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PubMed1984

[Hyperplasiogenic gastric polyps and stomach cancer. Endoscopic findings of early stomach cancer in 3 out of 42 biopsies of hyperplasiogenic polyps].

The hyperplasiogenic gastric polyp is an organo-specific polyp and compared to the real adenoma of the stomach and colon is not a neoplasia. The formation of a carcinoma in or on a hyperplasiogenic polyp is extremely rare. Hyperplasiogenic polyps have more of an indicator function, indicating an ill mucous tissue and the possibility of the formation of a carcinoma and a precancerous condition. Three observations of the formation of early carcinoma of the stomach in or on hyperplasiogenic polyps in 42 patients with hyperplasiogenic polyps, which were found in the upper alimentary tract in the course of 4 years and 10.473 endoscopic investigations, are reported here. Due to these observations the endoscopic loop extraction of all polypous protuberances still seems to be necessary.

Adenoma↗
PubMed1978

[Colorectal polyps. Pathologico-anatomical and statistical studies on 3037 polyps].

Report on 3037 colorectal polyps from the Deutsche Klinik für Diagnostik Wiesbaden that were observed within about 6 years and submitted to microscopic examination. The polyps were classified according to the WHO nomenclature, 1976. Adenomas and metaplastic (hyperplastic) polyps were the most frequenty types. The terms 'carcinoma in situ,' 'focal carcinoma,' 'adenoma with severe cellular atypia,' and 'malignant polyp' are explained and discussed in view of possible false interpretations by the surgeon. It is stressed that only the term 'adenoma with severe cellular atypia' (WHO classification) should be retained. In 286 cases, primary multiplicity of polyps was observed. There were recurrent polyp(s) in 154 cases (7%). Most frequently the recurrent polyp(s) corresponded to the type that had been found during the first examination. Finally, some remarks are made concerning the techniques of biopsy and of pathological examination.

Adenoma↗
PubMed1997

Gastric fundic gland polyps (Elster's polyps) and Helicobacter pylori-induced gastritis.

In a series of 555 gastric polyps characteristic Elster's polyps were identified in 31 cases. Spiral bacteria (Helicobacter pylori) in these polyps were sporadic, much less frequent (9.7%) than in hyperplastic polyps (35%) in the present series and in relation to the bacteria frequency found in our randomly chosen gastric biopsy specimens (43%). The present results indicate that Elster's polyps are not readily colonized by Helicobacter pylori and accordingly, they do not show the signs of active gastritis. The reasons for this are unknown. One of the mechanisms preventing from bacterial colonization may be a different from normal gastric mucosa and other polyps character of mucus produced by glandular neck cells, which was found in our series of gastric fundic gland polyps.

Adolescent↗
PubMed2001

Sporadic fundic gland polyps: common gastric polyps arising through activating mutations in the beta-catenin gene.

Fundic gland polyps (FGPs) are the most common gastric polyps. FGPs traditionally have been regarded as nondysplastic hamartomatous or hyperplastic lesions, but their pathogenesis remains unclear. We have recently shown that somatic adenomatous polyposis coli (APC) gene alterations are frequently present in FGPs associated with familial adenomatous polyposis (FAP), raising the possibility that mutations of the beta-catenin gene affecting the APC/beta-catenin pathway might be involved in the pathogenesis of sporadic FGPs. We analyzed somatic beta-catenin gene mutations in 57 sporadic FGPs from 40 patients without FAP and in 19 FGPs from 13 FAP patients. Direct DNA sequencing of exon 3 encompassing the glycogen synthase kinase-3beta phosphorylation region for beta-catenin was used with confirmation by HIN:fI restriction endonuclease digestion. The foveolar epithelium and dilated fundic glands of the polyps were separately microdissected and analyzed in 22 of 57 sporadic FGPs. Activating beta-catenin gene mutations were present in 91% (52 of 57) of sporadic FGPs. Both the foveolar epithelium and the dilated fundic gland epithelium comprising the polyps were shown to have the same somatic beta-catenin mutation in 21 of 22 (95%) sporadic FGPs. In contrast, beta-catenin gene mutations were not present in any of the 19 FAP-associated FGPs (P: < 0.000001). The high frequency of beta-catenin mutations in sporadic FGPs indicates that these lesions arise through activating mutations of the beta-catenin gene. Beta-catenin mutations in gastrointestinal tract polyps have previously only been demonstrated in a subset of adenomatous (dysplastic) or neoplastic polyps. Sporadic FGPs are therefore the only lesions of the gastrointestinal tract to demonstrate beta-catenin mutations while lacking dysplastic morphology.

Cytoskeletal Proteins↗
PubMed2002

Prolapsing mucosal polyps: an underrecognized form of colonic polyp--a clinicopathological study of 15 cases.

OBJECTIVE: Prolapsing intestinal mucosa occurs in many forms throughout the GI tract. We describe 15 patients with polypoid masses in the sigmoid colon and histological features of mucosal prolapse. METHODS: Fifteen patients with colon polyps demonstrating endoscopic and histological features of mucosal prolapse were retrospectively identified from our database. RESULTS: Twelve patients presented with signs and symptoms that were nonspecific, but consistent with mucosal prolapse, such as occult or gross intestinal bleeding and lower abdominal pain. Three patients were asymptomatic. The polyps occurred in the sigmoid colon, usually in association with diverticular disease, and appeared more often in men. Endoscopically, the polyps appeared to be well-circumscribed, hyperemic masses that contrasted sharply with normal-appearing adjacent mucosa. Histological features include glandular crypt abnormalities, fibromuscular obliteration of the lamina propria, and thickened and splayed muscularis mucosa. CONCLUSIONS: Prolapsing mucosal polyps of the colon are histologically similar to other mucosal prolapsing conditions in the GI tract, such as the solitary rectal ulcer syndrome, inflammatory cloacogenic polyps, inflammatory "cap" polyps, and gastric antral vascular ectasia, and should therefore be designated as part of the "mucosal prolapse syndrome."

Adult↗
PubMed2006

Expression of Bcl-2 and Ki-67 in tamoxifen-associated endometrial polyps: comparison with postmenopausal polyps.

BACKGROUND: The aim of this study was to evaluate the expression of Bcl-2 and Ki-67 in tamoxifen (TAM)-associated endometrial polyps and postmenopausal polyps. MATERIAL AND METHODS: For this purpose, a retrospective analysis of paraffin-embedded specimens was carried out. Polyps of 20 postmenopausal and 14 TAM-treated patients, 11 simple endometrial hyperplasia, 10 atypical complex endometrial hyperplasia and 8 endometrial adenocarcinoma specimens were included in the study. Hematoxylin/eosin-stained sections were evaluated. Immunohistochemical staining was performed to investigate the expression of Bcl-2 protein and the Ki-67 proliferation index. RESULTS: There was no statistically significant difference between the 5 groups with regard to Bcl- 2 staining (p > 0.05). However, Bcl-2 expression in TAM-associated polyps was higher (86%) than in the postmenopausal control group (80%). Positive Ki-67 was highest in the endometrial adenocarcinoma specimens, followed by the atypical complex endometrial hyperplasia group (p < 0.0001). Compared to these 2 groups, Ki- 67 expression was lower in TAM-associated polyps, but Ki-67 indexes were significantly higher in the TAM-associated group than in the control group (p < 0.0001). CONCLUSION: Since TAM-associated polyps tend to have higher proliferation indexes and Ki-67 ratios than control groups, we suggest that they are likely to have a higher malignant potential.

Endometrium↗
PubMed2002

Immunohistochemical study of myofibroblasts in normal colonic mucosa, hyperplastic polyps, and adenomatous colorectal polyps.

CONTEXT: Myofibroblasts are distinct cells with characteristics of both smooth muscle cells and fibroblasts. Through their ability to secrete cytokines, chemokines, prostaglandins, growth factors, and matrix components, they are thought to play critical roles in inflammation, growth, repair, and neoplasia. OBJECTIVE: The goal of this study was to identify the distinct cell populations of the lamina propria of normal colon and colorectal polyps. DESIGN: We studied the expression of alpha-smooth muscle actin (alphaSMA), smooth muscle myosin (SMM), desmin, vimentin, and c-kit by intestinal mesenchymal (stromal) cells in the normal colonic mucosa (n = 5), as well as in hyperplastic polyps (n = 5), sporadic colorectal adenomas (n = 47), and adenomas from patients with familial polyposis (n = 36). RESULTS: In the normal colonic mucosa, the pericryptal stromal cells were alphaSMA+, SMM+, desmin-, and vimentin+, defining them as myofibroblasts. In contrast, cells of the muscularis mucosae were alphaSMA+, SMM+, desmin+, and vimentin-, defining them as smooth muscle cells. alpha-Smooth muscle actin also highlighted direct connections between the muscularis mucosae and the pericryptal myofibroblasts, and vimentin immunostaining showed a network of connections between the alphaSMA+ pericryptal myofibroblasts and the alphaSMA- fibroblasts in the interstitium. In all hyperplastic polyps and adenomatous polyps, the interstitial stromal cells (fibroblasts) now also express alphaSMA and form a syncytium of alphaSMA+ networklike connections throughout the lamina propria. Stromal cells of sporadic adenomas demonstrated the same immunohistochemical staining characteristics displayed by adenomas from patients with familial polyposis and by hyperplastic polyps. Conclusions.-These findings indicate that in normal colon, alphaSMA- fibroblasts are the predominant cell type in the lamina propria. However, the pericryptal (subepithelial) stromal cells are a distinct cell type (alphaSMA+ myofibroblast) that is immunophenotypically different from muscularis mucosae smooth muscle cells and are connected to the interstitial, nonpericryptal fibroblasts with which they exist as a network throughout the lamina propria of the normal colon. Furthermore, in both hyperplastic and neoplastic polyps, there are changes in nonpericryptal fibroblasts from vimentin+, alphaSMA-, and SMM- to vimentin+, alphaSMA+, and SMM+; thus, the interstitial fibroblasts are replaced by myofibroblasts. The factors that cause these changes and the origin of the myofibroblasts need to be determined to clarify the biology of colorectal tumorigenesis.

Adenoma↗
PubMed1984

[Recto-sigmoid cancer and polyps in children. Comments apropos of 2 cases of atypical juvenile polyps].

The writers present a report of 2 observations of colo-rectal carcinoma, on a 19 month old infant with a mixed juvenile and adenomatous polyp situated at the recto-sigmoid junction and treated successfully by segmental colectomy, and on a 10 years old girl presenting a large colloid rectal carcinoma which occurred 6 years after resection of an atypical rectal juvenile polyp. After recalling the rarity and the gravity of colo-rectal carcinoma in childhood, the authors underline the importance of histological investigations in the juvenile polyposis which is usually benign; the possibility of histological aspects on separate polyps and sometimes on the same polyp explains the degeneration of some multiple juvenile polyps (several cases in the literature), or isolated polyp (first case described).

Adenocarcinoma↗
PubMed2003

Inflammatory myoglandular polyp--a rare but distinct type of colorectal polyps.

The aim of this paper was to report another example of a rare type of colorectal polyps, the inflammatory myoglandular polyp, and to reaffirm this type of polyp as a distinct entity. This solitary pedunculated polyp was detected after a single episode of rectal bleeding. It was situated in the sigmoid colon, measured 2.5 cm in greatest diameter, and was composed almost exclusively of smooth muscles and hyperplastic glands. The patient had neither chronic colitis nor diverticula. Clinical presentation, localization, and histology give this type of polyp a unique appearance and justify its designation as a separate entity.

Adult↗
PubMed2003

Hyaluronan and alpha-atrial natriuretic polypeptide in human nasal polyps: contributing factors to oedema formation and polyp growth?

OBJECTIVES: To identify and localize hyaluronan (HYA) and alpha-atrial natriuretic polypeptide (ANP) in human nasal polyps and to measure the HYA concentrations. MATERIAL AND METHODS: Twelve nasal polyps were collected during routine polypectomies and processed histochemically and biochemically to determine the occurrence of HYA. The distribution of ANP was investigated using an immunocytochemical method. RESULTS: HYA was unevenly distributed, being found abundantly in the surface epithelium and basement membrane and around fibres and vessels in the lamina propria. It was also present around seromucinous glands and in the secretion of cysts in the stroma. The HYA concentration was 1,000-fold higher than in serum. ANP was abundant in the apical part of ciliated surface epithelial cells and extracellularly in the basement membrane. In the stroma, ANP was confined to apical acinar cells of the seromucinous glands. CONCLUSIONS: Osmotically active HYA and numerous ANP-immunoreactive cells, active in fluid and/or ion transport functions, are present in human nasal polyps. These substances may well be involved in oedema formation and the successive growth of nasal polyps. The high concentrations of HYA in nasal polyps may be of clinical significance for the future development of a local enzyme treatment for nasal polyposis.

Adult↗
PubMed2006

Advanced colorectal polyps with the molecular and morphological features of serrated polyps and adenomas: concept of a 'fusion' pathway to colorectal cancer.

AIM: To establish and explain the pattern of molecular signatures across colorectal polyps. METHODS AND RESULTS: Thirty-two sessile serrated adenomas (SSA), 10 mixed polyps (MP), 15 traditional serrated adenomas (SA), 49 hyperplastic polyps (HP) and 84 adenomas were assessed for mutation of KRAS and BRAF and aberrant expression of p53. The findings were correlated with loss of expression of O-6-methylguanine DNA methyltransferase (MGMT). KRAS mutation occurred more frequently (26.5%) than BRAF mutation (4.8%) in adenomas (P < 0.001) and particularly in adenomas with villous architecture (50%). Loss of expression of MGMT correlated with KRAS mutation in small tubular adenomas (P < 0.04). BRAF mutation was frequent in HPs (67%) and SSAs (81%), while KRAS mutation was infrequent (4% and 3%, respectively). Of MPs and SAs, 72% had either BRAF or KRAS mutation. Aberrant expression of p53 was uncommon overall, but occurred more frequently in MPs and SAs (12%) than adenomas (1%) (P < 0.04) and there was concordant loss of expression of MGMT. CONCLUSIONS: Molecular alterations that are characteristic of the serrated pathway and adenoma-carcinoma sequence can co-occur in a minority of advanced colorectal polyps that then show morphological features of both pathways. These lesions account for only 2% of colorectal polyps, but may be relatively aggressive.

Adenoma↗
PubMed1985

Epidemiology of polyps in the rectum and sigmoid colon. Histological examination of resected polyps.

In an endoscopic screening study of rectosigmoidal polyps in a defined normal population aged 50-59 years, polyps 5 mm or larger in diameter were removed by diathermic snare resection for histological examination. Histological examination was possible in 50 of 55 polyps removed during colonoscopy from 27 men and 17 women. Of these polyps 41 (82%) were adenomas--12 with moderate dysplasia, 1 with severe dysplasia, and 2 with intramucosal carcinoma. In addition, a small ulcerating carcinoma, Dukes stage A, was found. A greater extent of dysplasia was found in rectosigmoidal adenomas in women, whereas more polyps were found in both distal and proximal parts of the colon among men. The size of adenomas and degree of dysplasia were unrelated to color of the lesions.

Adenoma↗
PubMed1992

Colorectal polyps in autopsy material. Part I. Adenomatous polyps.

In prospective studies specimens of the large bowel were obtained from 733 autopsy cases. After fixing they were examined under illuminated magnifying lens and all polypous lesions were excised for histological analysis and classified according to Correa's criteria (8). Adenomatous polyps were found in 280 cases (38.2%) and their prevalence increased with age in both sexes. Adenomatous polyps, also multiple were found most frequently in the transverse colon, and then ascending colon, sigmoid, descending colon and rectum. The mean number of adenomatous polyps per positive specimen was 2.33 for men and 2.60 for women. In 6.8% their diameter was > or = 10 mm. The prevalence of polyps with severe degree of dysplasia (III degree) increased from proximal to distal segments of the colon in both sexes and their prevalence is significantly higher in the ascending colon in women. In the whole series there were 6 adenocarcinomas of 5-18 mm in size, all in women over 80 years of age. The results of the present study were compared with the data concerning other populations of the world. In the light of a repeatedly confirmed a generally accepted relationship between adenoma and adenocarcinoma of the large intestine the results of our study seem to underestimate the prevalence of colon adenocarcinoma in the population of Cracow and Cracow district.

Adenocarcinoma↗
PubMedDate not supplied

Nonrandom chromosomal abnormalities in lymphocyte cultures of individuals with colorectal polyps and of asymptomatic relatives of patients with colorectal cancer or polyps.

We studied chromosomal alterations in the peripheral blood lymphocytes of 10 individuals with colorectal polyps and 10 asymptomatic first-degree relatives of patients with colon cancer or colorectal polyps. The analysis was performed on T-lymphocytes using short term blood cultures and on B-lymphocytes by establishing lymphoblastoid cell lines by Epstein-Barr virus transformation. Chromosomal changes were not common in T- and B-lymphocytes. Chromosomes 1 and 5 were most frequently involved in numerical or structural changes in the patients with polyps as well as in the asymptomatic relatives. These alterations were observed in either the T-lymphocytes or the B-lymphocytes but rarely in both, thus accentuating the importance of studying both the cultures concurrently. Chromosome 5, which is known to play an important role in the development of adenomatous polyps, was found to be involved in 6 (60%) of 10 patients with polyps and 4 (40%) of 10 asymptomatic relatives. These findings show that lymphocytic chromosomal analysis can aid in identifying individuals who are genetically susceptible and are at a higher risk of developing colorectal cancer. Because lymphocytic chromosomal analysis is relatively simple and inexpensive, we expect that it will be very useful in screening asymptomatic individuals who are at a higher risk due to inherited or environmental factors.

Adult↗
PubMed1987

Gastric and duodenal polyps in familial adenomatous polyposis: a prospective study of the nature and prevalence of upper gastrointestinal polyps.

One hundred patients with familial adenomatous polyposis have prospectively undergone gastroduodenoscopy to identify and characterise polyps found. Forty six patients had polyps in the stomach or duodenum. Thirty five patients had adenomas (33 in duodenum, two in stomach) and 26 patients had fundic gland polyps. Some of these patients had polyps in the stomach and the duodenum. Adenomas in the duodenum were present in 33% of patients studied with Gardner's syndrome variant (p = 0.04). Adenomas were also more common in older patients. As adenomas may be a precursor of adenocarcinoma, routine surveillance of the stomach and duodenum with gastroduodenoscopy is recommended in patients affected with familial adenomatous polyposis.

Adenomatous Polyposis Coli↗
PubMed1996

Prolapsing gastric polyp, an unusual cause of gastric outlet obstruction: a review of the pathology and management of gastric polyps.

Gastric polyps are rare and largely asymptomatic, but attract importance because of their strong potential to progress to carcinoma. Rarely, pedunculated polyps arising in the antrum may prolapse through the pylorus, causing intermittent gastric outlet obstruction. We describe here our experience of four cases collected over a ten-year period, each presenting dissimilarly with this phenomenon. We review the literature referring to the pathogenesis of gastric polyps and their association with malignancy and other disorders. We proceed to discuss the efficacy of barium studies versus gastroscopy in detecting these lesions, the relative roles and merits of endoscopic polypectomy and surgery, and the importance of prolonged follow-up of patients harbouring gastric polyps.

Aged↗
PubMed1993

Randomized comparison of surveillance intervals after colonoscopic removal of newly diagnosed adenomatous polyps. The National Polyp Study Workgroup.

BACKGROUND: The identification and removal of adenomatous polyps and post-polypectomy surveillance are considered to be important for the control of colorectal cancer. In current practice, the intervals between colonoscopies after polypectomy are variable, often a year long, and not based on data from randomized clinical trials. We sought to determine whether follow-up colonoscopy at three years would detect important colonic lesions as well as follow-up colonoscopy at both one and three years. METHODS: Patients were eligible if they had one or more adenomas, no previous polypectomy, and a complete colonoscopy and all their polyps had been removed. They were randomly assigned to have follow-up colonoscopy at one and three years or at three years only. The two study end points were the detection of any adenoma, and the detection of adenomas with advanced pathological features (defined as those > 1 cm in diameter and those with high-grade dysplasia or invasive cancer). RESULTS: Of 2632 eligible patients, 1418 were randomly assigned to the two follow-up groups, 699 to the two-examination group and 719 to the one-examination group. The percentage of patients with adenomas in the group examined at one and three years was 41.7 percent, as compared with 32.0 percent in the group examined at three years (P = 0.006). The percentage of patients with adenomas with advanced pathological features was the same in both groups (3.3 percent). CONCLUSIONS: Colonoscopy performed three years after colonoscopic removal of adenomatous polyps detects important colonic lesions as effectively as follow-up colonoscopy after both one and three years. An interval of at least three years is recommended before follow-up colonoscopy after both one and three years. An interval of at least three years is recommended before follow-up examination after colonoscopic removal of newly diagnosed adenomatous polyps. Adoption of this recommendation nationally should reduce the cost of post-polypectomy surveillance and screening.

Adenoma↗
PubMed1996

Risk of colorectal cancer in the families of patients with adenomatous polyps. National Polyp Study Workgroup.

BACKGROUND: The adenoma-adenocarcinoma sequence in colorectal cancer suggests an increased risk of colorectal cancer in the families of patients with adenomatous polyps. METHODS: A random sample of participants in the National Polyp Study who had newly diagnosed adenomatous polyps were interviewed for information on the history of colorectal cancer in their parents and siblings. The risk of colorectal cancer in family members was analyzed according to the characteristics of the patients with adenomas and in comparison with a sample of patients' spouses, who served as controls. RESULTS: Among the patients with adenomas, 1199 provided information on whether they had a family history of colorectal cancer. After the exclusion of families for which information was incomplete and of 48 patients who had been referred for colonoscopy solely because they had a family history of colorectal cancer, there were 1031 patients with adenomas, 1865 parents, 2381 siblings, and 1411 spouse controls. The relative risk of colorectal cancer, adjusted for the year of birth and sex, was 1.78 for the parents and siblings of the patients with adenomas as compared with the spouse controls (95 percent confidence interval, 1.18 to 2.67). The relative risk for siblings of patients in whom adenomas were diagnosed before 60 years of age was 2.59 (95 percent confidence interval, 1.46 to 4.58) as compared with the siblings of patients who were 60 or older at the time of diagnosis and after adjustment for the sibling's year of birth and sex and a parental history of colorectal cancer. The risk increased with decreasing age at the time of the diagnosis of adenoma (P for trend < 0.001). The relative risk for the siblings of patients who had a parent with colorectal cancer, as compared with those who had no parent with cancer, was 3.25 (95 percent confidence interval, 1.92 to 5.52), after adjustment for the sibling's year of birth and sex and the patient's age at diagnosis. CONCLUSIONS: Siblings and parents of patients with adenomatous polyps are at increased risk for colorectal cancer, particularly when the adenoma is diagnosed before the age of 60 or--in the case of siblings--when a parent has had colorectal cancer.

Adenomatous Polyps↗