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At least 613 records · Page 34Linked to original sources
PubMed1999

Laparoscopic surgery in the treatment of colonic polyps.

BACKGROUND: Benign colonic polyps that are impossible to remove with the aid of the flexible colonoscope because of their size or location must be removed surgically. METHODS: Twenty patients with colonic adenomatous polyps that could not be resected by colonoscopy because of size or difficult location (n = 18) or polyps in combination with diverticulitis (n = 2) underwent polyp removal through a small 'assisted' incision in the abdominal wall using a standard 'dissection-facilitated' laparoscopic approach to the affected colonic segment. RESULTS: In six patients the polyp was removed through a colotomy, in three through a limited resection (two ileocaecal and one limited sigmoid resection) and in 11 through a standard colectomy (four right hemicolectomy, one left hemicolectomy, four sigmoid and two anterior resections) because of suspicion of cancer. In only one patient could the polyp not be found during laparoscopy, resulting in a second conventional surgical intervention. In four patients carcinoma was diagnosed in the specimen. CONCLUSION: Precise preoperative localization of the polyp and the use of dissection-facilitated laparoscopic colonic surgery make laparoscopic removal of benign colonic polyps an alternative to an open procedure.

Aged↗
PubMed1999

Metaplastic polyp of the colon develops in response to inflammation.

BACKGROUND: The metaplastic polyp of the colon is a non-neoplastic lesion that is generally identified as white, flat and having a smooth surface. In general, this polyp is small, is less than 5 mm in diameter but is occasionally larger than 5 mm in diameter, and forms a swelling. The aims of the present study were to clarify the factors that determine the morphology of protruding metaplastic polyps. More specifically, we investigated whether the metaplastic polyp forms as a result of an abnormality in cell proliferation or inflammation of the region. METHODS: We examined 15 endoscopically resected metaplastic polyps of the colon having a longitudinal diameter of more than 5 mm. To study aspects of cell proliferation, we used proliferating-cell nuclear antigen (PCNA) staining. For examination of histological changes caused by inflammation, we used alpha-smooth muscle actin (alphaSMA) staining, in which myofibroblasts are specifically stained. RESULTS: Metaplastic polyps showed significantly higher expression of PCNA, not only in the deep layer, but also in the intermediate and superficial layers, compared with the normal mucosa of the colon. In the protruding metaplastic polyps, anti-alphaSMA staining revealed bundle-like myofibroblasts in the interstitium. CONCLUSIONS: The factors responsible for the formation of non-neoplastic metaplastic polyps larger than 5 mm with a protruding morphology are: an increased number of epithelial cells due to the movement of these cells toward the ductal epithelium in the proliferating zone; and expansion of interstitial tissues due to infiltration of myofibroblasts and other inflammatory cells in response to inflammation.

Actins↗
PubMed2000

The bright edge of the endometrial polyp.

OBJECTIVE: To evaluate the accuracy of sonographic detection of endometrial polyps using a new ultrasound marker denoted 'the bright edge of the polyp'. METHODS: The ultrasound scans of the uterus were examined for the presence of the bright edge in two groups of women. The first, a retrospective group, included 40 women in whom both a histological diagnosis of endometrial polyps and sonographic scans were available for evaluation. The second, a prospective group, included 80 women scheduled for operative hysteroscopy because of endometrial irregularities detected by sonography. In this group the hysteroscopical and histological results of the removed endometrial tissue were correlated with the sonographic diagnosis. RESULTS: In the retrospective group, the bright edge marker, indicative of the presence of a polyp, was detected in 30 out of 40 scans available for evaluation. In the prospective group this marker was detected in 60 women out of 80. Endometrial polyps were confirmed in 56 of these 60 women. In three cases a submucosal myoma was found and in one case the histology showed simple cystic hyperplasia. Two polyps were found in 20 cases where the bright edge had not been detected. This marker has a sensitivity of 96%, specificity of 82%, positive predictive value of 93%, and negative predictive value of 90% in this group at high risk for endometrial abnormalities. CONCLUSION: The bright edge of the polyp is an accurate sonographic marker for the detection of endometrial polyps in women with endometrial irregularities demonstrated on ultrasound.

Case-Control Studies↗
PubMed2004

Comparison of capsule endoscopy and magnetic resonance imaging for the detection of polyps of the small intestine in patients with familial adenomatous polyposis or with Peutz-Jeghers' syndrome.

BACKGROUND AND STUDY AIMS: We have conducted a study to compare the diagnostic yields of magnetic resonance imaging (MRI) and capsule endoscopy for the detection of small-bowel polyps in patients with inherited polyposis syndromes. PATIENTS AND METHODS: MRI was performed in 20 patients, with either Peutz-Jeghers' syndrome (PJS; n = 4) or familial adenomatous polyposis (FAP; n = 16), and capsule endoscopy was done the next day. The number, size, and location of polyps were analyzed. RESULTS: Overall, 448 polyps ranging from about 1 mm to 30 mm in size were detected in eight patients by capsule endoscopy, whereas with MRI only 24 polyps all bigger than 5 mm could be seen in the four PJS patients. CONCLUSIONS: Polyps bigger than 15 mm were detected similarly with capsule endoscopy and MRI, whereas smaller polyps were seen much more often with capsule endoscopy. Polyps smaller than 5 mm were exclusively seen with capsule endoscopy. However, location of the detected polyps and determination of their exact sizes was more accurate by MRI.

Adenomatous Polyposis Coli↗
PubMed1986

[Gastric polyps and their relations with gastric carcinoma].

In 31 of 33 patients with polyps of the stomach who underwent gastroscopy and x-ray examination the polyps could be diagnosed roentgenologically. 11 patients had multiple polyps, which were in 8 cases hyperplastic polyps, in 3 "other polyps", whereas in 20 patients with solitary polyps 11 cases showed hyperplastic, in 5 cases adenomatous and in 4 cases "other" polyps. After x-ray analysis it can be stated that in our cases the premalignant adenomatous polyp always occurred solitary.

Adult↗
PubMed1991

[The localization of colorectal polyps and carcinomas in relation to their size and the histological findings].

Location, size and histological appearance of colorectal neoplasms were examined retrospectively. A total of 1,357 polyps (including small ones, diameter below 0.5 cm) were found in 1,022 of 3,057 coloscopies. The coloscopies were indicated by findings on preceding radiological or endoscopic examinations (48%), occult blood in stool (18%), during follow-up after polypectomy (21%), and after colorectal carcinoma (13%). A single polyp was found in 718 cases (70%), two to four in 221 (26%), more than five in 33 (4%), 1,106 polyps (61%) were found on high coloscopy; 380 of these (38%) were located proximal to the left flexure. Among the 1,230 polyps examined histologically 907 (74%) were adenomas (494 tubular [54%], 379 tubulovillous [42%], 34 villous [4%]). 251 (28%) of the adenomatous polyps and 49 (32%) of the 151 carcinomas were located proximal to the left flexure. The incidence of moderately severe to severe dysplasias increased with increasing diameter of the polyps: 55% of those smaller than 0.5 cm were adenomas. 70% of polyps with a diameter over 1.0 cm were tubulovillous or villous adenomas. The findings confirm that there is a high incidence of polyps proximal to the left flexure. A complete coloscopy should therefore be done as a matter of course.

Age Factors↗
PubMed1985

[Multiple colorectal polyps and risk of cancer].

The malignancy rate ("severe cellular atypia' and "invasive carcinoma' in adenomas and associated carcinoma) was determined in a retrospective study on 95 patients, aged 28 to 97 years (median age 65 years), with colonoscopy findings showing multiple (more than 8) colorectal polyps. It amounted to 22% to 100% in patients with 8 and up to more than 50 polyps in the colorectum. The malignancy rate was "only' 3.7% to 11.8% based on the number of polyps in the individual patients and thus was about the same as in patients with an isolated or few polyps. Thus, malignancy rate increases with number of polyps (by far the majority adenomas). Endoscopy showed the presence of gastric polyps in eleven of the 95 patients (11.6%) with multiple colorectal polyps. With the exception of one "borderline lesion' they were benign, showing no definite tendency towards malignancy. After endoscopic ectomy of the multiple polyps surgical treatment (procto-mucosectomy, segment resection, hemicolectomy or colectomy) was necessary in 37 patients (39%).

Adenoma↗
PubMed2000

Relation of epidermal growth factor receptor expression to goblet cell hyperplasia in nasal polyps.

BACKGROUND: Because the epidermal growth factor receptor (EGFR) system regulates mucin production in airway epithelium, we hypothesized a role for this system in mucus hypersecretion that occurs in nasal polyposis. OBJECTIVE: We examined the relationship between goblet cell hyperplasia, EGFR expression, and inflammatory mediators produced by eosinophils and neutrophils in nasal polyp tissues. METHODS: Nasal polyp tissue samples from 8 patients and nasal turbinate biopsy specimens from 6 normal control subjects were examined for alcian blue/PAS staining, mucin MUC5AC (MUC5AC), and EGFR immunoreactivity and EGFR gene expression (in situ hybridization). We also examined the role of eosinophils and neutrophils in goblet cell hyperplasia. RESULTS: In control nasal mucosa alcian blue/periodic acid-Schiff- and MUC5AC-stained areas were 18.40% +/- 1.31% and 21.89% +/- 1.43%, respectively. In polyps the alcian blue/periodic acid-Schiff- and MUC5AC-stained areas were 51.30% +/- 5.85% and 52.07% +/- 6.58%, which was significantly larger than that found in control subjects (each comparison, P <.01). Four of 6 control specimens expressed EGFR messenger RNA and protein weakly in the epithelium. In polyps 4 of 8 specimens expressed EGFR gene and EGFR protein strongly; the EGFR-stained area was greater in hyperplastic than in pseudostratified epithelium. TNF-alpha immunoreactivity, expressed in eosinophils, was increased in EGFR-positive polyps compared with EGFR-negative polyps, suggesting a role for TNF-alpha in EGFR expression. Neutrophils were increased in the epithelium of EGFR-positive compared with EGFR-negative polyps, suggesting a role for these cells in mucin expression and in goblet cell degranulation. CONCLUSION: These data suggest a role for EGFR cascade in the regulation of goblet cell mucins in nasal polyps. Proof of concept will require clinical studies using selective EGFR inhibitors.

Cell Movement↗
PubMed2007

Pregnancy outcome of uterine arterial embolization followed by selective hysteroscopic removal of a placental polyp.

OBJECTIVE: To evaluate the pregnancy outcome of uterine arterial embolization followed by selective hysteroscopic removal of a placental polyp. METHODS: Thirteen patients of placental polyp with abundant blood flow, which was diagnosed by ultrasound with color Doppler imaging, were studied. They underwent uterine arterial embolization followed by selective hysteroscopic removal of the polyp. Uterine arterial embolization was carried out using an absorbable gelatin sponge. Selective removal via hysteroscopy was performed on the following day, using the cutting loop with or without electrical stimulation. The polyp was gradually resected to the level of the surrounding endometrium. RESULTS: Complete removal of the placental polyp was achieved in all patients. The presence of placental polyp was confirmed by pathologic examination. The operative time ranged from 20 to 53 min. In all cases, no complications were noted and the bleeding was minimal during and immediately after the procedure. Postoperative ultrasound demonstrated a uterine cavity free of residual mass in each case. The seven patients with complete gestation gave birth to health babies. No recurrence of placental polyp was observed. CONCLUSIONS: Selective removal directed via hysteroscopy after reduction of blood supply by uterine arterial embolization provides a safe and effective method to minimize bleeding, and can preserve future fertility and successful uneventful pregnancies in the treatment of placental polyp with abundant blood flow.

Adult↗
PubMed2002

High levels of nitric oxide synthase activity are associated with nasal polyp tissue from aspirin-sensitive asthmatics.

The pathogenesis of aspirin intolerance remains unclear. Inducible nitric oxide synthase (iNOS) expression is upregulated in nasal polyp epithelium, implying a role for nitric oxide (NO) in its formation. We decided to compare iNOS activity in polyp tissue from patients with and without aspirin intolerance. Nasal polyp tissue was collected from 15 patients undergoing routine nasal polypectomy. These patients were classified into three groups: Group A comprised patients with nasal polyps without asthma; Group B contained patients with nasal polyps and asthma; and Group C comprised patients with nasal polyps, asthma and aspirin sensitivity. All subjects in Group C had a history of aspirin-induced reaction and a confirmatory intranasal challenge with lysine-aspirin. NOS activity was measured by the ability of tissue homogenates to convert 3,4-L-arginine to L-citrulline in an L-N(G)-nitro-L-arginine-inhibitable fashion. The iNOS activity (picomoles) in polyp tissue from the 3 groups was: A, 248.72+/-220.79; B, 23.71+/-41.06; and C, 549.71+/-132.11. Thus, nasal polyps from patients with Samter's triad had a significantly higher iNOS activity (p = 0.004; one-way ANOVA). This finding does not correlate simply with disease severity or with the occurrence of asthma and could indicate another important facet of aspirin-induced airways disease.

Adult↗
PubMed2004

Increased expression of matrix metalloproteinase-2 in nasal polyps.

OBJECTIVE: The formation and growth of nasal polyps requires remodeling of the extracellular matrix. Matrix metalloproteinases (MMPs) are a family of endopeptidases that can collectively degrade almost all extracellular matrix components. The aim of this study was to investigate the role of MMPs in nasal polyps. MATERIAL AND METHODS: The expression of MMP-2 and -9 was investigated in the nasal polyps of 20 patients undergoing endonasal sinus surgery and compared with that in control nasal mucosal samples obtained from 20 non-allergic hypertrophic rhinitis patients. Tissue samples were either homogenized for reverse transcriptase polymerase chain reaction analysis or frozen for immunohistochemistry. RESULTS: MMP-2 mRNA expression was observed only in the nasal polyp samples and not in the control tissues. MMP-9 mRNA was not expressed in either type of tissue. Similarly, MMP-2 expression was observed in the nasal polyps of chronic sinusitis patients but not in the inferior turbinate mucosa of the control subjects. MMP-2 positivity was present in basal cells in the surface epithelium and in infiltrating cells in subepithelial tissues. MMP-9-positive cells were not observed in either nasal polyps or inferior turbinates. These results suggest that MMP-2 expression is characteristic of nasal polyps. CONCLUSION: MMP-2 may play a role in the remodeling of nasal polyps.

Actins↗
PubMed2005

Expression and distribution of thioredoxin and thioredoxin reductase in human nasal mucosa and nasal polyp.

CONCLUSIONS: The results of this study indicate that thioredoxin (Trx) and thioredoxin reductase (TrxR) may play a role in the defense of normal human nasal mucosa against external noxious stimuli. Based on the fact that normal nasal mucosa is continuously exposed to inhaled toxicants and contains a considerable number of inflammatory cells, Trx and TrxR may be upregulated even in normal nasal mucosa and perhaps the difference in their expression levels between normal nasal mucosa and nasal polyp, if it exists at all, is small and therefore difficult to detect. Further studies will be needed to clarify the roles of Trx and TrxR in the pathogenesis of nasal polyp. OBJECTIVES: The cellular antioxidant defense system includes thiol-containing proteins such as Trx and TrxR, which have recently attracted much attention due to their strong antioxidant radical quenching capabilities and other important biological functions related to the regulation of the cellular redox state. This study was undertaken to investigate the expression and distribution of Trx and TrxR in normal human nasal mucosa and nasal polyp, and to improve understanding of the significance of the Trx system in these conditions. MATERIAL AND METHODS: The expression and distribution of Trx and TrxR in normal human inferior turbinate mucosa and nasal polyp were investigated using reverse transcriptase polymerase chain reaction (RT-PCR), semiquantitative RT-PCR, Western blotting and immunohistochemistry. RESULTS: mRNAs and protein for both Trx and TrxR were detected in normal human inferior turbinate mucosa and nasal polyp. Semiquantitative RT-PCR and Western blotting revealed that there was no significant difference in the expression levels of Trx and TrxR between inferior turbinate mucosa and nasal polyp. Immunoreactivity for both Trx and TrxR was seen in nasal epithelial cells, glands and vascular endothelium of inferior turbinate mucosa and nasal polyp. Trx and TrxR immunoreactivity was also found in inflammatory infiltrating cells in inferior turbinate mucosa and nasal polyp.

Adult↗
PubMed2006

Expression of ecalectin, a novel eosinophil chemoattractant, in nasal polyps.

CONCLUSION: Ecalectin, which is produced in the mucosa of nasal polyps, seems to play an important role in the accumulation and activation of eosinophils in nasal polyps, regardless of the presence or absence of atopic predisposition. OBJECTIVE: Ecalectin is a recently discovered eosinophil chemoattractant which elongs to the galectin family. We investigated the expression of ecalectin in nasal polyp tissues associated with various nasal and paranasal diseases in order to clarify the pathogenesis of eosinophilia in nasal polyposis. MATERIAL AND METHODS: Nasal polyps were taken from 56 patients diagnosed as having chronic sinusitis with nasal polyposis. The surgically resected polyps and nasal turbinates were immunohistochemically stained using antibodies against EG2, human mast cell tryptase, CD3 and ecalectin. RESULTS: The number of EG2- and ecalectin-positive cells was significantly higher in nasal polyps than control turbinates. Ecalectin-positive cells were observed in the subepithelial layer, where many EG2-positive cells were present. The number of ecalectin-positive cells correlated significantly with the number of EG2-positive cells in nasal polyps. Many ecalectin mRNA-positive cells were also observed in nasal polyps with an accumulation of EG2-positive cells.

Adolescent↗
PubMed1999

Eotaxin synthesis by nasal polyp fibroblasts.

Nasal polyps is a chronic inflammatory disease of the upper airway characterized by structural abnormalities including stromal fibrosis. Fibroblasts are a rich source of cytokines and inflammatory mediators and are thought to play an important role in the development of fibrosis. In addition, there is considerable evidence for the participation of eosinophils in the pathophysiology of nasal polyps. Although increased numbers of eosinophils are present in nasal polyps, the mechanisms responsible for their selective accumulation are not completely clear. Eotaxin is a chemokine that promotes the selective recruitment of eosinophils. Thus, it may be an important molecule for the recruitment of eosinophils in nasal polyps. The purpose of this study was to investigate whether nasal polyp fibroblasts synthesize eotaxin after stimulation with lipopolysaccharide, IL-1beta or TNF-alpha. Using primary nasal polyp tissue-derived fibroblast lines, we demonstrated that LPS, IL-1beta and TNF-alpha induced the gene expression and protein production of eotaxin in nasal polyp fibroblasts. This responsiveness to LPS, IL-1beta and TNF-alpha was time- and dose-dependent. These findings support the hypothesis that fibroblasts could play an important role in the recruitment of eosinophils in nasal polyps through the production of eotaxin.

Cells, Cultured↗
PubMed2006

Flat gastric polyps: results of forceps biopsy, endoscopic mucosal resection, and long-term follow-up.

OBJECTIVE: Histological examination of specimens obtained by forceps biopsy sampling of gastric polyps is of limited accuracy, and their management on this basis is therefore controversial. The aim of this prospective study was to assess the value of forceps biopsy sampling in establishing the correct diagnosis revealed by endoscopic mucosal resection (EMR). The complication rate of EMR was also determined. MATERIAL AND METHODS: Subjects with gastric polyps of epithelial origin, of at least 0.5 cm in diameter, and not associated with polyposis syndromes, were included in the study. Between 1994 and 2004, 56 gastric polyps in 44 patients (30 F, 14 M, mean age 67 years) met the inclusion criteria. Indigo carmine dye staining and electronic magnification were used in all cases. Following forceps biopsy sampling, 56 EMRs were performed. The histological results of the forceps biopsy and the resected specimens were analyzed. RESULTS: The initial forceps biopsies identified in situ carcinoma in 3 cases, adenoma with no dysplasia in 19, adenoma with low-grade dysplasia in 2, adenoma with moderate-grade dysplasia in 6, adenoma with high-grade dysplasia in 7, and hyperplastic lesions in 19 cases. The histological examination of the resected polyps revealed in situ carcinoma in 5 cases, carcinoid in 1, gastrointestinal stromal tumor in 1, adenoma with no dysplasia in 14, adenoma with low-grade dysplasia in 3, adenoma with moderate-grade dysplasia in 9, adenoma with high-grade dysplasia in 1, hyperplastic lesions in 21, and no diagnosis in 1 case. Complete agreement between the histological results on the forceps biopsy sample and on the ectomized polyp was seen in only 31 (55.3%) polyps. There were important disagreements in 12 cases. In 14 neoplastic and 1 hyperplastic polyps, the degree of dysplasia seen on histological examination of the forceps biopsy specimens differed from that observed for the resected specimens. Post-mucosectomy bleeding was observed in 3 patients, all of whom were successfully treated endoscopically. CONCLUSIONS: Forceps biopsy is not sufficiently reliable for the identification of gastric polyps. These lesions should be fully resected by EMR for a final diagnosis and (depending on the lesion size and type) possibly definitive treatment.

Adult↗
PubMed1980

Immunohistologic study of blood group substances in polyps of the distal colon. Expression of a fetal antigen.

Forty-four polyps and 14 adenocarcinomas of the left colon from 28 patients were studied for the presence of blood group substances of the A, B system, using the method of specific erythrocytic adherence. Forty-one percent of all polyps and 57% of all cancers were found to have reactivity for blood group substances. Fifty-four percent of villous adenomas (seven of 13), 39% of tubular adenomas (five of 13), 14% of mixed tubulovillous adenomas (one of seven), and no hyperplastic polyps (zero of four) showed reactivity for blood group substances. Lesional blood group substance reactivity, when present, was the same as that for the patient's own blood group type, with the exception of two patients of B blood group type, whose lesions had A-blood group substance reactivity. Cytologic atypia showed no correlation with the presence of blood group substances. Polyps with blood group substance reactivity were seen more frequently in patients with cancer. Twelve patients had both a cancer and a polyp studied, with both polyp and cancer showing similar blood group substance reactivity for nine of these patients. A, B, H-blood group substances in the left colon are normally absent in the adult and present only in the fetus. The reappearance of these fetal antigens in both polyps and cancers adds immunologic evidence to the theory that colonic adenocarcinoma evolves through a polyp-cancer sequence.

ABO Blood-Group System↗
PubMed1987

Multiparameter flow cytometric analysis of colon polyps.

Sixty-eight colonic polyps of various histologic types were studied using retrospective flow cytometric (FCM) DNA analysis to determine the prevalence of aneuploid cell populations and whether they were associated with any particular histologic features. Overall, 13 of 68 polyps (19%) contained DNA-aneuploid cells, including 3 of 9 villous and 4 of 10 villoglandular polyps with histologic features of carcinoma in situ (CIS), 4 of 11 villous and 1 of 18 villoglandular polyps without CIS, and 1 of 12 adenomatous polyps. Eight hyperplastic polyps were diploid. These results show retrospective FCM analysis can detect DNA aneuploidy in polyps; DNA aneuploidy may occur before histologic evidence of invasive carcinoma; and this change is more frequent in types of polyps thought to have increased malignant potential (i.e., those with villous morphology and/or CIS).

Adenoma↗
PubMed1995

Effects of docosahexaenoic acid (DHA) on intestinal polyp development in Apc delta 716 knockout mice.

Epidemiological studies and animal experiments show an association of dietary intake of fish oils and low incidence of several types of cancers. The active ingredients of fish oils appear to be polyunsaturated fatty acids of omega-3 type such as eicosapentaenoic acid and docosahexaenoic acid (DHA). We have investigated chemopreventive effects of DHA on mouse intestinal polyposis using adenomatous polyposis coli (Apc) gene knockout mice. Damage to the human APC gene is responsible for not only familial adenomatous polyposis but also many sporadic cancers of the entire digestive tract. Using homologous recombination in embryonic stem cells, we recently constructed gene knockout mice containing a truncation mutation in the Apc gene at codon 716 (Apc delta 716). The heterozygous mice developed numerous intestinal polyps, and all microadenomas dissected from the earliest polyps had already lost the wild-type allele, indicating the loss of heterozygosity [Oshima et al. (1995), Proc. Natl Acad. Sci. USA, 92, 4482-4486]. We fed Apc delta 716 heterozygotes with AIN-76A purified diet containing 3% DHA for 7 weeks, and scored the number and size of intestinal polyps. Average DHA intakes per day were 4.1 and 4.3 g/kg body wt for males and females, respectively. DHA-fed females had only 31% of polyps compared with the control females that developed about 220 polyps, whereas DHA-fed females showed no significant decrease in the polyp number. As for the polyp size, the proportion of larger polyps decreased more significantly in females than in males. This is the first demonstration that DHA inhibits intestinal polyposis induced by an Apc mutation at both its formation and growth.

Animals↗