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PubMed1993

[Diagnosis of colonic tumors and chronic inflammatory colonic diseases by hydrocolonic sonography].

Retrograde instillation of water into the colon makes it possible to visualize the colon sonographically from the rectosigmoid transition to the cecum in 97% of the patients examined. The sonographic views obtained using this technique, which is called hydrocolonic sonography, show the echo-free intestinal lumen, the five individual layers of the colon wall and the connective tissue surrounding the colon. Colonic polyps and carcinomas appear sonographically as echogenic structures projecting from the intestinal wall into the lumen. Colonic polyps larger than 7 mm diameter can be identified in 91% of cases, and the sensitivity of the technique in the detection of carcinomas of the colon is 97%. In addition, detailed evaluation of the structure of the bowel wall permits more precise staging of tumors of the colon. Aside from such localized changes, hydrocolonic sonography can also demonstrate typical changes in the wall structure in chronic inflammatory large-bowel diseases. In acute Crohn's disease the normal stratified appearance of the colonic wall is no longer in evidence and the wall appears visible thickened. In contrast, in patients with acute ulcerative colitis the normal sonographic stratified appearance of the colonic wall is maintained. Hydrocolonic sonography enables a detailed sonographic examination of the colonic lumen and the colon wall, thus providing additional information and allowing more precise diagnosis of many diseases of the colon.

Colonic Neoplasms↗
PubMed1991

Gardner syndrome: study and follow-up of a family.

A study is in progress of a family (Family P) with Gardner syndrome (familial adenomatous polyposis with extraintestinal manifestations-FAPG). Occult bone lesions of the jaws and ocular fundus lesions were found in a number of affected and at-risk relatives. In some, these "markers" were found early in life before the appearance of colonic polyps. Family P is remarkable for differences in expression of the gene manifested by differences in the age-at-onset of polyps of the colon, in number and size of polyps, and in occurrence of desmoids. These differences may explain why some at-risk relatives wisely followed medical surveillance plans while others, who lacked symptoms, failed to do so. Others without medical guidance undertook their own independent "treatment." As knowledge about extracolonic lesions has increased and surgical treatment for FAPG improved from the time the first affected member of Family P received her diagnosis in 1953, the outlook for survival has also improved. Family communication and that among professionals treating families with FAPG may be improved as worldwide Polyposis Registries increase in number. The risk of postsurgical extraintestinal complications is reason enough to urge life-long medical surveillance for all at-risk relatives.

Adenomatous Polyposis Coli↗
PubMed1989

Regional differences in concentrations of regulatory peptides in human colon mucosal biopsy.

The study was undertaken to examine regional differences in the concentrations of five regulatory peptides in the human colonic mucosa. Biopsies were obtained during routine colonoscopy from 33 patients whose colonic mucosa was macroscopically and histologically normal. Regulatory peptides were extracted, and measured by specific radioimmunoassays. Concentrations of three peptides that are present predominantly in endocrine cells within colonic mucosa increased significantly towards the rectum: Mean concentrations of peptide YY, enteroglucagon, and somatostatin were about three times greater in the rectum than in the cecum. However, concentrations of two peptides that are present in mucosal nerve fibers diminished significantly towards the rectum: Mean rectal concentrations of vasoactive intestinal peptide and peptide histidine methionine were both about 0.6 of mean cecal concentrations. Concentrations of all five peptides were lower in biopsies taken from colonic polyps than in normal colonic mucosa. Regional differences in colonic mucosal concentrations of regulatory peptides probably reflect differences in the physiological functions of different parts of the colon.

Adolescent↗
PubMed1994

Increased prevalence of colonic adenomas in patients with acromegaly.

Forty-nine acromegalics and 57 controls matched for age and sex underwent colonoscopy. The control group consisted of patients investigated because of atypical abdominal complaints compatible with irritable bowel syndrome or constipation. The exclusion criteria for both groups included: age over 75 years, previous colonic polyps or cancer, previous colonic surgery, rectal blood loss, anemia, previous abdominal radiation, sigmoidoscopy, colonoscopy or barium enema performed for any indication within 3 years prior to the present study. Colonoscopy was successful in reaching the cecum in 72 and 77% of the controls and acromegalics, respectively (p = NS). Eleven (22%) of 49 acromegalics had biopsy-proven colonic adenomas versus only five (9%) of the control group (p < or = 0.05). Multiple adenomas were found in three of the 11 acromegalics and in none of the controls. In five of these 11 patients and in only one of the controls, at least one adenoma was located in the right colon. In addition, acromegalics tended to have larger adenomas. The group of acromegalics with and without adenomas did not differ significantly in age or duration of active disease. In conclusion, the present study shows that acromegalic patients have an increased risk of developing colonic adenomas.

Acromegaly↗
PubMed1989

[Fiber-optic endoscopy of the lower gastrointestinal tract in children].

Between 1978 and 1985 565 lower gastrointestinal endoscopies were performed in children. In 221 cases the cause of rectal bleeding was explored, in 227 the suspicion of colitis and in 25 of polyposis was verified. To evaluate the results of treatment (polypectomy, surgical procedures and medical therapy in inflammatory bowel disease) 121 examinations were done. With increasing experience the complete colonoscopy was performed more often. In 1985 coecum and ileum terminale was reached in almost all children in whom it was needed (75% of all examinations). The inflammatory changes were revealed on 230 occasions. In 78 cases colon polyps and in 27 vascular changes were found. The most common cause rectal bleeding were colon polyps (66 cases) and inflammatory changes (554 cases). Less common were vascular changes (10 cases). 32% false negative and 16% false positive results of colonoscopy in diagnosis colitis were obtained when the results of visual findings were compared with histopathological findings. Colonoscopy performed by an experienced colonoscopist rather avoiding general anesthesia is a safe and useful procedure in diagnosing lower gastrointestinal tract diseases in children. The evaluation of colitis should be based on visual findings with biopsy confirmation.

Adolescent↗
PubMed1996

Vitamin C status and colonic neoplasia.

PURPOSE: A subnormal status of vitamin C has been associated with an increased risk for several malignant diseases and may play a causative role in their development. The aim of the present study was to investigate whether this occurs also in neoplasms of the colon. METHODS: We have studied dietary intake and status of vitamin C in a consecutive group of patients with adenomatous colonic polyps (n = 31) and compared it with that of patients with no such history and a normal colonic mucosa, as confirmed by colonoscopy (n = 54). RESULTS: Dietary intake of this vitamin, as assessed by the dietary recall method, was similar in the two groups, as were the levels of vitamin C in plasma and leukocytes. There were no significant differences in intake of dietary fiber, fat, vitamin A, or calcium between the two groups. Lack of association between vitamin C intake or status and colonic polyps persisted after adjustment for potential confounders. CONCLUSION: We conclude that in this population, a deficient status of vitamin C is not an important factor in colonic neoplasia.

Adenomatous Polyps↗
PubMed1988

Colonoscopic polypectomy.

Since the advent of fiberoptic endoscopy and the introduction of colonoscopic polypectomy, a simple and cost-effective procedure has been available to deal with an exceedingly common problem, the colonic polyp. Although polyps in the gastrointestinal tract have a varied natural history, there is strong evidence that adenomatous colonic polyps have a potential for malignant degeneration and that virtually all colorectal cancers arise from adenomatous polyps. This article will review some basic features of the endoscopic approaches and problems associated with polypectomy.

Colonic Polyps↗
PubMed1983

Peanut lectin-binding sites in polyps of the colon and rectum. Adenomas, hyperplastic polyps, and adenomas with in situ carcinoma.

Peanut lectin (PNA) has a specificity for the disaccharide beta-D-Gal-(1 leads to 3)-D-GalNac which is the purported antigenic determinant for the T blood group antigen (TAg). This TAg is considered the immediate precursor of the MN blood group substance. In normal colonic epithelium, PNA binds to the supranuclear (stalk) portion of epithelial cells. This corresponds to the detection of beta-DGal-(1 leads to 3)-D-GalNac in nascent oligosaccharide chains in the Golgi cisternae prior to addition of terminal sialic acid. Colonic carcinomas bind PNA in the "region" of the glycocalyx or in the apical portion of the cell, which represents incomplete glycoprotein synthesis. Eighty-two percent of tubular adenomas, 80% of villous adenomas, and 91% of adenomas with in situ cancer expressed PNA in a supranuclear distribution, reminiscent of normal colonic epithelium. This stalk distribution was seen in goblet cells. Twenty-five percent of tubular adenomas, 43% of villous adenomas and 60% of adenomas with in situ cancer (adenoma portion) expressed PNA in an apical cytoplasmic and/or glycocalyx pattern among nonmucinous columnar cells. In 80% of the cases, the in situ cancer itself expressed PNA in an apical cytoplasmic and/or glycocalyx pattern. Fetal and most colon cancer cells fail to produce mucin goblets and make incomplete glycoproteins. The cytologic localization of TAg by PNA corresponds to the cells' ability to produce mucin goblets. Most adenomas consist of goblet cells, localize TAg to the stalk, and probably make complete MN glycoprotein as does normal colonic epithelium. However, in adenomas, nonmucinous columnar cells localize TAg to the apical cytoplasm and/or glycocalyx region and represent incomplete blood group glycoprotein synthesis.

Adenoma↗
PubMed2004

Peroxisome proliferator-activated receptor-delta attenuates colon carcinogenesis.

Peroxisome proliferator-activated receptor-delta (PPAR-delta; also known as PPAR-beta) is expressed at high levels in colon tumors, but its contribution to colon cancer is unclear. We examined the role of PPAR-delta in colon carcinogenesis using PPAR-delta-deficient (Ppard(-/-)) mice. In both the Min mutant and chemically induced mouse models, colon polyp formation was significantly greater in mice nullizygous for PPAR-delta. In contrast to previous reports suggesting that activation of PPAR-delta potentiates colon polyp formation, here we show that PPAR-delta attenuates colon carcinogenesis.

Animals↗
PubMed1988

In vitro models of human colonic adenomatous polyps.

In this report we describe methods which were used to cultivate cell lines from adenomatous polyps. Many of the techniques used have evolved from our past experience with the cultivation of colonic epithelial neoplastic cells (McBain et al., 1984) and the experience of others successful in the cultivation of benign and cancerous colon tissues. We feel that the preservation of cell-to-cell associations is a key to our successful cultivation of adenomas. Moyer (Moyer and Aust, 1984) has also pointed out the importance of preserving cell-to-cell associations in her successful studies to culture normal and neoplastic colonic tissues. Friedman's primary culture system for adenomatous polyps (Friedman et al., 1981) is further evidence supporting this point. Using the techniques described in this report, three cell lines, two small tubular polyps and one villous polyp, have been established and characterized. These cells can be expanded to numbers that will be sufficient for molecular and biochemical studies, and the cell number will be sufficient to conduct transfection experiments. Paraskeva (Paraskeva et al., 1984) has described two other cell lines derived from adenomatous polyps arising in patients with familial polyposis. The availability of cell lines from tubular and villous polyps make it possible to propose experiments to probe the biology of colonic adenomas.

Adenoma↗
PubMedDate not supplied

Measurement of prostaglandin E2 in rectal mucosa in human subjects: a method study.

It has been demonstrated and confirmed that certain nonsteroidal anti-inflammatory drugs which inhibit cyclooxygenase and the synthesis of prostaglandins and other eicosanoids, can reduce the formation of both colon polyps and cancers in experimental animals given known carcinogens. Additionally, the results of several epidemiologic studies have suggested that nonsteroidal anti-inflammatory drugs may reduce the risk of colon polyp occurrence and/or colon cancer mortality. We have carried out a study to evaluate the methodology of the measurement of prostaglandin E2 (PGE2) in human colonic mucosa because its concentration may serve as a valuable intermediate marker of the pharmacological activity in Phase II studies of nonsteroidal anti-inflammatory drugs as colon cancer preventive agents. We studied all aspects of the actual measurement of PGE2 including the extraction efficiency of the PGE2 from the mucosa, the precision of the assay and calculation of the PGE2 content in terms of milligrams of protein in the sample, the inhibition of PGE2 by indomethacin over time, the reproducibility of the measurement within one homogenate, the rate of PGE2 production over time, the effect of adding indomethacin versus snap freezing on PGE2 production, the stability of PGE2 in tissues over time stored in liquid nitrogen, and the variability of the measurement of PGE2 in separate biopsies from one individual. Our studies indicated that the most reliable method for accurate and consistent measurements of PGE2 was to add the mucosal tissue instantly after biopsy to an indomethacin buffer that effectively inhibited the in vitro formation of PGE2.

Biopsy↗
PubMed2002

[Nonsteroidal anti-inflammatory drugs and the risk of polyposis, colon carcinoma and rectal carcinoma].

OBJECTIVE: To probe the risk of colorectal polyp, colon and rectal carcinoma and the intake of NSAIDs. METHODS: Case-control study participants were from patients who underwent colonoscopy at different hospitals, the persons with the above disease was as cases, and those without the above diseases was as controls. Use of NSAIDs was assessed by interviewing the participants with a questionnaire which include a list of NSAIDs and related dietary and life style factors and family history. RESULTS: There are 37 cases of colorectal polyp, 105 cases of colon carcinoma and 142 cases of rectal carcinoma and 66 controls. Adjusted for potential confounders, the risk of colorectal polyposis, colon carcinoma and rectal carcinoma were markedly reduced by NSAIDs. The OR values were 0.21 (95% CI 0.07-0.65, P = 0.007), 0.13 (95% CI 0.05-0.35, P < 0.001), 0.15 (95% CI 0.11-0.58, P < 0.001) respectively. The risk of the above diseases were also reduced markedly by aspirin, the OR values were 0.265 (95% CI 0.07-0.96, P = 0.044), 0.10 (95% CI 0.03-0.35, P < 0.001), 0.15 (95% CI 0.04-0.49, P = 0.002) respectively. The risk of colon carcinoma was also reduced by profen, with the OR being 0.11 (95% CI 0.02-0.64, P = 0.014). CONCLUSIONS: Aspirin and other NSAIDs could reduced the risk of colorectal polyp, colon carcinoma and rectal carcinoma markedly. Aspirin was the most prospective chemopreventive agents for colorectal polyp, colon and rectal carcinoma for its capability of reducing the risk of cardio-cerebral vascular disease as well.

Adult↗
PubMed1981

Colonoscopic polypectomy.

Seven hundred and forty-one colonic polyps have been removed by colonoscopic polypectomy during 300 examinations. Up to 36 polyps were removed at a single examination. Colonoscopic treatment of villous adenomas to 7 cm has been successfully performed in elderly and infirm patients. There were no deaths or incidents of perforation and the only significant complications were two secondary haemorrhages requiring transfusion. The presence of a polyp was not definitely reported in 40% of barium enema X-ray examinations carried out within three months of polypectomy. Double contrast X-ray examinations were significantly more sensitive in the detection of polyps. Colonoscopic polypectomy is a safe and effective technique. All colonic polyps should be removed by this technique after diagnosis.

Adenoma↗