Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Polyps”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 955 records · Page 53Linked to original sources

[Endoscopic resection of 49 polyps of the colon and rectum larger than 2 cm].

The management of rectal and colonic polyps has changed since the advent of endoscopic polypectomy, that interrupts the adenoma-carcinoma sequence. We assessed the effectiveness, limitations, morbidity and mortality of endoscopic polypectomy in 49 polyps larger than 2 cm in diameter. Polypectomy was successful in 94% of polyps, which were predominantly located in left colon (92%) and were pedunculated (87%). A malignant component was found in 28.3% of polyps, that was observed with higher frequency in larger and sessile polyps and in male patients. There was no mortality and scarce morbidity related to the procedure. It is concluded that polypectomy is a low risk procedure that can be frequently performed in ambulatory patients and that endoscopists must suspect malignancy in polyps larger than 2 cm in diameter.

Adolescent↗

Metachronous colon cancer in persons who have had a large adenomatous polyp.

OBJECTIVE: To determine, among persons who have had a large colon polyp, the risk of subsequent colon cancer at a site distant from that polyp. METHODS: Follow-up was done for 226 persons at the Mayo Clinic who had had a > or = 1-cm polyp demonstrated on barium enema between 1965 and 1970 and for whom yearly colon surveillance examination was recommended. Information was collected from Mayo Clinic records and from contact with patients, physicians, and other hospitals regarding the results of surveillance examinations and the development of colon cancer. Colon surveillance was routinely done at the Mayo Clinic using the technique of single contrast barium enema with vigorous manual fluoroscopic examination and proctoscopy. The expected rate of colorectal cancer (CRC) was calculated based on previously published rates for this community. RESULTS: Patients received, on average, four colon examinations in addition to the examination that discovered the index polyp. During 2126 person-years of follow-up, 16 persons developed a colon cancer at a location other than the site of the index polyp, in comparison with 4.0 expected cases, for a standardized incidence ratio of 4.0 (95% CI,2.3, 6.4). The cancers were large (mean 4.5cm) at presentation, and eight of the 16 cancers had been preceded within 3 yr by at least one negative barium enema. CONCLUSIONS: The rate to develop colon cancer in persons who have had a large colon polyp es about 4 times the expected rate, suggesting that such persons should be considered for aggressive colonoscopic surveillance. The failure to detect early cancer or its precursors by surveillance barium enema is probably explained by inherent insensitivity of single contrast barium enema.

Adenomatous Polyps↗

Glycohistochemical characteristics of nasal polyps from patients with and without cystic fibrosis.

OBJECTIVE: To investigate whether cystic fibrosis (CF)-related nasal polyps exhibit significantly distinct glycohistochemical characteristics when compared with single vs massive nasal polyps obtained from patients without CF. DESIGN: Glycohistochemical characteristics were identified by means of 8 histochemical probes, including 5 plant lectins (peanut, gorse seed, wheat germ, Maackia amurensis, and Sambucus nigra agglutinins), 2 animal lectins (14- and 16-kd galectins), and 1 neoglycoprotein (exposing the Thomsen-Friedenreich antigen). The binding of the 8 glycohistochemical markers was determined by means of computer-assisted microscopy. For each probe, 3 quantitative parameters were computed: the labeling index, which describes the percentage of tissue area specifically stained by a given marker; the mean optical density, which reflects the staining intensity; and the concentrational heterogeneity, which characterizes the level of heterogeneity of the staining intensity. SUBJECTS: A series of 61 nasal mucosa specimens was analyzed, including 6 normal cases, 23 single and 18 massive polyposis cases without CF, and 14 nasal polyps associated with CF. RESULTS: Normal and polyposal nasal mucosa differed in terms of the amounts and linkage types of sialic acids (revealed by the wheat germ, M amurensis, and S nigra agglutinins) rather than the characteristics of galactoside expression (monitored with the peanut agglutinin and 2 animal galectins). In contrast, nasal polyps markedly differed between patients with and without CF with respect to galactoside expression (revealed by the peanut agglutinin and the 14-kd galectin) and the display of binding site(s) for the neoglycoprotein. CONCLUSION: Normal and polyposal nasal mucosa differ essentially in sialic acid presentation, while nasal polyps from patients with CF have a higher level of various lectin-reactive galactoside residues than nasal polyps from those without CF.

Cystic Fibrosis↗

Efficacy and tolerability of budesonide aqueous nasal spray treatment in patients with nasal polyps.

OBJECTIVE: To assess the efficacy and tolerability of once-daily treatment with budesonide aqueous nasal spray in patients with nasal polyps. DESIGN: Randomized, double-blind, placebo-controlled, parallel-group study. SETTING: Sixteen hospital clinics. PATIENTS: One hundred eighty-three patients with moderate-sized nasal polyps causing clinically significant symptoms during a 1-week run-in period. INTERVENTIONS: Patients were randomized to receive 1 of the following 4 budesonide aqueous nasal spray treatments: 128 microg once daily in the morning and placebo in the evening, 128 microg twice daily, 256 microg once daily in the morning and placebo in the evening, or placebo for 8 weeks. Nasal polyp size was scored and peak nasal inspiratory flow was measured at clinic visits at the beginning and end of the run-in period and after 4 and 8 weeks' treatment. Patients recorded daily peak nasal inspiratory flow, symptom scores (ie, blocked nose, runny nose, and sneezing) and sense of smell on diary cards. MAIN OUTCOME MEASURES: Mean change in nasal polyp size at the end of treatment; mean changes in combined and individual symptom scores. RESULTS: All doses of budesonide aqueous nasal spray significantly (P<.01) reduced polyp size; no significant differences were noted between the 4 treatment groups. The mean improvement in clinic peak nasal inspiratory flow at 8 weeks was 65.9 L/min with budesonide aqueous nasal spray, 128 microg twice daily; 71.6 L/min with budesonide aqueous nasal spray, 256 microg once daily; and 54.6 L/min with budesonide aqueous nasal spray, 128 microg once daily (all P<.001 vs placebo). Combined and individual symptom scores and sense of smell improved significantly in all budesonide-treated groups; the effect on symptoms became apparent within 1 to 2 days of the first dose. Budesonide aqueous nasal spray was well tolerated. CONCLUSIONS: Doses of budesonide aqueous nasal spray, 128 microg once daily, were found to be effective in the treatment of nasal polyps, and doses of budesonide aqueous nasal spray, 256 microg once daily, did not show any significant additional efficacy.

Administration, Intranasal↗

Increased epithelial cell proliferation in nasal polyps.

OBJECTIVE: To detect, quantify, and compare respiratory epithelial cell proliferation in nasal mucosa and polyps from patients with nasal polyposis. DESIGN: Cohort study. SETTING: Patients and samples were selected at the Hôpital Intercommunal de Créteil (France). Flow cytofluorometry and immunohistochemistry were performed at Hôpitaux Tenon and Mondor (Université Paris [France] VI et XII). PATIENTS: Twenty-one patients undergoing endoscopic ethmoidectomy for treatment of nasal polyposis. METHODS: In 10 cases, epithelial cells were removed from frozen inferior turbinate mucosa and polyps by mechanical disaggregation and were then analyzed by flow cytofluorometry, providing the cell DNA content (propidium iodide labeling) and the percentage of S-phase cells. In 11 cases, inferior turbinate mucosa and polyps were fixed in formaldehyde and embedded in paraffin. Proliferating cell nuclear antigen expression in the epithelium was quantified by immunohistochemistry; a proliferating cell nuclear antigen index was calculated for each sample in the basal area, suprabasal area, and full height of the epithelium. RESULTS: All cell populations studied were diploid, and percentages of S-phrase cells were significantly higher in nasal polyps than in mucosa. Proliferating cell nuclear antigen indexes were significantly higher in nasal polyps than in the suprabasal area and full height of the mucosal epithelium. CONCLUSION: Cell proliferation is increased in epithelium from nasal polyps. Epithelial damage caused by inflammatory mediators could induce this increased cell proliferation via epithelial repair processes. Inflammatory cells could up-regulate epithelial cell proliferation by secreting growth factors.

Cell Division↗

Aberrant expression of MUC5AC and MUC6 gastric mucin genes in colorectal polyps.

Altered mucin glycosylation and the de novo appearance of gastric mucin antigens have been described in colonic adenomas. The purpose of our study was to determine if expression of the gastric mucin genes MUC5AC and MUC6 occurs in colorectal adenomas and whether this correlates with histopathologic criteria of malignant potential. Immunohistochemical staining using antibodies against MUC5AC and MUC6 tandem repeat synthetic peptides was performed on specimens of normal colon mucosa (n = 26), hyperplastic polyps (n = 9) and adenomatous polyps (n = 111). Mucin mRNA levels were determined using RNase protection assays using riboprobes corresponding to unique non-repetitive sequences. MUC5AC and MUC6 staining were rarely detected and of low intensity in normal colon and hyperplastic polyps. The number of immunoreactive polyps and intensity of MUC5AC and MUC6 staining were greatest in larger adenomas of moderate villous histology and dysplasia. MUC5AC and MUC6 staining tended to decrease in highly villous polyps with severe dysplasia. Increased MUC5AC mRNA levels were found in 26/45 of adenomas tested compared with 0/9 normal colon specimens. MUC6 mRNA levels were found in 20/45 of adenomas compared with 1/9 normal colon specimens. MUC5AC and MUC6 mRNA were present more frequently and at higher levels in polyps with intermediate stages of size, villous histology and dysplasia. We conclude that aberrant expression of MUC5AC and MUC6 mucin genes is likely responsible for an expanded repertoire of mucin antigen expression in colorectal neoplasia.

Adenomatous Polyposis Coli↗

The demonstration of carcinoembryonic antigen in colorectal carcinoma and colonic polyps using an immunoperoxidase technique.

Carcinoembryonic antigen (CEA) has been demonstrated in tissues, by immunofluorescence, with conflicting results. Originally thought to be persent in colorectal carcinoma only, the antigen was later demonstrated in inflamed colonic mucosa and polyps. Using formalin-fixed, paraffin-embedded tissues and an immunoperoxidase technique, we have attempted to demonstrate CEA in 12 colorectal carcinomas, in adjacent benign mucosa, and in 42 polyps of varying histologic type. CEA was demonstrated in all colorectal cancers but not in adjacent inflamed mucosa. The antigen could not be demonstrated in polyps except in five cases where CEA was shown in morphologically atypical glands only. With out technique, the demonstration of CEA is a reliable indicator of malignant change in colonic mucosa. The findings in polyps tend to support the concept of carcinoma in situ in adenomatous polyps and the polyp-cancer sequence.

Adenocarcinoma↗

Interobserver variability in the pathological assessment of malignant colorectal polyps.

BACKGROUND: Treatment of patients with malignant large bowel polyps is highly dependent on pathological evaluation. The aim of this study was to evaluate interobserver variability in the pathological assessment of endoscopically removed polyps. METHODS: The records of 88 patients with colorectal cancer who underwent endoscopic removal of malignant polyps were reviewed. Study investigators reviewed the initial pathology report; three experienced gastrointestinal pathologists reviewed all slides in a blinded fashion. Interobserver variability of pathological assessment of malignant polyps was analysed by kappa statistics. RESULTS: Seventy-six (86 per cent) of the 88 patients had malignant polyps and 12 (14 per cent) had carcinoma in situ. Agreement between experienced pathologists was substantial with regard to T stage (kappa = 0.725), resection margin status (kappa = 0.668) and Haggitt's classification (kappa = 0.682), but comparison of initial and experienced pathologists' assessment demonstrated only moderate agreement in these areas (kappa = 0.516, kappa = 0.555 and kappa = 0.578 respectively). Agreement between even experienced pathologists was poor with respect to histological grade of differentiated adenocarcinomas (kappa = 0.163) and angiolymphatic vessel invasion (kappa = - 0.017). CONCLUSION: Pathological assessment of malignant polyps varies between observers. Specialist pathologists appear to have a higher degree of consensus among themselves than with generalist pathologists with respect to T stage. The high interobserver variability with regard to histological grade of differentiated tumours is clinically irrelevant. However, variability in the assessment of angiolymphatic vessel invasion limits the value of this measurement for clinical decision making.

Adult↗

K-ras mutation in tamoxifen-related endometrial polyps.

BACKGROUND: K-ras mutation is thought to occur at an early stage of neoplastic progression in the endometrium. The authors investigated mutations in codon 12 of K-ras in tamoxifen (TAM)-related endometrial polyps. METHODS: DNA was extracted from 11 frozen endometrial polyps from TAM-treated patients with breast carcinoma. Mutations were detected using the mutant allele-specific amplification method. The results subsequently were analyzed for correlations with immunohistochemical data that were obtained using antibodies against estrogen receptors (ERs; alpha and beta forms), progesterone receptors (PRs; A and B forms), and Ki-67. RESULTS: Mutations in codon 12 of K-ras were observed in 7 of 11 TAM-related endometrial polyps. Expression levels of ER-alpha and PR-B were high in the glandular epithelium and low in the stroma. PR-A expression was high in both the glandular epithelium and the stroma. In the glandular epithelium, expression of ER-beta appeared to be lower than expression of ER-alpha. The Ki-67 index in the glandular epithelium ranged from 2 to 38, whereas the index ranged from 0 to 4 in the stroma (P < 0.01). CONCLUSIONS: The incidence of mutations in codon 12 of K-ras in TAM-related endometrial polyps (64%) was greater than the incidence of these same mutations in sporadic endometrial hyperplasias (4.5-23%). High expression levels of ER-alpha, PR-A, and PR-B in the glandular epithelium were observed in all polyps, regardless of K-ras codon 12 mutation status and Ki-67 index. The authors' findings may support the hypothesis that the polyp-carcinoma sequence partly indicates the development of endometrial carcinoma in postmenopausal women who have been treated with TAM.

Aged↗

Incidence of colorectal cancer following adenomatous polyps of the large intestine.

An association between adenomatous polyps of the large bowel and colorectal cancer has been reported, in the absence, however, of population-based estimates of risk. Subjects with histologically confirmed first diagnosis of large-bowel polyps notified to the population-based Cancer Registry of the Swiss Canton of Vaud (about 600,000 inhabitants) during the calendar period 1979-1990 were actively followed up to the end of 1990 for the subsequent occurrence of malignant neoplasms. Among 2,496 individuals with intestinal polyps, followed for a total of 10,310 person-years at risk (6,201 among males and 4,109 among females), 150 malignant neoplasms were registered versus 152 expected. Thus, the standardized incidence ratio (SIR) for all cancers combined was 0.99. A significant excess was observed for colorectal cancer, with 35 cases observed (19 males, 16 females) versus 17.0 expected (SIR = 2.1; 95% CI: 1.5-3.0). There was also an excess, although not significant, for small-bowel cancer (2 cases observed vs. 0.4 expected; SIR = 5.4). In none of the other cancer sites was SIR significantly or appreciably elevated: in subjects with colorectal polyps the SIR was 1.6 for stomach, 1.0 for lung, 0.9 for breast and 1.2 for prostate. The SIR of colorectal cancer was 3.1 in the first year since polyp registration, and declined thereafter to 1.8, in the absence, however, of any further trend with time since diagnosis. The cumulative risk of colorectal cancer in subjects with colorectal polyps was 2% at 5 years and 3% at 10 years. The quantitative estimates of this study are of interest for their population-based nature, and are potentially useful for defining and targeting screening colonoscopy programmes.

Adult↗

Inflammatory endobronchial polyps in childhood: clinical spectrum and possible link to mechanical ventilation.

Inflammatory polyps of the airways are now regarded as histopathologically distinct nonneoplastic endobronchial lesions, which in adults are associated with a variety of chronic inflammatory insults. However, their clinical presentation in the pediatric population is extremely rare, with the etiology of such polyps poorly defined. The clinical and histopathological data from four pediatric patients, identified in the histopathology files of the Royal Brompton Hospital, were retrospectively reviewed. Three out of 4 patients had a history of mechanical ventilation in the neonatal period. In these 3 patients, the polyps were all situated in the proximal airways on the right side. These 3 patients presented at 6 weeks, 7 weeks, and 2 years, respectively, and were successfully treated by polypectomy at rigid bronchoscopy, with subsequent return to normality. One patient, presenting at 12 years of age without history of iatrogenic intervention, underwent a left lower lobectomy for a polyp sited in a segmental bronchus. Presentation in 3 of the 4 patients was with lobar collapse. The fourth patient presented with hyperinflation. We conclude that inflammatory endobronchial polyps may be associated with a history of mechanical ventilation in the neonatal period, polyp formation perhaps being secondary to airway trauma. The small caliber of the main airways in neonates may also be a contributory factor in presentation.

Bronchial Neoplasms↗

Immunohistochemical demonstration of IgA and secretory component in relation to epithelial cell differentiation in normal colorectal mucosa and metaplastic polyp: a semiquantitative study.

The metaplastic polyp is a non-neoplastic epithelial lesion found within the human colorectum. Although not regarded as precancerous, recent studies have demonstrated the expression of multiple cancer-associated phenotypes. This might indicate a possible indirect relationship between metaplastic polyps and colorectal cancer. Epithelial secretory component and IgA were demonstrated by the immunoperoxidase technique and staining intensities were assessed semiquantitatively. The findings were related to cellular differentiation in normal colorectal epithelium as compared to the metaplastic polyp. The crypt base cells and also the surface epithelial cells stained with similar intensity in both types of epithelium. However, the expected increase in staining characterizing normal lower and upper crypt columnar cells and reduction in staining associated with the switch from crypt to surface columnar cell was not observed in the metaplastic polyp. Metaplastic crypt columnar cells showed significantly reduced staining for both IgA and secretory component as compared to their normal counterparts. There was also a significant reduction in the number of IgA-secreting plasma cells in the lamina propria of the metaplastic polyp. These findings are consistent with the concept of a premature switch to mature surface cell characteristics within the metaplastic polyp. They are discussed in the light of other changes in phenotype associated with this lesion.

Colon↗

Effect of diet on fecal occult blood testing in patients with colorectal polyps.

To determine the effect of a red-meat-free, high-fiber diet, patients performed fecal blood testing before colonoscopy for suspected polyps. One hundred twenty-nine patients were allowed an unrestricted diet, and 159 consumed the special diet. Without dietary restrictions, 31 of 77 patients with adenomas, five of eight with cancer, one of seven with nonneoplastic polyps, and one of 37 with normal colonoscopy had positive tests. With the special diet, 30 of 97 patients with adenomas, eight of ten with cancer, one of six with nonneoplastic polyps, and one of 46 with normal colonoscopy had positive tests. There are no statistical differences between the groups. Comparing all patients with cancer to those with normal colonoscopy, the sensitivity of fecal blood testing is 72%, the specificity 98%, and the positive and negative predictive value 87% and 94%, respectively. The sensitivity for fecal blood testing in patients with adenomas (compared to those with normal endoscopy) is 35%, the specificity is 98%, and the positive and negative predictive values are 97% and 42%, respectively. Combining all patients with adenomas, those with multiple polyps, larger polyps, or polyps located distal to the splenic flexure had positive fecal blood tests more frequently. Fecal blood testing does not detect a large number of colorectal adenomas. This study does not indicate any benefit on the sensitivity or specificity of fecal blood tests from the red-meat-free, high-fiber diet currently recommended.

Adenoma↗

Adenomatous and hyperplastic polyps cannot be reliably distinguished by their appearance through the fiberoptic sigmoidoscope.

This prospective study is designed to determine if experienced sigmoidoscopists can, from gross appearance, differentiate adenomas and hyperplastic polyps. Six hundred eleven polyps discovered at fiberoptic sigmoidoscopy were removed completely or biopsied for histologic examination. The polyp's size, distance from the anal verge, color, and the endoscopist's diagnosis were analyzed. Hyperplastic polyps were significantly smaller, of lighter color, and located closer to the anus than adenomas. The sensitivity of the endoscopic diagnosis for adenomas is 0.80 and the specificity 0.71. We conclude the endoscopic diagnosis of polyps 1.0 cm and smaller is not accurate enough for decision making, and these should be biopsied to guide management. Since 97% of polyps larger than 1.0 cm are adenomas, their removal can be advised without biopsy.

Adenoma↗

Gastric hamartomatous polyp without polyposis coli: radiologic diagnosis.

Gastric hamartomatous polyps were found in 25 patients over a period of 4 1/2 years, for an incidence of 11% in all endoscopically biopsied polyps. The number of polyps was fewer than 5 in most patients. All polyps were sessile, sharply demarcated, hemispheric protrusions, measuring up to 10 mm in diameter but most were less than 5 mm. The most characteristic finding differing from hyperplastic polyps, adenoma, and polypoid carcinoma was that hamartomatous polyps were located in the fundic gland mucosa, which was demonstrated as a rugal area on moderately distended double-contrast radiographs.

Adult↗

The risk of lymph node metastasis in colorectal polyps with invasive adenocarcinoma.

One hundred fifty-one patients with colorectal polyps containing invasive adenocarcinoma treated by resection were studied to determine the incidence of lymph node metastasis and whether lymph node metastasis was related to the depth of invasion. Other variables evaluated included size and configuration of the polyp, grade of adenocarcinoma, presence or absence of lymphovascular invasion, and degree of differentiation. In patients with sessile polyps, the incidence of lymph node metastasis was 10 percent. Eighty percent of these lesions had lymphovascular invasion. For pedunculated polyps, the overall incidence of lymph node metastasis was 6 percent. However, there was no incidence of lymph node metastasis when the depth of invasion was limited to the head, neck, and stalk of the polyp (Levels 1, 2, and 3). Only when the depth of invasion reached to the base of the stalk (Level 4) was the risk of lymph node metastasis high (27 percent). The other risk factors were not associated with lymph node metastasis. We concluded that the most significant risk factor for lymph node metastasis in patients with invasive carcinoma in a polyp was invasion into the submucosa of the bowel wall (Level 4).

Adenocarcinoma↗

Carcinoma in gastric hyperplastic polyps. A phenotypic study.

One-hundred twelve hyperplastic polyps were analyzed. The aim was to study their malignant transformation. Among them, four hyperplastic polyps harbored adenocarcinoma; two were from our own institution (1.8%). The majority were pedunculated and located in the antrum with an average of 14.5 mm in diameter. The four polyps bore well-differentiated adenocarcinoma. Dysplasia and intestinal metaplasia were detected in two and three polyps, respectively. The cancer and dysplastic foci shared the same type of neutral and acid mucosubstances. p53 oncoprotein was positive in three cancer foci and in the dysplastic areas, and nucleolar organizer region counts were higher in the cancer foci. In conclusion, hyperplastic polyps have malignant potential. Such possibility increases in polyps larger than 14.5 mm. In our cases, the carcinoma foci may have arisen from dysplastic areas. Once the neoplastic changes occur, the cancer cells proliferate and behave as other adenocarcinomas of the stomach.

Adenocarcinoma↗

Distribution of malignant polyps in the colon.

The purpose of this study was to investigate whether the distribution of malignant polyps of the colon is the same as the distribution of all polyps in general. A consecutive and unselected series of 1226 endoscopically removed polyps was analyzed; the analysis indicated a strong preponderance of malignant polyps to be located in the left side of the colon. Ninety-five per cent of the malignant polyps were taken distal to the splenic flexure, whereas that segment of the colon produced only 72 per cent of all of the polyps in general. It is not possible to determine the reason for this from the present study, but the importance of removing these polypoid lesions continues to be emphasized by these data.

Adolescent↗