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PubMed1980

Immunohistologic study of blood group substances in polyps of the distal colon. Expression of a fetal antigen.

Forty-four polyps and 14 adenocarcinomas of the left colon from 28 patients were studied for the presence of blood group substances of the A, B system, using the method of specific erythrocytic adherence. Forty-one percent of all polyps and 57% of all cancers were found to have reactivity for blood group substances. Fifty-four percent of villous adenomas (seven of 13), 39% of tubular adenomas (five of 13), 14% of mixed tubulovillous adenomas (one of seven), and no hyperplastic polyps (zero of four) showed reactivity for blood group substances. Lesional blood group substance reactivity, when present, was the same as that for the patient's own blood group type, with the exception of two patients of B blood group type, whose lesions had A-blood group substance reactivity. Cytologic atypia showed no correlation with the presence of blood group substances. Polyps with blood group substance reactivity were seen more frequently in patients with cancer. Twelve patients had both a cancer and a polyp studied, with both polyp and cancer showing similar blood group substance reactivity for nine of these patients. A, B, H-blood group substances in the left colon are normally absent in the adult and present only in the fetus. The reappearance of these fetal antigens in both polyps and cancers adds immunologic evidence to the theory that colonic adenocarcinoma evolves through a polyp-cancer sequence.

ABO Blood-Group System↗
PubMedDate not supplied

Adenomas and carcinomas may be histologically detected in apparently normal colonic mucosa. A study of carcinogen-treated rats.

Clinical reports indicate that colonic neoplasias may be overlooked at colonoscopy. We investigated, in an experimental model, whether both gross and high power microscopical examinations could detect all induced colonic neoplasias. Forty-nine Sprague-Dawley rats received 1,2-dimethylhydrazine for 27 weeks. The colons were scrutinized grossly and at high-power microscopy complemented with chromoscopy. Biopsies were obtained from all mucosal alterations seen at gross and at high power microscopy. The gross examination of the colonic specimens in the 49 animals revealed 196 polyps or suspected polyps. Histology showed that 85.2% (167 out of 196) were adenomas or adenocarcinomas. The remnant polyp-free colons were subsequently examined by high-power stereo microscopy (46 magnifications). Fifty-five new lesions were detected and removed. Histology showed 48.9% (n = 24) additional neoplastic lesions in the 49 colon specimens. The remnant polyp-free colons were subsequently processed for histology. The sections showed 57 additional neoplastic lesions in the 49 colon specimens: 93.0% (n = 53) were adenomas (n = 35) and crypt dysplasias (n = 18), while the remaining 7.0% (n = 4) were invasive carcinomas. Experimentally-induced colonic neoplasias may be overlooked even after a careful scrutiny of the colonic mucosa using high-power optical devices.

1,2-Dimethylhydrazine↗
PubMedDate not supplied

Differential activation of total and EGF receptor (EGF-R) tyrosine kinase (tyr-k) in the rectal mucosa in patients with adenomatous polyps, ulcerative colitis and colon cancer.

BACKGROUND/AIMS: Tyrosine kinase and a number of growth factors, especially EGF and TGF-alpha are known to stimulate proliferation in much of the gastrointestinal tract, including colon. In humans increased colonic mucosal proliferative activity has been observed in numerous premalignant lesions including adenomatous polyps and ulcerative colitis. The aim of the present study was to determine the differences of proliferative patterns in patients with adenomatous polyps, ulcerative colitis and colonic adenocarcinoma as reflected by rectal mucosa tyrosine kinase, EGF receptor tyrosine kinase and PCNA and to evaluate the role of tyr-k in colonic mucosal cell proliferation during carcinogenic process. MATERIALS AND METHODS: The study population comprised 40 patients, aged 17-74 years (mean 57), in which 10 patients had adenomatous polyps, 10-ulcerative colitis in remission phase, 10- colon adenocarcinoma and 10 healthy controls. After informed consent 6-8 rectal mucosal biopsy specimen were obtained at 10 cm from the anal verge at the beginning of the colonoscopy examination and at least 10 cm away from any macroscopic mucosal changes. RESULTS: Mean PCNA labeling indices in patients with colon adenocarcinoma, adenomatous polyps, ulcerative colitis ulcerosa and healthy controls were respectively: 27.6% +/- 5.75; 12.18% +/- 6.76; 10.9% +/- 5.34 and 1.5% +/- 0.97. PCNA labeling index in rectal mucosa of patients with adenomatous polyps, ulcerative colitis and colon cancer was significantly higher (p < 0.01) than in the control group. An upward expansion of the proliferative compartment was also observed in patients with premalignant and malignant colon conditions as regards to the control group. Total tyrosine kinase activity in the rectal mucosa of patients with polyps was elevated by 219%, with ulcerative colitis by 224% and with colorectal carcinoma by 600% as regards to the control group. EGF receptor tyrosine kinase was increased in colonic mucosa by 35.2% in patients with adenomatous polyps, by 40.6% in patients with ulcerative colitis and by 123% in patients with colon cancer. CONCLUSIONS: Increased values of this enzyme in the above mentioned group of patients may suggest that tyrosine phosphorylation represents an early sign of colonic mucosa susceptibility for cancer development. We conclude, that overall an EGF receptor-associated tyrosine kinase plays an important role in the development of hyperproliferative state of the colonic mucosa and colon carcinogenesis.

Adenocarcinoma↗
PubMed1990

Alcoholic beverages and adenomatous polyps of the sigmoid colon: a study of male self-defence officials in Japan.

The drinking habits of 86 men with adenomatous polyps of the sigmoid colon were compared to those of 1184 men with normal colonoscopy among middle-aged male self-defence officials. After adjustment for rank, smoking history and rice consumption, total ethanol intake was positively associated with the risk of adenomatous polyps. The odds ratio (OR) was 2.4 (95% confidence interval (CI) 1.0-5.5) for men consuming at least 60 ml of ethanol per day. Among five alcoholic beverages (shochu, beer, sake, whiskey and wine), both sake and beer showed a dose-response relationship with the risk of adenomatous polyps although the association with beer was less striking. Shochu was the largest source of ethanol intake in the study population, but there was virtually no association between shochu consumption and adenomatous polyps. Men drinking wine had a significantly increased risk, but these men were too few to examine the relation in detail. The findings suggest that the consumption of specific alcoholic beverages rather than ethanol itself is associated with an increased risk of adenomatous polyps of the sigmoid colon.

Adenoma↗
PubMed2005

Colonic chicken-skin mucosa in children with polyps is not a preneoplastic lesion.

Colonic polyps are common both in adults and children; however, the malignant potential varies according to the type of polyp. Most childhood polyps are solitary juvenile polyps, which have negligible malignant potential. Chicken-skin mucosa (CSM) is an endoscopic finding initially described associated with adenomatous polyps and adenocarcinoma, suggesting a preneoplastic lesion. Subsequently, CSM was described in association with juvenile polyps, suggesting that this mucosal finding is not a precursor to dysplasia. To determine whether CSM represents a preneoplastic lesion, we studied endoscopic colonic mucosal biopsies for markers of cell replication (Ki-67) and malignant transformation (p53) in mucosal biopsies of CSM, normal colonic tissue, tubular adenomas, and adenocarcinomas. Samples were subjected to immunostaining for the presence of Ki-67 and p53. The degree of Ki-67-positive staining cells was similar for CSM and normal colonic tissue, whereas there was significantly increased staining for both tubular adenomas and adenocarcinomas. There was no evidence of p53 staining in CSM and normal colonic mucosa, whereas there was varying degrees of staining in tubular adenomas and adenocarcinomas. The association of CSM with benign juvenile polyps and the absence of histologic markers for increased replication and malignant transformation support the notion that this endoscopic finding is not preneoplastic. Rather, CSM arises in proximity to polyps of all histologic types because of local mucosal damage.

Adenocarcinoma↗
PubMed1993

Clinical significance of diminutive polyps of the rectum and sigmoid colon.

A retrospective review of 637 consecutive colonoscopies with polypectomy in 526 patients was performed to determine the association of small polyps of the rectum and sigmoid colon with more proximal colonic neoplasms. All colonic polyps were proximal to the sigmoid colon in 117 procedures. Proximal neoplasms were found in 32 percent of patients with a single polyp in the rectum or sigmoid colon. The incidence increased to 83 percent for those with three or more polyps. The occurrence of proximal colonic neoplasms was not affected by the size or histologic type of the rectosigmoid polyps. These findings would suggest that total colonic evaluation be considered in all patients with a polyp in the rectum or sigmoid colon regardless of the size or histologic type of the polyp.

Adenoma↗
PubMed1989

Elevated gastrin levels in patients with colon cancer or adenomatous polyps.

Gastrin has been shown to stimulate the growth of carcinogenic-induced colon cancer in animals, and some human colon cancers grown in vitro or as xenografts in nude mice. We determined fasting plasma gastrin levels in control subjects and patients with adenomatous polyps or adenocarcinoma of the colon to determine whether abnormal levels occurred in either patient group. Blood samples were obtained from 73 patients undergoing colonoscopy, primarily for evaluation of Hemoccult-positive stools. Fasting plasma gastrin was significantly greater in patients with adenomatous polyps (24.2 +/- 5.7 pM, N = 25) or colon cancer (84.5 +/- 28.5 pM, N = 20) than in controls (9.9 +/- 0.9 pM, N = 28). Elevations were due to gastrin values greater than control mean + 2 SD in nine patients with polyps (19.5-150.2 pM) and eight with cancer (20.7-403.2 pM). None of the patients had identifiable causes (drugs, prior surgery) for elevated gastrin levels. Our results indicate that elevated plasma gastrin occurs in subgroups of patients with adenomatous polyps or adenocarcinoma of the colon. The cause and potential role of elevated gastrin for polyp and tumor growth in these patients is not known.

Adenocarcinoma↗
PubMed1994

[Determination of bile acids in stools of patients with colonic neoplasms and adenomatous polyps].

Since several years ago, the biliar acids have been incriminated in the etiopathogeny of colon cancer and adenomatous polyps, above all the secondary ones, involved by its aggressive action over the colonic epithelium in these mechanisms. The dietetical habits of developed countries have the high responsibility for this situation, their food pattern being a high animal fat diet, high in refined carbohydrates, animal proteins and low in dietetic fiber (diet type "occidental") unlike to developing countries that have a high natural fiber diet, having a much lower incidence in colon cancer and adenomatous polyps. Dietetic fiber has been studied considering it with a protector effect over the aggressive action of biliar acids on the colon mucous. We have studied 60 patients, 20 of them with colon cancer, 20 with adenomatous and 20 case controls without colonic pathology. All of them had total high biliar acids in stools, a dietetical screening was carried out to determine the intake of animal fat and dietetic fibre during a week. There was a significant correlation in cases of cancer, polyps and biliar acids high in stools. There was also a significant correlation between the undue dietetic habits in colon cancer patients and high bilar acids. In those cases of adenomatous polyps, there was not a significant relation to dietetic habits.

Adenomatous Polyps↗
PubMed2003

Risk factors for advanced colonic neoplasia and hyperplastic polyps in asymptomatic individuals.

CONTEXT: Knowledge of risk factors for colorectal neoplasia could inform risk reduction strategies for asymptomatic individuals. Few studies have evaluated risk factors for advanced colorectal neoplasia in asymptomatic individuals, compared risk factors between persons with and without polyps, or included most purported risk factors in a multivariate analysis. OBJECTIVE: To determine risk factors associated with advanced colorectal neoplasia in a cohort of asymptomatic persons with complete colonoscopy. DESIGN, SETTING, AND PARTICIPANTS: Prospective, cross-sectional study of 3121 asymptomatic patients aged 50 to 75 years from 13 Veterans Affairs medical centers conducted between February 1994 and January 1997. All participants had complete colonoscopy to determine the prevalence of advanced neoplasia, defined as an adenoma that was 10 mm or more in diameter, a villous adenoma, an adenoma with high-grade dysplasia, or invasive cancer. Variables examined included history of first-degree relative with colorectal cancer, prior cholecystectomy, serum cholesterol level, physical activity, smoking, alcohol use, and dietary factors. MAIN OUTCOME MEASURES: An age-adjusted analysis was performed for each variable to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) associated with having advanced neoplasia compared with having no polyps. We developed a multivariate logistic regression model to identify the most informative risk factors. A secondary analysis examined risk factors for having hyperplastic polyps compared with having no polyps and compared with having advanced neoplasia. RESULTS: Three hundred twenty-nine participants had advanced neoplasia and 1441 had no polyps. In multivariate analyses, we found positive associations for history of a first-degree relative with colorectal cancer (OR, 1.66; 95% CI, 1.16-2.35), current smoking (OR, 1.85; 95% CI, 1.33-2.58), and current moderate to heavy alcohol use (OR, 1.02; 95% CI, 1.01-1.03). Inverse associations were found for cereal fiber intake (OR, 0.95; 95% CI, 0.91-0.99), vitamin D intake (OR, 0.94; 95% CI, 0.90-0.99), and use of nonsteroidal anti-inflammatory drugs (NSAIDs) (OR, 0.66; 95% CI, 0.48-0.91). In the univariate analysis, the inverse association was found with cereal fiber intake greater than 4.2 g/d, vitamin D intake greater than 645 IU/d, and daily use of NSAIDs. Marginal factors included physical activity, daily multivitamin use, and intake of calcium and fat derived from red meat. No association was found for body mass index, prior cholecystectomy, or serum cholesterol level. Three hundred ninety-one patients had hyperplastic polyps as the worst lesion found at colonoscopy. Risk variables were similar to those for patients with no polyps, except that past and current smoking were associated with an increased risk of hyperplastic polyps. CONCLUSIONS: Our data endorse several important risk factors for advanced colonic neoplasia and provide a rationale for prudent risk reduction strategies. Further study is needed to determine if lifestyle changes can moderate the risk of colorectal cancer.

Aged↗
PubMed2003

Diagnostic potential of near-infrared Raman spectroscopy in the colon: differentiating adenomatous from hyperplastic polyps.

BACKGROUND: Near-infrared Raman spectroscopy is a promising optical technique for GI tissue diagnosis. This study assessed the diagnostic potential of near-infrared Raman spectroscopy in the colon by evaluating its ability to distinguish between adenomatous and hyperplastic polyps. METHODS: Ex vivo and in vivo Raman spectra of colon polyps were collected by using a custom-built, fiber-optic, near-infrared Raman spectroscopic system. Multivariate statistical techniques, including principal component analysis and linear discriminant analysis, were used to develop diagnostic algorithms for classifying colon polyps based on their spectral characteristics. With the number of samples available, spectral classification of polyps was tested by using a leave-one-out, cross-validation method. RESULTS: Fifty-four ex vivo Raman spectra were analyzed (20 hyperplastic, 34 adenomatous). The spectral-based diagnostic algorithms identified adenomatous polyps with 91% sensitivity, 95% specificity, and 93% accuracy. In vivo, adenomas (n = 10) were distinguished from hyperplastic polyps (n = 9) with 100% sensitivity, 89% specificity, and 95% accuracy. CONCLUSIONS: Near-infrared Raman spectroscopy differentiated adenomatous from hyperplastic polyps with high diagnostic accuracy. To our knowledge, this is the first demonstration of the potential of near-infrared Raman spectroscopy for differentiation of colonic polyps during GI endoscopy.

Adenomatous Polyps↗
PubMed1982

Lymphoid polyps (focal lymphoid hyperplasia) of the colon in children.

Lymphoid polyps (focal lymphoid hyperplasia) of the colon are rare in children. These lesions are benign, but must be differentiated from malignant lymphomas. Grasp biopsies of the lesion are inadequate for this purpose and the polyp should be submitted in toto for pathologic examination. No treatment other than local excision is warranted. Two cases are presented and the literature is reviewed.

Adolescent↗
PubMed2000

Primary intestinal T-cell lymphoma resembling lymphomatous polyposis: report of a case.

We report an interesting case of primary intestinal T-cell lymphoma (ITL) resembling lymphomatous polyposis (LP) in a 24-year-old man. The neoplasm macroscopically showed numerous small polyps throughout the colon and microscopically showed diffuse proliferation of small-sized tumor cells with occasionally cleaved or irregularly shaped nuclei. The tumor cells were immunohistochemically positive for CD3, CD8, TIA-1, and CD56, and a polymerase chain reaction study showed a single band, indicating monoclonal rearrangement of the T-cell receptor beta gene. The phenotypic features in the current case are consistent with those of ITL derived from cytotoxic CD56+ CD8+ intraepithelial lymphocytes. This is the second documented case of primary ITL with a morphologic pattern of LP.

Adult↗
PubMed2007

Nonfamilial juvenile polyposis coli manifesting as massive lower gastrointestinal hemorrhage: report of two cases.

Juvenile polyposis syndrome is an uncommon hamartomatous disorder with gastrointestinal (GI) manifestations of varying degree and malignant potential. We report the cases of an 8-year-old girl and a 5-year-old girl who suffered massive lower GI hemorrhage. Neither patient had a family history of polyposis. After the patients were stabilized, radiological evaluation, laparotomy, and intraoperative colonoscopy revealed multiple polyps in the colon. Both patients underwent total colectomy, mucosal proctectomy, and ileoanal anastomosis. The diagnosis of nonfamilial juvenile polyposis was based on the histological findings and the absence of a family history. To our knowledge, this presentation of juvenile polyposis has been reported only twice before. We discuss the clinical features and diagnosis of juvenile polyposis and the treatment options. Although juvenile polyposis is a rare condition in children, it should be considered in the differential diagnosis of life-threatening GI hemorrhage.

Child↗

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