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PubMed1986

Polyp-simulating mucosal prolapse syndrome in (pre-) diverticular disease.

Eight patients with anal blood loss were referred for endoscopic polyp removal (4) or because of problems with the differential diagnosis (4). These patients were referred because of an apparent discrepancy between the initial diagnosis (malignancy, ulcerative colitis and hemangioma) and the clinical and/or radiographic and endoscopic findings. At endoscopy a polyp-simulating lesion was found in all patients; this was not adenomatous in nature, but was made up of bright red, hyperemic prolapsing redundant mucosa. Also, polypoid excrescences were present with a clearly distinguishable transition between the intensely red congested mucosa and the normal pink adjacent epithelium at the base of the stalk. The distribution of the lesions was confined to the sigmoid area. After institution of a fibre-enriched diet, regression of the lesions was documented. However, the conspicuous hypercontractility and thickening of the mucosal layer persisted. The clinical significance of the recognition of this polyp-simulating mucosal prolapse syndrome lies in the fact that endoscopic polyp removal is not indicated and that such abnormalities may be responsible for low-grade, chronic and recurrent bleeding.

Adult↗
PubMed1982

Adenocarcinoma occurring in a hyperplastic (metaplastic) polyp of the colon.

A case of adenocarcinoma occurring in a hyperplastic (metaplastic) polyp of the colon is presented. The polyp, two cm in diameter, was located in the transverse colon of a 45-year-old male patient, and was removed endoscopically. From the periphery to the centre, the polyp showed epithelial changes progressing from hyperplastic to severely dysplastic, terminating in a central focus of invasive adenocarcinoma. It is suggested that the considerable number of absorptive cells in large hyperplastic polyps may occasionally result in an excessive absorption of carcinogen thus leading to dysplastic changes.

Adenocarcinoma↗
PubMed1982

Transitional polyps of the colon.

Fourteen polps with the gross appearance of small hyperplastic (metaplastic) polyps, not exceeding five mm in diameter, were removed from the rectum and the sigmoid colon of patients during colonscopy, and from surgical specimens. At light microscopy they were seen to be composed of apparently normal mucosa. In most cases some hyperplastic (metaplastic) and adenomatous polyps were also present. HID-AB stain revealed the polyps to be composed of "transitional" mucosa containing almost exclusively sialomucins, in contrast to normal mucosa, in which sulphomucins predominate. It is suggested that these "transitional" polyps may represent a reservoir of hyperplastic (metaplastic) and adenomatous polps, the different fate depending on different environmental situations.

Colonic Neoplasms↗
PubMed1988

Common inheritance of susceptibility to colonic adenomatous polyps and associated colorectal cancers.

We studied 670 persons in 34 kindreds by flexible proctosigmoidoscopic examination (60 cm) to determine how frequently colorectal adenomas and cancers result from an inherited susceptibility. Kindreds were selected through either a single person with an adenomatous polyp or a cluster of relatives with colonic cancer. The kindreds all had common colorectal cancers, not the rare inherited conditions familial polyposis coli and nonpolyposis inherited colorectal cancer. Likelihood analysis strongly supported the dominant inheritance of a susceptibility to colorectal adenomas and cancers, with a gene frequency of 19 percent. According to the most likely genetic model, adenomatous polyps and colorectal cancers occur only in genetically susceptible persons; however, the 95 percent confidence interval for this proportion was 53 to 100 percent. These results suggest that an inherited susceptibility to colonic adenomatous polyps and colorectal cancer is common and that it is responsible for the majority of colonic neoplasms observed clinically. The results also reinforce suggestions that first-degree relatives of patients with colorectal cancer should be screened for colonic tumors. This evidence of an inherited susceptibility to a cancer with well-recognized environmental risk factors supports the hypothesis that genetic and environmental factors interact in the formation and transformation of polyps.

Adenomatous Polyposis Coli↗
PubMed2002

Treatment with argon plasma coagulation reduces recurrence after piecemeal resection of large sessile colonic polyps: a randomized trial and recommendations.

BACKGROUND: Recurrence is frequent after piecemeal snare resection of large sessile colorectal polyps. The aim of this study was to evaluate the safety and efficacy of argon plasma coagulation (APC) in preventing recurrence when applied to the edge and base of the polypectomy site after apparently complete piecemeal resection. METHODS: Patients with large (>1.5 cm) sessile polyps removed by piecemeal snare cautery were placed into 2 groups. The first consisted of patients with polyps believed by the endoscopist to be completely excised. These patients were randomized to either no further therapy (control) or to APC of the rim and any residual mucosal or submucosal tissue in the base of the polypectomy site. The second group comprised patients in whom polyps, as judged by the endoscopist, were incompletely excised by snare polypectomy; APC was routinely applied without randomization to all visible remaining adenomatous tissue. Follow-up colonoscopy was performed within 3 months and 1 year; biopsy specimens were taken routinely from the resection site and further polypectomy was performed as indicated. RESULTS: There were fewer recurrences after APC in the randomized group (1/10 APC, 7/11 no APC; p = 0.02). In the group with initial incomplete snare polypectomy, recurrence was detected at 3 months in 6 of 13 despite APC. One patient was hospitalized with abdominal pain and minor rectal bleeding but required no intervention. There were no other episodes of significant late bleeding caused by piecemeal polypectomy. One patient was referred for surgery after unsuccessful endoscopic management. CONCLUSIONS: In patients with apparent complete endoscopic snare resection of large adenomas, postpolypectomy application of APC reduces adenomatous recurrence.

Aged↗
PubMed2002

Aspirin-sensitive versus non-aspirin-sensitive nasal polyp patients: analysis of leukotrienes/Fas and Fas-ligand expression.

OBJECTIVE: The goal of the present study was to identify levels of leukotrienes released by leukocytes and nasal polyps from aspirin-sensitive patients (ASPs) and non-aspirin-sensitive patients (NASPs) after exposure to various concentrations of aspirin. Eosinophil expressions of apoptosis regulators were also compared. STUDY DESIGN AND SETTING: Leukotriene release from nasal polyps and leukocytes of ASPs and NASPs was measured after exposure to differing concentrations of aspirin. Eosinophils were analyzed for Fas and Fas ligand receptors using flow cytometry. RESULTS: NASPs showed increased leukotriene release from nasal polyps on increased aspirin exposure. Polyps from ASPs did not show any change. ASPs showed greater leukotriene release from blood on increasing aspirin exposure compared with NASPs. Flow cytometric analysis showed eosinophils in the peripheral blood of ASPs have decreased Fas expression compared with those of NASPs. CONCLUSIONS: This study showed differences in leukotriene release and eosinophil apoptosis between ASPs and NASPs. SIGNIFICANCE: These findings suggest a role of leukotrienes and eosinophils in aspirin sensitivity mechanisms in blood.

Adult↗
PubMed2005

Microcomputed tomography colonography for polyp detection in an in vivo mouse tumor model.

This study was initiated to evaluate the efficacy of negative contrast-enhanced microcomputed tomography (microCT) colonography for the noninvasive detection of colonic tumors in living mice. After colonic preparation, 20 anesthetized congenic mice were scanned with high-resolution microCT. Images were displayed by using commercial visualization software and interpreted by two gastrointestinal radiologists, who were unaware of tumor prevalence and findings at gross pathology. Two-dimensional multiplanar images were assessed by using a five-point scale to distinguish colonic tumors (polyps) from fecal pellets (5 = definitely a tumor, 4 = probably a tumor, 3 = indeterminate, 2 = probably not a tumor, 1 = definitely not a tumor). Gross pathologic evaluation of excised mouse colons served as the reference standard. Data analysis included dichotomizing results, with 1-2 indicating no tumor and 3-5 indicating tumor and also receiver operator characteristic curve analysis with area under the curve for threshold-independent assessment. A total of 41 colonic polyps in 18 of the 20 mice were identified at gross examination on necropsy, of which 30 measured 2-5 mm and 11 measured <2 mm in size. The pooled per-polyp sensitivity for lesions >2 mm was 93.3% (56/60). The pooled per-mouse sensitivity for polyps >2 mm was 97.1% (33/34). Pooled specificity for distinguishing fecal pellets from tumor was 98.5% (65/66). The combined area under the curve from receiver operator characteristic curve analysis was 0.810 +/- 0.038 (95% confidence interval, 0.730-0.890). These findings indicate that accurate noninvasive longitudinal monitoring of colon tumor progression or response to various therapies is now technically feasible in live mice by using this microCT colonography method.

Animals↗
PubMed2005

Concurrent suppression of hyperlipidemia and intestinal polyp formation by NO-1886, increasing lipoprotein lipase activity in Min mice.

We have previously reported a hyperlipidemic state in two strains of Apc-deficient mice, Min and Apc(1309), associated with low expression levels of lipoprotein lipase (LPL) in the liver and small intestine, and enforced induction of LPL mRNA by peroxisome proliferator-activated receptor (PPAR)alpha and PPARgamma agonists clearly suppressed hyperlipidemia and intestinal polyp formation in these mice. Meanwhile, a compound, NO-1886, has been shown to increase LPL mRNA and protein levels but not to possess PPARalpha and PPARgamma agonistic activity. In this study, therefore, the effects of NO-1886 on hyperlipidemia and intestinal polyp formation were investigated in Min mice. Administration of 400 and 800 ppm NO-1886 in the diet for 13 weeks from 7 weeks of age caused a reduction of serum triglycerides to 39% and 31% of the untreated value, respectively, and the values for very low-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol were improved almost to the wild-type level with a corresponding elevation of the LPL mRNA. Moreover, total numbers of intestinal polyps in the groups receiving NO-1886 at 400 and 800 ppm were decreased to 48% and 42% of the control value, respectively. We also found that NO-1886 suppressed cyclooxygenase-2 transcriptional promoter activity in a reporter gene assay and reduced cyclooxygenase-2 mRNA levels in the small intestine of Min mice. These results indicate that suppression of serum lipid levels by increasing LPL activity may contribute to a reduction of intestinal polyp formation with Apc-deficiency, and NO-1886 and its derivatives could be useful as chemopreventive agents for colon cancer.

Animals↗
PubMed1997

Histochemical study of the epithelia of nasal polyps by biotinylated lectins and neoglycoprotein. A comparison with the normal human respiratory epithelium.

Formalin-fixed, paraffin-embedded sections from human nasal polyps and the normal respiratory epithelium were glycohistochemically investigated. Three biotinylated lectins were used: peanut (Arachis hypogaea) agglutinin (PNA) which, binds to terminal galactose (beta 1-3) N-acetylgalactosamine residues that can be unmasked by a neuraminidase digestion; wheat germ (Triticum vulgare) agglutinin (WGA), which binds to N-acetylglucosamine and N-acetylneuraminic acids; and gorse seed (Ulex europaeus) agglutinin (UEA-1), which binds to L-fucose. In addition, the presence of accessible galactose (beta 1-3) N-acetylgalactosamine (T-antigen) glycan receptors (endolectins) was also assessed. The avidin-biotin-peroxidase complex (ABC) and diaminobenzidine (DAB) were used as chromogen. The ciliated cells of the normal respiratory epithelium and those of the pseudostratified epithelium of nasal polyps possess similar glycohistochemical characteristics suggesting no major alterations on the level of lectin-reactive carbohydrate epitopes as indicators of cellular glycosylations. Notably, this parameter can respond sensitively to changes in cell differentiation or activation. The basal and mucus-secreting cells in the two epithelia display different reactivity patterns emphasizing the presence of dissimilar sugar residues. Similarly, the dysplasia reflecting squamous epithelium of nasal polyps shows a distinct staining behaviour, indicative for disparate glycoconjugate display. Thus, quantitative differences in the lectin-selective staining of various cell types are detectable. The expression of T-antigen-bearing neoglycoprotein binding is weak and similar in both the normal epithelium and the pseudostratified epithelium lining nasal polyps. Only the most superficial cells of the squamous epithelium disclose a moderate labelling with this probe. These results indicate that further studies in this field are warranted, employing neoglycoproteins and also endolectins from human tissues to correlate glycobiological properties of the epithelium of the conducting airways and its diseased forms with functional features.

Adult↗
PubMed2000

Effect of penicillin on experimental acute otitis media. A histopathological study of goblet cell density, bone modelling dynamics, polyp and adhesion formation.

Clinical studies have shown that the effect of antibiotic treatment on acute otitis media is modest. Experimental acute otitis media induces a number of histopathological changes in the middle ear mucosa. Among these are increased goblet cell density, polyp and adhesion formation, as well as massive osteoneogenesis. To investigate the effect of penicillin administration on these histopathological features, we employed a rat model of acute pneumococcal otitis media. Five of 25 rats were sacrificed on days 4, 8, 16, 90 and 180 post-inoculation, preceded by oral administration of penicillin V 100 mg/kg/day, initiated on day 2 and lasting 5 days. Using a light microscope, qualitative and quantitative histopathology of middle ear goblet cell density, bone-modelling dynamics, polyp and adhesion formation was registered and compared with previous studies of untreated animals. Increase in goblet cell density and new bone formation was reduced significantly by treatment, whereas polyp and adhesion formation was unaffected by penicillin administration. It is concluded that penicillin reduces middle ear secretory capacity and new bone formation during and following acute otitis media, conceivably preventing subsequent development of secretory otitis media, leaving polyp and adhesion formation unchanged.

Acute Disease↗
PubMed2000

Effect of intranasal treatment with capsaicin on the recurrence of polyps after polypectomy and ethmoidectomy.

The aim of this study was to evaluate the influence of five intranasal applications of capsaicin, performed after endoscopic polypectomy associated with partial middle turbinectomy and anterior ethmoidectomy, on the recurrence of nasal polyps and the intensity of nasal obstruction and rhinorrhea. Fifty-one patients (19 females, 32 males, mean age 43 years) suffering from nasal polyposis for more than 1 year were included in this double blind, randomized, placebo-controlled study. During post-surgical controls, local anaesthesia and vasoconstriction of the middle meatus area were performed in all patients with a cotton pellet soaked with lidocain and adrenaline. In 29 patients, the same type of cotton pellet soaked with capsaicin (3 x 10(-6) mol. dissolved in 70% ethanol) was left into the middle meatus of both nostrils for 20 min. As a control group, 22 patients, matched for age and sex, were treated with the capsaicin vehicle alone (70% ethanol). All patients studied received the intranasal treatment once a week for 5 weeks. Subjective evaluations of nasal airway resistance (NAR) and rhinorrhea were recorded by means of a visual analogue scale. Clinical staging of the nasal polyposis (graded from stage 0 = absence of polyp to stage 3 = polyps occupying the entire nasal cavity) was evaluated by the same ENT specialist (ZW) using a 0 degrees endoscope. All parameters were recorded for each patient 1 week before surgery, then once a month for 9 months. Patients treated by endoscopic surgery followed by intranasal capsaicin application, reported a marked reduction in their NAR compared with the pretreatment evaluation (p<0.001). In contrast, patients treated with the vehicle alone did not have any significant improvement of their subjective NAR. Subjective rhinorrhea was not modified by either treatment. Patients treated with capsaicin showed a significant smaller staging of their nasal polyposis compared with the control group (p<0.001). These observations suggest that endoscopic surgery followed by intranasal capsaicin application reduces polyps and nasal obstruction recurrence and could be an alternative treatment to expensive corticosteroids in developing countries.

Administration, Intranasal↗
PubMed2005

Glycosoaminoglycans in nasal polyps.

CONCLUSION: The qualitative and quantitative compositions of GAGs were comparable in all the polyps examined. OBJECTIVE: Glycosoaminoglycans (GAGs) are an integral component of proteoglycans, which are constituents of connective tissue. The qualitative and quantitative compositions of GAGs occurring in proteoglycans determine their biological role. In this work, individual fractions of GAGs occurring in nasal polyps were isolated and estimated. MATERIAL AND METHODS: Polyps were obtained over a 2-year period from 31 patients (18 males, 13 females; age range 28-70 years) who underwent polypectomy and evaluated using routine histopathology. RESULTS: The amount of hyaluronic acid in nasal polyps was high, the amounts of dermatane sulphate and chondroitine-6-sulphate were slightly lower and the amounts of chondroitine-4-sulphate, heparin, heparan sulphate and keratan sulphate were the lowest.

Adult↗
PubMed2003

Induction of apoptosis in nasal polyp fibroblasts by glucocorticoids in vitro.

OBJECTIVE: To examine the possible mechanisms underlying the therapeutic mode of action of glucocorticoids (GCs) in nasal polyposis. MATERIAL AND METHODS: The effects of GCs on nasal polyps were firstly evaluated by examining the growth of fibroblasts derived from 10 nasal polyps in vitro. Subsequently, the ability of GCs to induce apoptotic cell death in fibroblasts was examined. RESULTS: Addition of betamethasone 21-phosphate (BET) at a concentration of > 1 x 10(-3) M to cell cultures inhibited cell growth in all cases examined. BET and dexamethasone 21-phosphate, but not testosterone or estradiol, caused apoptotic cell death in 2/10 nasal polyp fibroblasts, as assessed by agarose gel electrophoresis, when the cells were cultured with the agents for > 96 h. The minimum concentration of agent needed to cause apoptosis was 1 x 10(-3) M, which is half of the recommended therapeutic dose. CONCLUSION: The present findings suggest that topical application of GCs in nasal polyposis patients suppresses proliferation of fibroblasts in polyps and results in favorable modification of the clinical status of these patients.

Adult↗
PubMed1998

Comparative assessment of cell proliferation and accumulation of extracellular matrix in nasal polyps.

In nasal polyps constantly associated with chronic inflammation, a dysregulation of epithelial cell proliferation has been described. Involvement of extracellular matrix accumulation is also suggested in the formation and growth of nasal polyps. In this study, we attempted to evaluate the activity of the proliferation of epithelial cells and fibroblasts and the relation between fibronectin accumulation and these cell proliferations in nasal polyps. The pathological specimens of 30 patients were examined which manifested proliferating cell nuclear antigen (PCNA) expression in epithelial cells and fibroblasts and in fibronectin expression. PCNA expression was quantified by calculating the index for each sample. No significant difference in PCNA index was found between epithelial cells and fibroblasts. However, a significant correlation was found between the epithelial and fibroblastic PCNA index. In addition, fibronectin immunopositivity was well correlated with the activity of proliferation of fibroblasts. Therefore, proliferation of fibroblasts is also an important factor in the growth of nasal polyps, and its relationship with fibronectin accumulation may play a role in the pathogenesis of nasal polyposis.

Adult↗
PubMed1998

Expression of intercellular adhesion molecule-1 on the vascular endothelium in nasal polyps before, during and after topical glucocorticoid treatment.

Nasal polyposis is a result of a chronic inflammatory disorder in the upper airways. In vitro studies have revealed that extravasation of leucocytes requires interactions between several sets of adhesion molecules expressed on the circulating leucocytes and the vascular endothelium. Therefore, the endothelial expression of intercellular adhesion molecule-1 (ICAM-1) in biopsies from polyps and inferior turbinates was investigated by the use of immunohistochemical staining. Biopsies were obtained from 11 patients suffering from nasal polyposis before, during and after treatment with 100 microg budesonide (Rhinocort Turbuhaler) in each nostril twice daily. Before, during and after treatment, ICAM-1 was expressed in the majority of vessels in polyps and mucosa of inferior turbinates. The intensity of endothelial ICAM-1 expression in polyps was significantly reduced during topical glucocorticoid treatment compared with the pretreatment and posttreatment levels (p < 0.005). In biopsies from the inferior turbinates, the intensity of the endothelial ICAM-1 expression was lower during treatment than after discontinuation of medical treatment (p < 0.005). In conclusion, topical budesonide treatment seems to downregulate ICAM-1 expression on the vascular endothelium in nasal polyps. Such an effect may interfere with leucocyte extravasation and partially account for the anti-inflammatory effect of local glucocorticoid treatment in human nasal polyposis.

Administration, Topical↗
PubMed1992

Polyps in the colon. Answers to key questions.

Adenomatous polyps in the adult colon and rectum are of great clinical importance because they can undergo malignant degeneration. Size and histologic type are useful in predicting the likelihood of malignancy. In most cases, biopsy is required to distinguish small adenomas (< 1 cm) from hyperplastic polyps, which do not undergo malignant degeneration. An adenomatous polyp found during proctosigmoidoscopy warrants total colonoscopy with polypectomy, because of the possibility of a synchronous adenoma or cancer. Periodic colonoscopic follow-up is advised, because of the high rate of recurrent ("metachronous") adenomas. The optimal screening technique for colorectal polyps and early cancer in the general population remains to be defined. The most commonly used program at present entails periodic fecal occult blood testing and flexible proctosigmoidoscopy. Diets high in fiber and low in fat may have protective effects against the development of colonic neoplasms.

Adenoma↗
PubMed1997

Immunomodulatory effect of beta-carotene on T lymphocyte subsets in patients with resected colonic polyps and cancer.

Results from a number of studies suggest that beta-carotene-containing foods prevent the initiation or progression of various cancers. One possible mechanism for this effect could be enhancement of the immune response. The aim of this study was to determine whether beta-carotene modulates T lymphocyte subsets in patients affected with colonic polyps or cancerous lesions. Patients with previous adenomatous colonic polyps (n = 18) or colon cancers (n = 19) were randomized to receive placebo or beta-carotene (30 mg/day) for three months. Percentages of T lymphocyte subsets were determined using flow cytometry in blood samples collected before randomization and at three months. T lymphocyte subsets of 14 normal control subjects were also determined for comparison. Initially, there was no difference in total leukocyte counts, percentage of lymphocytes, and various subsets of lymphocytes among the three groups, although in cancer patients there was a lower percentage of CD4 and interleukin-2 (IL-2) receptor-positive (IL-2R+) cells than in patients with polyps and in controls. After supplementation with beta-carotene, a significant increase in IL-2R+ T lymphocytes (from 12.7 +/- 3.0% to 26.0 +/- 1.9%) and CD4+ lymphocytes (from 40.9 +/- 3.1% to 45.6 +/- 3.2%) was seen only in the cancer patients. These percentages remained unchanged in patients with adenomatous polyps receiving placebo or beta-carotene. We concluded that beta-carotene increased the number of IL-2R+ T lymphocytes and CD4+ lymphocytes, which in turn may produce IL-2 only in patients with cancer who may already have some deficiency in their immune system. This increase in activated T lymphocytes may mediate cytotoxic reactions to cancer cells via cytokine production.

Adult↗
PubMed2004

Effect of previous hormone replacement therapy on endometrial polyps during menopause.

The aim of this study was to evaluate the effect of hormone replacement therapy (HRT) on the expression of Ki-67, bcl-2 and c-erb.B2 in endometrial polyps during menopause. Sixteen patients using HRT and 24 untreated controls with endometrial polyps were enrolled in this study. Polypectomy was carried out by hysteroscopy. The presence of c-erb.B2, bcl-2 and Ki-67 expression was determined by immunohistochemistry. HRT was found to decrease Ki-67 and bcl-2 expression in endometrial polyps without affecting the c-erb.B2 staining reaction. HRT may cause endometrial polyp involution by decreasing proliferation and stimulating apoptosis.

Administration, Cutaneous↗