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PubMed1982

Intestinal metaplasia of the stomach as a precancerous stage.

Intestinal metaplasia is defined as the appearance of intestinal epithelium in the stomach. Intestinal metaplasia is frequently found in populations with a high incidence of gastric cancer. Macroscopic demonstration of sucrase and trehalase with Tes-tape in many resected stomachs yielded new information for understanding the nature of intestinal metaplasia. Intestinal metaplasia can be classified into two types, complete and incomplete. The former is associated with the presence of sucrase, trehalase, leucine aminopeptidase, alkaline phosphatase, goblet cells and Paneth cells, and the latter with that of sucrase, leucine aminopeptidase and goblet cells, but not trehalase or Paneth cells. Goblet cells in the complete type of intestinal metaplasia contain sialomucin, as does the small intestine, while those in the incomplete type contain sulphomucin and sialomucin, as does the large intestine. Well-differentiated adenocarcinoma is closely related to intestinal metaplasia, especially the incomplete type. Atypical epithelium of intestinal metaplasia has been proposed as a more proximate stage of gastric cancer. Intestinal metaplasia can be diagnosed by staining with dye under endoscopic observation. A reduced level of pepsinogen I in the blood reflects the presence of severe intestinal metaplasia, which is understood to be a sign of high risk of gastric cancer. Intestinal metaplasia is supposed to be produced by components of food. Mutagens/carcinogens such as N-methyl-N'-nitro-soguanidine and N-propyl-N'-nitro-N-nitrosoguanidine can produce intestinal metaplasia in the glandular stomach of rats and gastric cancers. The formation of intestinal metaplasia precedes the appearance of adenocarcinoma in the glandular stomach. Intestinal metaplasia, which is a kind of host reaction to environmental agents, may result either from genetic change - change in DNA structure - or from epigenetic change - change in the differentiation mechanism. Preventive measures could be developed to suppress the development of intestinal metaplasia and to suppress the process of conversion of metaplastic cells to cancer cells.

Cell Differentiation↗
PubMed2005

Expression of growth differentiation factor-5 and bone morphogenic protein-7 in intraocular osseous metaplasia.

BACKGROUND/AIMS: Intraocular bone is seen in a wide spectrum of ocular disorders. The pathogenetic mechanisms of bone formation in the eye are unclear. Growth differentiation factor-5 (GDF-5), bone morphogenic protein-7 (BMP-7), and transforming growth factor beta-1 (TGF beta1) are multifunctional cytokines that have important roles in bone formation. Immunohistochemistry was used to localise GDF-5, BMP-7, and TGF beta1 in the human eye to determine their role in intraocular bone formation. METHODS: Paraffin embedded sections from human eyes included fetal eyes (n = 5), normal adult eyes (n = 4), eyes with osseous metaplasia (n = 8), and eyes with focal fibrous metaplasia of the retinal pigment epithelium (RPE) without osseous metaplasia (n = 2). Immunohistochemistry was performed using indirect immunofluorescence with antibodies to GDF-5, BMP-7, and TGF beta1. The staining intensity was evaluated semiquantitatively in the RPE, retina, ciliary epithelium, and cornea; and analysed statistically. RESULTS: When compared with normal adult eyes, which showed no RPE immunoreactivity, the RPE metaplasia surrounding areas of osseous metaplasia showed mild GDF-5 and moderate BMP-7 (p = 0.004) intracytoplasmic immunoreactivity. In contrast, trace GDF-5 and mild BMP-7 staining was seen in zones of RPE fibrous metaplasia in areas not associated with osseous metaplasia. Mild intracytoplasmic TGF beta1 expression was seen in the RPE metaplasia surrounding the bone when compared with adult eyes. Both fetal and adult eyes showed trace to mild GDF-5 and BMP-7 labelling of the non-pigmented ciliary epithelium which was increased in the eyes with osseous metaplasia. In eyes with osseous metaplasia, a significant decrease in GDF-5 and BMP-7 labelling was noted in fetal keratocytes (p = 0.0159 for both antibodies) when compared to adult eyes. Also, a significant decrease in BMP-7 labelling was seen in keratocytes in eyes with osseous metaplasia (p = 0.0162). CONCLUSIONS: The increase in GDF-5, BMP-7, and TGF beta1 immunoreactivity in zones of RPE metaplasia in eyes with osseous metaplasia suggests that these proteins have an important role in intraocular ectopic bone formation.

Adult↗
PubMed1981

Distribution and ultrastructural characteristics of dark cells in squamous metaplasias of the respiratory tract epithelium.

Dark epithelial basal cells were found in both carcinogen-induced and non-carcinogen-induced squamous metaplasias of the tracheal epithelium. Formaldehyde-induced squamous metaplasias exhibited 4% dark cells in the basal layer. Metaplasias induced by vitamin A deficiency and those induced by dimethylbenz(alpha)anthracene (DMBA) without atypia showed 18--20% basal dark cells. DMBA-induced metaplasias with moderate to severe atypia exhibited 50% basal dark cells. The labeling index of basal cells in metaplastic epithelia, regardless of the inducing agent, was 16--18%, ie, the same as that of the normal esophageal stratified squamous epithelium. The percentage of labeled dark basal cells per total dark cell population was approximately 19% in the non-carcinogen-induced metaplasias and in the DMBA-induced metaplasias without atypia. In the atypical metaplasias induced by DMA this percentage increased to 26. On the basis of ultrastructural observations, five types of dark epithelial cells could be distinguished in the metaplastic epithelia: Type I (ovoid or fusiform dark cell with abundant cytoplasmic filaments, desmosomes, and free ribosomes--dark keratinocyte type); Type II (ovoid or spherical small cell with scant cytoplasm with few organelles--basal respiratory type); Type III (irregular or ovoid, few cytoplasmic filaments and organelles and desmosomes, extremely abundant free ribosomes--dedifferentiated type); Type IV (fusiform or ovoid, large mitochondria, prominent ergastoplasm, secretion droplets--mucous cell type); and type V (irregular shape, organelle remnants, vacuoles, pyknotic nuclei--involutional-cell type). Type I was the predominant cell type in formaldehyde-induced metaplasias and was also commonly seen in DMBA-induced metaplasias without atypia. Type II predominated in metaplasias induced by vitamin A deficiency. Type III was seen in DMBA-induced metaplasias and was the predominant cell type in the atypical epithelial alterations. Type IV cells occurred only in the latter, and Type V cells were occasionally seen in formaldehyde- as well as in DMBA-induced atypical metaplasias. Each type of squamous metaplasia could thus be recognized by a determined numerical distribution of dark cells in the basal layer and a specific pattern of distribution of the ultrastructurally defined dark cell categories.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1996

The prevalence and clinical characteristics of short segments of specialized intestinal metaplasia in the distal esophagus on routine endoscopy.

OBJECTIVE: To prospectively determine the prevalence and clinical characteristics of short segments of specialized intestinal metaplasia in the distal esophagus. Short segment is defined as extending less than 2 cm proximal to the esophagogastric junction. This has been referred to by some investigators as "short segment Barrett's esophagus." METHODS: One hundred and seventy two patients undergoing elective esophagogastroduodenoscopy were consecutively enrolled. Patients with known Barrett's esophagus were excluded. All study patients completed a symptom questionnaire. At endoscopy, the presence of esophagitis and locations of the diaphragmatic hiatus, esophagogastric junction, and the squamocolumnar junction were recorded. Biopsy specimens were obtained at the squamocolumnar junction to identify specialized intestinal metaplasia and 2 cm above the squamocolumnar junction to evaluate for histological esophagitis. RESULTS: Two patients (1.2%) had at least 2 cm of columnar-lined esophagus. Of the 170 patients without 2 cm of columnar-lined esophagus, 16 (9.4%) patients had short segments of specialized intestinal metaplasia. Twelve (7.0%) of these patients had specialized intestinal metaplasia limited to the esophagogastric junction. All patients with specialized intestinal metaplasia were Caucasian, and there was a slight male predominance. Patients without specialized intestinal metaplasia (n = 154, 90.6%) did not differ statistically with respect to age, gender, use of acid-suppressing drugs, alcohol, or smoking history. Pyrosis and regurgitation were significantly more common in patients with specialized intestinal metaplasia involving the distal 2 cm of the esophagus or the esophagogastric junction. Cough was more common in the group with specialized intestinal metaplasia limited to the esophagogastric junction. The groups were similar in frequency of dysphagia, globus sensation, nocturnal pyrosis, eructation, early satiety, nausea, and abdominal pain. CONCLUSIONS: Specialized intestinal metaplasia less than 2 cm proximal to the esophagogastric junction is common in Caucasian patients undergoing routine esophagogastroduodenoscopy. Pyrosis and regurgitation are significantly more common in patients with short segments of specialized intestinal metaplasia, whether involving the distal 2 cm of the esophagus or the esophagogastric junction alone. Alcohol and tobacco use are no more common in patients with specialized intestinal metaplasia than in those without metaplasia. The presence of specialized intestinal metaplasia did not correlate with either endoscopic or histological esophagitis.

Age Distribution↗
PubMedDate not supplied

Intestinal metaplasia of the gastric cardia: a study from Turkey.

BACKGROUND/AIMS: We aimed to investigate the prevalence of intestinal metaplasia in the cardia of a patient group with high incidence of Helicobacter pylori infection presenting for elective upper endoscopy. We also re-evaluated the relation between intestinal metaplasia in the cardia and gastroesophageal reflux disease, smoking, alcohol history, H. pylori infection, Barrett's esophagus and intestinal metaplasia elsewhere in the stomach. METHODOLOGY: Sixty patients presenting for elective upper endoscopy were included in this study. Prior to undergoing endoscopy each patient was questioned with regard to the clinical indication and symptoms including heartburn, regurgitation, and dysphagia. In addition, a smoking and alcohol history were recorded. Endoscopic biopsies: 1) one from the midantrum on the lesser curvature, 2) one from the incisura angularis, 3) one from the mid-corpus on the lesser curvature, 4) one from the columnar side of the squamocolumnar junction, 5) one from the squamous side of the squamocolumnar junction, 6) one from 2 cm distal to the esophagogastric junction, 7) one from across the squamocolumnar junction. Slides were stained using a combination of hematoxylin-eosin with Alcian blue at pH 2.5 for intestinal metaplasia. Each specimen was examined for the presence of H. pylori. RESULTS: The prevalence of H. pylori infection was 63%. Prevalence of the H. pylori infection was significantly lower in the patients with intestinal metaplasia of the cardia than in the patients without intestinal metaplasia of the cardia (P = 0.025). There was a positive correlation between the age of the patients and having intestinal metaplasia of the cardia (r = 0.286, P = 0.008). There was no relationship between intestinal metaplasia of the cardia and pyrozis, regurgitation, dysphagia, history of alcohol and smoking esophagitis determined by endoscopy or histopathology, sex, intestinal metaplasia elsewhere in the stomach (P > 0.05). CONCLUSIONS: The incidence of the intestinal metaplasia of the gastric cardia in Turkey is less than that of western countries. Intestinal metaplasia of the gastric cardia negatively correlates with H. pylori infection. And there was no relationship between gastric cardia intestinal metaplasia and reflux disease. Further investigations are needed for determining the premalign lesion and etiologic factors for cancer of the gastric cardia.

Adult↗
PubMed1987

Barrett's metaplasia and adenocarcinoma of the esophagus in scleroderma.

Gastroesophageal reflux is well documented in scleroderma, but the complications of Barrett's metaplasia and adenocarcinoma are not well described. The records of 75 patients with scleroderma seen over a four-year period at the Hospital of the University of Pennsylvania were retrospectively reviewed to determine the prevalence of Barrett's metaplasia and adenocarcinoma of the esophagus and to identify clinical, manometric, laboratory, or radiographic criteria that might predict the presence of these lesions. Twenty-four of these patients underwent endoscopy. In this group, the prevalence of Barrett's metaplasia was 37 percent (nine patients) and adenocarcinoma was also present in two of these patients. The patients with and without Barrett's metaplasia were similar in age (range, 22 to 64 compared with 28 to 79, respectively), sex (six of nine compared with 12 of 15 female, respectively), frequency of esophageal motility disorders, presence of proximal skin involvement, digital ulceration, and pulmonary involvement as measured by diffusion capacity. Barrett's metaplasia was diagnosed on the basis of double-contrast esophagographic results in only one of eight patients with Barrett's metaplasia so-studied. Patients with Barrett's metaplasia tended to have longer duration of heartburn (90 +/- 40 months compared with 11 +/- 35 months) and dysphagia (39 +/- 22 months compared with 7 +/- 3 months). Patients with Barrett's metaplasia also tended to have greater impairment of lower esophageal sphincter pressure either at end-expiration (4.0 +/- 2.1 compared with 6.1 +/- 1.8 mm Hg) or mid-respiration (13.0 +/- 3.0 compared with 16.9 +/- 2.5 mm Hg). Using chi-square analysis, however, none of these differences reached statistical significance. Discrimination did occur on the basis of the presence of the CREST (calcinosis, Raynaud's phenomenon, esophageal manifestations of scleroderma, sclerodactyly, and telangiectasis) variant (55 percent compared with 7 percent, p less than 0.01), a duration of dysphagia of more than five months (p less than 0.03), and mid-respiratory lower esophageal sphincter pressure of less than 10 mm Hg (p less than 0.05). It is suggested that: Barrett's metaplasia of the esophagus occurs in one third of patients with scleroderma; clinical, manometric, laboratory, and radiographic features are poor predictors of the presence of Barrett's metaplasia; patients with CREST syndrome, prolonged dysphagia, or a very low lower esophageal sphincter pressure may have an increased risk for the development of metaplasia; patients with scleroderma and Barrett's metaplasia have an increased risk of complications such as stricture or adenocarcinoma.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenocarcinoma↗
PubMed2006

Divergent pathway of intestinal metaplasia and cystitis glandularis of the urinary bladder.

Intestinal metaplasia has been proposed to be a precursor lesion of adenocarcinoma in the urinary bladder. CDX2 is a transcription factor that is encoded by a homeotype gene that plays an essential role in the differentiation and proliferation of intestinal epithelial cells. Hepatocyte-specific antigen (Hep) has also been shown to be a useful marker of intestinal metaplasia. Tissues from 46 patients, including 22 cases of intestinal metaplasia of the urinary bladder, 11 cases of typical cystitis glandularis, and 13 cases containing both lesions, were selected and immunohistochemical stains for CDX2, Hep, cytokeratin 20 (CK20), and cytokeratin 7 (CK7) were performed. Nuclear staining for CDX2 was observed in 29 of 35 (83%) cases of intestinal metaplasia of the urinary bladder. In contrast, nuclear staining for CDX2 was not observed in any case of typical cystitis glandularis; however, seven of 24 (29%) cases showed aberrant cytoplasmic expression in a mean of 37% of cells. CK20 was expressed in 28 of 35 (80%) cases of intestinal metaplasia, but was observed in only one of 24 (4%) cases of cystitis glandularis in 15% of cells. CK7 was expressed in only six of 35 (17%) cases of intestinal metaplasia, whereas expression of CK7 was observed in all cases (100%) of typical cystitis glandularis with a mean percentage of positively staining cells of 63%. The mean percentages of positively staining cells in intestinal metaplasia with CDX2, CK20, and CK7 were 55, 49, and 53%, respectively. All examples of both intestinal metaplasia and typical cystitis glandularis were uniformly negative for Hep. In the urinary bladder, intestinal metaplasia and typical cystitis glandularis have sharply contrasting immunoprofiles. Additionally, the absence of Hep staining in intestinal metaplasia of the urinary bladder, despite its morphologic resemblance to normal colonic mucosa and intestinal metaplasia in other organs, may signify the presence of unique metaplastic pathways in the urinary bladder.

Autoantigens↗
PubMed2000

The location and frequency of intestinal metaplasia at the esophagogastric junction in 223 consecutive autopsies: implications for patient treatment and preventive strategies in Barrett's esophagus.

The frequency of intestinal metaplasia at the esophagogastric junction is as high as 36% in endoscopy studies; the majority of cases (approximately 67%) occur in short segments of esophageal columnar mucosa. The validity of these studies has been questioned, however, because of heterogenous underlying diseases prompting endoscopy. To determine the frequency and origin of intestinal metaplasia at the esophagogastric junction, we histologically evaluated the entire esophagogastric junction for the presence of intestinal metaplasia using Alcian blue/periodic acid-Schiff mucin stains in 223 consecutive autopsies. Precise localization of the Z line in relation to the esophagogastric junction and tongues of esophageal columnar-appearing mucosa were noted in each case. Mean patient age was 47 years; 69% of patients were male, and 63% were white. Twenty five of 223 cases (11%) had intestinal metaplasia at the esophagogastric junction. Only 2 of 25 cases (8%) had intestinal metaplasia in the esophagus; the remaining 23 cases (92%) had intestinal metaplasia in the gastric cardia. Male gender, advanced age, white ethnic origin, and short tongues of esophageal columnar mucosa were not associated with gastric cardia intestinal metaplasia. An association of distal gastric intestinal metaplasia (P < .01) and chronic gastritis (P < .01) with gastric cardia intestinal metaplasia suggests a role for Helicobacter pylori infection in this process. The frequency of intestinal metaplasia at the esophagogastric junction in an unselected autopsy population is low (11%) even after exhaustive histologic evaluation using Alcian blue mucin stains. Furthermore, intestinal metaplasia is confined to the gastric cardia in more than 90% of cases with no association to male gender, white ethnic origin, advanced age, or the presence of short segments of esophageal columnar-appearing mucosa at endoscopy. These results demonstrate that caution is warranted when applying the findings of endoscopy studies to the development of preventive and screening strategies aimed at identifying Barrett's esophagus in an asymptomatic general population.

Adolescent↗
PubMed1998

The impact of an antireflux procedure on intestinal metaplasia of the cardia.

OBJECTIVE: The aim of this study was to determine whether antireflux surgery is more effective in producing loss of intestinal metaplasia located only at the gastroesophageal junction than it has been in patients with intestinal metaplasia extending up into the distal esophagus. SUMMARY BACKGROUND DATA: Biopsies of a normal appearing gastroesophageal junction will demonstrate cardiac mucosa containing goblet cells--the hallmark of intestinal metaplasia--in 10% to 15% of patients who are evaluated for symptoms of gastroesophageal reflux. The incidence of adenocarcinoma of the esophagus and cardia is rising faster than any other cancer in America, and most of these cancers are found adjacent to areas of intestinal metaplasia. Antireflux surgery in patients with Barrett's esophagus may provide protection from progression to dysplasia and cancer; however, it does not reliably cause regression of the intestinal metaplasia. Less is known about the potential for intestinal metaplasia limited to the cardia (CIM) to regress. METHODS: Sixty patients with intestinal metaplasia of the esophagus or cardia had antireflux surgery. Patients in the intestinal (CIM) group (n = 15) had no endoscopically visible segment of columnar epithelium. Patients in the Barrett's group (n = 45) had columnar epithelium visible within the esophagus. Median follow-up was 25 months in each group. RESULTS: Postoperative biopsies showed complete loss of intestinal metaplasia in 73% of the patients with CIM compared with 4.4% of the patients with Barrett's. Low-grade dysplasia, present in 10 patients preoperatively, regressed in 7 patients (70%). No patient progressed to high-grade dysplasia or cancer. CONCLUSIONS: Loss of intestinal metaplasia after antireflux surgery is rare in patients with Barrett's, but occurred in most patients with CIM. This suggests that cardiac epithelium is dynamic and that microscopic areas of intestinal metaplasia are able to regress much more frequently than longer, visible segments of intestinal metaplasia.

Adult↗
PubMed2001

A novel method for detecting single glandular intestinal metaplasia in the mucosal surface of the fixed stomach using methylene blue.

A close association between intestinal metaplasia of the stomach and the well-differentiated type of gastric cancer is well recognized. The etiological relationship and how intestinal metaplasia contributes to gastric carcinogenesis are, however, still unclear. In order to answer this question, precise mapping and identification of the smallest lesion of intestinal metaplasia are desired. Establishment of an accurate and easy method for detecting intestinal metaplasia was the goal of this study. Surgical specimens of stomachs resected for gastric cancer were used. The specimens were stained with methylene blue, an oxidation-reduction marker, in whole mount, after fixation with 4% paraformaldehyde in 0.1 M phosphate buffer (pH 7.4), and observed under a stereo-microscope. Normal gastric mucosa was stained blue, whereas intestinal metaplasia mucosa was not stained and had white or sky-blue island-like features. Intestinal metaplasia of complete type was unstained and showed white island-like features, while intestinal metaplasia of incomplete type showed sky-blue staining. With this method, we were able to detect even intestinal metaplasia composed of a single gland, when the intestinal metaplasia was of complete type. When stomach samples were stained in the presence of diphenyleneiodonium chloride (DPI), an inhibitor of nicotineamide adenine dinucleotide phosphate reduced form (NADPH) reductase, all the samples were homogeneously stained blue. Loss of the color of methylene blue was caused by the reductase activity of NADPH reductase, which is strongly and specifically expressed in intestinal metaplasia. A novel method for detecting intestinal metaplasia, even a single gland, was established.

Coloring Agents↗
PubMed2007

Is intestinal metaplasia a necessary precursor lesion for adenocarcinomas of the distal esophagus, gastroesophageal junction and gastric cardia?

Adenocarcinoma of the distal esophagus and gastroesophageal junction are believed to arise in Barrett's esophagus with intestinal metaplasia. Whether adenocarcinoma can arise in columnar lined esophagus without intestinal metaplasia is in doubt. Whether adenocarcinoma of the gastric cardia arises in intestinal metaplasia of the gastric cardia is also in doubt. We aim to evaluate the relationship of size and stage of adenocarcinoma of the distal esophagus, gastroesophageal junction and gastric cardia to intestinal metaplasia and other types of columnar epithelium. Seventy-four patients who had esophagogastrectomy for adenocarcinomas in this region were examined histologically to assess the frequency of residual intestinal metaplasia in the surrounding epithelium. Tumors without residual intestinal metaplasia were evaluated for the presence of other columnar epithelia and correlated with tumor size and stage. Cardiac mucosa was present around all tumors. Residual intestinal metaplasia was present in 48 (65%) tumors, including 33/38 (87%) distal esophageal, 10/25 (45%) junctional and 5/11 (45%) gastric cardia tumors. The prevalence of intestinal metaplasia was 100% in all tumors that were less than 1 cm in maximum diameter and all intramucosal tumors. The prevalence of residual intestinal metaplasia decreased with increasing tumor size and stage. These data strongly support the contention that adenocarcinomas of this region, including those in the gastric cardia, arise in intestinal metaplastic epithelium. The absence of residual intestinal metaplasia in larger tumors is the result of tumor overgrowing the intestinal metaplasia from which it arose.

Adenocarcinoma↗
PubMed1999

Characteristics of intestinal metaplasia in the gastric cardia.

OBJECTIVE: Intestinal metaplasia of the gastroesophageal junction is frequently grouped together with Barrett's esophagus. The area of the gastroesophageal junction is comprised of the distal esophagus and the gastric cardia. The aim of the present study was to assess whether intestinal metaplasia in the distal esophagus and gastric cardia represent two different entities with a different set of risk factors. METHODS: Patients presenting for elective upper endoscopy were enrolled into a prospective study. The presence of gastritis and intestinal metaplasia was evaluated in gastric biopsies taken from the antrum, corpus, and cardia. Barrett's esophagus was defined by the presence of any length of columnar mucosa above the gastroesophageal junction. RESULTS: Of 302 patients, 50 patients had intestinal metaplasia of the gastric cardia, 73 Barrett's esophagus, and 116 erosive esophagitis. Men were more prone than women to develop Barrett's esophagus or erosive esophagitis. Both conditions were also more common among whites than nonwhites. Smoking was particularly common among patients with Barrett's esophagus. Patients with cardiac intestinal metaplasia did not share these demographic characteristics. The prevalence of daily reflux symptoms, erosive esophagitis, and Barrett's esophagus was similar among patients both with and without cardiac intestinal metaplasia. However, atrophy and intestinal metaplasia of the gastric antrum and corpus were found more frequently among patients with than without cardiac intestinal metaplasia. CONCLUSIONS: Intestinal metaplasia of the gastric cardia is different from Barrett's esophagus. Although cardiac intestinal metaplasia is closely associated with signs of gastritis in other parts of the stomach, gastroesophageal reflux disease does not seem to be a risk factor. A diagnosis of Barrett's esophagus should not be made based on the presence of intestinal metaplasia within the cardiac portion of the gastroesophageal junction.

Barrett Esophagus↗
PubMed2000

Intestinal and pancreatic metaplasia at the esophagogastric junction in patients without Barrett's esophagus.

OBJECTIVES: A distinctive type of columnar epithelium with intestinal metaplasia is considered diagnostic for Barrett's esophagus. The neoplastic potential of pancreatic metaplasia at the esophagogastric junction is unknown. The aims of the present study were: 1) to characterize both forms of metaplasia at the esophagogastric junction, and to estimate their prevalence; 2) to investigate c-erbB-2 expression and K-ras mutations in pancreatic metaplasia; and 3) to study the relationship between metaplasia, inflammatory changes in the cardiac mucosa, and presence of H. pylori. METHODS: A total of 76 esophagogastrectomy specimens of patients with a normally located squamocolumnar junction, were investigated immunohistochemically. K-ras mutations were evaluated using PCR. RESULTS: Intestinal metaplasia in the cardia was found in 12% of patients: six complete-type, and three incomplete-type. Pancreatic metaplasia was demonstrated in 14% of patients, and neither c-erbB-2 expression nor K-ras mutations were found. Intestinal and pancreatic metaplasia were associated with mucosal inflammation. In contrast to generalized gastritis, isolated "carditis" was not associated with H. pylori infection. CONCLUSIONS: When intestinal metaplasia occurs in a biopsy from the esophagogastric junction, it is not necessarily a marker for Barrett's esophagus. No indication was found that pancreatic metaplasia has neoplastic potential. Both forms of metaplasia reflect mucosal inflammation. Carditis may be a distinct inflammatory condition of the gastric mucosa that is not related to H. pylori infection.

Adenocarcinoma↗
PubMed2002

Small adenocarcinomas of the esophagogastric junction: association with intestinal metaplasia and dysplasia.

OBJECTIVES: Intestinal metaplasia in Barrett's esophagus predisposes to esophageal adenocarcinoma. Intestinal metaplasia of the cardia is a common finding in persons without cancer. Many adenocarcinomas of the esophagogastric junction are large enough to obliterate any underlying intestinal metaplasia. To estimate how often adenocarcinoma of the esophagogastric junction arises in intestinal metaplasia, we studied small adenocarcinomas of the esophagogastric junction. METHODS: Resection patients had adenocarcinomas 2 cm or smaller, within 2 cm of the esophagogastric junction. Age- and sex-matched controls had resection for squamous carcinoma. Saved and new histological slides from the esophagogastric junction were examined, with additional stains. RESULTS: Intestinal metaplasia was found in 86% (19/22) of adenocarcinoma cases, versus 32% (7/22) of controls (p < 0.001). Intestinal metaplasia with high or low grade dysplasia was associated with 64% (14/22) of adenocarcinomas and with 5% (1/22) of controls (p < 0.001). Excluding four cases with long and three with short Barrett's esophagus, 80% (12/15) of adenocarcinomas had associated intestinal metaplasia, 53% (8/15) with dysplasia. Most adenocarcinoma cases had the incomplete type of intestinal metaplasia with a Barrett type cytokeratin 7/20 staining pattern. Helicobacter pylori were seen in one adenocarcinoma and five control cases. CONCLUSIONS: Most adenocarcinomas of the esophagogastic junction arise in the background of intestinal metaplasia, sometimes in an endoscopically visible Barrett's esophagus, more often in small areas of intestinal metaplasia of the cardia. In cases of adenocarcinoma, the intestinal metaplasia resembled that found in Barrett's esophagus, and was not associated with H. pylori.

Adenocarcinoma↗
PubMed2001

Gastric intestinal metaplasia: subtypes and natural history.

BACKGROUND: It has been suggested that the subtyping of intestinal metaplasia in the stomach is useful in stratifying patients with regard to risk of developing gastric cancer. AIM: To determine whether subtyping intestinal metaplasia provided useful information regarding the natural history of intestinal metaplasia. METHODS: The study used large cup gastric biopsy specimens from predetermined locations (gastric mapping). Follow up biopsies were obtained at one, two, and/or nine years. Biopsies with intestinal metaplasia were stained with high iron diamine/Alcian blue (HID/AB) to determine whether they expressed neutral mucins, sialomucins, or sulphomucins. RESULTS: Seventy nine patients with intestinal metaplasia were studied and characterised with regard to the most advanced subtype of intestinal metaplasia. The most severe type of intestinal metaplasia was type II in 33 patients and type III in 34 patients. Helicobacter pylori was cured in 67 patients. Follow up showed that changes in type of metaplasia (apparent regression or progression) occurred in both directions and were independent of H pylori status. For example, biopsy sites with "loss" of metaplasia at a follow up visit might have it "reappear" at a subsequent visit. During follow up, no patient developed gastric dysplasia or died from gastric cancer. CONCLUSION: HID subtyping did not provide useful information to the clinician or the pathologist. The data are consistent with the notion that the pattern, extent, and severity of atrophy with/without intestinal metaplasia is a far more important predictor of increased cancer risk than intestinal metaplasia subtype.

Adult↗
PubMed1994

Randomized placebo-controlled trial of isotretinoin in chemoprevention of bronchial squamous metaplasia.

PURPOSE: Retinoids have proven chemopreventive efficacy in both preclinical and clinical studies. This trial was designed to confirm the finding of an earlier uncontrolled trial that the synthetic retinoid etretinate had major activity in reversing squamous metaplasia found in the bronchial epithelium of chronic smokers. PATIENTS AND METHODS: We prospectively evaluated 152 smokers with bronchoscopy and obtained biopsies from six sites. Subjects with dysplasia and/or a metaplasia index of greater than 15% were randomly assigned to receive either 1 mg/kg isotretinoin or placebo daily for 6 months. Of 86 subjects randomized (41 isotretinoin, 45 placebo), 69 were reevaluated at the completion of treatment. RESULTS: In the group as a whole, the metaplasia index decreased over time from a mean +/- SE of 35.8% +/- 2.7% at baseline to 28.1% +/- 3.3% at the completion of treatment (P = .01) by repeated measures analysis of variance [ANOVA]); a reduction in the metaplasia index (> 8%) was noted in both isotretinoin and placebo groups (19 of 35 [54.3%] and 20 of 34 [58.8%], respectively). Complete reversal of squamous metaplasia was noted in nine subjects from each group. However, the magnitudes of the mean metaplasia index changes did not differ significantly in the two treatment groups. In both groups, smoking cessation resulted in significant declines in the extent of squamous metaplasia, whereas no significant change in metaplasia index was found among those who continued to smoke. CONCLUSION: Squamous metaplasia was frequently observed in bronchial biopsy samples from chronic smokers. From this study, we conclude that isotretinoin has no effect on squamous metaplasia, a potential intermediate end point of bronchial carcinogenesis. Although determining the exact role of isotretinoin in lung cancer prevention requires further study, the finding that there was a significant decrease in squamous metaplasia in the placebo group emphasizes the critical importance of a placebo-controlled study design in chemoprevention trials using intermediate end points.

Adult↗
PubMed1999

Intestinal metaplasia of human stomach displays distinct patterns of mucin (MUC1, MUC2, MUC5AC, and MUC6) expression.

Intestinal metaplasia is a well-established premalignant condition of the stomach that is characterized by mucin carbohydrate modifications defined by histochemical methods. The purpose of the present study was to see whether the expression of mucin core proteins was modified in the different types of intestinal metaplasia and to evaluate the putative usefulness of mucins as "molecular markers" in this setting. We used a panel of monoclonal antibodies with well-defined specificities to MUC1, MUC2, MUC5AC, and MUC6 to characterize the expression pattern of mucins. In contrast to normal gastric mucosa, the complete form or type I intestinal metaplasia (n = 20) displayed little or no expression of MUC1, MUC5AC, or MUC6 in the metaplastic cells and strong expression of the intestinal mucin MUC2 in the goblet cells of all cases. The incomplete forms of intestinal metaplasia, type II (n = 25) and type III (n = 16), expressed MUC1 and MUC5AC in every case, both in goblet and in columnar cells. MUC6 was also expressed in 16 cases of type II intestinal metaplasia and in 11 cases of type III intestinal metaplasia. The intestinal mucin MUC2 was expressed in every case of incomplete intestinal metaplasia, mostly in goblet cells. The mucin expression profile in the different types of intestinal metaplasia allows the identification of two patterns: one defined by decreased levels of expression of "gastric" mucins (MUC1, MUC5AC, and MUC6) and expression of MUC2 intestinal mucin, which corresponds to type I intestinal metaplasia, and the other defined by coexpression of "gastric mucins" (MUC1, MUC5AC, and MUC6) together with the MUC2 mucin, encompassing types II and III intestinal metaplasia. Our results challenge the classical sequential pathway of intestinal metaplasia (from type I to type III via a type II intermediate step).

Antibodies, Monoclonal↗
PubMed1993

Metaplasia and precursor lesions of gallbladder carcinoma. Frequency, distribution, and probability of detection in routine histologic samples.

BACKGROUND: Gallbladder diseases, especially cholelithiasis, are extremely frequent in Chile, and an increasing frequency of gallbladder carcinoma has been observed during the last decades. Hyperplastic and atypical epithelial lesions of gallbladder epithelium have been considered potential precursors of invasive carcinoma. The current study was designed to study the frequency, distribution, extension, and probability of routine detection of potentially preneoplastic changes of gallbladder epithelium. METHODS: Epithelial changes were histologically studied by mapping gallbladders obtained at elective cholecystectomy for lithiasis in 162 Chilean patients. RESULTS: Antral-type metaplasia was found in 95.1% of the cases, intestinal metaplasia in 58.1%, hyperplasia in 46.9%, dysplasia in 16%, and carcinoma in situ in 2.5%. A significant association of intestinal metaplasia with hyperplasia, intestinal metaplasia with dysplasia, and hyperplasia with dysplasia was found. Hyperplasia and dysplasia were also present in four cases with carcinoma in situ. Mean extension of the lesions (percentages of the sections in which the change was observed) was antral-type metaplasia (62.7%), intestinal metaplasia (25.3%), hyperplasia (24.1%), dysplasia (15.5%), and carcinoma in situ (9.7%). Antral-type and intestinal metaplasia were more extensive and more severe in patients older than 50 years of age. Hyperplasia was more extensive in cases in which it was associated with dysplasia and carcinoma in situ. CONCLUSIONS: The extension of metaplasia seems to depend in part on the age of the patients. The association of intestinal metaplasia with hyperplasia and dysplasia agrees with the findings of other authors that relate metaplasia to gallbladder cancer. The epithelial lesions are focal or partially confluent, thus a single random histologic section will detect less than one third of the hyperplasias, dysplasias, and carcinomas in situ.

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