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At least 1,261 records · Page 70Linked to original sources
PubMed1992

Reduction of mucosal crypt cell proliferation in patients with colorectal adenomatous polyps by dietary calcium supplementation.

The crypt cell production rate was measured in 14 patients with adenomatous colorectal polyps, 17 patients with colorectal cancer and 12 control subjects. The median (interquartile range) rate (cells per crypt per hour) was found to be significantly higher (P less than 0.001) in the polyp (2.45 (1.94-3.20)) and cancer (3.01 (2.35-3.68)) groups compared with controls (1.25 (0.70-1.85)). A double-blind cross-over study was performed in patients with adenomatous polyps consisting of 2 months' treatment, 2 weeks' washout, followed by 2 months' treatment with dietary calcium supplementation (1.25 g day-1) versus placebo. A significant reduction in the crypt cell production rate occurred with calcium treatment compared with the placebo (1.25 (0.6-2.25) versus 2.15 (1.58-3.08) cells per crypt per hour, P = 0.035). This study demonstrates a significant reduction in mucosal cell proliferation by dietary calcium supplementation in patients with adenomatous polyps. Such treatment may be worthy of further investigation in patients at high risk of developing colorectal polyps.

Aged↗
PubMed1988

Urokinase-type plasminogen activator in colorectal carcinomas and adenomatous polyps: quantitative expression of active and proenzyme.

Total urokinase-type plasminogen activator (u-PA) content (proenzyme plus active enzyme) was significantly higher in 20 colorectal carcinomas and in 27 adenomatous polyps than in metaplastic polyps and autologous normal mucosa. u-PA content was also markedly increased in adenomatous polyps and autologous colonic mucosa removed from familial polyposis coli patients. Using a new monoclonal antibody technique to distinguish the proenzyme of u-PA from the active enzyme, we found that 70% of the u-PA in polyp and cancer tissue was present in the proenzyme form compared to 47% in normal colonic mucosa. For colon cancers, there was a significant correlation between their stage of invasiveness and the levels of proenzyme. No correlation was observed between the u-PA content of adenomatous polyps and their size or degree of dysplasia. Study of the u-PA content of the colonic mucosa may offer a useful biochemical correlate of epithelial cell transformation in the colon.

Adenoma↗
PubMed2006

Strengths and weaknesses of dark-lumen MR colonography: clinical relevance of polyps smaller than 5 mm in diameter at the moment of their detection.

PURPOSE: To assess the clinical relevance of dark-lumen MR colonography (MRC) for the detection of colorectal lesions using conventional colonoscopy (CC) and histopathologic examinations as reference standard. MATERIALS AND METHODS: A total of 72 patients underwent MRC and CC. MRC was performed using a contrast-enhanced high spatial resolution T1 weighted 3D volumetric interpolated breathhold examination (VIBE)-sequence. All removed colorectal lesions were evaluated by an experienced pathologist. RESULTS: CC confirmed 65 polyps less than 5 mm in diameter. Non of those lesions could be detected using MRC. Just two (4%) of the 49 removed lesions smaller than 5 mm showed signs of dysplasia. Additionally, CC confirmed 25 polyps between 6-15 mm in diameter (MRC 22). All those 25 lesions were removed in CC. Only four (16%) of those polyps showed signs of dysplasia and malignancy (11, 13, 13 and 15 mm). CONCLUSION: Dark-lumen MRC failed to detect all polyps smaller than 5 mm in diameter which are generally not clinically relevant at the moment of their detection and thus can be kept under surveillance. However, MRC as a non-invasive imaging modality is a promising alternative to CC in the detection of clinically relevant polyps larger than 5 mm in diameter.

Adult↗
PubMed1994

The effect of sulindac on colon polyps: circumvention of a transformed phenotype--a hypothesis.

Sulindac suppresses the growth of colon polyps in Gardner syndrome and familial adenomatous polyposis. The mechanism of action is not known. The problems are to ascertain the significance of high prostaglandin concentrations in transformed cells, colon polyps and cancers and to explain how sulindac restores normal growth patterns. A few clinical observations and an abundance of experimental data can be integrated to produce a reasonable model based on current biochemical and physiologic concepts. A fundamental defect in the formation of colon polyps is mutation of the APC (adenomatous polyposis coli) gene that leads to inadequate suppression of proliferation. There is high PGE2 content in colon polyps and cancers, presumably the result of stimulation by protein kinase C (PKC). In small quantities it stimulates cyclic AMP production but with persistent high concentrations it desensitizes and down-regulates specific PG receptors and inactivates adenylate cyclase, cAMP synthesis, and the cAMP-dependent mechanism for control of proliferation. The PKC pathway is thereby unopposed. It is hypothesized that restriction of PG synthesis by sulindac is accompanied by resensitization of PG receptors, and reactivation of the cAMP-dependent pathway for control of cell growth. It is further postulated that restoration of cAMP synthesis and protein kinase A activity converts a functionally inadequate mutant APC suppressor gene to one sufficient to inhibit colon polyp formation.

Colonic Neoplasms↗
PubMedDate not supplied

Diet and adenomatous polyp risk.

Studies of risk factors for colonic adenomatous polyps have been reported in greater numbers in 1993 than in all previous years combined. This explosion in interest in polyps has not arisen because polyps themselves cause serious illness. They are in the vast majority of cases asymptomatic. However, adenomas have become the surrogate for colon cancer in a number of phase III dietary intervention trials. These trials were undertaken at a time when very little was known of adenoma risk factors. Data accumulated in the past 18 months in general demonstrate a similarity in risk factors for cancer and polyp. Since it has also been recently established that polypectomy diminishes colon cancer risk, the adenomatous polyp has been established as an ethical and convenient surrogate for cancer of the colon. Prevention of colorectal cancer is the goal of all the above studies, and it is hoped that the dietary intervention trials currently under way will generate the data that will make prevention possible.

Adenomatous Polyps↗
PubMed2005

Segmentation and size measurement of polyps in CT colonography.

Virtual colonoscopy is a relatively new method for the detection of colonic polyps. Their size, which is measured from reformatted CT images, mainly determines diagnosis. We present an automatic method for measuring the polyp size. The method is based on a robust segmentation method that grows a surface patch over the entire polyp surface starting from a seed. Projection of the patch points along the polyp axis yields a 2D point set to which we fit an ellipse. The long axis of the ellipse denotes the size of the polyp. We evaluate our method by comparing the automated size measurement with those of two radiologists using scans of a colon phantom. We give data for inter-observer and intra-observer variability of radiologists and our method as well as the accuracy and precision.

Algorithms↗
PubMedDate not supplied

Clinical evaluation of gastric fundic gland polyps without familial polyposis coli.

BACKGROUND: Assessments were made of 63 cases of fundic gland polyposis (FGP) unassociated with adenomatosis coli. These cases were evaluated by radiological examination over 2 years follow-up. All polyps were pathologically confirmed by endoscopic biopsies. METHODS: Most cases were asymptomatic when diagnosed during mass radiological surveys of the upper gastrointestinal tract. The majority of patients ranged in age from 40-60 years, and the polyps numbered fewer than 20 in 55 cases (87.3%). Polyps were detected in the fundic glands using the congo red test and by biopsies. RESULTS: All serum gastrin values were within the normal range. During the course of this study, the polyps of 13 cases (20.6%) increased and those of three cases (4.8%) decreased or resolved completely. CONCLUSION: From these findings it is considered that FGP are observed in stomachs with less atrophy, and that polyps follow courses in which they increase, decrease, disappear, along with atrophy.

Adenomatous Polyposis Coli↗
PubMed1995

Appendiceal intussusception due to an appendiceal malignant polyp--an association in a patient with Peutz-Jeghers syndrome: report of a case.

A 40-year-old woman with Peutz-Jeghers syndrome and an appendiceal intussusception is reported. In this patient, the lead point was a large sessile, appendiceal polyp. The invaginated and inverted portion of the appendix resembled the long stalk of a pedunculated polyp on roentgenography and endoscopic examination. Histologically, the appendiceal polyp was a villous adenoma with mild to severe atypia and focal carcinoma in situ. In patients with Peutz-Jeghers syndrome, hamartomatous polyps and colorectal adenomatous polyps with highly malignant potential can coexist and must be managed appropriately. Therefore, when evaluating a polypoid or a pedunculated lesion in the cecal lumen, the possibility of an appendiceal intussusception should also be investigated.

Adenoma, Villous↗
PubMed1980

Histopathological Examinations of nasal polyps of different etiology.

A safe differentiation between allergic and non-allergic polyps appears impossible by means of light or electron microscopical examination of polyp tissue. There are some indications, however, which point to the allergic or non-allergic origin and it seems that the relationship between eosinophils and plasma cells with a low index is characteristic for polyps of allergic origin. Eosinophils and round-cell infiltrations are present in all types of polyps. An index of eosinophils to plasma cells below 5 is indicative for allergy and should induce the pathologist to give a hint to the clinican for allergological work-up. An index above 5 is more corresponding with infective etiology. Any changes of the basement membrane, i.e., smaller or larger gaps or even absence, are found only very irregularly and are not typical findings in either way. An increased number of glands and collagenic fibres, especially under the epithelium, are more an expression of the age of the polyp. Since the conservative therapy as mentioned above leads to good therapeutical results, it is desirable that an allergological work-up should be done in any case which shows the histological findings indicative for allergic etiology. Thus, repeated operations with all the risks and uncertain therapeutical benefit can be avoided.

Adolescent↗
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↗
PubMed1976

[The effect of 2,4-dinitrophenol, monoiodine acetate, sodium fluoride and hypoxia on the formation of plasma polyps in the placenta of guinea pigs (author's transl)].

Plasma polyps can be found at the end of a normal pregnancy. Following NaF and MJA-intoxication, there is an extreme increase of plasma polyps. This accelerated formation can be prevented by the injection of Na-pyruvate and often the number of polyps can be reduced below the norm. 2,4-Dinitrophenol intoxication and breathing of hypoxic gas mixture (2,5% O2, 5% CO2, 92,5% N2) do not lead to increased plasma polyp formation. This proves, that it is not hypoxia, not an energy deficit secondary to separation of oxydative phosphorylation and not cardiac insufficiency leading to secondary ischemia which are responsible for the extreme increase in the number of plasma polyps following the injection of MJA and NaF.

Acetates↗
PubMed1975

Benign lymphoid polyps of the rectum.

Benign lymphoid polyps are a rare histologic entity and should not be confused with malignant disease of the colon and rectum. Although retention polyps are the single most common type of colonic polyp in children, the presence of multiple clustered polyps in the rectum should alert the radiologist to the possibility of benign lymphoid polyps. A representative case is described and a review of the pediatric experience with this entity is discussed.

Child↗
PubMed1978

Gastric polyposis due to multiple hyperplastic adenomatous polyps.

Four cases of gastric polyposis in which the multiple polyps were hyperplastic adenomatous polyps are presented with endoscopic and histologic description. The multiple hyperplastic adenomatous polyps in our cases showed more diffuse involvement of specific regions of the stomach than is usual with papillary adenomatous polyps. Hyperplastic adenomatous polyps have a low potential for malignancy, and it is suggested that they may be followed by periodic observation rather than fulguration or removal.

Adenoma↗
PubMed1993

Massive hemobilia and acalculous cholecystitis due to benign gallbladder polyp.

A 37-year-old male with metachromatic leukodystrophy, a congenital cerebroside storage disease strongly associated with benign gallbladder polyps, presented with hemobilia and acalculous cholecystitis due to a long, slender, benign gallbladder polyp. This case report extends the clinical spectrum of gallbladder polyps and demonstrates a novel cause of hemobilia. The unusually long, slender polyp shape may have promoted hemorrhage due to the potential for torsion around a slender stalk. The mechanism of cholecystitis may have been cystic duct obstruction from blood clots or possibly from prolapse by the long, slender polyp into the cystic duct.

Adult↗
PubMed1988

Beta-endorphin-like immunoreactivity in normal mucosa, muscle layer, adenocarcinoma, and polyp of the colon.

beta-Endorphin-like immunoreactivity was detected in the mucosa and muscle layer of normal colon, adenocarcinomas derived from the colon mucosa, and colon polyps which were histologically confirmed to be adenoma without a focus of carcinoma or with in situ carcinoma. The contents of beta-endorphin-like immunoreactivity in adenocarcinomatous tissue (11.94 +/- 1.77 pmol/g wet wt) and colon polyps without focus of carcinoma (10.71 +/- 1.50 pmol/g wet wt) were found to be significantly higher than those in the mucosal layer (6.86 +/- 0.64 pmol/g wet wt) and muscle layer (8.30 +/- 0.68 pmol/g wet wt) of normal colon. These data suggest that the production of beta-endorphin-like immunoreactivity is specifically increased in some adenocarcinomas and adenomatous polyps and may be related to the alteration of bowel habits. Gel exclusion chromatography of beta-endorphin-like immunoreactivity revealed three peaks corresponding to beta-endorphin, beta-lipotropin, and an immunoreactive form between the two. In the mucosal layer and muscle layer of the colon, a broad major peak was eluted at the position of beta-endorphin, and minor peaks were eluted at the position of beta-lipotropin and between beta-endorphin and beta-lipotropin. In adenocarcinoma and polyp, the peak size corresponding to authentic beta-lipotropin was greater than that of beta-endorphin. This study demonstrated that beta-endorphin-like immunoreactivity existed at a high concentration in some colon adenocarcinomas and polyps whose elution patterns were different from those of normal colon tissue.

Adenocarcinoma↗
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↗
PubMed1988

The lost polyp: a guide to retrieval during colonoscopy.

Polyps resected during colonoscopy should be recovered and sent for pathologic examination. Unfortunately retrieval is incomplete ranging from 85-100% in reported series. There are several specific techniques aimed to increase the retrieval rate which in our experience amounted to 94.5% of a series of 182 polypectomies in 100 consecutive patients. All lost polyps were small and were thought to have been aspirated through the suction channel of the endoscope. In our study 10% of the initially "lost" polyps were within the instrument prior to cleaning. Various forms of polyp retrieval are reviewed with special attention to locating the aspirated polyp.

Colonic Polyps↗
PubMed1977

[In-vitro formation of plasma polyps in the human placenta and their isolation by means of "inverted centrifugation" (author's transl)].

1. Histological observations on sliced human placenta shaked in Krebs-Ringer-solution showed an high plasma polyp formation by the syncytiotrophoblast without any monoidoacetate or sodiumfluoride poisoning [1]. 2. The high plasma polyp formation of placenta slices incubated with gased (96% O2, 4% CO2) Krebs-Ringer-solution and shaked at 37 degrees C decreased rapidly and lasted up to 40 min. 3. Perfusion of the placenta intervillosum with fetal serum added Krebs-Ringer-Solution gave results in plasma polyp production up to six times higher than serum free Krebs-Ringer-solution perfusions. 4. Plasma polyp isolation and concentration by one step is discribed applying the inverted centrifugation technique: Plasma polyps migrate centripetally in Krebs-Ringer-solution containing 6% Ficoll (Pharmacia) and were concentrated in the tip of a tube invertedly placed into a swing-out-rotor.

Centrifugation↗