Barrett's Esophagus Intestinal Metaplasia Research Articles

Structural alterations of the mucosa stroma in the Barrett's esophagus metaplasia‐dysplasia‐adenocarcinoma sequence

Accumulating evidence suggests that the extracellular matrix play important roles in intercellular communications and contribute to the development of a number of diseases, including diseases of the gastrointestinal tract. The present study examined the structural characteristics and alterations of the extracellular matrix of the mucosa stroma in the Barrett's esophagus metaplasia-dysplasia-adenocarcinoma sequence. A total of 41 esophageal tissue specimens (15 esophageal adenocarcinoma, 10 Barrett's esophagus intestinal metaplasia, seven dysplasia and nine normal esophagus) were studied. The present study used transmission electron microscopy and computerized quantitative electron-microscopic analysis in order to investigate the characteristics of the extracellular matrix of the mucosa. The study revealed that marked structural alterations of the mucosa stroma, relating to changes in the distribution and appearance of collagen fibers as well as to changes in numbers of matrix microvesicles, occur in Barrett's esophagus and esophageal adenocarcinoma. It was found that there were 3.1 times more microvesicles in the stroma in Barrett's esophagus than in the stroma of the normal esophagus (P<0.0001) and that there were 5.8 times more microvesicles in esophageal adenocarcinoma than in the normal esophagus (P<0.0001). There were 1.9 times more microvesicles in esophageal adenocarcinoma than in Barrett's esophagus (P=0.0043). The study demonstrates distinctive alterations of the mucosa stroma extracellular matrix in the metaplasia-dysplasia-adenocarcinoma sequence. The findings suggest that the redistribution of collagen fibers and increases in numbers of matrix microvesicles may play roles in the formation of specialized intestinal metaplasia and the development of adenocarcinoma.

Anterior gradient 2 profiling in Barrett columnar epithelia and adenocarcinoma

Barrett esophagus is the precancerous lesion leading to Barrett adenocarcinoma. The natural history of Barrett metaplasia and its neoplastic progression are still controversial. Anterior gradient 2 is up-regulated in both Barrett intestinal metaplasia and Barrett adenocarcinoma, but no information is available on anterior gradient 2 expression in the spectrum of the phenotypic changes occurring in the natural history of Barrett adenocarcinoma (Barrett esophagus cardiac-type metaplasia, Barrett esophagus intestinal metaplasia, low-grade intraepithelial neoplasia [formerly called low-grade dysplasia], and high-grade intraepithelial neoplasia [formerly called high-grade dysplasia]). Applying immunohistochemistry and reverse transcription and quantitative real-time polymerase chain reaction, this study addressed the role of anterior gradient 2 in Barrett carcinogenesis. Anterior gradient 2 expression was assessed semiquantitatively in 125 consecutive biopsy samples in the adenocarcinoma spectrum arising in Barrett esophagus (Barrett esophagus cardiac-type metaplasia, 25; Barrett esophagus intestinal metaplasia, 25; low-grade intraepithelial neoplasia, 25; high-grade intraepithelial neoplasia, 25; Barrett adenocarcinoma, 25). Additional biopsy samples of esophageal squamous mucosa (n=25) served as controls. Anterior gradient 2 messenger RNA expression was also tested (reverse transcription and quantitative real-time polymerase chain reaction) in a different series of 40 samples (esophageal squamous mucosa, 10; Barrett esophagus cardiac-type metaplasia, 10; Barrett esophagus intestinal metaplasia, 10; Barrett adenocarcinoma, 10). Anterior gradient 2 was never expressed in squamous esophageal epithelium but consistently overexpressed (to much the same degree) in the whole spectrum of Barrett disease (Barrett esophagus cardiac-type metaplasia, Barrett esophagus intestinal metaplasia, low-grade intraepithelial neoplasia, high-grade intraepithelial neoplasia, and Barrett adenocarcinoma). Anterior gradient 2 messenger RNA was expressed significantly more in Barrett esophagus cardiac-type metaplasia, Barrett esophagus intestinal metaplasia, and Barrett adenocarcinoma than in native squamous epithelium (P<.001), with no significant differences between the 3 groups. Anterior gradient 2 overexpression affects the whole spectrum of the metaplastic/neoplastic lesions involved in Barrett carcinogenesis. This study supports the biological similarity of the nonintestinal and intestinal types of Barrett metaplasia as precursors of Barrett adenocarcinoma.

Expression of Resistin-like Molecule Beta in Barrett’s Esophagus: A Novel Biomarker for Metaplastic Epithelium

The formation of goblet cells characterizes the intestinal metaplasia of Barrett's esophagus (BE). Hematoxylin-eosin (HE) staining may fail to show intestinal metaplasia in BE, and PAS-Alcian Blue may present difficulties of interpretation due to its more heterogeneous staining. Recent evidence indicates that expression of resistin-like molecule beta (RELMbeta), a goblet cell-specific protein, is uniquely restricted to intestinal epithelium. However, it still remains largely unknown whether RELMbeta can be served as a biomarker for metaplastic epithelium of BE. In this study, 104 biopsy specimens of the distal esophagus from 88 suspected BE patients were collected, including 56 suspected intestinal metaplasia, 26 gastric type mucosa, and 22 squamous epithelium. We evaluated the RELMbeta expression in these biopsy specimens, and compared with those of CDX-2 immunostaining and PAS-Alcian Blue staining (pH 2.5). Of the suspected intestinal metaplasia specimens, 46 presented intestinal-type goblet cells and were immunostaining positive for RELMbeta and CDX-2, the remaining ten possessed only goblet cell mimickers and were not reactive with RELMbeta and CDX-2. Of the gastric-type mucosa specimens, none reacted with either RELMbeta or CDX-2. Moreover, the squamous epithelium was not reactive with RELMbeta and CDX-2. Acid mucin was present in goblet cells in all cases of BE and columnar cells in ten gastric specimens. In addition, the reactivity of RELMbeta was enhanced in six BE specimens with dysplasia. These results provide evidence that RELMbeta protein may be a novel biomarker to distinguish the intestinal-type goblet cells and goblet cell mimickers, and useful in the correct diagnosis of BE.

Mucin expression profile in Barrett′s, dysplasia, adenocarcinoma sequence in the esophagus

The molecular events that accompany the progression to adenocarcinoma (ADC) of the esophagus are poorly understood. Aberrant mucin receptor expression can contribute to increased cell growth and metastatic ability. The aim of this study was to establish a pattern for mucin (MUC) gene expression in the esophageal mucosa under normal and pathological conditions. University Hospital Cancer Center Laboratory. Archived tissue samples studied in a retrospective fashion. Tissue samples were obtained from the archives of patients with histological evidence of Barrett's esophagus (BE) progressing to ADC. Immunohistochemical analysis was performed using mouse monoclonal antibodies for MUC1, MUC2, MUC5AC, MUC6. Semiquantitative scoring of histological staining was performed using a linear scoring system: 0-staining absent; 1-staining in 0-25%; 2-staining in 25-50%; and 3-staining in 50-75% of the epithelium. The Binomial test was used to explore trends and differences in frequency of mucin expression along the pathological sequence. Only mild superficial staining of MUC1 was seen in normal squamous epithelium. MUC1 and MUC2 were uniformly expressed in all samples (7/7) of BE and dysplasia (P=0.008). MUC1 expression was upregulated (7/7) in progression to adenocarcinoma (P=0.008). The secretory mucins, MUC5AC and MUC6 showed a decrease in expression with progression from BE to dysplasia to ADC (P< 0.05). Downregulation of MUC5AC and MUC6 decreases mucosal protection against gastric acid. Increasing MUC1 expression is associated with progression from dysplasia to ADC. Upregulation of MUC2 reflects intestinal metaplasia in BE.

Usefulness of Cytokeratin CK7 and CK20 in the Diagnosis of Barrett's Esophagus (BE)

Diagnosis of BE is hinged on the presence of intestinal metaplasia (IM) and inflammation in the lower esophagus. However IM can occur in the cardia and lower esophagus following reflux and helicobacter infection. The special stain for demonstrating intestinal metaplasia cannot distinguish IM in BE and that in cardia or lower esophagus due to other causes(1). Quite often biopsies labeled lower esophagus by the endoscopist may in fact be from the cardia especially in cases where the gastro-esophageal junction is indistinct.

Diagnostic accuracy of magnifying chromoendoscopy with detection of intestinal metaplasia and dysplasia using acetic acid in Barrett's esophagus

Endoscopy with systematic randomized biopsies aims to improve the detection of intestinal metaplasia (IM) and dysplasia in Barrett's esophagus (BE). Magnifying chromoendoscopy with alcoholic acetic acid might allow directed biopsies to improve detection of IM and dysplasia. Twenty-eight patients were studied with magnifying chromoendoscopy (Optical power zoom x 115, alcoholic acetic acid). Endoscopy biopsies were performed on one or several zones of BE chosen randomly, for which the chromoendoscopic pattern was determined according to Guelrud's classification. Among seventy-two biopsies, the agreement between magnifying chromoendoscopy and histology and the positive predictive value of the association of patterns III and IV for the diagnosis of IM were 72.4%; sensibility and specificity were respectively 95.5% and 42.9%. The diagnostic accuracy was 75%. Among the six biopsies that showed high-grade dysplasia, three were suspected because of two particular patterns: local loss of ridged cerebriform pattern due to the disorganization of the mucosal folds and hypervascularization of the mucosa. Magnifying chromoendoscopy with acetic acid allows targeted biopsies of the IM in BE and may help to detect high-grade dysplasia.

Hepatocyte paraffin 1 immunoexpression in esophageal brush samples

Intestinal metaplasia (IM) is often a component of Barrett esophagus (BE) and is characterized by a distinctive type of epithelium. Because IM has the potential to progress to dysplasia or adenocarcinoma, an accurate identification of its presence is important clinically. A cytopathologic diagnosis of IM on esophageal brushings by morphology alone can be difficult. The authors investigated the role of hepatocyte paraffin 1 (Heppar-1) immunostaining as a possible marker of IM in cytologic samples of BE. Eleven samples each of BE with and without IM diagnosed on esophageal brushings were retrieved from the cytopathology files of The Johns Hopkins Hospital over an 8-year period (1993-2001). All 22 specimens were confirmed histologically on subsequent tissue biopsies. Slides initially were prepared by cytospin and stained with Papanicolaou stain. After destaining, the slides were immunostained with hepatocyte paraffin 1 (Heppar-1) antibody at 1:100 dilution employing conventional methodology. Among the samples of BE with IM, 9 of 11 samples (82%) were immunoreactive for Heppar-1, compared with 0 of 11 specimens of BE with only cardiac-type metaplasia. The immunoexpression was cytoplasmic and granular and was seen only focally in the glandular fragments. Heppar-1 was a moderately sensitive (82%) and highly specific (100%) immunomarker for IM in BE. It was easy to use in limited cytologic samples that originally were stained with Papanicolaou stain and is recommended for inclusion in morphologically difficult samples of BE with questionable IM. The immunostaining pattern predominantly was focal, necessitating a careful evaluation of positive reactions on cytologic samples.

Barrett's esophagus is characterized by expression of gastric-type mucins (MUC5AC, MUC6) and TFF peptides (TFF1 and TFF2), but the risk of carcinoma development may be indicated by the intestinal-type mucin, MUC2

Barrett's esophagus (BE) consists of metaplastic epithelium of the esophagus, generally diagnosed by mucin histochemistry. We aimed to determine which mucins were expressed in BE, and to relate their expression to BE pathology. Archival biopsies of 4 patient groups were selected, based on standard histochemistry: BE without inflammation, BE with inflammation, ulcerating BE, and BE with dysplasia. Sections were stained by immunohistochemistry for secretory mucins (MUC2, MUC5AC, MUC5B, and MUC6), the proliferation marker Ki-67, and mucin-associated trefoil factor family (TFF) peptides (TFF1, TFF2, and TFF3). MUC5AC and TFF2 were expressed at similar high levels in each clinical group. Intestinal metaplasia (IM), detected both histochemically and by the intestinal mucin MUC2, was lowest in inflamed BE. The expression of the intestinal-type TFF3 did not differ among the groups. Ulcerating BE was distinguished by very low expression of MUC6 and MUC5B, but very high expression of TFF1. Proliferation was not different among the groups. In the total group of BE patients, H. pylori infection of the stomach correlated with decreased TFF2 expression in the BE epithelium. We conclude that BE is best characterized by the specific expression of the gastric-type markers, MUC5AC, MUC6, TFF1, and TFF2. Ulcerating BE constitutes the most distinguished group with respect to mucin and TFF expression. Of the intestinal markers, MUC2 is very specific for IM in BE, whereas TFF3 is not a marker for IM. The low occurrence of IM in inflamed BE suggests that these patients may have the lowest risk of developing carcinoma. Hum Pathol 33:660-668. Copyright 2002, Elsevier Science (USA). All rights reserved.

3521 METHYLENE BLUE CAN DISCLOSE INTESTINAL METAPLASIA IN BARRETT'S ESOPHAGUS?

Barrett's esophagus(BE)is a change in the esophageal epithelium of any lenght that can be recognized at endoscopy and is confirmed to have intestinal metaplasia(IM)by biopsy. Intestinal metaplasia of the esophagus is the premalignant lesion for adenocarcinoma.Multiple biopsies are necessary because of the often focal nature of IM, dysplasia and cancer in these patients. Methylene blue(MB)is a vital stain taken up by actively absorting tissues, such as small intestinal and colonic epithelium. The potential of MB directed biopsy for intestinal metaplasia in BE was suggested in a pilot study by Canto et al.We report preliminary results of a study that prospectively evaluated the use of MB staining in patients previously proven to have BE. Methods:A total of 30 patients underwent upper G.I endoscopy with 0.5% MB staining after cleaning the mucosa with 10% solution of N-acetylcystein.Water was gently sprayed on the esophageal mucosa to wash off excess dye.Positive staining was defined as blue-stained esophageal mucosa that persisted despite water irrigation. Biopsy specimens from positively stained and negatively stained mucosa were obtained and compared.All specimens were independently examined by two pathologists. The mean lenght of BE was 5.7 cm(range 2 to 14)and 18 subjects had long barrett's and 12 with short barrett's. We obtained 296 endoscopic biopsy specimens from stained and nonstained ares(medium 9.86 biopsies/patient, see table). The sensitivity, specificity, positive predictive value and negative predictive value of MB staining for detecting IM was 73%, 59%, 93% and 21% respectively. Conclusion: In patients previously diagnosed to have Barrett's esophagus MB had good sensitivity but a hight frequency of false negatives.