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[Magnetic closure for ileostomy (author's transl)].

The Maclet magnetic stoma seal already used by the authors for colostomies was applied to the closure of permanent terminal ileostomies. A reservoir is constructed upstreams of the closure with the last loop of ileum, so that the faeces accumulate and can be evacuated by intermittence. Patients empty the reservoir by removing the cap which blocks the intestinal lumen and introducing a probe into it. The technique was used on 2 patients who had undergone total proctocolectomy for familial polyposis of the colon. One patient has now been followed up for 3 years and the other for 6 months. The perfect continence obtained by this method favourably compares with Kock's continent ileostomy.

Humans↗

Overexpression of phospholipase C-gamma 1 in familial adenomatous polyposis.

Phosphoinositide-specific phospholipase C (PLC) isozymes occupy a central role in the signal transduction system by regulating various cellular processes including proliferation and differentiation. In the present study, we examined the contents of PLCs in colorectal adenomas, carcinomas, and normal mucosa obtained from 4 familial adenomatous polyposis patients to find out whether this enzyme plays any role in the pathogenesis of adenomas and/or carcinomas in familial adenomatous polyposis. Radioimmunoassay and immunoblot analysis revealed that in contrast to little difference in PLC-beta 1 and PLC-delta 1 content, a considerably higher level of PLC-gamma 1 was detected in 3 of 4 cases for adenoma and in all cases for carcinoma as compared to normal mucosa. The level of PLC-gamma 1 expression increased from normal mucosa to adenoma, and finally to carcinoma progressively. Immunohistochemical findings also confirmed this observation. Likewise, activity of PLC-gamma 1 was considerably higher in adenomas and carcinomas than in normal mucosa. These results suggest that PLC-gamma 1-mediated signal transduction may play a significant role in the progression of colorectal tumors in patients with familial adenomatous polyposis.

Adenoma↗

[Correlation between hyperplastic and adenomatous polyps of the colon].

PROBLEM: Although hyperplastic polyps are considered to be non-neoplastic, they nevertheless have a number of characteristics in common with adenomatous polyps. STUDY DESIGN: Since hyperplastic polyps and adenomas frequently occur together, the question arises as to whether hyperplastic polyps, found for example during sigmoidoscopy, might not be an indicator of possibly neoplastic polyps in the more proximal part of the bowel. In a retrospective analysis of first-time total colonoscopies in 685 patients, we investigated the relationship between hyperplastic and adenomatous polyps. RESULTS: Twenty-one patients proved to have only hyperplastic polyps in the rectosigmoid, while 12 of these patients (11.8%) also had adenomatous polyps in the more proximal parts of the colon. In contrast, 30.8% of the patients (n = 109) with rectosigmoidal adenomas also had adenomas in the more proximal colon. Irrespective of histology, as the size of rectosigmoidal polyps increased, so did the percentage of patients with adenomas in the proximal colon--from 22.4% in the case of small polyps not exceeding 5 mm in diameter to more than 31.2% in the case of polyps larger than 5 mm in diameter. When both hyperplastic and adenomatous polyps appeared together, hyperplastic polyps were found in larger numbers in the same or anatomically adjacent segment of the colon. CONCLUSION: The results of this study suggest that the presence of hyperplastic polyps in the rectosigmoid is not associated with an increase in the incidence of proximal adenomas, while rectosigmoidal adenomas must be considered indicators of adenomas in the more proximal parts of the bowel.

Adenomatous Polyposis Coli↗

Widespread microsatellite instability occurs infrequently in adenocarcinoma of the gastric cardia.

Heredity non-polyposis colorectal cancer (HNPCC) is associated with an increased predisposition to colorectal cancer and extra-colonic cancers of the gastro-intestinal, urological and female reproductive tracts. These tumours are characterised by an underlying defect in DNA mismatch repair and exhibit numerous replication errors throughout the genome (RER+ phenotype). HNPCC-associated gastric tumours, and a subset of sporadic, distally-located gastric tumours exhibit this RER+ phenotype. It is recognised that proximal and distal gastric tumours exhibit distinct epidemiological features. In this study we investigated the occurrence of microsatellite instability in a series of 38 primary gastric adenocarcinomas, arising in the proximal stomach. A total of 138 microsatellite markers, comprising mainly dinucleotide and tetranucleotide repeat units and covering all autosomal arms, excluding acrocentric arms, were analysed. One tumour demonstrated somatic microsatellite alterations at 62% (26 of 42) of loci tested. A further 32 tumours demonstrated levels of microsatellite instability ranging from 0.8% (1 of 28)-11.4% (15 of 132) of loci tested. Five tumours demonstrated no microsatellite alterations at any of the loci tested. These findings suggest that a high percentage of proximal gastric carcinomas exhibit a low level of microsatellite alterations at dinucleotide and tetranucleotide repeat loci. However, ubiquitous somatic alterations at these loci, characteristic of HNPCC-associated tumours, occur in a relatively small proportion of tumours.

Adenocarcinoma↗

Fecal and rectal mucosal diacylglycerol concentrations and epithelial proliferative kinetics.

Fecal diacylglycerol (DAG) concentrations have been suggested as biomarkers for colonic neoplasia because of their potential to be absorbed in the colon and to stimulate epithelial cell proliferation. The interrelationships among nutrient intake, fecal and mucosal DAG, and colonic proliferative markers have not previously been studied. We designed a pilot study to evaluate the feasibility of evaluating these interrelationships in 12 volunteers who had a history of colonic adenomatous polyposis. Total mucosal DAG concentrations were not related to fecal DAG concentrations, but mucosal DAG correlated inversely with the whole crypt labeling index. Dietary intake did not alter fecal DAG concentrations. However, the percentage of calories from dietary fat correlated positively with the whole crypt labeling index. Fiber and calcium intake showed a positive correlation with the labeling index in the upper 40% of the crypt. The present pilot study failed to demonstrate a correlation between dietary components and fecal and total mucosal DAG. Additional studies relating fecal DAG with mucosal proliferation will require the evaluation of DAG concentrations in subcellular compartments of mucosal cells and/or measurement of fecal DAG fatty acid composition.

Adenomatous Polyposis Coli↗

Role of upper gastrointestinal surveillance in patients with familial adenomatous polyposis.

Familial adenomatous polyposis (FAP) is an inherited autosomal-dominant disease in which hundreds and thousands of adenomas with malignant potential are found throughout the colon and rectum. An increased risk for benign and malignant upper gastrointestinal neoplasia has long been recognized in patients with FAP. In this article, the authors report their findings from a study of 35 registered patients to assess the prevalence, anatomic distribution, depth of invasion, and natural history of upper gastrointestinal tumors in patients with FAP.

Adenoma↗

[Serrated neoplasia of the gastro-intestinal tract].

Serrated neoplasia of the gastro-intestinal tract have peculiar microscopic and molecular features that are still incompletely described. Some serrated polyps seem to be involved in a new carcinogenic pathway in the colon: the serrated neoplasia pathway, with hypermethylation of the cytosine-guanine dinucleotides, located in the promoter of some genes such as h-MLH1, BRAF and MGMT. The natural history of the serrated polyps and their risk for progression to malignancy are still unclear. There is no official guideline for the management of serrated polyps. The aim of this article is to describe the epidemiological, morphological, immunohistochemical and molecular characteristics of the serrated neoplasia of the gastrointestinal tract: hyperplastic polyps, "traditional" serrated adenomas, mixed hyperplastic and adenomatous polyps, sessile serrated adenomas, hyperplastic polyposis and serrated adenocarcinomas.

Adenocarcinoma↗

Analysis of reciprocal congenic lines reveals the C3H/HeJ genome to be highly resistant to ApcMin intestinal tumorigenesis.

Genetic background affects polyp development in the Multiple intestinal neoplasia (Apc(Min)) mouse model. The Modifier of Min 1 (Mom1) locus accounts for approximately 50% of the variation in polyp multiplicity. We generated reciprocal congenic lines, such that the recipient C57BL/6J (B6) strain carries a donor C3H/HeJ (C3H) Mom1 allele, and the recipient C3H strain carries a donor B6 Mom1 allele. Hybrid progeny from congenic females mated to B6 Apc(Min/+) males were analyzed. A single C3H Mom1 locus on the B6 background reduced small intestinal polyp numbers by 50% and colon polyp incidence by 66% compared to their susceptible B6 Mom1(S/S)Apc(Min/+) siblings. These findings show that the C3H genome contains a resistant Mom1(R) locus. The reciprocal congenic line, which carries the susceptible B6 Mom1(S) locus on the C3H background, reduced small intestinal polyp numbers by 80% and colon polyp incidence by 95% compared to B6 Mom1(S/S)Apc(Min/+) mice. These data demonstrate that unidentified modifiers in the C3H strain can suppress intestinal polyp multiplicity in Apc(Min/+) mice, and act in the absence of a resistant Mom1(R) locus.

Adenomatous Polyposis Coli↗

Undifferentiated columnar cells in colorectal adenomas and familial adenomatous polyposis.

We have observed and defined morphometrically and histochemically groups of undifferentiated columnar cells within the surface epithelium in colorectal mucosa. They were present within both non-polypoid and polypoid mucosa in familial adenomatous polyposis, and within non-hereditary adenomatous polyps of the colon and rectum. The cells show some evidence of proliferative activity and appear similar to cells previously described in the stomach which were proposed as precursors to type 3 sulphomucin-secreting intestinal metaplasia in atrophic gastritis. To our knowledge, these observations have not been previously described. It is possible that the cells represent the cellular basis of the shift in the proliferative zone from the normal site at the crypt base to the colorectal mucosal surface, which is known to precede adenomatous polyp formation. The cells may therefore be involved in the early stages of colorectal adenoma formation.

Adenomatous Polyposis Coli↗

N-ethyl-N-nitrosourea treatment of multiple intestinal neoplasia (Min) mice: age-related effects on the formation of intestinal adenomas, cystic crypts, and epidermoid cysts.

The timing of intestinal tumor initiation in B6-Min/+ mice has been examined by treating mice at 5-35 days of age with a single i.p. injection of the direct-acting alkylating agent N-ethyl-N-nitrosourea (ENU). Treatment of Min/+ mice at 5-14 days of age resulted in a 3.8-fold increase in intestinal tumor multiplicity over untreated mice. Mice treated at 20-35 days of age showed only a 1.6-fold increase in tumor number. These results, in conjunction with examination of tumor multiplicities of untreated Min/+ mice as a function of age, suggest that the majority of intestinal tumors in Min/+ mice are initiated relatively early in life. Min/+ mice treated with ENU also showed an increase in the number of cystic intestinal crypts. However, the relationship between age at ENU treatment and cystic crypt multiplicity was distinct from that seen for intestinal adenomas. Mice treated at 5-9 days of age showed only a 1.9-fold increase in cystic crypts over untreated animals. By contrast, the increase in average cystic crypt multiplicity for mice treated at 10-35 days of age was 4.5-fold. In addition, 60% of Min/+ mice treated with ENU before 25 days of age developed epidermoid cysts, an extracolonic manifestation commonly associated with familial adenomatous polyposis in humans.

Adenoma↗

[Intestinal transplantation in adults: present situation and future prospects].

Intestinal transplantation is becoming more firmly established as a treatment for intestinal failure in patients whose home parenteral nutrition regimens have caused serious side effects. Outcomes have improved spectacularly over recent years thanks to the refinement of surgical techniques and the introduction of new immunosuppressants, and also to greater experience in anesthetic and postoperative management of intestinal transplant patients. The main causes of high morbidity and mortality continue to be sepsis and acute rejection of the graft. Both graft and patient survival have improved with the advent of the immunosuppressant regimens based on Tacrolimus, although survival rates are still far below those reported for other solid organ transplants. The first intestinal transplant performed in Spain took place in July 2002 in our hospital and the results were promising. Given this new challenge for anesthesiologists, we decided to review current trends in the perioperative management of patients receiving isolated intestinal transplants, the main complications that arise, treatment strategies, and future prospects.

Adenomatous Polyposis Coli↗

Ornithine decarboxylase as a marker for premalignancy in the stomach.

Assessment of mucosal ornithine decarboxylase (ODC) activity in the human large bowel may be of value as a marker of potential malignant risk. Its value as a marker of premalignancy in the upper gastrointestinal tract is less clear. Using a [14C]-ornithine bioassay, gastric mucosal ODC activity was measured in 32 normal subjects and 22 patients with confirmed gastric cancer. These results were compared with 47 patients at increased risk of upper gastrointestinal malignancy, (32 patients with partial gastric resection, 15 patients with familial adenomatous polyposis). Median ODC activity in normal subjects was 371 pmol/mg protein/h, (interquartile range (IQR), 230-617). There was no variation with age or sex and no relation to Helicobacter pylori status. Normal subjects had significantly lower ODC activity than patients with a gastric resection or confirmed gastric cancer, but similar to patients with familial adenomatous polyposis. Furthermore, no difference in activity was identified between patients with a gastric resection and established gastric cancer. ODC activity was, however, significantly increased in areas of gastric atrophy or intestinal metaplasia, regardless of the clinical group from which the samples were obtained. It is concluded that measurement of mucosal ODC activity does not provide additional predictive information of malignant risk in the stomach and investigation of other potential biomarkers of malignancy is warranted.

Adenomatous Polyposis Coli↗

[Polyps (single or multiple) and juvenile polyposis].

The authors underline the important aspects of juvenile familial polyposis (JFP), a disease transmitted as an autosomal dominant trait. A case of JFP characterized by the presence of hundreds of polyps in the colo-rectal intestinal tract, is analyzed. The single juvenile polyp, multiple polyps (=/>5 polyps) and the sporadic form are examined. These are mucous hamartomas which can undergo neoplastic transformation (in carcinoma in 68% of untreated cases), a behaviour similar to that of adenomatous polyps. They differ from the later due to the following features: epidemiology (earlier appearance age), anatomopathology (stroma), clinical observation (self-recovery in some cases) and genetics (10q23.3-18q21, genetic mutations in a locus different those of adenomatous polyps). It is also necessary to determine its extension by means of colonoscopy, ileoscopy, gastroscopy and small bowel barium enema. Patients' screening through construction of the genealogical family tree is fundamental. Isolation of possible degenerative aspects of the polyps through biopsy is also fundamental. Single or multiple polyps are treated endoscopically, the juvenile polyposis is treated surgically (colectomy, total colectomy). A rigorous follow-up of the patients and their family members is recommended.

Adenomatous Polyposis Coli↗

Gastrointestinal bleeding in infancy and childhood.

In summary, the causes of GI bleeding in infancy and childhood are varied, ranging from congenital and hereditary disorders to those more commonly seen in the adult population. Many causes of GI bleeding in the pediatric population are restricted to a narrow range regarding age of onset, frequently enabling the physician to narrow the differential diagnosis before proceeding with invasive investigation; however, GI bleeding may involve any portion of the intestinal tract, from mouth to anus, as in adulthood, and many causes common to the adult population also must be considered.

Adenomatous Polyposis Coli↗

COX-2 and colon cancer.

The role of cyclooxygenase-2 (COX-2) in colorectal tumorigenesis in mice was studied by Oshima et al. to determine the effects of COX-2 gene knockouts and a new COX-2 inhibitor. In the study, heterozygous Apcdelta716 knockout mice, a mouse model of human familial adenomatous polyposis (FAP), were either crossed to COX-2 gene knockout mice, or fed chow containing the COX-2-selective inhibitor. Apcdelta716 litter mates were used as positive controls, which developed 652+/-198 (SD) polyps at 10 weeks. Introduction of a COX-2 gene mutation, or feeding with the COX-2-selective inhibitor to the Apcdelta716 knockout mice, reduced the number and size of intestinal polyps dramatically. The results provide direct genetic evidence that COX-2 plays a key role in tumorigenesis, and indicate that COX-2-selective inhibitors can be a new class of therapeutic agents for colorectal polyposis and cancer.

Adenomatous Polyposis Coli↗

Continent ileoanal endorectal pull-through.

Five patients with familial polyposis coli, ages 13 through 21 yr, were given the choice of permanent reservoir-type ileostomy or ileoanal endorectal pull-through to prevent cancer of the colon. Total colectomy and an ileoanal endorectal pull-through was uniformly chosen and was performed using the principles described by Boley and Soavè. The post-operative courses were characterized by a transition from 8 to 10 liquid stools per day and up to 3 incontinent nocturnal stools, to a bowel pattern of 2 to 4 continent semi-liquid stools without nocturnal soiling by 1 mo. Defecograms at 1 mo revealed excellent sphincter function and mild reservoir dilatation of the ileum. These observations have convinced us that this is the operative management of choice for familial polyposis.

Adolescent↗

Emergent issues in the genetics of intestinal neoplasia.

Mutation of the APC gene may be a common denominator of all human colon cancer--polypoid and non-polypoid familial cancer as well as sporadic occurrences. Fearon and Vogelstein (1990) have described a series of molecular changes during the progression of human colon cancer, beginning with mutations in APC. Min is a strain of the laboratory mouse carrying a nonsense mutation in Apc, the mouse homologue of APC. The Min strain has been used to test the effect of germline alterations in certain genes identified in the progression pathway of Fearon and Vogelstein. A deficiency in DNA cytosine methylase leads to a reduction in the tumour multiplicity of Min mice contrary to the a priori expectation based on the global hypomethylation of the DNA of early colonic neoplasms. Alterations in Kras had no perceptible effect on the tumour multiplicity of Min mice but may not have been successfully directed to the proliferative cell population. Constitutional mutation of p53 did not influence the multiplicity or histopathology of early Min induced intestinal tumours. The cause and effect analysis of the genetics of colon cancer is clearly in an early phase. An unlinked genetic factor interacting with Min in controlling intestinal tumour multiplicity is Mom1. A central goal for the near future is to identify the Mom1 gene product and to identify other loci that can interact with the Min mutation and affect tumour multiplicity or progression. Mouse chimaeras will permit an analysis of the clonality and cell autonomy of Min induced neoplasms and also of the action of Mom1. The results of these analyses will inform investigators as to what modes of prevention and therapy might be designed for particular tumour types. The Min strain thereby presents an opportunity to discover protective factors against human colon cancer.

Adenomatous Polyposis Coli↗