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Query: UMLS:C0699790 (colon cancer)
 28,837 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The association between sebaceous neoplasms of the skin and visceral cancers, known as Muir-Torre syndrome, is described in three patients, including one with an extensive history of cancer in his family. The first patient, a 54-year-old man, developed multiple sebaceous adenomas, epitheliomas, and carcinomas in association with a colonic carcinoma 6 years after cardiac transplantation. Family history in this patient disclosed colon cancer in 17 relatives. The second patient was a 51-year-old man who had recurrent adenocarcinoma of the sigmoid colon, adenocarcinoma arising in Barrett's esophagus, and sebaceous epithelioma during a period of 15 years. The third patient was a 90-year-old man with a sebaceous adenoma followed 5 months later by adenocarcinoma of the sigmoid colon with liver metastases. Muir-Torre syndrome in 129 other patients published in the literature is reviewed. Although it is a rare disease, Muir-Torre syndrome requires recognition because skin lesions may be the first sign of the syndrome and this may lead to early diagnosis of associated visceral cancers. Moreover, because this syndrome appears to be inherited, family members should be screened for visceral cancer, especially colorectal adenocarcinoma.
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PMID:Clinicopathological relevance of the association between gastrointestinal and sebaceous neoplasms: the Muir-Torre syndrome. 770 22

Hyperplastic polyps of the colon reveal a geographic distribution similar to that of colorectal cancer and adenomatous polyps. However, unlike adenomas--known precursors of colorectal cancer--little is known about the etiology or clinical significance of the hyperplastic polyp. In this prospective study, we set out to determine the main dietary and other lifestyle factors in the United States that might be associated with this lesion. Hyperplastic polyps of the distal colon and rectum were diagnosed in 219 of 12,922 men of the Health Professionals Follow-up Study having had an endoscopic procedure between 1986 and 1992, and 175 of 15,339 women of the Nurses' Health Study who had undergone an endoscopy for a variety of reasons between 1980 and 1990. After adjusting for age, family history of colon cancer, history of previous endoscopy, and total energy intake using multiple logistic regression, those consuming 30 g or more of alcohol per day were at increased risk relative to nondrinkers among men (relative risk [RR] = 1.69; 95 percent confidence interval [CI] = 1.01-2.80) and women (RR = 1.79, CI = 1.02-3.15). Current smoking also was found to be associated strongly positively with hyperplastic polyps in men (RR = 2.45, CI = 1.59-3.75) and women (RR = 1.96, CI = 1.16-2.86). High intake of folate was associated inversely with risk in both men (RR = 0.74, CI = 0.49-1.11, between high and low intakes of folate) and women (RR = 0.45, CI = 0.28-0.74, between high and low intakes of folate). Among macronutrients, a suggestive increase in risk existed with intake of animal fat, although this was attenuated in the full multivariate model (RR[men] = 1.48, CI = 0.94-2.41, and RR[women] = 1.22, CI = 0.77-1.94) between high and low quantities of animal fat intake. These prospective data provide evidence of associations between low folate intake, alcohol consumption, and current cigarette smoking, and risk of hyperplastic polyps of the distal colon and rectum. These same factors also have been found to be related to adenoma and cancer of the colon. The hyperplastic polyp is an indicator of populations at high risk for colorectal carcinoma, and it also may serve as a marker for factors that influence neoplastic evolution.
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PMID:Diet, alcohol, and smoking and the occurrence of hyperplastic polyps of the colon and rectum (United States). 771 35

Epidemiological studies have suggested that increased intake of calcium (Ca) or aspirin (ASA) is associated with a reduced risk for colon cancer. To delineate a possible mechanism of action, the present study used male F344 rats in an azoxymethane (AOM)-induced colon tumor model to study the single and interactive effects of Ca and ASA on cholic acid-promoted experimental colon carcinogenesis. Following initiation with AOM, a promotion diet containing 0.5% cholic acid was fed for 34 weeks until the adenoma development stage. Cholic acid was used as a surrogate for high-fat diets and to promote carcinogenesis. Diets were supplemented with CaCO3 (2% Ca by weight), 250 p.p.m. ASA, or both. After 34 weeks, the diets were switched during the progression stage and rats were killed at week 51. Several intermediate endpoints were examined during the course of AOM carcinogenesis to determine their reliability as predictors of colon cancer risk. Intermediate endpoints included colon crypt height measurement, colon mucosal ornithine decarboxylase (ODC) and colon mucosal protein kinase C (PKC) activities. The biomarkers were examined at the beginning of the study at 2 weeks, and thereafter at 5, 15, 30 and 40 weeks of dietary treatment. Animals were necropsied at week 51 and tumor incidence and numbers were analyzed for correlation with biomarkers. Survival was highest in the group fed CaCO3 during the promotion stage and tumor burden was lowest in groups fed CaCO3 during this stage. Supplementation during the progression stage was ineffective. The cholic acid promotion model resulted in increased ODC which was inhibited by intervention during the promotion stage with Ca, but not ASA. PKC was also activated by cholic acid feeding, and this effect was modulated by intervention in the promotional stage with Ca or ASA. Colon tumor incidence and burden was increased by cholic acid promotion and decreased by Ca, but not affected by ASA. In summary, Ca is a more effective chemopreventive agent in cholic acid-promoted colon carcinogenesis than ASA, impacting both incidence and tumor number. Colonic ODC, but not PKC may be a suitable predictor of risk and response in chemoprevention trials for colon cancer.
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PMID:Chemopreventive effects of calcium but not aspirin supplementation in cholic acid-promoted colon carcinogenesis: correlation with intermediate endpoints. 772 52

Polymorphic N-acetyltransferase (NAT2), an enzyme present in the colon, may effect incidence of colon cancer. Individuals with NAT2 fast acetylator genotypes may have higher colon cancer risks due to faster conversion of certain carcinogens to mutagens. We determined NAT2 genotypes in 447 subjects with distal colon adenomas and in 487 controls. No significant increase in adenoma prevalence among fast acetylators was observed. However, there was a suggestion of ethnic differences in NAT2 effects. For example, white fast acetylators potentially had slightly increased risks for adenomas (odds ratio, 1.29; 95% confidence interval, 0.90-1.84), whereas fast acetylation was potentially protective among blacks (odds ratio, 0.64; 95% confidence interval, 0.32-1.28). The apparent difference between blacks and whites may simply reflect random variation around an overall null effect, or it could represent a real difference. There was preliminary evidence for a possible interaction between NAT2 and the glutathione transferase M1 null genotype. Smokers' adenoma prevalence was 10-fold higher for fast acetylators with the null genotype compared to slow acetylators without the null genotype. Large, multiethnic populations and analysis of combinations of genes for carcinogen metabolism may be needed to further assess the role of NAT2 in colorectal tumorigenesis.
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PMID:Acetylation polymorphism and prevalence of colorectal adenomas. 774 94

A 59-year-old male with history of sigmoid colon cancer had a high serum-CEA level and was referred for the evaluation of metastatic liver disease. Ultrasonography and computerized tomography showed two tumours in the liver. Macroscopically, these were in segment 4 (S4) and 2 (S2). Histologically, the tumour in S4 showed a number of bile ductules with variable amounts of stroma, an appearance compatible with bile duct adenoma (BDA). There were markedly atypical ductules of various sizes, the epithelium of which had coarsely granular/hyperchromatic large nuclei, in some areas of the lesion. These atypical ductules showed invasive growth into the liver parenchyma. Some cystically dilated ductules with bile plugs resembling bile duct hamartoma (BDH) were also seen. The other tumour in S2, was a metastatic adenocarcinoma from sigmoid colon and showed strongly positive staining for CEA. Since the lesion in S4 of our case is solitary and most of histological features are similar to those of BDA with markedly atypical bile ductules, we consider that this may be the first case of cholangiocarcinoma associated with BDA with focal area of BDH. It is possible that the adenoma-carcinoma sequence occurs in biliary tumours.
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PMID:Cholangiocarcinoma arising in bile duct adenoma with focal area of bile duct hamartoma. 775 93

Calcium supplementation decreases the incidence of colon cancer in animal models and may prevent colon cancer in man. Potential mechanisms include binding of mitogens and direct effects of calcium on colonic epithelial cells. In this study, the effects of extracellular calcium on epithelial cell growth and differentiation were studied in three colon carcinoma and two colonic adenoma cell lines. The characteristics studied included morphology, cell cycle kinetics, [Ca2+]IC (intracellular calcium concentration), proliferation, and expression of differentiation markers such as carcinoembryonic antigen (CEA) and alkaline phosphatase (AP). Sodium butyrate (NaB) and 1,25-dihydroxyvitamin D3 were used as controls in the latter three assays as these two agents are known differentiating agents. Alteration of [Ca+2]EC (extracellular calcium concentration) did not affect carcinoembryonic antigen (CEA) or alkaline phosphatase (AP) expression. NaB enhanced the expression of AP three-fold and CEA five-fold. This effect was augmented by increasing [Ca2+]EC. The exposure of cells to 1,25-(OH)2-Vitamin D3 increased CEA but not AP. [Ca2+]IC increased in response to 1,25-(OH)2-vitamin D3 and NaB but not with variation in [Ca2+]EC. Increased [Ca2+]EC inhibited proliferation of well-differentiated cells, but had no effect on poorly-differentiated cells. Morphological studies showed that extracellular calcium was necessary for normal cell-cell interactions. These studies have demonstrated direct effects of calcium on colonic epithelial cells which may contribute to the protective effects of dietary calcium against colon cancer. Loss of responsiveness to the antiproliferative effects of [Ca2+]EC with de-differentiation suggests that calcium supplementation may be most beneficial prior to the development of neoplastic changes in colonic epithelium.
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PMID:The effect of extracellular calcium on colonocytes: evidence for differential responsiveness based upon degree of cell differentiation. 777 41

Gastrointestinal bleeding is believed to cause iron-deficiency anemia (IDA). The information concerning ideal evaluation of the gastrointestinal tract and exact findings in patients with IDA is scant. The aim of this study was to prospectively evaluate patients with IDA for gastrointestinal lesions potentially causing IDA at a US Army Teaching Medical Center with Gastroenterology Fellowship. Seventy patients with IDA had esophagogastroduodenoscopy (EGD) and colonoscopy, and if this evaluation was unremarkable, then small bowel biopsy was obtained at EGD to evaluate for celiac disease. Enteroclysis was done if endoscopic evaluation was negative. At endoscopy, at least one lesion potentially accounted for the IDA in 50 (71%) patients. At colonoscopy, 21 (30%) patients had 22 lesions (four colon cancer, seven adenoma > 1 cm, six vascular malformation, four severely bleeding hemorrhoids, one ileal Crohn's); at EGD, 39 (56%) patients had 43 lesions (11 gastric erosion, 10 esophagitis, four vascular malformation, four celiac disease, three gastric cancer, three gastric ulcer, three duodenal ulcer, two gastric polyp > 1 cm, one duodenal lymphoma, one esophageal cancer, and one duodenal Crohn's). Twelve (17%) patients had both upper and lower gastrointestinal tract lesions. Twenty-four of 32 (75%) patients with positive fecal occult blood test had potentially bleeding lesions compared to 24 of 38 (63%) patients with negative fecal occult blood test (P > 0.05). Six of nine patients with malignancy had positive fecal occult blood test. Twenty patients with normal endoscopy and small bowel biopsy had normal enteroclysis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Prospective evaluation of gastrointestinal tract in patients with iron-deficiency anemia. 778 48

Most studies on colorectal carcinogenesis suggest a field defect, preceding overt development of cancer. The low incidence of adenomatous polyps in the African population, however, suggests that there may be an alternative route for cancer development. The aim of the study was to discover if the difference in incidence of colorectal cancer in Africans compared with the white population is reflected in a different pattern of cell proliferation. Histological normal mucosa from 30 patients (15 white South African (W), 15 South African Africans (A)) with confirmed colon cancer were examined. Proliferating cells were detected using the Ki-67 antigen. In addition, cell proliferation data were obtained, from 30 age matched controls (15 Africans, 15 white South Africans), without colorectal disease. The African controls were significantly younger (mean (SD) (A: 42 (20), W: 66 (13), p < 0.05)) than the white controls. The second control group had a significantly higher mean (SD) total labelling index (W: 11 (3), A: 6 (4), p < 0.05). In addition the proliferative pattern of the white group without evidence of colorectal cancer showed a comparatively large amount of dividing cells in compartment 2, compared with African controls (mean (SD) (W: 21 (8), A: 9 (8), p < 0.05)). Mucosa from Africans with cancer showed a proliferative pattern with the same increased total labelling index (A: 15 (5), W: 16 (6), p = NS, phase II proliferative lesion) and an even more pronounced upward expansion (phase I proliferative lesion) compared with white cancer patients. This suggests that the mechanism of colorectal carcinogenesis is similar in Africans and the white population. The lack of clinical evidence of the adenoma-carcinoma sequence, and the incidence of cancer at a comparatively young age in Africans may be explained by the fact that colorectal cancer in this ethnic group behaves more aggressively and that adenomatous polyps are rapidly converted into overt cancer before detection.
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PMID:Colonic cell proliferation in two different ethnic groups with contrasting incidence of colon cancer: is there a difference in carcinogenesis? 779 18

Clinical and histological characteristics of non polypoid colorectal cancers with an hereditary predisposition are presented. The various known genetic syndromes (hereditary non polyposis colorectal cancers, Lynch syndrome type I and type II, Torre-Muir's syndrome, hereditary flat adenoma syndrome) are discussed to find a possible correlation between this nosological classification and their molecular substratum. The main problem today, is to correctly define the population of hereditary predisposed patients to colon cancer, in order to seek and identify the major responsible gene. Any physician, specialist or not, should be encouraged to give the details of the cancer familial context of his patients, in order to aid the oncologist geneticist in his task.
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PMID:[Criteria of genetic predisposition to hereditary non polyposis colorectal cancers]. 794 88

A 15-year-old female presenting with anemia and positive for occult blood was diagnosed as having an adenomatous polyp with mild atypia in the cecum by colonoscopy. Microscopically, the majority of the surface of the tubulovillous adenoma was occupied by a well-differentiated adenocarcinoma, indicating that the adenoma-carcinoma sequence is involved in the development of colon cancers, even in children. Forty-three cases of proven carcinoma of the colon in Japanese children aged under 15 years are also reviewed. The majority of the patients were aged over 10. Although an emergency laparotomy was undertaken in 42.5% of these patients, the signs and symptoms observed in these children did not markedly differ from those of adults. Colon cancer should not be excluded in children only on the basis of age, and barium enema and colonoscopy should therefore be applied to pediatric patients with unexplainable bleeding and abdominal pain, especially those over 10 years of age.
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PMID:Carcinoma of the colon in children: case report and review of the Japanese literature. 800 May 15


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