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At least 613 records · Page 34Linked to original sources
PubMed1992

Congenital hypertrophy of retinal pigment epithelium in patients with colonic polyps associated with cancer family syndrome.

Congenital hypertrophy of retinal pigment epithelium (CHRPE) has been shown to be a frequent extracolonic manifestation of adenomatous polyposis coli (APC). The presence of CHRPE in patients with adenomatous polyps from families with cancer family syndrome suggests possible involvement of the APC gene locus in syndromes associated with less florid polyp formation than seen in APC. It also emphasises that caution must be exercised in using the presence of CHRPE clinically as a marker for APC in isolated at-risk individuals.

Adenoma↗
PubMed1993

Design and analysis of studies to reduce the incidence of colon polyps.

Decisions regarding the design and analysis of a phase III study to reduce the incidence of colorectal polyps must take into account two complicating factors: the possibility that polyps are missed during screening exams, and variable lengths of follow-up. In this paper we investigate the effects due to misclassification on the power of statistical tests to detect a change in polyp recurrence rates. We also use Monte Carlo studies to examine the relative efficiency of different methods of adjusting for variable times of follow-up.

Bias↗
PubMed1999

Colon polyp registries and colorectal cancer control.

This cohort of 252 subjects in the Roger Williams Hospital Polyp Registry who had adenomatous polyps removed in 1990, was followed for 6 years. Thirty subjects died during that period. Follow-up rate for the 222 living patients (88.1% of total) was 85%. New adenomatous polyps were found in 59% of the endoscoped subjects. Risk factors for new polyps included family history of colorectal carcinoma (p = 0.00079), right-sided location (p = 0.0108), and (probably) prior adenomatous polyps (p = 0.0595). In addition, three colorectal carcinomas, two of which were Dukes stage A, were found 1, 1, and 6 years after index polypectomy. If, as is common practice, the two first-year cancers are excluded, the observed incidence of metachronous colorectal cancer was 0.8/1000 patient years, which is substantially less than the expected incidence of such carcinomas in reference populations. Compared to the 1984 and 1987 cohorts in the polyp registry, colonoscopy was used more frequently and sigmoidoscopy less so for surveillance. Within the sigmoidoscopy group, the flexible instrument continued to rise in popularity as compared with rigid sigmoidoscopy. In addition to helping reduce the incidence of metachronous colorectal carcinomas, the polyp registry also serves the educational function of sensitizing physicians and their patients to the need to detect and treat these premalignant lesions. Enrollees in the registry also provide a source for studies designed to evaluate possible inhibitory effects of dietary, chemopreventive, and other agents on colorectal neoplasias.

Adenomatous Polyposis Coli↗
PubMed1994

Aberrant expression of nitric oxide synthase in human polyps, neoplastic colonic mucosa and surrounding peritumoral normal mucosa.

The expression of nitric oxide synthase (NOS) was studied by NAD(P)H diaphorase histochemical localization method in (i) individual cells of the normal colonic mucosa (n = 13) which served as control, (ii) colonic polyps (n = 14), (iii) colonic carcinoma (n = 20) and (iv) peritumoral mucosa (2 and 5 or 10 cm away from the tumor). Four of the tumor specimens had normal epithelium adjacent to the cancer, which thus served as an internal control. The expression of NOS activity in colon cancer was significantly reduced as compared to the control group of individuals (P < 0.004); undetectable in 25%, diminished in 45%, normal in 30%. On comparing the expression in normal mucosa and polyps there was a significant reduction of the expression in polyps (P < 0.027); undetectable in 14%, reduced in 35%, normal in 51%. When compared to the peritumoral mucosa at 2 and 10 cm the tumor showed a significant reduction in expression of NOS activity (P < 0.001 and P < 0.0001 respectively). There was no significant difference seen in the expression at 2 and 10 cm (P = 0.329). The peritumoral mucosa at a distance of 2 cm away from the tumor when compared to the control mucosa showed no significant difference (P = 1.000), although there is a tendency to a high normal expression of NOS activity in the mucosa at a distance of 2 cm. Similarly, there was no significant difference between the control mucosa and the peritumoral mucosa obtained at a distance of 10 cm (P = 0.383). The expression of NOS activity in all tissues examined was abolished by preincubation of tissue with the selective NOS inhibitor L-NMMA but not with D-NMMA. Our data showed extensive and significant reduction as identified by the NAD(P)H diaphorase method in the expression of NOS activity, thereby reflecting the activity of nitric oxide in colon cancer and colonic polyps. The generalized suppression of this activity, which precedes the onset of overt neoplasia, may be an important event in colon carcinogenesis. This aberrant expression could also be compatible with the selective advantage to either tumor promotion and metastatic progression or to tumoricidal activity.

Adenocarcinoma↗
PubMedDate not supplied

[Adenomatous polyps in colon and rectum after cholecystectomy].

The frequency of rectal and colonic polyps was compared in 33 patients with history of cholecystectomy and 37 patients without it. The data were evaluated retrospectively from our medical bank records. We found a major incidence of adenomatous polyps in the group of patients with cholecystectomy, the same in females as in males, with a female prevalence in 2.7:1 ratio in contrast with the group without surgery, where the ratio was 1.5:1 with a male prevalence. We didn't find any association between cholecystectomy and colorectal cancer. All the patients with adenocarcinoma were in the group without cholecystectomy.

Adenocarcinoma↗
PubMed1975

Perifollicular fibromatosis cutis with polyps of the colon--a cutaneo-intestinal syndrome sui generis.

In the present study, a peculiar fibromatosis cutis in two siblings has been reported the dermatosis being characterized by innumerable perifollicular fibromas on face, neck and trunk as well as multiple fibromata pendulantia. Since the father allegedly had skin lesions resembling those of his two affected children, an inherited condition is assumed for the disease manifesting itself rather late in age. In the female patient, several adenomatous colon polyps one being transformed into carcinoma were found. Since the association of distinct epithelial and mesenchymal tumours of the skin and the cranial bones with multiple colon polyps is typical for Gardner's syndrome, we have discussed in detail the possiblity of an unknown variant of it. On the other hand, most features of Gardner's syndrome (cutaneous and subcutaneous epidermoid cysts, desmoid tumours, generalized osteomas, a marked multitude of colon polyps, early manifestation of skin and bone changes) were absent in both cases whereas, to our knowledge, in Gardner's syndrome perifollicular fibromas have never been seen. Since perifollicular fibromas are organoid tumours of the mesenchymal hair sheath being clearly defined both clinically and histologically, they must not be confused with the equally well characterized cutaneous tumours of Gardner's syndrome. We are prone to assume that the (irregular?) ASSOCAITION OF MULTIPLE PERIFOLLICULAR FIBROMAS AND COLON POLYPS Represents a distinct nosological entity neither identical with Gardner's syndrome nor with any other known dermo-intestinal syndrome. Thus, perifollicular fibromatosis should alert the dermatologist to consider periodic thorough examination for intestinal polyps the more as they may change into malignant growth.

Adult↗
PubMed2005

Analysis of PTEN gene mutations in Korean patients with Cowden syndrome and polyposis syndrome.

PURPOSE: PTEN (phosphatase and tensin homologue deleted in chromosome 10) is a candidate tumor suppressor gene. Mutations of this gene are responsible for PTEN hamartoma tumor syndromes, including Cowden syndrome, Bannayan-Riley-Ruvalcaba syndrome, Proteus syndrome, and Proteus -like syndromes. Recently, PTEN mutations were identified in several human neoplasms. We analyzed the DNA of various organs and lesions in Korean patients with Cowden syndrome, their family members, and patients with familial adenomatous polyposis for germline or somatic PTEN mutations. METHODS: The 11 patients included in this study were 5 patients with Cowden syndrome, 4 of their family members, and 2 patients with familial adenomatous polyposis. Deletions and mutations in exons 1 to 9 of the PTEN gene were evaluated by polymerase chain reaction-single strand conformation polymorphism and sequencing analysis in esophageal acanthosis, gastric polyps, colonic polyps, skin lesions, and peripheral blood mononuclear cells. To exclude common polymorphisms, 240 controls were tested. RESULTS: All patients with Cowden syndrome showed several to numerous polyps in the gastrointestinal tract. A missense mutation at codon 217 (GTC to GAC, Val to Asp) in exon 7 was identified in one Cowden syndrome patient, and a nonsense mutation at codon 211 (TGC to TGA, Cys to stop) in exon 6 was identified in a second patient. Identical mutations were found in all tissue samples, including colonic polyps, from each patient. No PTEN mutations were found in their family members or in any patient with familial adenomatous polyposis. None of tested controls contained a mutation. CONCLUSIONS: We have identified two new germline PTEN mutations in Korean patients with Cowden syndrome. Mutations in the introns and regulatory regions of the PTEN gene may be present in additional patients with Cowden syndrome and polyposis syndrome.

Adenomatous Polyposis Coli↗