-grade dysplasia (n = 30), and adenocarcinoma (n = 1). No patients had high-grade dysplasia. Median time to development of dysplasia was 149 months. Adenocarcinoma developed in one patient after 284 months. Risk of dysplasia at 10, 20, and 25 years was 17, 45, and 69%, respectively.

CONCLUSION

Though there is a high incidence of low-grade dysplasia in the ileal reservoir in familial adenomatous polyposis patients, high-grade dysplasia and cancer occur rarely. Patients with low-grade dysplasia may still necessitate regular follow-up.

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.

Surgical treatment of familial adenomatous polyposis: experience from a single institution in China

AIM

Surgical options for familiar adenomatous polyposis (FAP) have been standardized in developed countries but are still controversial in China. The aim of this study was to retrospectively evaluate the results of patients with FAP treated in a university hospital.

METHODS

In all 42 consecutive patients with FAP were operated on between May 1988 and June 2008. Median follow up was 7.2 years (2.2-20 years). Of these 33 patients were treated by proctocolectomy and ileal pouch anal anastomosis. A total colectomy with ileorectal anastomosis was undertaken in six and a proctocolectomy with ileostomy in three patients who had invasive rectal cancer.

RESULTS

Postoperative morbidity was insignificant. There were five wound infections, one intestinal obstruction, one anastomotic leakage, one anastomotic stenosis and one refractory pouchitis. One patient died from stroke. Five died from FAP-related disorders, namely, abdominal desmoids, liver metastases and advanced rectal cancer. Desmoid tumor occurred in five patients. Periampullary adenoma and carcinoma developed in four patients. In those with pouch procedure the 24-h bowel movement was 7.14 ± 1.28 (range 5-11) and their 10-year overall survival was 87.5%.

CONCLUSION

A proctocolectomy with ileal pouch anal anastomosis maybe the best choice for FAP patients in China. Surgical expertise, good teamwork and careful long-term follow up are mandatory.

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

Restorative proctocolectomy with ileal pouch-anal anastomosis is one of the surgical treatments of choice for patients with familial adenomatous polyposis. Although the risk of cancer developing in an ileal pouch is not yet clear, a few cases of adenocarcinoma arising in an ileal pouch have been reported. We report a case of adenocarcinoma in ileal pouch after proctocolectomy with ileal pouch-anal anastomosis. A 56-yr-old woman was diagnosed as having familial adenomatous polyposis. Total colectomy with ileorectal anastomosis was performed. Six years later, she underwent completion-proctectomy with ileal J pouch-anal anastomosis including anorectal mucosectomy for rectal cancer. After 7 yr, she presented with anal spotting. Endoscopic biopsies revealed adenocarcinoma at the ileal pouch. Resection of the ileal pouch and permanent ileostomy were performed. The risk of cancer in an ileal pouch and its prevention with regular surveillance must be emphasized.

Adenocarcinoma arising in the middle of ileoanal pouches: report of five cases

Restorative proctocolectomy with ileal pouch-anal anastomosis with or without mucosectomy has become the procedure of choice in patients with long-standing ulcerative colitis complicated by malignancy or medically refractory disease and for familial polyposis syndrome. Some reports have demonstrated the development of malignancy at the ileoanal anastomosis. We present a recent series of five patients who developed adenocarcinoma in the middle of their ileal pouch including the first case of pouch carcinoma in a patient who underwent pouch formation for ulcerative colitis. We discuss their presentation and management. Development of ileal pouch cancers, while rare, has been seen with increasing frequency in our practice. Patients with long-standing ileal pouches may benefit from routine surveillance of the pouch as often as every six months, which can be performed quickly and easily in the office using flexible endoscopy.

Risk of developing adenomas and carcinomas in the ileal pouch in patients with familial adenomatous polyposis

BACKGROUND & AIMS

At present, more than half of patients with familial adenomatous polyposis (FAP) are treated with a proctocolectomy and an ileal pouch-anal anastomosis (IPAA). Originally it was thought that this procedure would eliminate the risk of developing rectal cancer. However, an increasing number of studies reported development of adenoma and carcinoma in the pouch. The aim of this study was to evaluate the long-term risk of developing adenomas and carcinomas in the pouch in a large cohort of Dutch FAP patients.

METHODS

A total of 254 patients with FAP who underwent an IPAA were selected from the Dutch Polyposis Registry. The results of the surveillance examinations and the pathology reports were analyzed. Surveillance with chromoendoscopy was offered to a subgroup of patients.

RESULTS

Full information on follow-up was available in 212 (84%) patients. These patients (56% male) underwent a total of 761 endoscopies. The mean follow-up was 7.9 years (range, 0.4-20.3 years). The cumulative risk of developing an adenoma in the pouch at 10-year follow-up was 45%. Twenty-five patients (11.8%) developed an adenoma with advanced pathology, and 4 (1.9%) developed a carcinoma. The cumulative risk of developing a pouch carcinoma at 10-year follow-up was 1%. A very high prevalence (75.7%) of adenomas was found in a subgroup of patients who were examined with chromoendoscopy.

CONCLUSIONS

This study demonstrated that although the risk of developing adenomas in the pouch after an IPAA is high, the risk of malignant degeneration appears to be low. The use of chromoendoscopy improves the detection of small adenomas.

Review article: restorative proctocolectomy, indications, management of complications and follow-up--a guide for gastroenterologists

BACKGROUND

Restorative proctocolectomy with ileal pouch-anal anastomosis is the procedure of choice for the majority of patients with ulcerative colitis who require surgery. Over 2500 patients in the UK have undergone restorative proctocolectomy. It is now increasingly being performed in district general hospitals as well as in specialist inflammatory bowel disease units. Gastroenterologists are increasingly involved in the management of patients following restorative proctocolectomy.

AIM

To provide gastroenterologists with a clear understanding of the investigation and evidence-based management of complications and the aftercare required in patients who have undergone restorative proctocolectomy.

RESULTS

Following restorative proctocolectomy, most patients have an excellent long-term functional outcome. Pouchitis, pelvic sepsis and poor function are the most common causes of failure. The development of cancer is rare; nevertheless, long-term follow-up is required.

CONCLUSIONS

The investigation and management of patients who develop complications require a multidisciplinary team approach to optimize the outcome. Protocols are suggested for investigation and management of patients with complications and for long-term cancer surveillance.

Increased epithelial cell proliferation in the ileal pouch mucosa of patients with familial adenomatous polyposis

To eliminate the risk of colorectal cancer in patients with familial adenomatous polyposis (FAP), reconstructive proctocolectomy is performed. Although most colonic mucosa is resected during the ileal pouch anal anastomosis, adenomas and carcinomas may develop in the pouch. This may be caused by altered cell kinetics due to intraluminal changes in the pouch. In 32 patients with FAP, biopsy specimens from the mucosa of the pouch and also of the afferent ileal loop were taken. Tissue sections were immunohistochemically processed with the monoclonal antibodies M30 and MIB-1 to assess apoptotic and proliferative indices, respectively. Cell proliferation was also assessed by a modified sign test. There were no significant differences in apoptotic rates between the mucosa of the pouch and the mucosa of the afferent ileal loop. However, cell proliferation was significantly higher in the mucosa of the pouch vs afferent ileal loop, both by using the quantitative (68.3% vs 61.6%, p = 0.001) and semiquantitative methods (p < 0.05). Our newly developed semiquantitative approach outperformed previously described methods. The higher cell proliferation in the pouch as compared to the afferent ileal loop may contribute to the increased risk for adenomas and carcinomas in the pouch of patients with FAP and emphasizes the need for regular endoscopic surveillance.

Should ileal pouch-anal anastomosis include mucosectomy?

OBJECTIVE

Debate exists as to the benefits of performing mucosectomy as part of pouch surgery for ulcerative colitis (UC) and familial adenomatous polyposis (FAP). Whilst mucosectomy results in a more complete removal of diseased mucosa, this benefit may be at the price of poorer function. We examined these issues.

METHOD

Using Medline, Embase, Ovid and Cochrane database searches papers were identified relating to the outcome following pouch surgery with and without mucosectomy. Potential reasons for functional problems were investigated, as were rates of 'cuffitis', dysplasia, polyposis and cancer in the ileal pouch and anal canal.

RESULTS

The available evidence suggests that performing a mucosectomy leads to a worse functional outcome. Meta-analysis suggested that nighttime seepage of stool and resting and squeeze pressure were worse after mucosectomy. The most likely reason for functional impairment following pouch surgery was the degree of anal manipulation. Mucosectomy does seem to confer benefit in terms of disease control but this benefit does not reach statistical significance.

CONCLUSION

Stapled anastomosis avoiding mucosectomy is the approach of choice for ileal pouch anal anastomosis because this leads to superior functional outcome. Performing mucosectomy results in some clinical benefits in terms of lower rates of inflammation and dysplasia in the retained mucosa in UC patients and lower rates of cuff polyposis in FAP patients. However, on the basis of available evidence mucosectomy is only indicated in those cases where the patient is at a high risk of disease in the retained rectal cuff.

Risk of dysplasia and adenocarcinoma following restorative proctocolectomy for ulcerative colitis

OBJECTIVE

Restorative proctocolectomy (RPC) with or without mucosectomy is the treatment of choice for most patients with ulcerative colitis (UC) requiring surgery. The ileal mucosa in the reservoir and the anorectal columnar epithelium below the ileo-anal anastomosis are at risk of neoplastic transformation.

METHOD

The literature has been reviewed to identify patients developing this complication and an attempt has been made to develop a rational follow-up policy based on the data available.

RESULTS

Dysplasia in the ileal reservoir is rare. It is associated with histological type C changes, sclerosing cholangitis and unremitting pouchitis in the ileal mucosa and to the presence of sclerosing cholangitis. Nine patients who have developed adenocarcinoma in the residual anorectal mucosa and seven in the reservoir have been reported in the literature. A further hitherto unreported patient treated by the authors brings the total to 17 patients. Twelve of these had histopathological data on either dysplasia or carcinoma in the original operative specimen. The time intervals from the onset of UC and from the RPC to the development of cancer were 120-528 (median 246) and 16-216 (median 60) months respectively. Cancer appeared to be related to the duration of disease rather than to the interval from RPC. In all the reported patients the interval from the onset of UC was 10 years.

CONCLUSION

Based on these data a surveillance programme should begin at 10 years from the onset of disease. Patients with dysplasia or carcinoma in the original specimen, those with type C ileal mucosal changes and patients with sclerosing cholangitis should be selected for surveillance. This will involve multiple biopsies of the ileal reservoir and the anorectal mucosa below the ileo-anal anastomosis.

Restorative proctocolectomy and ileal pouch-anal anastomosis for familial adenomatous polyposis revisited

Since restorative proctocolectomy (RPC) with ileal-pouch anal anastomosis (IPAA) removes the entire diseased mucosa, it has become firmly established as the standard operative procedure of choice for familial adenomatous polyposis (FAP). Many technical controversies still persist, such as mesenteric lengthening techniques, close rectal wall proctectomy, endoanal mucosectomy vs. double stapled anastomosis, loop ileostomy omission and a laparoscopic approach. Despite the complexity of the operation, IPAA is safe (mortality: 0.5-1%), it carries an acceptable risk of non-life-threatening complications (10-25%), and it achieves good long-term functional outcome with excellent patient satisfaction (over 95%). In contrast to the high incidence in patients operated for ulcerative colitis (UC) (15-20%), the occurrence of pouchitis after IPAA seems to be rare in FAP patients (0-11%). Even after IPAA, FAP patients are still at risk of developing adenomas (and occasional adenocarcinomas), either in the anal canal (10-31%) or in the ileal pouch itself (8-62%), thus requiring lifelong endoscopic monitoring. IPAA operation does not jeopardise pregnancy and childbirth, but it does impair female fecundity and has a low risk of impairment of erection and ejaculation in young males. The latter can almost completely be avoided by a careful "close rectal wall" proctectomy technique. Some argue that low risk patients (e.g. <5 rectal polyps) can be identified where ileorectal anastomosis (IRA) might be reasonable. We feel that the risk of rectal cancer after IRA means that IPAA should be recommended for the vast majority of FAP patients. We accept that in some very selected cases, based on clinical and genetics data (and perhaps influenced by patient choice regarding female fecundity), a stepwise surgical strategy with a primary IPA followed at a later age by a secondary proctectomy with IPAA could be proposed.

Development of two cancers in the same patient after ileorectal and ileal pouch anal anastomosis for familial adenomatous polyposis

OBJECTIVE

To report a case of a patient with familial adenomatous polyposis.

CLINICAL PRESENTATION AND INTERVENTION

A 36-year-old male patient who suffered from rectal bleeding was treated with colectomy and ileorectal anastomosis for familial adenomatous polyposis (FAP) in 1974. After 19 years, in situ adenocarcinoma was detected in the rectal stump. Completion proctectomy, mucosectomy, and hand-sewn ileal pouch anal anastomosis with protective ileostomy were performed. In 2002, a metachronous cancer was detected at the anastomosis and abdominoperineal resection of the pouch and end ileostomy were performed. Later on, the perineum was excised locally because of cancer recurrence.

CONCLUSION

This case shows that lifetime surveillance of the FAP patients after surgery is crucial.

Ileostomy carcinomas a review: the latent risk after colectomy for ulcerative colitis and familial adenomatous polyposis

BACKGROUND

Ileostomy carcinoma after colectomy for ulcerative colitis and familial adenomatous polyposis is rare.

METHODS

Forty-three case reports from the literature and a case of ours are reviewed.

RESULTS

The risk of malignancy following ileostomy formation appears to be increased compared to the very low incidence of primary small bowel carcinoma. Chronic physical or chemical irritation of the stoma may predispose the ileal mucosa to colonic metaplasia with subsequent adenoma formation, dysplasia and invasive malignant change. This is particularly so where ileostomies are fashioned for familial adenomatous polyposis and ulcerative colitis.

CONCLUSION

Routine surveillance of patients who have had an ileostomy for 15 years or longer may lead to earlier detection of this complication.

Ileoanal pouch neoplasia in familial adenomatous polyposis: an underestimated threat

PURPOSE

Ileal pouch-anal anastomosis is one of the two main options available for the surgical treatment of patients with familial adenomatous polyposis. Its main advantage is the minimal risk of rectal cancer but a possible Achilles heel is the recurrence of epithelial neoplasia at the ileal pouch-anal anastomosis and within the ileal pouch. The significance of ileoanal anastomotic and ileal pouch adenomas is not yet fully appreciated, and there is a false sense of security about this operation. The consequences of worsening pouch polyposis are serious in that endoscopic treatment is unlikely to be an effective way of controlling it. This study has been done to alert those caring for patients with familial adenomatous polyposis to the looming danger of pouch polyposis and to suggest ways to deal with it.

METHODS

Studies reporting ileoanal pouch adenomas, ileal pouch-anal anastomotic cancers, and ileal pouch cancers in patients with familial adenomatous polyposis were reviewed. Reports of adenomas in Kock pouches and in Brooke ileostomies in the setting of familial adenomatous polyposis were included. The primary end points of the study were the time between pouch construction and the diagnosis of neoplasia, the age of the patients at the diagnosis of neoplasia, and the severity of the neoplasia.

RESULTS

There were 18 studies reporting pouch neoplasia, 15 with adenomas, and 3 with cancer. Ten were case reports, five were retrospective studies, and three were prospective studies. All three prospective studies showed that the incidence of pouch adenomas increases with time of follow-up and that the severity of the polyposis varies. The median time from pouch construction to diagnosis of pouch adenomas was 4.7 years and the range was 0.5 to 12 years. There were six studies reporting eight patients with cancer at the ileal pouch-anal anastomosis, diagnosed a median of 8 years after pouch construction (range, 3-20 years). One-half of the cancers were locally advanced (T4) and one-half were not (T1 or T2). One-half followed stapled anastomosis and one-half were after mucosectomy. There were eight case reports of cancer described in an ileostomy in patients with familial adenomatous polyposis. The median time from ileostomy construction to the ileostomy cancers was 25 (range, 9-40) years.

DISCUSSION

The combination of fecal stasis, adenomatous epithelium, and a germline APC mutation is a potent recipe for epithelial neoplasia. There is increasing evidence that this happens in an ileostomy but that the process is much faster in an ileal pouch. Endoscopic treatment of ileal adenomas is likely to be difficult, reducing the options for their control to excising the entire pouch or chemoprevention.

Adenocarcinoma after ileoanal anastomosis for familial adenomatous polyposis: review of risk factors and current surveillance apropos of a case

Restorative proctocolectomy has become the most common surgical option for familial adenomatous polyposis (FAP) patients, based on the premise that it provides good functional results and reduces colorectal cancer risk. But several adenomas may develop in the pouch mucosa over the years, and even cancer at the anastomosis or in the pouch mucosa has been reported rarely. This article aims to describe a case of pouch cancer after restorative proctocolectomy for FAP, reviewing the possible causes of this unfortunate outcome. A 40-year-old man started presenting with fecal blood loss 12 years after restorative proctocolectomy with mucosectomy and hand-sewn anastomosis for FAP. Proctologic examination revealed an elevated mass 3 cm from the anal margin, which biopsy determined to be a mucinous adenocarcinoma. The patient underwent pouch excision and terminal ileostomy. Histologic analysis showed a 2.2 cm mucinous adenocarcinoma between the ileal and anal mucosa (T2N0Mx) and multiple tubular microadenomas in the ileal pouch. The present case and the data presented here suggest that restorative proctocolectomy is not a "cancer-free" alternative to ileorectal anastomosis, because it does not remove the risk of metachronous intestinal neoplasia. Although the long-term risk of malignancy is not known, lifelong follow-up seems to be necessary after restorative proctocolectomy. Current recommendations for pouch surveillance are presented.

Pouch reconstruction in the pelvis

ILEAL POUCH RECONSTRUCTION: Proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the procedure of choice in mucosal ulcerative colitis (MUC) and familial adenomatous polyposis (FAP). Because the disease is cured by surgical resection, functional results, pouch survival prognosis, and disease or dysplasia control are the major determinants of success. There is controversy as to whether the IPAA should be handsewn with mucosectomy or stapled, preserving the mucosa of the anal transitional zone. Crohn's disease is a contraindication for IPAA, but long-term outcome after IPAA is similar to that for MUC in patients with indeterminate colitis who do not develop Crohn's disease. As development of dysplasia and cancer in the ileal pouch have been reported, a standardized surveillance program is mandatory in cases of MUC, FAP, and chronic pouchitis. COLONIC POUCH RECONSTRUCTION: Construction of a colonic pouch is a widely accepted technique to improve functional outcome after low or intersphincteric resection for rectal cancer. Several randomized studies comparing colo-pouch-anal anastomosis (CPA) with straight coloanal anastomosis (CAA) have found the pouch functionally superior. Most controlled studies cover only 1-year follow-up, but randomized studies with 2-year follow-up show similar functional results of CPA and CAA. Evacuation difficulty as initially observed was related to pouch size, and the results with smaller pouches (5-6 cm) are more favorable, showing adequate reservoir function without compromising neorectal evacuation. The transverse coloplasty pouch may offer several advantages to J-pouch reconstruction. Current series question whether the neorectal reservoir is the physiological key of the pouch, but rather the decreased motility. The major advantage reported with colonic pouch reconstruction is the lower incidence of anastomotic complications.

Dysplasia in the ileoanal pouch

Formation of an ileo-anal pouch is an accepted technique following colectomy in the surgical management of ulcerative colitis (UC) and familial adenomatous polyposis (FAP). The configuration of pouches and anastomotic techniques has varied over the last two decades. The increased use of stapling devices in formation of the pouch-anal anastomosis avoids the need for endoanal mucosal stripping and may contribute to improved functional results, but leaves a 'columnar cuff' of residual rectal mucosa in situ. Concerns regarding the long-term safety of the ileo-anal pouch have been raised by reports of the occurrence of dysplasia in the pouch mucosa and 15 cases of adenocarcinoma. In UC, persistence of underlying disease in the residual rectal mucosa, anal transition zone and columnar cuff provides the site for development of dysplasia and malignancy. Pouchitis is unlikely to be a major cause of dysplasia or malignancy, as long-term follow-up of patients with Koch pouches has demonstrated. In FAP, any persistent rectal mucosa and mucosa of the small intestine is at risk of adenomatous dysplasia due to the genetic alterations causing the disease. Long-term surveillance should focus on all FAP pouch patients, and in UC patients should be directed towards the diagnosis of residual rectal mucosa in the area distal to the pouch anastomosis. Specialist histopathological opinion is essential in the diagnosis of dysplasia in the ileo-anal pouch.