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At least 595 records · Page 33Linked to original sources
PubMed2002

Adenocarcinoma in solitary large hyperplastic polyp diagnosed by magnifying colonoscope: report of a case.

We report a case of carcinoma in a hyperplastic polyp in a 78-year-old female that was diagnosed before resection using a magnifying colonoscope. The patient presented with fecal occult blood and underwent total colonoscopy, which revealed a 12-mm sessile polyp in the cecum. When seen in magnified view, an irregularly shaped pit was evident at the center of the polyp that was distinct from the asteroid-type pits observed over most of the lesion. We diagnosed this lesion as a hyperplastic polyp with a carcinoma component. The patient underwent endoscopic mucosal resection, and histologic section revealed a well-differentiated intramucosal adenocarcinoma in the hyperplastic polyp. Hyperplastic polyps of the colon are regarded as benign, nonneoplastic lesions. Few have reported carcinomas in or with hyperplastic polyps, and most of those were diagnosed after resection and histologic investigation. The literature suggests a precise observation and consideration of resection for large solitary hyperplastic polyps in the right side of the colon, because the risk of malignancy is high. Magnifying colonoscopy is helpful for observing the surface in detail and for correctly diagnosing and managing the lesion.

Adenocarcinoma↗
PubMed2006

Can endoscopic ultrasonography differentiate nonneoplastic from neoplastic gallbladder polyps?

The present study aimed to clarify the endoscopic ultrasonography (EUS) features of nonneoplastic (cholesterol polyps and adenomyomatosis) and neoplastic (adenoma and adenocarcinoma) gallbladder polyps and to evaluate the effectiveness and limitation of EUS in the differential diagnosis of these lesions. We retrospectively compared EUS images with histologic findings in 29 surgical cases with gallbladder polyps with a diameter of 10 to 20 mm. Those cases were indicated for surgery based on the findings of a sessile appearance, a solitary lesion, low echogenicity, and/or a lobulated surface. Six of 10 cholesterol polyps were atypically seen as partially or completely hypoechoic due to predominant proliferation of glandular epithelia. Nine of 10 cholesterol polyps demonstrated an aggregation of hyperechoic spots, which represented multiple granules of cholesterosis. All adenomyomatoses (n = 10) showed multiple microcysts, which corresponded to proliferated Rokitansky-Aschoff sinuses. However, three of nine neoplastic lesions (three adenomas and six adenocarcinomas) showed one of these signs due to concomitant cholesterosis (n = 2) or proliferated Rokitansky-Aschoff sinuses (n = 1). In conclusion, 69% (20/29) of gallbladder polyps larger than 10 mm that were preoperatively suspected of malignancy were nonneoplastic. An aggregation of hyperechoic spots and multiple microcysts are considered to be important predictive factors for cholesterol polyps and adenomyomatosis, respectively. However, we should caution that these findings can also occur in neoplastic polyps when they contain a concomitant nonneoplastic component (cholesterosis or proliferated Rokitansky-Aschoff sinuses).

Adenocarcinoma↗
PubMed2006

Hyperplastic polyps of the gastric antrum in patients with gastrointestinal blood loss.

The significance of hyperplastic polyps of the gastric antrum in anemic patients with suspected gastrointestinal bleeding has not been determined. The aim of this study is to evaluate the prevalence and prognosis of such polyps in this patient group. Clinical records of patients referred to our endoscopy lab from November 1999 to February 2003 for the evaluation of iron deficiency anemia or suspected gastrointestinal bleeding were reviewed. There were 987 patients. Fourteen patients (1.4%) had hyperplastic polyps in the gastric antrum. Five of the patients reported melena, but the rest were asymptomatic. Multiple antral polyps were present in seven cases. The largest polyp measured 5.0 cm. Helicobacter pylori infection was present in one patient. All patients were anemic and nine had documented iron deficiency. No follow-up information was available in four patients. Hyperplastic polyps of the gastric antrum are a rare but significant cause of gastrointestinal blood loss in older patients. Removal of the polyps using endoscopic or surgical methods may be required for resolution of the blood loss along with iron supplementation. Gastroenterologists should be aware that hyperplastic polyps of the gastric antrum might result in gastrointestinal blood loss and iron deficiency anemia.

Aged↗
PubMed1995

Effect of sulindac on sporadic colonic polyps.

BACKGROUND/AIMS: We sought to determine in a double-blinded, placebo-controlled study if the nonsteroidal anti-inflammatory drug sulindac causes regression of sporadic colonic polyps. The impetus for this study is the profound regressive effect of sulindac on polyps in familial adenomatous polyposis. METHODS: Asymptomatic patients undergoing routine screening flexible sigmoidoscopy were enrolled if they had polyps of < or = 1 cm in size. Of 162 patients screened, 22 patients were randomly enrolled to take 150 mg of sulindac twice daily, and 22 patients took a placebo. Treatment duration was 4 months and was followed by colonoscopy with removal of all polyps. RESULTS: Four patients were dropped from the study (sulindac group) due to urosepsis (1 patient), heartburn (2 patients), and anemia (1 patient). Compliance (determined by monthly pill counting), mean age, and the effect of sulindac vs. placebo on polyp regression or size were not statistically different in the two treatment groups. Analysis of our data indicated that there is only a 0.8% chance that the probability of polyp regression with sulindac is as large as 50%. CONCLUSIONS: Four months of treatment with sulindac does not result in a clinically significant regression of sporadic colonic polyps, although a small effect may not have been detected by the size of our study. Our data suggest that the biological response of sporadic and familial polyposis polyps to sulindac is different.

Aged↗
PubMed1993

Cytogenetic analysis of intestinal polyps in polyposis syndromes: comparison with sporadic colorectal adenomas.

Few cytogenetic studies of polyps from patients with polyposis syndromes have been reported. We studied 27 colonic adenomatous polyps from familial adenomatous polyposis (FAP), two polyps of the small bowel from Peutz-Jeghers syndrome (PJS), and four colorectal juvenile polyps from juvenile polyposis syndrome (JPS). The karyotypic results were compared with 32 sporadic colorectal adenomatous polyps. Nineteen colorectal adenomas had abnormal karyotypes; of these, five were from patients with FAP and 14 were sporadic adenomas. Numerical changes were the most frequent change (14 adenomas); additional copies of chromosome 7 (eight adenomas) and 13 (seven adenomas) occurred most often and were present in both FAP and sporadic adenomas. Only five adenomas, all sporadic, had structural chromosome abnormalities. Normal karyotypes were obtained from 32 adenomas, and chromosome counts but not karyotypes were obtained from eight polyps owing to poor chromosome morphology. The JPS and PJS polyps had normal karyotypes. These data indicate that adenomas from patients with FAP tend to have fewer structural abnormalities than sporadic adenomas and that numerical abnormalities are the most common chromosome abnormality in both FAP and sporadic polyps and suggest that the mechanism which causes loss of heterozygosity (LOH) in the adenoma to carcinoma sequence operates on a level below that of the whole chromosome.

Adenomatous Polyposis Coli↗
PubMed2006

Serum insulin levels and the prevalence of adenomatous and hyperplastic polyps in the proximal colon.

BACKGROUND & AIMS: Obesity and diabetes mellitus are associated with an increased incidence of proximal colon cancer. Colonic adenoma that has been reported to be associated with elevated serum insulin levels and subsets of hyperplastic polyps might serve as a precursor of colon cancer. In this study, we sought to determine segment-specific associations between serum insulin levels and the prevalence of adenoma and hyperplastic polyps in the proximal and distal colon. METHODS: We studied 343 consecutive patients who underwent colonoscopy in our hospital. All medical information, including fasting serum insulin, was obtained at colonoscopy. We performed multinomial logistic regression models by using the outcome categories of none (reference), proximal-only, distal-only, and both-segment lesions for the presence of adenoma/hyperplastic polyp with serum insulin, age, gender, lifestyle characteristics, and the presence of other types of lesions as predictors. Odds ratios (ORs) and 95% confidence intervals (CIs) are provided for a 5-muU/mL increase in serum insulin. RESULTS: Overall, serum insulin levels were significantly associated with adenoma (OR, 1.5; 95% CI, 1.1-2.0; P = .005) and borderline associated with hyperplastic polyps (OR, 1.3; 95% CI, 1.0-1.7; P = .075). In multinomial logistic regression models, elevated serum insulin levels were significantly associated with proximal-only adenoma (OR, 1.8; 95% CI, 1.2-2.5; P = .002), both-side hyperplastic polyp (OR, 1.7; 95% CI, 1.1-2.5; P = .015), and proximal-only hyperplastic polyp (OR, 1.5; 95% CI, 1.0-2.1; P = .048) and borderline associated with distal-only adenoma (OR, 1.5; 95% CI, 1.0-2.1; P =.059) but not with distal-only hyperplastic polyp. CONCLUSIONS: Serum insulin levels directly correlate with the presence of adenoma and hyperplastic polyps in the proximal colon and might also less strongly correlate with the presence of distal adenoma.

Adenomatous Polyposis Coli↗
PubMed2006

Hysteroscopic evaluation of endometrial polyps.

OBJECTIVE: To establish the validity of hysteroscopy for predicting cancer in endometrial polyps based on their number, size and hysteroscopic appearance. METHOD: Retrospective observational study of 653 women diagnosed hysteroscopically as having endometrial polyps. After outpatient or surgical hysteroscopic resection or resection following hysterectomy, the diagnosis was confirmed by histological examination. The incidence of cancer in women who had polyps was determined in the light of menopausal status, symptoms, size, number and appearance of the polyps. RESULT: Carcinoma was found in only 3.9% of the women who consulted for menopausal metrorrhagia and were diagnosed as having a polyp. Hysteroscopy had a sensitivity of 36% and a specificity of 98% for a diagnosis of cancerous polyp or atypical hyperplasia. CONCLUSION: The appearance and number of endometrial polyps seen by hysteroscopy may be useful in predicting cancer in the polyps, although resection and histological examination will still be necessary to confirm the diagnosis.

Endometrial Neoplasms↗
PubMed2006

Expression and localisation of kinin receptors in colorectal polyps.

Kinins increase vascular permeability as well as mitogenesis and proliferation, hence they have a potential to promote neoplasmatic transformation. In the present study we investigated the expression profile and localization of kinin B1 and B2 receptors in colorectal polyps. The biopsy samples from various polyps were obtained during endoscopy in tubular (n=18), villous (n=15) and hyperplasic polyps (n=15). The expression of genes encoding B1 and B2 was estimated by QRT-PCR TaqMan analysis. In second series B1 and B2 receptors were visualized by immunohistochemical staining in tissue specimens from colonic polyps and adjacent normal tissue. We found the highest expression of gene encoding B1 in tubular adenomas (1891 number of copies mRNA/microg total RNA+/-312 SE) which is significantly higher as compared with controls (683+/-197 SE, p<0.013). In contrast, the expression of gene for B2 was significantly increased in hyperplastic polyps (3852+/-936 SE) as compared with controls (843+/-263 SE, p<0.0016). In normal colon a well as in hyperplasic polyps B1 and B2 receptors were immunohistochemically localized in enterocytes, however in hyperplastic polyps the intensity of staining was more prominent for B2 comparing to the control group. In contrast, in tubular adenomas staining reaction for B1 was more intense than in control samples. Increased level of B1 in adenoma suggests that kinins may play a role in abnormal cellular transformation; whereas higher B2 level in hyperplasic polyp suggests its protective role. Our data may indicate that the overall effect of kinins on cellular proliferation depends on the relative level of B1 and B2 receptor expression.

Adenoma↗
PubMed2003

Nasal mucosal gene expression in patients with allergic rhinitis with and without nasal polyps.

BACKGROUND: Nasal polyps are a common problem that is difficult to diagnose and treat, in part because the cause of nasal polyposis is unknown. Although information on the pathogenesis of polyposis is lacking, there are reports suggesting that a genetic predisposition underlies this disorder. OBJECTIVE: We sought to better understand the basis of nasal polyposis associated with allergic rhinitis. We hypothesize that the expression of unique genes is associated with the nasal polyposis phenotype. METHODS: We examined 12000 human genes transcribed in the nasal mucosa of patients with allergic rhinitis with and without nasal polyps. Biopsy specimens of the mucosa of patients with and without polyps were obtained after the patients refrained from the use of topical or systemic steroid therapy for 2 weeks. RESULTS: Thirty-four genes were differentially expressed between the patient groups, including those for inflammatory molecules and putative growth factors. The greatest differential expression identified by the array analysis was for a group of genes associated with neoplasia, including mammaglobin, a gene transcribed 12-fold higher in patients with polyps compared with control patients with rhinitis alone. Quantitative RT-PCR confirmed this differential expression and documented that the number of mammaglobin mRNA copies is actually 64-fold greater in tissues of patients with polyps versus control patients. The specificity of mammaglobin protein expression was evaluated by means of immunohistochemistry, which showed specific staining in nasal polyp mucosal goblet cells only in patients with polyps. CONCLUSION: These data suggest that nasal polyposis involves deregulated cell growth, using gene activation in some ways similar to a neoplasm. In addition, mammaglobin, a gene of unknown function associated with breast neoplasia, might be related to polyp growth.

Adult↗
PubMed2004

Gene profiling reveals increased expression of uteroglobin and other anti-inflammatory genes in glucocorticoid-treated nasal polyps.

BACKGROUND: Treatment with local glucocorticoids (GCs) decreases symptoms and the size of nasal polyps. This might depend on the downregulation of proinflammatory genes, as well as the upregulation of anti-inflammatory genes. OBJECTIVE: We sought to identify GC-regulated anti-inflammatory genes in nasal polyps. METHODS: Affymetrix DNA microarrays were used to analyze the expression of 22,283 genes in 4 nasal polyps before and after local treatment with fluticasone (400 microg/d). Expression of uteroglobin and mammaglobin B was analyzed with real-time PCR in 6 nasal polyps and in nasal biopsy specimens from 6 healthy control subjects. RESULTS: Two hundred three genes had changed in expression in treated polyps, and 139 had known functions: 54 genes were downregulated, and 85 were upregulated. Genes associated with inflammation constituted the largest single functional group. These genes affected key steps in inflammation (eg, immunoglobulin production; antigen processing and presentation; and the chemoattraction and activation of granulocytes, T cells, and B cells). Several proinflammatory genes were downregulated. In contrast, some anti-inflammatory genes were upregulated. The gene that increased most in terms of expression was uteroglobin. This was confirmed with real-time PCR. By contrast, expression of uteroglobin was lower in untreated polyps than in healthy nasal mucosa. Immunohistochemical investigation showed staining of uteroglobin in the epithelium and in seromucous glands in control subjects and in nasal polyps. CONCLUSION: Upregulation of anti-inflammatory genes, such as uteroglobin, might contribute to the effects of local treatment with GCs in nasal polyps.

Adult↗
PubMed2004

Dynamics of COX-2 in nasal mucosa and nasal polyps from aspirin-tolerant and aspirin-intolerant patients with asthma.

BACKGROUND: Only dynamic studies can elucidate the discrepancies concerning the expression of the inducible COX-2 gene in inflammatory airway diseases. OBJECTIVES: To quantify the expression and spontaneous regulation of COX-1 and COX-2 mRNAs in nasal polyps and nasal mucosa by real-time PCR. METHODS: Nasal polyps were obtained from 16 aspirin-tolerant patients with asthma/rhinitis (ATAR) and 18 aspirin-intolerant patients with asthma/rhinitis (AIAR) undergoing nasal polypectomy. Nasal mucosa was obtained from 12 subjects undergoing nasal corrective surgery. All specimens were cut into 3 pieces. One was immediately snap-frozen in liquid nitrogen, and the remaining 2 were left at room temperature for 30 or 60 minutes before freezing. Data are presented as medians and 25th to 75th percentiles of 10 6 cDNA molecules/microg total RNA. RESULTS: Baseline COX-2 mRNA levels were significantly lower in both ATAR (0.45; 0.13-1.20; P <.05) and AIAR (0.24; 0.12-0.41; P <.001) nasal polyps than in nasal mucosa (1.35; 0.52-3.90). COX-2 mRNA expression did not change over time in nasal mucosa but increased significantly in ATAR nasal polyps ( P <.05), reaching similar levels to nasal mucosa after 60 minutes. In contrast, COX-2 mRNA showed no significant change over time in AIAR nasal polyps. COX-1 mRNA was higher in nasal polyps than in nasal mucosa, and its expression was not modified over time in any group of patients. CONCLUSION: These results suggest differential kinetics of COX-2 mRNA between nasal mucosa and nasal polyps. AIAR nasal polyps appear to have a greater abnormality of the COX-2 pathway than ATAR.

Adult↗
PubMed2004

Immunohistochemical expression of estrogen and progesterone receptors in endometrial polyps and adjacent endometrium in postmenopausal women.

OBJECTIVE: To detect the presence of estrogen (ER) and progesterone (PR) receptors in endometrial polyps and adjacent endometrium in postmenopausal women. METHODS: Forty-four consecutively enrolled postmenopausal patients were submitted to operative hysteroscopy. These patients had diagnosed benign endometrial polyp. The presence of ER and PR was determined in endometrial samples and polyps by immunohistochemical method and the slides were evaluated using a semiquantitative analysis. RESULTS: In the glandular epithelium, the median of the ER score was 7.0 in the polyps and 5.0 in the endometrium (P<0.0001) and the median of the PR was 6.0 in the polyps and 4.0 in the endometrium (P<0.0001). In the stroma, the median of the ER score was 6.0 in the polyps and 5.0 in the endometrium (P=0.021) and the median of the PR score was 4.0 in the polyps and 4.5 in the endometrium (P=0.34 ). CONCLUSIONS: Our data suggests that steroids receptors present a crucial role in the phisiopathology of the endometrial polyps in postmenopausal women, specially the estrogen receptors.

Aged↗
PubMed1996

The difference in colon polyp size before and after removal.

BACKGROUND: Accurate knowledge of polyp size is important in assessing cancer risk in both clinical studies and individual patients. We sought to determine if a difference exists between the endoscopic estimation of colon polyp size and the actual measurement after removal. METHODS: We measured polyps in a systematic fashion. Using open biopsy forceps as a guide, the largest diameter of 31 pedunculated polyps was estimated endoscopically. The polyp was then removed by snare polypectomy and directly measured by a technician who was blinded to the endoscopic estimate. Each polyp was also measured after formalin fixation by a pathologist who was blinded to previous measurements. RESULTS: There was a significant difference between the endoscopic estimates and the postpolypectomy measurements. Endoscopic estimates on average were 1.6 mm greater than the postpolypectomy measurements (p< 0.05), representing an 18% difference. Twenty-three of the 31 (74%) endoscopic estimates were larger than the postpolypectomy measurements. There was not a significant difference between the postpolypectomy and postfixation measurements. CONCLUSIONS: The size of polyps measured endoscopically is significantly larger on average than postpolypectomy measurements. This is most likely due to factors involved in the removal of the in vivo polyp.

Adult↗
PubMed1994

Genitourinary polyps in children.

OBJECTIVES: This study was undertaken to review the presenting complaints, diagnostic evaluation, treatment, and natural history of children with genitourinary polyps seen at the Mayo Clinic during the past 35 years. METHODS: We retrospectively reviewed the charts of all children less than 16 years of age with symptomatic genitourinary polyps who were seen at the Mayo Clinic between 1957 and 1992. The age of each patient, clinical presentation, anatomic location of the polyp, diagnostic evaluation, and treatment were reviewed. Long-term follow-up data, including complications, were recorded, and the literature was reviewed. RESULTS: The most common presenting symptoms were hematuria in 9 patients, (gross 7, microscopic 2) and urinary tract obstruction in 9 patients (upper tract 3, lower tract 6). Four children had ureteral polyps. Excretory urography showed hydronephrosis and filling defects in 3 patients and a filling defect without hydronephrosis in 1 child. Two patients underwent segmental ureterectomy, 1 had open excision of the polyp, and 1 had ureteroscopic excision. Urethral polyps were identified in 12 children, most often as a filling defect of the posterior urethra on voiding cystourethrography (5 patients) or during cystourethroscopy (7 patients). All 12 patients were managed successfully by transurethral resection. CONCLUSIONS: Genitourinary polyps in children require a high degree of alertness and can be diagnosed with excretory urography, with voiding cystourethrography, or endoscopically. The biologic activity of these polyps is uniformly benign, and there have been no recurrences following complete excision.

Adolescent↗
PubMed1997

Cultured nasal polyps from nonatopic and atopic patients release RANTES spontaneously and after stimulation with phytohemagglutinin.

BACKGROUND: Eosinophil infiltration of tissue is a hallmark of nasal polyposis in both nonatopic and atopic patients. These cells are thought to play a key role in the nasal polyp inflammatory process. OBJECTIVE: The objective of this study was to investigate whether cultured nasal polyps derived from nonatopic and atopic patients release RANTES both spontaneously and after phytohemagglutinin (PHA) stimulation. METHODS: Nasal polyps were obtained from 12 subjects (6 nonatopic and 6 atopic), cut into 2 to 3 mm large specimens, and cultured for 48 hours with or without PHA. RANTES was measured in the culture supernatant by ELISA (R&D Systems, U.K.). RESULTS: Immunoreactive RANTES was found to be present in the culture supernatant of nasal polyps derived from both nonatopic and atopic patients with no difference between the two groups (median: 3.8 vs 2.9 pg/mg/ml). On incubation with PHA, nasal polyps from both nonatopic and atopic patients released sevenfold and 11-fold greater amounts of RANTES than unstimulated samples. As determined by immunohistochemistry, RANTES was localized to the vascular endothelium in nasal polyps from both groups of patients. CONCLUSIONS: This study demonstrates that cultured nasal polyps derived from both nonatopic and atopic patients release RANTES spontaneously and after PHA stimulation. This observation and the finding that RANTES is present in nasal polyp endothelial cells suggest that this chemokine may be an important mediator of eosinophil and lymphocyte recruitment in both nonatopic and atopic nasal polyposis.

Adult↗
PubMed1995

Differentiation of focal foveolar hyperplasia from hyperplastic polyps in gastric biopsy material.

Our objective was to investigate the question as to whether focal foveolar hyperplasia and hyperplastic polyp can be differentiated in forceps biopsy material from the stomach. Morphometric determination of the height of the epithelium layer in forceps biopsy specimens was obtained from 35 hyperplastic polyps, and forceps biopsy material was obtained from 25 focal foveolar hyperplasias. The diagnosis of hyperplastic polyp was confirmed by subsequent polypectomy. The medians and scatter range of the epithelial layer height were calculated. Using the t-test for independent samples the question was examined as to whether there is any statistically significant difference between hyperplastic polyps and focal foveolar hyperplasia in terms of the parameter "height of the foveolar epithelial layer." The measurements revealed that the average height of foveolar epithelial cells in hyperplastic polyps is 37.70 microns +/- 7.41 microns. In the case of focal foveolar hyperplasia, the corresponding figure was only 24.26 microns +/- 5.11 microns. This difference was statistically highly significant (p < 0.0001). In conclusion, focal foveolar hyperplasia and hyperplastic polyp of the gastric mucosa can readily be differentiated on the basis of architectural and cytological criteria, even in forceps biopsy material. Since the hyperplastic polyp very probably does not evolve from focal foveolar hyperplasia, and the latter is not a pre-neoplastic condition or lesion, it is proposed that focal foveolar hyperplasia should no longer be referred to as "gastric polyp," which would avoid unnecessary follow-up examinations and possibly even surgery.

Diagnosis, Differential↗
PubMed2002

Diminutive polyps of large bowel should be an early target for endoscopic treatment.

BACKGROUND AND AIMS: Aim of the present study is to ascertain the importance of diminutive colorectal polyps and define the need for removal according to their characteristics and malignant potential. PATIENTS AND METHODS: A total of 4,723 patients who underwent colonoscopy were evaluated and 624 patients with 826 polyps were recorded. There were 352 patients with 443 diminutive polyps, studied according to their distribution. Of these, 371 were removed, histologically examined and correlated to patient characteristics and occurrence of synchronous neoplasms. RESULTS: Of the right colon polyps, 81/115 were diminutive, versus 362/711 of the left colon (p<0.0001). Adenomas were more common in patients over 50 years of age, (p<0.0001). In all colonic segments, diminutive adenomas prevailed over hyperplastic polyps, whereas the proportion of diminutive adenomas predominated in the right colon (p=0.0015). Adenomas were classified as tubular 39%, tubulovillous 55.7% and villous 5.3%. The degree of dysplasia was mild in 45.5%, moderate in 51% and severe in 3.5%. The prevalence of synchronous neoplasms was 37.4%. They were more frequently found in males over 50 years of age and in patients with diminutive adenomas compared to those with diminutive hyperplastic polyps (p=0.0078). CONCLUSIONS: The majority of right colon polyps are diminutive. The proportion of diminutive adenomas is higher in patients over 50 years and in the right vs left colon. Diminutive polyps should be removed taking into account the high prevalence of adenomas with a villous component and their significant degree of dysplasia.

Adenomatous Polyposis Coli↗
PubMed1997

Mast cell ultrastructure in the inferior turbinate and stroma of nasal polyps.

Fourteen unselected adult patients with nasal polyps had ultrastructural examination of mast cells from matching biopsies of the polyp and inferior turbinate. Between three and 10 blocks were examined for each patient in both tissues and every mast cell that had a nucleus was photographed for study. Fifty-three mast cells were found within the stroma of nasal polyps and 54 in the submucosa of the inferior turbinate biopsies. The number of granules ranged between 13 and 167 (mean 60) for polyps and 18 and 148 (mean 61) in the inferior turbinate. The mast cells appeared essentially normal in the inferior turbinate of four patients. The degree of degranulation of the mast cells was calculated as in previous studies and then averaged for both the polyp and the inferior turbinate of each patient. There was greater degranulation in the nasal polyp compared to inferior turbinate (p = 0.03). These results were compared with mast cell degranulation found in the normal nose and in the inferior turbinate of patients with perennial allergic rhinitis which we previously published. The inferior turbinates in these patients were more degranulated than the normal nose (p = 0.0001) but were similar to that found in patients with perennial allergic rhinitis. This suggested that some degree of degranulation may occur throughout the nose in two thirds of the patients with nasal polyps which supports the theory that mast cell reactions are not limited to the polyps in a proportion of patients.

Adult↗