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PubMedDate not supplied

Diagnosis and management of gastrointestinal polyps: pediatric considerations.

Painless, bright red, rectal bleeding with normal stool frequency and consistency is the hallmark presentation of colorectal polyps at any age. Most polyps in children are sporadic, usually isolated, colorectal juvenile polyps that do not require any further surveillance after they are removed. There is, however, increasing recognition of syndromes, including familial adenomatous polyposis, juvenile polyposis coli, Peutz-Jeghers syndrome, and infrequent conditions, such as PTEN hamartoma and hereditary mixed polyposis syndromes. The aim of this review is to allow the reader to correctly identify the patients who do not require follow-up and the smaller group of patients who do require follow-up because of syndromic polyp conditions.

Adenomatous Polyposis Coli↗

PubMed2001

Recurrent atypical myxoid fibroepithelial polyp associated with vulvar Crohn's disease.

Fibroepithelial polyps of the lower female genital tract are common lesions that can rarely exhibit atypical features including increased and atypical mitoses, bizarre nuclei, and hypercellularity, a combination of findings that may suggest malignancy. Five recurrent cases have been published to date, two of which were in pregnant females; the other three followed incomplete excisions. Our case is that of a 25-year-old female with Crohn's disease who developed multiple recurrences of polypoid and domed lesions of the labium minus following surgical excision. Histologic findings in the initial and recurrent lesions were consistent with atypical myxoid fibroepithelial polyps with underlying vulvar Crohn's disease. The lesions subsequently improved with standard Crohn's treatment including 5-amino-salicylic acid (Pentasa) and prednisone. The present case represents the only example of this entity associated with Crohn's disease, and it is the only reported recurrent case not associated with pregnancy, tamoxifen administration, or positive excision margins. The clinical, microscopic, and immunohistochemical findings of this case suggest that atypical fibroepithelial polyps of the lower female genital tract, cutaneous pleomorphic fibroma, and lesions such as fibroepithelial polyps of the anus may represent variants of the same atypical reparative process.

Adult↗

PubMedDate not supplied

Automated segmentation of colonic walls for computerized detection of polyps in CT colonography.

PURPOSE: A new method for fully automated segmentation of the colonic walls in volumetric CT data was developed for limitation of the search space in computerized detection of polyps. METHOD: For reliable segmentation, an anatomy-oriented approach was used, in which several anatomical structures are segmented in addition to the colon for utilization of their properties. RESULTS: The segmentation method was validated by use of 14 data sets, consisting of cases positive for colonic polyps. We found that the segmented colonic walls included all of the polyps. A subjective rating of the results was performed based on several criteria for visualization of anatomic detail of the colonic wall and mucosal surface. Except for a few cases in which insufflation of the colon was insufficient, all of the results included >95% of the colonic walls. CONCLUSION: This method for colonic wall segmentation is reliable and the segmentation results are applicable in both visualization of the colon and computer-aided diagnosis in the detection of polyps in CT colonography.

Automation↗

PubMedDate not supplied

Automated knowledge-guided segmentation of colonic walls for computerized detection of polyps in CT colonography.

PURPOSE: We have developed a novel automated technique for segmenting colonic walls for the application of computer-aided polyp detection in CT colonography. In particular, the technique was designed to minimize the presence of extracolonic components, such as small bowel, in the segmented colon. METHODS: The segmentation technique combines an improved version of our previously reported anatomy-oriented colon segmentation technique with a colon-based analysis step that performs self-adjusting volume-growing within the colonic lumen. Extracolonic components are eliminated by intersecting of the resulting two segmentations, so that the colonic walls remain in the intersection. The technique was evaluated on 88 CT colonography datasets. The colon segmentations were evaluated subjectively by four radiologists, as well as objectively by performance of an automated polyp detection on the segmentation. For comparison, the tests were also performed for the anatomy-oriented colon segmentation technique. RESULTS: On average, the technique covered 98% of the visible colonic walls. Approximately 50% of the extracolonic components remaining in the anatomy-oriented segmentation were removed, but 10-15% of the segmentation still contained extracolonic components. The dataset-based false-positive rate of the automated polyp detection was improved by 10% without compromising the 100% case-based sensitivity, and the case-based false-positive rate was improved by 15% over the previous false-positive rate. CONCLUSIONS: The technique segments practically all of the colonic walls in the region of diagnostic quality with a large reduction in the amount of extracolonic components over our previously used technique. The new segmentation improves the specificity of our computer-aided polyp detection scheme significantly without any degradation in detection sensitivity.

Artificial Intelligence↗

PubMed1999

The small polyp at flexible sigmoidoscopy: an historical perspective on why practices still vary.

Current practices vary regarding the approach to small polyps discovered during screening flexible sigmoidoscopy. The most common practice is to perform colonoscopy whenever any adenoma is detected, a strategy that generally uses biopsy of polyps < or = 5 mm in size. However, data suggest that tubular adenomas < 1 cm in size in the distal colon have less predictive value than other distal adenomas for advanced adenomas in the proximal colon. Thus, some centers reserve colonoscopy for distal adenomas with tubulovillous or villous histology, > 1 cm in size, or with high-grade dysplasia. At the other end of the spectrum, another school of thought advocates screening colonoscopy, recognizing that most patients with advanced proximal adenomas do not have polyps in their distal colon. Advocates of this approach use any excuse to perform colonoscopy, whether it be a positive fecal occult blood test, minor symptoms, or small polyp at flexible sigmoidoscopy, even if hyperplastic. This review describes the history of the controversy regarding management of findings at flexible sigmoidoscopy, the data pertinent to the controversy, and the basis for the three approaches described above, all of which are currently within the standard of medical care.

Colonic Polyps↗

PubMed1985

Lymphoid polyps of the rectum.

In children lymphoid polyps of the rectum are uncommon benign lesions with a good prognosis following local treatment. We report a girl in whom a cluster of lymphoid polyps occurred 9 months following removal of a single lymphoid polyp. All of the polyps, including the original lesion, displayed a monoclonal nature on immunocytochemical examination.

Child↗

PubMed1999

Do corticosteroids induce apoptosis in nasal polyp inflammatory cells? In vivo and in vitro studies.

OBJECTIVE/HYPOTHESIS: Corticosteroids are an effective treatment for nasal polyposis. The exact mechanism of action is not certain. Recent research demonstrates that apoptosis (programmed cell death) in inflammatory cells is an important factor in the resolution of inflammation, and apoptosis is induced in eosinophils in cell culture with steroids. We hypothesized that inflammatory cell apoptosis is a key feature of regression of nasal polyps on exposure to steroids and examined this hypothesis in vivo and in vitro. METHODS: A double-blind, placebo-controlled pilot study of fluticasone propionate aqueous nasal spray (FPANS) in nasal polyposis in humans in vivo was undertaken, and the effect of treatment on indices of cell death and proliferation measured. In addition, explants of nasal polyp tissue were maintained in vitro in short-term tissue culture with dexamethasone at increasing doses (0.1-50 micromol) over varying time intervals and then analyzed for similar indices of proliferation and cell death. RESULTS: Apart from a marginal increase in apoptotic:mitotic ratio in epithelium, little difference between the effect of FPANS and placebo was demonstrated in vivo. However, in vitro, apoptotic index was significantly increased in the stromal layers in relation to time of incubation (P = .0169), and a significant dose-response relationship was demonstrated at 24 hours between stromal cell apoptosis and dexamethasone concentration (P = .001). Eosinophil apoptosis was confirmed by in situ end labeling and transmission electron microscopy. No steroid or time effect on epithelial cells was demonstrated in vitro. CONCLUSION: Corticosteroids induce apoptosis in inflammatory cells in human nasal polyps in vitro. This is not reflected by a similar response to FPANS at 14 days in vivo, but may still play a part in regression of polyps with other forms of administration or at other time points.

Administration, Topical↗

PubMed2003

Local production of Aspergillus fumigatus specific immunoglobulin E in nasal polyps.

BACKGROUND: Aspergillus spp. play a significant role in the etiology of immunoglobulin (Ig)E mediated allergic fungal sinusitis (AFS). It is unclear whether Aspergillus spp. are also involved in nasal polyps without the characteristic clinical features of AFS. OBJECTIVES: The frequency of Aspergillus spp. and Aspergillus-specific IgE in nasal lavages and serum of patients with severe nasal polyps (n = 33) without clinical features of AFS should be investigated. STUDY DESIGN: Prospective study. METHODS: An aliquot of nasal lavage fluid was treated with dithiothreitol and examined for Aspergillus fumigatus by culture and an Aspergillus-specific polymerase chain reaction (PCR) assay. An additional aliquot of nasal fluid and serum of the same patient were tested for specific IgE (Unicap, Pharmacia, Freiburg, Germany) to recombinant Aspergillus fumigatus allergen (rAspf) 1 to 6. RESULTS: All patients had negative skin prick tests for Aspergillus fumigatus. Four of 33 (12%) lavage samples were positive for Aspergillus spp. by PCR. In one of these samples, rAspf-specific IgE was detected but none in the serum. Nasal lavage and serum samples of the remaining 29 patients were negative for rAspf-specific IgE. CONCLUSIONS: Aspergillus spp. detection is rare in patients with severe nasal polyps without characteristic clinical features of AFS. Specific IgE in nasal secretions may be elevated in patients with negative skin prick tests and serum IgE. In these cases, immunologic mechanisms similar to AFS may be involved. Fungal etiology has been proposed to underlie severe nasal polyps in general. However, Aspergillus spp. seem not to play a significant role.

Allergens↗

PubMed2001

Do undesirable effects of screening affect all-cause mortality in flexible sigmoidoscopy programmes? Experience from the Telemark Polyp Study 1983-1996.

There is substantial evidence for the beneficial effect of screening programmes aimed at reducing mortality from colorectal cancer (CRC). The effect on all-cause mortality, however, may not necessarily be beneficial. In the present study we used the follow-up results 13 years after a flexible sigmoidoscopy screening to evaluate the long-term effects of informing participants about findings at flexible sigmoidoscopy (FS) screening. There were no severe complications and there was no long-term difference in deaths related to whether there had been any mucosal rupture (biopsy or snare resection) or not. As a group, those who attended in 1983 and were informed that they had polyps tended to improve their smoking habits more than those informed that they had no polyps. Similarly, and in spite of more people giving up smoking, the group with polyps had a trend towards a smaller increase in BMI (+0.7 (95% CI 0.2-1.1)) than the polyp-free group (+1.2 (95% CI 0.9-1.6)) (P = 0.07). The observations suggest that flexible sigmoidoscopy screening may face an educational challenge to avoid unfavourable changes in the lifestyle of screenees, an effect that may more than outweigh the beneficial effect of screening.

Colonic Polyps↗

PubMed2005

Polyps in the exstrophic bladder. A cause for concern?

PURPOSE: The role of environmental injury in carcinogenesis is widely recognized. Malignancy in exstrophic bladders has been reported most frequently in untreated adults and those undergoing surgical treatments which involve the mixing of fecal and urinary streams. The question of whether the closed exstrophic bladder has a similar potential for malignancy has not been resolved. The polypoid appearance of the exstrophic bladder template raises the concern of premalignant lesions. We characterized the histology of these lesions and analyzed their microscopic features with particular reference to predisposition for dysplasia. In doing so, we attempt to address the aforementioned question and set the stage for definitive quantification of the risk of malignancy in these patients with careful, long-term followup. MATERIALS AND METHODS: Under institutional board review, the slides of 38 patients with classic bladder exstrophy who had polyps excised at the time of closure were reviewed by a single genitourinary pathologist (JIE). The most common findings were reported for polyps resected at primary and secondary closure, respectively, and a comparative analysis was performed. RESULTS: Of the 38 cases 24 were primary closures and 14 were secondary closures. Six of the primary closures were delayed by 6 weeks or greater. The 2 basic types of polyps observed were fibrotic and edematous. Both types were associated with overlying reactive squamous metaplasia in approximately 50% of cases. Varying degrees of fixed on file Brunn's nests, cystitis cystica and cystitis glandularis were noted. Cystitis glandularis was observed in a significantly greater percentage of secondary closures (p = 0.0014). CONCLUSIONS: Although no dysplasia was noted, cystitis glandularis is associated with the development of adenocarcinoma of the bladder. The finding of cystitis glandularis suggests a more severe epithelial injury and it follows that the significant majority of these cases (10 of 14, 71.4%) were observed with polyps resected during secondary closure. These patients warrant future surveillance with urine cytology and cystoscopy as they enter adult life.

Bladder Exstrophy↗

PubMed2003

Metastatic breast lobular carcinoma involving tamoxifen-associated endometrial polyps: report of two cases and review of tamoxifen-associated polypoid uterine lesions.

Two cases of lobular breast carcinoma metastatic to an endometrial polyp are described. Both patients had been treated with tamoxifen and presented with abnormal uterine bleeding. Histology of endometrial biopsy in both cases showed typical tamoxifen-associated endometrial polyps with focal subtle stromal infiltration by metastatic lobular breast carcinoma. This was confirmed by positive immunohistochemical staining with cytokeratin epithelial markers. Metastatic breast carcinoma may rarely involve tamoxifen-associated endometrial polyps. Because primary endometrial carcinomas may also arise within tamoxifen polyps, these should be extensively sampled. We briefly review polypoid uterine lesions that may occur secondary to tamoxifen therapy.

Antineoplastic Agents, Hormonal↗

PubMedDate not supplied

Computed tomography colonography: automated diameter and volume measurement of colonic polyps compared with a manual technique--in vitro study.

OBJECTIVE: To investigate inter- and intraobserver agreement of automated measurement of polyp diameter in vitro. METHODS: Two phantoms ("QRM" and "Whiting") containing simulated polyps of known diameter and volume were scanned using 16-detector row computed tomography. Two observers estimated polyp diameter using 3 methods: software calipers ("manual"), freehand boundary identification ("semiautomatic"), and automated software segmentation ("fully automatic"). RESULTS: Intraobserver 95% limits of agreement for diameter were narrowest for the fully automatic method (QRM span: 0.39 mm, 0.48 mm; Whiting span: 0.24 mm, 0 mm). Manual estimates were approximately 10 times wider (QRM span: 3.57 mm, 3.21 mm; Whiting span: 3.2 mm, 2.02 mm). Volume estimates were narrowest for the fully automatic method (span: 24.2 mm, 24.1 mm vs. 97.9 mm, 102.9 mm for semiautomatic measurement). Interobserver agreement for diameter was narrowest for the fully automatic method (QRM span: 0.12 mm, Whiting span: 0.16 mm), with the manual method approximately 18 times wider (QRM span: 2.87 mm, Whiting span: 2.18 mm). CONCLUSION: Fully automated measurement of polyp diameter and volume is technically feasible and results in superior inter- and intraobserver agreement.

Colonic Polyps↗

PubMed2026

Endoscopic mucosal resection with precutting vs. anchoring technique using snare tip for 10-25 mm nonpedunculated colorectal polyps: a randomized controlled trial.

BACKGROUND AND AIMS: Modified endoscopic mucosal resection (EMR) techniques using a snare tip, precutting EMR (P-EMR) and anchoring EMR (A-EMR), have been developed for the effective resection of nonpedunculated colorectal polyps measuring 10-25 mm. Although previous studies have compared either P-EMR or A-EMR with conventional EMR, no study has directly compared these two snare tip-assisted techniques within modified EMR. This study aimed to evaluate P-EMR and A-EMR in terms of the R0 resection rate and procedure duration. METHODS: This prospective randomized controlled trial enrolled patients with nonpedunculated colorectal polyps measuring 10-25 mm. The patients were randomly assigned to the P-EMR or A-EMR groups. The primary outcome was R0 resection rate, defined as en bloc resection with histologically tumor-free margins. Secondary outcomes included the injection-to-snaring time, total procedure time, and adverse events. RESULTS: Each group included 63 polyps, of which 126 were analyzed in the final evaluation. Both groups achieved high R0 resection rates (93.7% for P-EMR and 88.9% for A-EMR), with no significant difference ( P  = 0.344). However, the A-EMR group demonstrated significantly shorter injection-to-snaring time (181.8 ± 81.9 vs. 320.9 ± 143.5 s, P  < 0.001) and total procedure time (259.7 ± 139.7 vs. 479.8 ± 249.0 s, P  < 0.001). Adverse events, including intraprocedural and delayed bleeding, were comparable between the groups. CONCLUSION: Both P-EMR and A-EMR demonstrated high R0 resection rates for nonpedunculated polyps measuring 10-25 mm. However, A-EMR achieved these outcomes with a shorter procedure time than P-EMR.

Humans↗

PubMed1992

Cigarette smoking, alcohol use and adenomatous polyps of the sigmoid colon.

The relationship of adenomatous polyps of the sigmoid colon with cigarette smoking and alcohol use was investigated in male self-defense officials in Japan. In the comparison between 116 cases and 930 controls, total ethanol intake was not at all associated with the risk of adenomatous polyps, but cigarette smoking was strongly related to adenomatous polyps. After adjustment for total ethanol intake, body mass index and rank, odds ratios (and 95% confidence interval) for the categories of 0, 1-399, 400-799, and 800 or more cigarette-years were 1.0 (referent), 2.3 (1.1-4.6), 2.9 (1.5-5.4) and 3.2 (1.6-6.5), respectively. Among five alcoholic beverages (sake, shochu, beer, whiskey including brandy, and wine), only whiskey consumption was weakly related to the risk of adenomatous polyps. Because the present findings disagree with an earlier observation on self-defense officials, we examined the association with smoking and alcohol use separately for small (less than 5 mm) and large (greater than or equal to 5 mm) adenomas, combining data from these two studies. Cigarette smoking was more strongly associated with small adenomas while the positive association with certain alcoholic beverages were largely confined to large adenomas. These findings suggest that cigarette smoking and alcohol use may be linked with the development of adenoma at different stages of colon tumorigenesis.

Adenoma↗

PubMed1996

Mucociliary function in patients with nasal polyps.

Patients with nasal polyposis complain of nasal blockage and rhinorrhoea, which may be due to impaired mucociliary clearance. The saccharine clearance time and ciliary beat frequency of samples of ciliated epithelium from patients with nasal polyps was measured. We also studied the effect of fluid from the oedematous stroma of nasal polyps and of histamine and prostaglandin (PG) D2, E2 and F2 alpha on the cilia from normal individuals. Polyp fluid was found to increase ciliary beat frequency. Histamine and PGD2 had no effect, but PGE2 and PGF2 alpha both increased ciliary beat frequency and so may cause the ciliostimulatory effect of polyp fluid. The saccharine clearance time was prolonged in three of nine patients, but ciliary beat frequency was only slightly reduced in one of these. Thus, where mucociliary clearance is reduced, it is likely to be due to abnormalities of mucus rather than impaired ciliary activity.

Cilia↗

PubMed1996

The detection of Mycoplasma pneumoniae in nasal polyps.

The aetiology and microbial flora of nasal polyps is not well understood. No study in the literature has reported an association between the sub-bacterium Mycoplasma pneumoniae and nasal polyps. We have developed an assay method using the Polymerase Chain Reaction (PCR) to amplify a specific region of the M. pneumoniae DNA in extracts of clinical samples using species-specific primers designed to a region of the 16S rRNA. The presence of M. pneumoniae was detected in 13/14 (93%) nasal polyps, in 4/5 (80%) rhinosinusitis mucosal samples but only in 1/7 (14%) of control samples (obstructive turbinates). An epidemic of infections due to M. pneumoniae is expected to occur in 1995. We believe this assay could form the basis of a rapid technique for M. pneumoniae detection. We also propose that the presence of M. pneumoniae may be of importance in the aetiology of nasal polyps.

Blotting, Southern↗

PubMed1993

Prolapse-induced inflammatory polyps of the colorectum and anal transitional zone.

A clinicopathological study of polypoid lesions of the lower gastrointestinal tract from 12 patients was undertaken. Clinically, the majority had signs and symptoms of rectal prolapse despite having a variety of other primary diagnoses (e.g. carcinoma of the bowel or diverticular disease). Three patients were asymptomatic. The polyps were more common in females and were usually solitary. Histologically, fibrin 'caps', fibromuscular hypertrophy and obliteration of the lamina propria, goblet cell hypertrophy and serrated tubules were consistently noted. The fibromuscular tissue often extended into the lamina propria in a radial fashion. This study shows that mucosal prolapse underpins a variety of lesions that are part of a histological spectrum of changes. Inflammatory cloacogenic polyps, inflammatory 'cap' polyps, polypoid prolapsing mucosal folds of diverticular disease and inflammatory myoglandular polyps are all due to mucosal prolapse.

Adult↗

PubMed2003

Overexpression of cyclooxygenase 2 in hamartomatous polyps of Peutz-Jeghers syndrome.

OBJECTIVE: Peutz-Jeghers syndrome (PJS) is an autosomal-dominant hamartomatous polyposis syndrome. Affected individuals are at risk for intestinal and extraintestinal malignancies. Prostaglandins and polyamines are small molecules believed to be important in tumor formation and growth. Cyclooxygenase (COX) and ornithine decarboxylase (ODC) are key enzymes in the prostaglandin and polyamine biosynthetic pathways, respectively. The aim of this study was to measure and compare COX-1 and COX-2 expression in normal and hamartomatous tissue of PJS patients. METHODS: We measured COX-1 and COX-2 protein expression in normal and hamartomatous GI tissues from affected PJS individuals and compared it with that in normal controls. COX-2 RNA in these tissues was also measured and compared by reverse transcription polymerase chain reaction (PCR). In addition, COX-2 expression was detected in tissue slides by immunostaining. ODC activity was measured between normal and hamartomatous tissues of PJS compared with control tissues. RESULTS: COX-1 expression was similar in normal and control GI tissues. In contrast, COX-2 overexpression was noted in hamartomatous polyp tissue from PJS patients compared with normal control and PJS tissue. COX-2 expression by reverse transcription PCR was 10-fold greater in a hamartoma compared with other tissues. COX-2 expression was noted in the epithelial cells of hamartomatous polyps, and also coursing throughout the stromal tissue of the lamina propria, including muscle cells. ODC activity was similar in the tissues studied. CONCLUSIONS: Selective COX-2 overexpression was noted in hamartomatous polyp tissue from PJS individuals. The results of the study provide an avenue for possible effective chemoprevention of polyp formation and growth in PJS.

Blotting, Western↗