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Prevalence of colonic polyps is not increased in patients with acromegaly: analysis of 60 patients from India.

BACKGROUND: There are conflicting data on the prevalence of colorectal adenomas in patients with acromegaly. It has been suggested that the risk of colorectal adenomas may be dependent on the geographic and ethnic origin of the patients. MATERIALS: Sixty consecutive patients with active acromegaly due to somatotropinoma underwent colonoscopy prior to definitive surgery. They included 35 men and 25 women with a mean (+/- SD) age of 37.4 +/- 13.2 years and a lag time between symptomatology and diagnosis of acromegaly of 64.6 +/- 58.0 months. The control group included 160 patients (88 men, 72 women; mean age, 38.2 +/- 14.0 years) with a diagnosis of irritable bowel syndrome who were also subjected to colonoscopy. None of these patients had previous or family history of colonic neoplasm, bleeding or colonic surgery. RESULTS: Colonoscopic examination was complete to the cecum in 52 patients (88%), and to the splenic flexure in the remaining 12%. In the control group, it was complete to the cecum in 144 patients (90%). Four of the acromegalic patients (6.7%) and five in the control group (3.1%; P=0.24) had hyperplastic polyps. No patient in either of the groups had adenomatous polyps or colonic adenocarcinoma. The group of acromegalic patients with and without polyps did not differ significantly in age, duration of disease, growth hormone levels or glycemic status. The number of skin tags, however, was significantly higher (P=0.04) in the polyp group as compared to those without polyps. CONCLUSION: The present study has failed to demonstrate the high prevalence rate of colonic neoplasia in patients with acromegaly as compared to reports from the Western world.

Acromegaly↗

Cardiac glands hyperplastic polyp of the stomach.

Reported herein is a very rare polyp in the gastric cardia of a 49-year-old man. He was referred because of a polyp detected by upper gastrointestinal examination in an affiliated hospital. Endoscopic examination revealed a polyp-like submucosal tumor. Endoscopic ultrasonography revealed minute cystic dilatations and thickening of the submucosal layer. Accordingly, a preliminary diagnosis of cardiac gland hyperplasia was made. The lesion was removed successfully by snare polypectomy. Observed macroscopically, the polyp was 30 mm in diameter and covered with normal gastric mucosa. Examined histologically, the polyp comprised a hyperplastic submucosal cardiac gland.

Cardia↗

Poor correlation between clinical impression, the small colonic polyp and their neoplastic risk.

BACKGROUND AND OBJECTIVES: Significance of the small colonic polyp is unclear and its removal is frequently determined by the proceduralist's clinical impression. Our aims were to determine if clinical discernment is accurate, and the likelihood that lesions < 10 mm are histologically advanced. METHOD: We prospectively collected 1988 lesions from 854 subjects (2215 consecutive colonoscopies). Lesion size, location, patient age, sex and the colonoscopist's clinical impression was recorded. RESULTS: Clinical assessment for neoplasia had a sensitivity of 87.4%, specificity of 65.0%, positive predictive value of 76.0% and negative predictive value of 80.2%, resulting in an accuracy of 73.4%. Factors predictive of correct clinical impression were polyp size, location in the rectum and being pedunculated, but not the patient's age, sex or the endoscopist's experience. Of the 1434 lesions < or = 5 mm in size, 44.5% were neoplastic and 3.5% were histologically advanced. Of the 266 lesions 6-9 mm, 79.3% were neoplastic, 19.9% were histologically advanced, five demonstrated high-grade dysplasia and three were malignant. Only two patients with an adenocarcinoma or high-grade dysplasia in a polyp <10 mm had a lesion > or =10 mm elsewhere in the colon. Of the 288 lesions > or =10 mm in size, 92.7% were neoplastic, 29.5% had a villous component, 6.9% demonstrated high-grade dysplasia and 29.2% were malignant. Factors predictive of neoplasia were patient age, polyp size and sessile nature of the lesion. CONCLUSION: Polyps < 10 mm had a significant risk of neoplasia and advanced histology and, in general, clinical impression correlated poorly with neoplasia. Removal of all lesions proximal to the rectum, regardless of size, should therefore be considered.

Adenocarcinoma↗

Inflammatory esophagogastric polyp and fold in an adolescent.

The case of a 13 year old boy with an inflammatory esophagogastric polyp and ulcerative colitis is described. Endoscopy revealed a typical polyp and gastric fold complex at the esophagogastric junction and a hiatal hernia. Histology of a biopsy specimen confirmed an inflammatory polyp covered by hyperplastic squamous and gastric foveolar epithelium. Continuous 24 hour esophageal manometry suggested gastroesophageal reflux, which may be related to the pathogenesis of the lesion. Follow-up endoscopy showed marked regression of the polyp with medication for reflux esophagitis. This clinical entity is rare in childhood and adolescence, and the manifestations may not be readily recognized. Therefore, endoscopic biopsy is important in children with esophageal polyps. However, polypectomy is unnecessary except when malignancy is suspected or when symptoms persist.

Adolescent↗

Ki-67, Bcl-2 and p53 expression in endometrial polyps and in the normal endometrium during the menstrual cycle.

OBJECTIVE: To determine the presence of proteins related to proliferation (Ki-67) and apoptosis (Bcl-2, p53) in endometrial polyps and normal endometrium during the menstrual cycle. DESIGN: Retrospective study using paraffin embedded tissue. SETTING: Hospital affiliated to the university. POPULATION: Premenopausal patients with endometrial polyps. METHODS: Seventy-eight premenopausal patients in different phases of the menstrual cycle were submitted to polypectomy using the Bettocchi hysteroscope. Immunohistochemistry was used to detect the expression of these proteins in endometrial polyps. One hundred and eighteen normal endometrial biopsies were used as controls. MAIN OUTCOME MEASURES: Detection of Bcl-2 and Ki-67 expression by immunohistochemistry. RESULTS: In endometrial polyps, Ki-67, p53 and Bcl-2 expression was detected with more frequency during the proliferative than during the luteal phase of the cycle. Similar findings were observed in the normal endometrium. CONCLUSION: Endometrial polyps undergo cyclic changes in the expression of their proteins related to proliferation and apoptosis during the menstrual cycle, similar to those of the cycling endometrium.

Adult↗

Seroprevalence of Helicobacter pylori in patients with colorectal polyps and colorectal carcinoma.

OBJECTIVES: The role of Helicobacter pylori in the pathogenesis of colorectal polyps and colorectal carcinoma is unknown. H. pylori infection causes fasting and meal stimulated hypergastrinemia. Gastrin increases colorectal mucosal proliferation and promotes tumor growth. We performed a prospective study to determine the seroprevalence of H. pylori in patients with colorectal polyps and colorectal carcinoma and in controls. METHODS: Blood samples were collected from 189 patients with colorectal carcinoma, 57 patients with colorectal polyps, and 179 controls. H. pylori serology was determined by an ELISA assay. RESULTS: Logistic regression showed no difference in seroprevalence of H. pylori between patients with colorectal cancer and controls (odds ratio, 1.1; 95% confidence interval, 0.7 to 1.8) or between patients with colorectal polyps and controls (odds ratio 1.3; 95% confidence interval, 0.7 to 2.5). Age and sex were not found to be associated with H. pylori infection. Patients in social classes IV and V were 2.3 times more likely to have H. pylori infection than those in social classes I, II, and III (95% confidence interval, 1.3 to 4.2). CONCLUSIONS: This study shows that there is no increase in the seroprevalence of H. pylori in patients with colorectal polyps or colorectal carcinoma compared with controls. These results do not support the hypothesis that there is a relationship between H. pylori infection and the development of colorectal neoplasia.

Adenocarcinoma↗

Feasibility and diagnostic utility of video capsule endoscopy for the detection of small bowel polyps in patients with hereditary polyposis syndromes.

OBJECTIVES: At present, surveillance of premalignant small bowel polyps in hereditary polyposis syndromes has a number of limitations. Capsule endoscopy (CE) is a promising new method to endoscopically assess the entire length of the small bowel. METHODS: We prospectively examined 40 patients with hereditary polyposis syndromes (29 familial adenomatous polyposis (FAP), 11 Peutz-Jeghers syndrome (PJS)). Results were compared with push-enteroscopy (PE) results in FAP and with esophagogastroduodenoscopy, PE, (MR)-enteroclysis, and surgical specimen in PJS patients. RESULTS: A total of 76% of the patients with FAP with duodenal adenomas (n = 21) had additional adenomas in the proximal jejunum that could be detected by CE and PE. Moreover, 24% of these FAP patients had further polyps in the distal jejunum or ileum that could only be detected by CE. In contrast, in FAP patients without duodenal polyps (n = 8), jejunal or ileal polyps occurred rarely (12%). CE detected polyps in 10 of 11 patients with PJS, a rate superior to all other reference procedures employed. Importantly, the findings of CE had immediate impact on further clinical management in all PJS patients. CONCLUSIONS: Our results suggest that CE may be of clinical value in selected patients with FAP, whereas in PJS, CE could be used as first line surveillance procedure.

Adenomatous Polyposis Coli↗

Computer-assisted detection of colonic polyps with CT colonography using neural networks and binary classification trees.

Detection of colonic polyps in CT colonography is problematic due to complexities of polyp shape and the surface of the normal colon. Published results indicate the feasibility of computer-aided detection of polyps but better classifiers are needed to improve specificity. In this paper we compare the classification results of two approaches: neural networks and recursive binary trees. As our starting point we collect surface geometry information from three-dimensional reconstruction of the colon, followed by a filter based on selected variables such as region density, Gaussian and average curvature and sphericity. The filter returns sites that are candidate polyps, based on earlier work using detection thresholds, to which the neural nets or the binary trees are applied. A data set of 39 polyps from 3 to 25 mm in size was used in our investigation. For both neural net and binary trees we use tenfold cross-validation to better estimate the true error rates. The backpropagation neural net with one hidden layer trained with Levenberg-Marquardt algorithm achieved the best results: sensitivity 90% and specificity 95% with 16 false positives per study.

Algorithms↗

Feature-guided analysis for reduction of false positives in CAD of polyps for computed tomographic colonography.

We evaluated the effect of our novel technique of feature-guided analysis of polyps on the reduction of false-positive (FP) findings generated by our computer-aided diagnosis (CAD) scheme for the detection of polyps from computed tomography colonographic data sets. The detection performance obtained by use of feature-guided analysis in the segmentation and feature analysis of polyp candidates was compared with that obtained by use of our previously employed fuzzy clustering technique. We also evaluated the effect of a feature called modified gradient concentration (MGC) on the detection performance. A total of 144 data sets, representing prone and supine views of 72 patients that included 14 patients with 21 colorectal polyps 5-25 mm in diameter, were used in the evaluation. At a 100% by-patient (95% by-polyp) detection sensitivity, the FP rate of our CAD scheme with feature-guided analysis based on round-robin evaluation was 1.3 (1.5) FP detections per patient. This corresponds to a 70-75% reduction in the number of FPs obtained by use of fuzzy clustering at the same sensitivity levels. Application of the MGC feature instead of our previously used gradient concentration feature did not improve the detection result. The results indicate that feature-guided analysis is useful for achieving high sensitivity and a low FP rate in our CAD scheme.

Algorithms↗

Chaotic vibrations of a vocal fold model with a unilateral polyp.

A nonlinear model was proposed to study chaotic vibrations of vocal folds with a unilateral vocal polyp. The model study found that the vocal polyp affected glottal closure and caused aperiodic vocal fold vibrations. Using nonlinear dynamic methods, aperiodic vibrations of the vocal fold model with a polyp were attributed to low-dimensional chaos. Bifurcation diagrams showed that vocal polyp size, stiffness, and damping had important effects on vocal fold vibrations. An increase in polyp size tended to induce subharmonic patterns and chaos. This study provides a theoretical basis to model aperiodic vibrations of vocal folds with a laryngeal mass.

Humans↗

Mucin associated Tn and sialosyl-Tn antigen expression in colorectal polyps.

Sialosyl-Tn antigen and its immediate precursor, Tn antigen, are carbohydrate structures associated with the earliest steps of mucin O-linked glycosylation. Both antigens have been shown previously to be highly sensitive and specific markers of colorectal cancer. One hundred and three colorectal polyps (79 adenomatous; 24 hyperplastic) were examined for expression of Tn antigen using vicia villosa isolectin B4, and for sialosyl-Tn antigen by monoclonal antibody TKH2. Tn antigen was expressed by all of the polyps studied. Sialosyl-Tn, on the other hand was expressed weakly by a few cells in 7 of 24 (29%) hyperplastic polyps. Among the adenomatous polyps, 56% expressed sialosyl-Tn and expression correlated with larger adenoma size, greater villous component, and more severe grades of dysplasia. In individuals with two or more synchronous adenomas, the level of sialosyl-Tn expression within an adenoma was associated with the severity of cytological atypia. All the adenomas that contained a focus of invasive carcinoma expressed sialosyl-Tn. These results indicate that colorectal polyps manifest incomplete glycosylation, exposing antigens in the innermost region of mucin oligosaccharides. In addition, the correlation of sialosyl-Tn antigen expression with the adenoma-carcinoma sequence may make this a useful marker for studying malignant progression in the colon.

Antigens, Neoplasm↗

Patients with adenomatous polyps and carcinomas have increased colonic mucosal prostaglandin E2.

Colorectal carcinoma in humans and animal models is associated with increased synthesis of prostaglandin E2 (PGE2). PGE2 synthesis was measured in normal and neoplastic human colorectal mucosa to investigate its role in the adenoma-carcinoma sequence. Paired mucosal biopsy specimens for PGE2 synthesis and histological examination were obtained during 39 diagnostic colonoscopies. Twelve control patients in whom colonoscopies and histology were normal synthesised similar amounts of PGE2 at all sites. Their results were (mean (SD) pg PGE2/mg tissue) caecum 102.8 (15.9) (n = 6), ascending colon 110.8 (24.3) (n = 10), transverse colon 103.9 (19.5) (n = 11), descending colon 102.9 (23.2) (n = 12), sigmoid colon 96.4 (18.0) (n = 12), and rectum 107.1 (17.6) (n = 12). Nineteen patients had a total of 27 adenomatous polyps (rectum (1), sigmoid (22), descending (1), transverse (1), and ascending colon (1): histology-tubular (16), tubulo-villous (8), and villous adenomous (3)). The polyps (178.0 (55.0), n = 27) synthesised more PGE2 than controls (p < 0.001), but the values in polyp-associated mucosa (mean (SD) 115.4 (21.9), n = 15) were not different to control results. Eight patients had carcinomas (rectal (2), sigmoid (4), and caecal (2)) all of which were adenocarcinomas. The cancers (193.6 (40.2), n = 8) synthesised more PGE2 than control specimens (p < 0.001), but were not different to polyps. Cancer-associated mucosa (140.3 (27.7) n = 8) synthesised more PGE2 than control and polyp-associated mucosa. Colorectal neoplasia is associated with a progressive increase in PGE2 synthesis which may have a role in tumourigenesis and be a pathophysiological explanation for the beneficial effects of NSAIDs in animal models and human disease.

Adenocarcinoma↗

Intestinal polyps in the Nigerian African.

Intestinal polyps appear to be relatively rare in the African including Nigerians, South African Bantus, and Ugandans. Only 40 histologically confirmed cases were encountered over a period of ten years. Analysis of these cases reveals a preponderance (60%) of the non-neoplastic juvenile type of polyp. Neoplastic polyps were not encountered in any female patient. The mean ages of the patients are much lower than what has been observed in Caucasians inhabiting developed and industrialized countries. It is felt that there is probably a common or related aetiological agent for neoplastic intestinal polyps and carcinoma because the frequency of intestinal carcinoma appears to be relatively low in areas with a low frequency of neoplastic polyps.

Adolescent↗

Comparative study of the effects of different glucocorticosteroids on eosinophil survival primed by cultured epithelial cell supernatants obtained from nasal mucosa and nasal polyps.

BACKGROUND: Supernatants from epithelial cell cultures enhance eosinophil survival in vitro, this effect being abrogated by previous incubation of eosinophils with glucocorticosteroids. This property has resulted in the development of an in vitro test to compare the potency of these drugs. A comparative study was performed with dexamethasone, methylprednisolone, deflazacort, and budesonide. METHODS: Human epithelial cell conditioned media (HECM) was generated from cultured epithelial cells obtained from healthy nasal mucosa and polyps. Eosinophils isolated from the peripheral blood were incubated with different corticosteroids for one hour before the addition of HECM. The inhibitory potency of the four steroids on the eosinophil survival index was compared using the concentration of steroid causing 50% inhibition (IC50). RESULTS: Eosinophil survival was increased by HECM from both healthy nasal mucosa and polyps. All four steroids blocked HECM-induced eosinophil survival in a dose-dependent manner. On healthy nasal mucosa methylprednisolone was the least potent (IC50 = 536 nM), deflazacort (IC50 = 264 nM) was twice as potent as methylprednisolone, while budesonide and dexamethasone were approximately nine times as potent (both IC50 = 58 nM). When potency was evaluated on the promoting effects of the HECM obtained from nasal polyps, the inhibitory potencies were lower and consequently the IC50 values were higher when compared with HECM generated from healthy nasal mucosa: methylprednisolone (IC50 = 546 nM), deflazacort (IC50 = 390 nM), dexamethasone (IC50 = 76 nM), and budesonide (IC50 = 78 nM). CONCLUSIONS: The potencies of glucocorticosteroids can be compared by evaluating their effects on the survival of eosinophils previously primed by supernatants obtained from epithelial cell culture. The different effects of steroids on eosinophils primed by HECM obtained from healthy nasal mucosa compared with HECM obtained from nasal polyps suggest that polyps might represent more active tissue which is relatively resistant to treatment with corticosteroids.

Administration, Topical↗

Glucocorticoids decrease c-fos expression in human nasal polyps in vivo.

BACKGROUND: Activated c-fos binds to jun proteins to form the activation protein 1 (AP-1) transcription factor that regulates cytokine and other proinflammatory genes. c-Fos may play a key role in nasal polyp formation. Glucocorticoids may exert their anti-inflammatory effects through an interaction of glucocorticoid receptors with AP-1 that leads to mutual inactivation of both factors, and a "default" termination of AP-1 mediated gene activation. This may explain the beneficial effects of glucocorticoids in the treatment of nasal polyps. METHODS: To test this hypothesis in humans in vivo the immunohistochemical expression of c-fos-immunoreactive material (c-fos-irm) was assessed in nasal polyps from eight steroid naive subjects, polyps from eight subjects treated with topical beclomethasone dipropionate (BDP), and normal inferior turbinate nasal mucosa (n = 6). RESULTS: mRNA for c-fos was detected in all nasal polyps and normal mucosa. In contrast, c-fos-irm was present in all steroid naive subjects but in only two of the eight subjects treated with BDP (p = 0.007, two-tailed Fisher's exact test). c-Fos-irm was expressed solely in epithelial cells and glandular structures; it was expressed in normal epithelium and glands, but the staining intensity was low. CONCLUSION: Glucocorticoids appear to modulate expression of c-fos-irm and possibly AP-1 in human airway epithelial cells in vivo.

Adult↗

Gastric polyps on routine double-contrast examination of the stomach.

Gastric polyps were found in 38 patients in a series of 2,420 consecutive double-contrast studies of the upper gastrointestinal tract. The resulting incidence of 1.6% is four times the highest figure previously reported. Single polyps were usually located in the antrum, multiple polyps in the body of fundus. Two-thirds were less than or equal to 10 mm in diameter; only one was larger than 20 mm. Endoscopy was performed in 17 cases and showed either normal or inflamed gastric mucosa with no evidence of neoplasia. It is likely that most gastric polyps are inflammatory or hyperplastic, while the biopsies showing normal mucosa may represent small submucosal tumors such as leiomyomas. This study demonstrates the high frequency and innocuous nature of small gastric polyps.

Adult↗

Bowler-hat sign: a simple principle for differentiating polyps from diverticula.

The bowler-hat sign has been described both with colonic polyps and with diverticula. The authors describe a simple principle for evaluating a bowler-hat sign in order to determine whether it is caused by a polyp or a diverticulum. If the bowler hat points toward the center of the long axis of the bowel, it represents an intraluminal structure (ie, a polyp). If, however, it points away from the center of the long axis of the bowel, it represents an extraluminal structure (ie, a diverticulum). Only if the bowler hat is located in the midline or is directly parallel to the long axis of the bowel is it impossible to classify the abnormality as a polyp or a diverticulum. The value of this principle was confirmed with both a radiographic model and a blinded review of radiographs from 37 cases demonstrating the bowler-hat sign. When a bowler hat is present on a double-contrast barium enema examination, use of this principle provides a simple and objective means of differentiating a polyp from a diverticulum.

Barium Sulfate↗

Sphenochoanal polyps: evaluation with CT and MR imaging.

A sphenochoanal polyp is a solitary mass of low attenuation on computed tomographic (CT) scans that arises from the sphenoid sinus and extends through the sphenoid ostium, across the sphenoethmoid recess, and into the choana (the boundary between the nasal cavity and nasopharynx). More often, however, a choanal polyp is an antrochoanal polyp, which arises from the maxillary antrum, protrudes through the middle meatus, extends into the nasal cavity, and continues back to the choana. Contiguous axial or coronal magnetic resonance and CT images help clearly differentiate the rare sphenochoanal polyp from the more common antrochoanal polyp. The sinus of origin is important to identify, as the surgical approach depends on the target sinus.

Adult↗