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Adenomatous polyps develop commonly in the ileal pouch of patients with familial adenomatous polyposis.

PURPOSE: The aim of this study was to establish the prevalence of adenomatous polyps in the ileal pouch of patients with familial adenomatous polyposis. METHOD: Forty-three patients who had an ileal pouch for familial adenomatous polyposis were invited to have a careful endoscopic examination of their pouch, including dye spraying. The number of polyps was recorded, and up to ten were biopsied. In addition, four random biopsy specimens were taken from the proximal and four from the distal pouch. RESULTS: Thirty-three patients with a median age of 36 (range, 14-63) years who had a pouch (5 Kock and 28 pelvic) for a median of 7 (range, 1-19) years accepted the invitation. Twenty-one patients (64 percent) had endoscopically identified polyps, the number of polyps ranging from 1 to 100 (median, 10) and varying in size from 1 to 3 mm. Fourteen patients (42 percent) had adenomatous polyps and 4 of these also had microadenomas on random biopsies. Nine of the 14 patients with adenomas also had lymphoid polyps. Seven patients had lymphoid polyps only and two of these patients had a microadenoma on random biopsy. Four of 12 patients with no visible polyps had microadenomas in their random biopsies. The presence of adenomatous polyps (Pearson's correlation; P < 0.01) increased with the age of the pouch. In total, 20 of 33 (60 percent) patients had adenomas and or microadenomas. CONCLUSION: Adenomatous polyps occur frequently in ileal pouches. These findings are of concern, and therefore, regular surveillance seems warranted until the natural history of these adenomatous polyps is determined.

Adenomatous Polyposis Coli↗

Desmoid disease in patients with familial adenomatous polyposis.

PURPOSE: The aim of this retrospective study was to review the clinical features, and surgical and medical management of patients with familial adenomatous polyposis-associated desmoid tumors. METHODS: From 1980 to 1997, 97 of 780 patients with familial adenomatous polyposis developed desmoid disease. Clinical and demographic data; operative notes; and histologic, radiologic, and follow-up reports were retrieved from patients' medical records. Risk factors for desmoid disease, such as prior surgery, age at desmoid tumor diagnosis, pregnancy, and family history were sought. The outcome after noncytotoxic and cytotoxic therapy was evaluated with respect to improvement of symptoms. RESULTS: There were 38 males with a mean age of 32.1 years and 59 females with a mean age of 29.1 years. A family history of desmoid tumors was found in 41 patients (42 percent), and a history of pregnancy was documented in 33 females (56 percent). The most common clinical presentation was small-bowel obstruction (58 percent). One-half of the desmoids were located in the mesentery, and 32 percent were located in the mesentery and the abdominal wall. Desmoids developed after colectomy in 77 cases (80 percent), after a mean time of 4.6 years. Partial resection of desmoid tumor was performed in 46 patients (47 percent), resection of extra-abdominal desmoid tumors was performed in 17 cases (17 percent), and biopsy only was performed in 34 patients (35 percent). Postoperative morbidity was 23 percent after desmoid tumor resection. Eight patients (8 percent) died of their intra-abdominal desmoid. Mean follow-up time was 5.3 years. Sulindac, tamoxifen, or toremifene therapy was able to alleviate symptoms in only 4 of 31 patients. Symptomatic improvement was noted after chemotherapy in six of ten patients with extremely complex desmoids. CONCLUSION: Desmoid disease was found in 12.4 percent of our patients with familial adenomatous polyposis. In view of the high rate of morbidity, indication for surgery should be limited mainly to acute or chronic small-bowel obstruction, because resection triggers a high recurrence rate. Noncytotoxic therapy was not effective for progressive desmoid tumors, whereas chemotherapy was effective in aggressive cases of intra-abdominal desmoid tumors.

Adenomatous Polyposis Coli↗

Primary rectal lymphoma and malignant lymphomatous polyposis. Two cases illustrating current methods in diagnosis and management.

Two cases of colorectal lymphoma are presented. Preoperative histologic diagnosis is difficult and examination of the fresh specimen using immunocytochemical and gene rearrangement techniques are necessary to establish the precise nature of the lesion. Surgical excision is the mainstay of treatment for localized lymphoma of the colorectum and chemotherapy for malignant lymphomatous polyposis.

Aged↗

Physiology of ileoanal anastomosis with ileal reservoir for ulcerative colitis and adenomatosis coli.

A physiologic and metabolic assessment was carried out on eight patients six months after total proctocolectomy with ileal reservoir for ulcerative colitis and familial adenomatosis coli. All patients were continent and able to defecate spontaneously, stool frequency ranging from two to five per 24 hours. Anal sphincter resting pressures (35 +/- 14 mmHg) and squeeze pressures (88 +/- 24.2 mmHg) were similar to those of a healthy population, with the exception of one patient's complaint of nocturnal mucous leakage per anus. Biopsies of the ileal mucosa of the reservoirs showed a mild inflammation in seven patients; in one a subtotal villous atrophy (plus glandular pattern) was found. Anthropometric measurements, lymphocyte counts, hemoglobin, albumin, transferrin, iron, B12, and folate were normal in all. In the majority of patients there was no evidence of bacterial overgrowth. Vitamin B12 absorption was reduced slightly in only one patient. Lipid absorption (as judged by the 14C-Triolein breath test) was abnormal in three patients. Fecal clearance of alpha 1 antitrypsin as protein losses index was abnormal in three patients. Bile acid malabsorption was the most important ileal dysfunction observed in the patients.

Adenomatous Polyposis Coli↗

Is routine pouch surveillance for dysplasia indicated for ileoanal pouches?

PURPOSE: Isolated accounts of neoplastic pouch transformation suggest the need to perform routine ileoanal pouch surveillance with biopsy. These reports imply a model of dysplasia to cancer transformation of the pouch mucosa. More recent reports studying "high risk" ulcerative colitis patients concluded that the development of pouch dysplasia is indeed a rare event. This study was designed to evaluate our institutional incidence of dysplasia in ileoanal pouch during long-term follow-up. METHODS: A prospective database of all patients undergoing ileoanal pouch construction (n = 767) was queried for all patients undergoing pouch biopsy between 1983 and 2001. All patients with ulcerative colitis who underwent pouch biopsy were included. This excluded patients with Crohn's disease, indeterminate colitis, and familial adenomatous polyposis. Pathology reports were reviewed for histologic evidence of inflammation, atypia, metaplasia, dysplasia, or cancer. Patient age at biopsy, pouch age at time of biopsy, and pathology were analyzed. RESULTS: The ileoanal pouches of 160 patients were surveyed with biopsies a total of 222 times. The average length of follow-up from pouch construction to time of surveillance and biopsy was 8.4 +/- 4.6 years. There were 83 patients (52 percent) whose pouches were older than 10 years (mean, 12.7 +/- 2) at time of surveillance. With over 1,800 pouch-years of surveillance, only 1 patient had focal, low-grade dysplasia in the pouch. This patient demonstrated no evidence of dysplasia on further surveillance. CONCLUSION: Even with long-term follow-up of ileoanal pouch patients, there is little evidence to support routine biopsy of the ileal mucosa in ulcerative colitis patients.

Adenomatous Polyposis Coli↗

CT colonography (virtual colonoscopy) for the detection of colorectal polyps and neoplasms. current status and future developments.

Computed tomography colonography (CTC) is a new, rapidly developing non-invasive CT technique used to detect colonic polyps and cancers. It employs two- (2D) and three-dimensional (3D) images of the colon in order to display neoplastic lesions. Clinical trials demonstrate promising results for the detection of polyps and cancers greater than or equal to 10 mm in size. Our purpose is to describe the technique of CT colonography, review recent published trials of CT colonography, and elucidate current clinical applications. Continuing technical innovations such as multidetector CT, computer-aided diagnosis, new image display techniques and faecal tagging promise to improve the performance and patient acceptance of CT colonography in the future.

Adenomatous Polyposis Coli↗

Pathology of colorectal cancer.

The earliest phases of colorectal tumourigenesis initiate in the normal mucosa, with a generalised disorder of cell replication, and with the appearance of clusters of enlarged crypts (aberrant crypts) showing proliferative, biochemical and biomolecular abnormalities. The large majority of colorectal malignancies develop from adenomatous polyps. These can be defined as well demarcated masses of epithelial dysplasia, with uncontrolled crypt cell division. An adenoma can be considered malignant when neoplastic cells pass through the muscularis mucosae and infiltrate the submucosa. Definitions like "carcinoma in situ" or "intramucosal carcinoma" should be abandoned, since they lead to confusion. Although several lines of evidence indicate that carcinomas usually originate from pre-existing adenomas, this does not imply that all polyps undergo malignant changes, and does not exclude "de novo" carcinogenesis. Besides adenomas, other types of polypoid lesions include hyperplastic polyps (showing elongated crypts often with cystic dilatation), serrated adenomas (with a serrated glandular pattern], flat adenomas (flat lesions which are difficult to detect in routine lower endoscopy, but may possess malignant potential), hamartomatous polyps (which show a complex branching pattern of smooth muscle supporting normal lamina propria and glands), and inflammatory polyps. Colorectal carcinomas are one of the most frequent neoplasms in Western society; the macroscopic appearance of these lesions may be that of a polypoid vegetating mass or of a flat infiltrating lesion. Most of these tumours are adenocarcinomas (96%), that, in some cases, show a mucinous component. More rare malignancies of the large bowel include signet-ring cell carcinoma, squamous carcinoma, undifferentiated neoplasms and medullary type adenocarcinoma (solid carcinoma with minimal glandular differentiation or slight cellular pleomorphism). Colorectal carcinoma can be graded into well, moderately and poorly differentiated lesions; there is little evidence, however, that grading may be of help in evaluating prognosis of affected patients. In conclusion, colorectal tumours cover a wide range of premalignant and malignant lesions, many of which can easily be removed at endoscopy. It follows that colorectal neoplasms might be prevented by interfering with the various steps of carcinogenesis, which begins with uncontrolled epithelial cell replication, continues with the formation of adenomas of various dimensions, and eventually evolves into malignancy.

Adenomatous Polyposis Coli↗

Metabolic consequences of total colectomy.

Colectomy is performed for inflammatory bowel disease, familial polyposis syndrome and colorectal carcinoma. Surgical procedures are ileostomy with or without pouch, ileorectal anastomosis or ileal pouch-anal anastomosis. One of the major functions of the intact large intestine is to absorb water and electrolytes. After colectomy, as much as 400-1000 ml of nearly isotonic ileostomy fluid may be excreted, resulting in a chronic salt and water depletion. This is compensated for by an activation of the renin-angiotensin-aldosterone system. Reduced urine volumes may cause kidney stones. Both dehydration and renal sodium retention are probably less frequent in patients with ileal pouch-anal anastomosis. Absorption of nutrients in general is not impaired by colectomy. The large intestine salvages energy from malabsorbed organic matter through absorption of the short-chain fatty acids produced in bacterial fermentation. In ileostomy patients, fermentation is negligible, which leads to a significant loss of energy in the ileostomy fluid. Pouches are colonized by a bacterial flora similar to colonic bacteria. In these patients conservation of energy from malabsorbed substrate may be similar to healthy subjects. Resection of ileum and bacterial colonization may lead to malabsorption of vitamin B12 and bile acids. The latter may cause increased incidence of biliary cholesterol stones. Pouchitis is a frequent problem which may be caused by a deficiency of short-chain fatty acids and glutamine in the pouch contents. It is concluded that although the colon is not essential as a digestive organ in man, colectomy results in a number of metabolic changes. The ileal pouch-anal anastomosis may in part substitute for the functions of the large intestine.

Bile Acids and Salts↗

Sulindac in familial adenomatous polyposis: evaluation by nuclear morphometry.

OBJECTIVE: To find out if nuclear morphometry is a useful indicator of prognosis in patients with familial adenomatous polyposis (FAP) before and after treatment with sulindac. DESIGN: Open study. SETTING: Teaching hospital, Spain. SUBJECTS: 29 patients (17 women and 12 men) with FAP who had been treated by colectomy. There were two control groups: 17 people with healthy rectal mucosa and 10 patients with colorectal cancer. INTERVENTIONS: The 29 patients with FAP were treated with sulindac 150 mg orally twice daily for 6 months. MAIN OUTCOME MEASURES: Results of histological examination of biopsy specimens and nuclear morphometry. RESULTS: Before treatment, all patients with FAP had nuclei of cells in the rectal mucosa that were intermediate in size between those in healthy mucosa (small nuclei) and those in cancer (large nuclei). After 6 months' treatment with sulindac the patients with FAP no longer had any polyps and the size of the nuclei was similar to those in healthy mucosa. Only 1 patient failed to respond, and in this patient one of the polyps subsequently became malignant. CONCLUSIONS: Nuclear morphometry may be useful in identifying patients with FAP who are at high risk of malignant degeneration.

Adenomatous Polyposis Coli↗

Colorectal polyps in Cowden's disease (multiple hamartoma syndrome).

Colorectal polyps are described in five patients with Cowden's disease. A brother-sister kindred and two unrelated patients had multiple colonic polyps 0.1-0.4 cm in diameter. Microscopical examination of seven polyps removed from these four patients showed distinctive lesions which were probably hamartomatous, and characterized by disorganization and proliferation of the muscularis mucosae with minimally abnormal overlying mucosa. The fifth patient had a solitary 2-cm epitheloid leiomyoma resected from the rectum. Review of all cases of Cowden's disease in the English literature suggests that gastrointestinal polyposis may be a frequent finding if it is specifically searched for. It does not appear that the previously reported association of Cowden's disease with gastrointestinal cancer is valid. The discovery of multiple colonic polyps 0.1-0.4 cm is diameter with a rectosigmoid distribution and a hamartomatous microscopical appearance is characteristic of Cowden's disease. Cowden's disease should be included in the differential diagnosis of gastrointestinal polyposis states.

Adult↗

Expression of cytokeratins in normal and neoplastic colonic epithelial cells. Implications for cellular differentiation and carcinogenesis.

Cells of the normal colonic mucosa express several types of cytokeratins, the characteristic intermediate filament proteins of epithelial cells. An immunohistochemical study was designed to examine the expression of two distinct groups of cytokeratins, recognized by monoclonal antibodies AE1 and AE3, in the colonic mucosa and to compare the findings with those obtained with a large number of polypoid lesions (adenomatous and hyperplastic) and carcinomas of the colon. AE1 and AE3 immunostaining was found in the surface epithelium and upper portions of the crypts of Lieberkühn (functional zone) of normal colonic mucosa, whereas the lower portions of the crypts (proliferative compartment) were unreactive with both AE1 and AE3. Polypoid lesions of the colonic mucosa can be placed into two categories based on their patterns of cytokeratin expression. Solitary tubular adenomas and hyperplastic polyps are composed of AE1 and AE3 nonexpressing cells with only few, patchy areas of AE1 and AE3 expressing cells present within glands and in the surface epithelium. In contrast, villous adenomas show strong AE1 and AE3 reactivity throughout the glands. Furthermore, tubular and villous adenomas, and even histologically normal mucosa in patients with familial polyposis, show AE1/AE3 expression throughout the glands and surface epithelium. Colonic carcinomas show a predominance of AE1/AE3 expressing cells. Thus, cytokeratins recognized by monoclonal antibodies AE1 and AE3 represent molecular markers of cellular maturation in the normal colonic mucosa, that are expressed in colonic carcinomas and, in addition, serve as markers that distinguish colonic mucosa and adenomas with a high risk for development of cancers from those with a lower risk.

Adenocarcinoma↗

Preservation of anorectal continence following total colectomy.

The search for continence in the surgical management of ulcerative colitis has resulted in the evolution of a method that has yielded gratifying results in the last 18 patients. The disease process is removed; all patients are continent; they have no postoperative perineal excoriation; the frequency of stools is not excessive and the patients are returning to work or to school within three weeks following ileostomy closure. Their ages were eight to 52 years. The procedure consists of a total of colectomy with mucosal proctectomy, ileoanal anastomosis and construction of a terminal ileal, pelvic reservoir. A proximal ileostomy diverts the fecal stream until healing is complete. The authors are now recommending the operation be considered for patients of all ages who require surgery for chronic ulcerative colitis as well as polyposis.

Adolescent↗

Proliferation in human gastrointestinal epithelium using bromodeoxyuridine in vivo: data for different sites, proximity to a tumour, and polyposis coli.

The distribution of DNA synthesising cells in the crypts of the epithelium in human small and large bowel after injection of bromodeoxyuridine into patients has been studied in relation to the position of the cells in the crypt using immunohistochemistry. Different sites of normal epithelium have been studied. The ileum has a shorter crypt and a very significantly smaller total cell population size. However, it has similar peak labelling index (LI) values to the colon, while the rectum has a lower peak LI value. The mean position of the label occurs at the 17th cell position in the ileum and at about the 22nd position in both the colon and rectum. The overall mean LI is significantly higher in the ileum at 17.8%, intermediate in the colon at 10.3%, and lowest in the rectum at 8.5%. There is thus an inverse relation between the likelihood of developing a tumour and the rate of cell proliferation as measured by the LI. Assuming a value of 8.6 hours for the duration of S, the data suggest that the cell cycle time in the mid crypt region is about 30 hours for the ileum and colon and about 37 hours for the rectum. Samples taken adjacent (within 1 cm) to a tumour show a general dampening of proliferative activity at all cell positions compared with samples taken more than 5 cm from a tumour. This is illustrated by the average LI, which is about 5.4% in the colon adjacent to a tumour compared with 10% distant; comparable values for the rectum are 4.6% and 8.5%. Samples taken from two patients with polyposis coli show distributions with a significant difference in skewness compared with normal colon and a general shifting of the distribution to the right, that is to higher cell positions. There is a significant increase in the mean cell position and the position of the peak LI in the polyposis coli samples.

Adenomatous Polyposis Coli↗

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