Barrett Intestinal Metaplasia Research Articles

Computational pathology aids derivation of microRNA biomarker signals from Cytosponge samples.

SummaryBackgroundNon-endoscopic cell collection devices combined with biomarkers can detect Barrett's intestinal metaplasia and early oesophageal cancer. However, assays performed on multi-cellular samples lose information about the cell source of the biomarker signal. This cross-sectional study examines whether a bespoke artificial intelligence-based computational pathology tool could ascertain the cellular origin of microRNA biomarkers, to inform interpretation of the disease pathology, and confirm biomarker validity.MethodsThe microRNA expression profiles of 110 targets were assessed with a custom multiplexed panel in a cohort of 117 individuals with reflux that took a Cytosponge test. A computational pathology tool quantified the amount of columnar epithelium present in pathology slides, and results were correlated with microRNA signals. An independent cohort of 139 Cytosponges, each from an individual patient, was used to validate the findings via qPCR.FindingsSeventeen microRNAs are upregulated in BE compared to healthy squamous epithelia, of which 13 remain upregulated in dysplasia. A pathway enrichment analysis confirmed association to neoplastic and cell cycle regulation processes. Ten microRNAs positively correlated with columnar epithelium content, with miRNA-192–5p and -194–5p accurately detecting the presence of gastric cells (AUC 0.97 and 0.95). In contrast, miR-196a-5p is confirmed as a specific BE marker.InterpretationComputational pathology tools aid accurate cellular attribution of molecular signals. This innovative design with multiplex microRNA coupled with artificial intelligence has led to discovery of a quality control metric suitable for large scale application of the Cytosponge. Similar approaches could aid optimal interpretation of biomarkers for clinical use.FundingFunded by the NIHR Cambridge Biomedical Research Centre, the Medical Research Council, the Rosetrees and Stoneygate Trusts, and CRUK core grants.

Hybrid APC in Combination With Resection for the Endoscopic Treatment of Neoplastic Barrett's Esophagus: A Prospective, Multicenter Study.

INTRODUCTION:The current therapy of neoplastic Barrett's esophagus (BE) consists of endoscopic resection plus ablation, with radiofrequency ablation as the best studied technique. This prospective trial assesses a potential alternative, namely hybrid argon plasma ablation.METHODS:Consecutive patients with neoplastic BE undergoing ablation after curative endoscopic resection (89.6%) or primarily were included into this prospective trial in 9 European centers. Up to 5 ablation sessions were allowed for complete eradication of BE (initial complete eradication of intestinal metaplasia [CE-IM]), by definition including BE-associated neoplasia, documented by 1 negative endoscopy with biopsies. The main outcome was the rate of initial CE-IM in intention-to-treat (ITT) and per-protocol (PP) samples at 2 years. The secondary end points were the rate of recurrence-free cases (sustained CE-IM) documented by negative follow-up endoscopies with biopsies and immediate/delayed adverse events.RESULTS:One hundred fifty-four patients (133 men and 21 women, mean age 64 years) received a mean of 1.2 resection and 2.7 ablation sessions (range 1–5). Initial CE-IM was achieved in 87.2% of 148 cases in the PP analysis (ITT 88.4%); initial BE-associated neoplasia was 98.0%. On 2-year follow-up of the 129 successfully treated cases, 70.8% (PP) or 65.9% (ITT) showed sustained CE-IM; recurrences were mostly endoscopy-negative biopsy-proven BE epithelium and neoplasia in 3 cases. Adverse events were seen in 6.1%.DISCUSSION:Eradication and recurrence rates of Barrett's intestinal metaplasia and neoplasia by means of hybrid argon plasma coagulation at 2 years seem to be within expected ranges. Final evidence in comparison to radiofrequency ablation can only be provided by a randomized comparative trial.

PS02.040: EXPRESSION OF INTESTINAL/NON-INTESTINAL DIFFERENTIATION MARKERS IN ADENOCARCINOMAS OF THE ESOPHAGUS CORRELATES WITH ESOPHAGO-GASTRIC INTESTINAL METAPLASIA

Abstract Background Esophageal adenocarcinomas (EAC), grouped according to the presence (+ )/absence (-) of intestinal metaplasia in esophagus (BIM) and stomach (GIM) differ in terms of nodal metastatic patterns and survival. We studied the differentiation profile in BIM/GIM categories. Methods In 77 EAC surgical specimens we assessed CDX-2, CK7, CK20, MUC1, MUC2, MUC5A/C, MUC6 antibodies. The expression of such markers was correlated with: BIM + GIM- (Barrett-like), BIM-GIM- (cardiopyloric-like), BIM-GIM + (gastric-like). Results CDX2 (P = 0.0481), CK7 (P = 0.0150), MUC2 (P = 0.0395) were differently expressed (Kruskall-Wallis test) in BIM/GIM categories. Binary relations (Mann-Whitney test) showed that CDX2 was more expressed in BIM + /GIM- than in BIM-/GIM- (P = 0.0046) tumors; CK7 was more expressed in BIM-/GIM- than in BIM-/GIM + (P = 0.0020) and in BIM + /GIM- than in BIM-/GIM + (P = 0.0101); MUC2 was more expressed in BIM + /GIM- than in BIM-/GIM- (P = 0.0061). The other investigated markers were randomly distributed among BIM/GIM categories. Conclusion The greater expression of intestinal markers (CDX2-MUC2) in Barrett's intestinal metaplasia associated tumors (BIM + /GIM-) compared to those with no intestinal metaplasia (BIM-/GIM-) is consistent with their predominant intestinal differentiation. In contrast, CK7, although mostly expressed in tumors not associated with intestinal metaplasia (BIM-/GIM-) was less efficient in distinguishing them from those associated with Barrett's metaplasia (BIM + /GIM-) while showed the lowest level of expression in tumors associated with gastric intestinal metaplasia (BIM-/GIM + ). In conclusion, intestinal (CDX2-MUC2) and non-intestinal (CK7) differentiation markers appear to be expressed differently in BIM/GIM categories. Those findings support the opportunity to investigate further biology of these tumors in view of clinical-prognostic implications. Disclosure All authors have declared no conflicts of interest.

Deoxycholic acid promotes development of gastroesophageal reflux disease and Barrett's oesophagus by modulating integrin-αv trafficking.

The fundamental mechanisms underlying erosive oesophagitis and subsequent development of Barrett's oesophagus (BO) are poorly understood. Here, we investigated the contribution of specific components of the gastric refluxate on adhesion molecules involved in epithelial barrier maintenance. Cell line models of squamous epithelium (HET‐1A) and BO (QH) were used to examine the effects of bile acids on cell adhesion to extracellular matrix proteins (Collagen, laminin, vitronectin, fibronectin) and expression of integrin ligands (α3, α4, α5, α6 and αν). Experimental findings were validated in human explant oesophageal biopsies, a rat model of gastroesophageal reflux disease (GORD) and in patient tissue microarrays. The bile acid deoxycholic acid (DCA) specifically reduced adhesion of HET‐1A cells to vitronectin and reduced cell‐surface expression of integrin‐αν via effects on endocytic recycling processes. Increased expression of integrin‐αv was observed in ulcerated tissue in a rat model of GORD and in oesophagitis and Barrett's intestinal metaplasia patient tissue compared to normal squamous epithelium. Increased expression of integrin‐αν was observed in QH BO cells compared to HET‐1A cells. QH cells were resistant to DCA‐mediated loss of adhesion and reduction in cell‐surface expression of integrin‐αν. We demonstrated that a specific component of the gastric refluxate, DCA, affects the epithelial barrier through modulation of integrin αν expression, providing a novel mechanism for bile acid‐mediated erosion of oesophageal squamous epithelium and promotion of BO. Strategies aimed at preventing bile acid‐mediated erosion should be considered in the clinical management of patients with GORD.

Subsquamous intestinal metaplasia is common in treatment-naïve Barrett’s esophagus

Barrett's intestinal metaplasia may extend beneath normal squamous epithelium at the squamocolumnar junction (SCJ) and therefore escape surveillance biopsy sampling. The prevalence of subsquamous intestinal metaplasia (SSIM) in patients undergoing Barrett's esophagus (BE) surveillance is unknown. Our aim was to examine the prevalence and distribution of SSIM proximal to the SCJ in patients undergoing BE surveillance. We enrolled consecutive patients with biopsy specimen-proven BE. Biopsy specimens were obtained from the squamous epithelium at 5mm and 10mm above the SCJ. The primary outcomes were the proportion of patients with SSIM at each level. We further assessed factors associated with SSIM. We examined 515 squamous epithelial biopsy specimens from 106 BE patients (95% men; mean age, 66 years) with a mean Barrett's length of 3.0 cm. SSIM was present in 39% at 5mm (95% CI, 29.4-48.6) and 21% (95% CI, 11.7-32.1) at 10mm proximal to the SCJ. Among all biopsy specimens, 13% (95% CI, 10.6-16.6) contained SSIM: 17% (95% CI, 13-21.6) of biopsy samples at 5mm and 8% (95% CI, 4.3-12.2) at 10mm proximal to the SCJ. SSIM was more common in the anterior/right lateral position compared with the posterior/left lateral position (21% vs 11%, P= .001). None of the biopsy specimens showed dysplasia. Length of BE or duration of reflux symptoms were not associated with the presence of SSIM. This cross-sectional study found a surprisingly high proportion of SSIM in treatment-naïve patients proximal to the SCJ. These findings raise questions regarding BE management and the prevalence of SSIM in normal-appearing esophagus.

Reflux esophagitis and its role in the pathogenesis of Barrett's metaplasia.

Reflux esophagitis damages the squamous epithelium that normally lines the esophagus, and promotes replacement of the damaged squamous lining by the intestinal metaplasia of Barrett's esophagus, the precursor of esophageal adenocarcinoma. Therefore, to prevent the development of Barrett's metaplasia and esophageal adenocarcinoma, the pathogenesis of reflux esophagitis must be understood. We have reported that reflux esophagitis, both in a rat model and in humans, develops as a cytokine-mediated inflammatory injury (i.e., cytokine sizzle), not as a caustic chemical injury (i.e., acid burn), as traditionally has been assumed. Moreover, reflux induces activation of hypoxia inducible factor (HIF)-2α, which enhances the transcriptional activity of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) causing increases in pro-inflammatory cytokines and in migration of T lymphocytes, an underlying molecular mechanism for this cytokine-mediated injury. In some individuals, reflux esophagitis heals with Barrett's metaplasia. A number of possibilities exist for the origin of the progenitor cells that give rise to this intestinal metaplasia including those of the esophagus, the proximal stomach, or the bone marrow. However, intestinal cells are not normally found in the esophagus, the stomach, or the bone marrow. Thus, the development of Barrett's intestinal metaplasia must involve some molecular reprogramming of key developmental transcription factors within the progenitor cell, a process termed transcommitment, which may be initiated by the noxious components of the gastric refluxate. This review will highlight recent studies on the pathogenesis of reflux esophagitis and on reflux-related molecular reprogramming of esophageal squamous epithelial cells in the pathogenesis of Barrett's metaplasia.

Evaluation of Mutational Testing of Preneoplastic Barrett's Mucosa by Next-Generation Sequencing of Formalin-Fixed, Paraffin-Embedded Endoscopic Samples for Detection of Concurrent Dysplasia and Adenocarcinoma in Barrett's Esophagus

Barrett's intestinal metaplasia (BIM) may harbor genomic mutations before the histologic appearance of dysplasia and cancer and requires frequent surveillance. We explored next-generation sequencing to detect mutations with the analytical sensitivity required to predict concurrent high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) in patients with Barrett's esophagus by testing nonneoplastic BIM. Formalin-fixed, paraffin-embedded (FFPE) routine biopsy or endoscopic mucosal resection samples from 32 patients were tested: nonprogressors to HGD or EAC (BIM-NP) with BIM, who never had a diagnosis of dysplasia or EAC (N = 13); progressors to HGD or EAC (BIM-P) with BIM and a worse diagnosis of HGD or EAC (N = 15); and four BIM-negative samples. No mutations were detected in the BIM-NP (0 of 13) or BIM-negative samples, whereas the BIM-P samples had mutations in 6 (75%) of 8 cases in TP53, APC, and CDKN2A (P=0.0005), detected in samples with as low as 20% BIM. We found that next-generation sequencing from routine FFPE nonneoplastic Barrett's esophagus samples can detect multiple mutations in minute areas of BIM with high analytical sensitivity. Next-generation sequencing panels for detection of TP53 and possibly combined mutations in other genes, such as APC and CDKN2A, may be useful in the clinical setting to improve dysplasia and cancer surveillance in patients with Barrett's esophagus.

The role of acetic acid in the management of Barrett's oesophagus

Barrett's oesophagus is of significant importance due to its premalignant potential. Acetic acid chromoendoscopy is a simple technique that can be used with any endoscope system. It has been utilised for the identification of Barrett's intestinal metaplasia; and more importantly, for the localisation of early neoplasia within Barrett's, which is often focal, subtle and very easy to miss by random quadrantic biopsies alone. Acetic acid is routinely utilised in specialised centres and its use is expanding. This article examines the evidence base behind acetic acid chromoendoscopy and looks at where further research needs to be directed.

Early metal stent insertion fails to prevent stricturing after single-stage complete Barrett's excision for high-grade dysplasia and early cancer

Barrett's esophagus with high-grade dysplasia (HGD) or intramucosal adenocarcinoma (IMC) can be effectively treated by single-session EMR, resulting in complete Barrett's excision (CBE). CBE provides accurate histology for staging and clinical confirmation of neoplasia eradication but is limited by a high risk of esophageal stricture formation. To evaluate the effectiveness of prophylactic temporary esophageal stenting to prevent post-CBE stricture formation. Single-center, investigator-initiated feasibility study. Circumferential, short-segment Barrett's esophagus (≤C3≤M5) with HGD or IMC. Single-stage CBE and insertion of a fully covered metal esophageal stent at 10 days that was removed at 8 weeks. Patients were followed for a minimum of 2 surveillance endoscopies. Symptomatic esophageal stricture formation. At the end of the follow-up period, 8 patients (57.1%) required esophageal dilation for symptomatic CBE-related (n= 7) or stent-related (n= 4) strictures. A median of 3 surveillance endoscopies were performed over a median endoscopic follow-up of 17 months (range 4-25 months). Single-stage CBE successfully eliminated Barrett's intestinal metaplasia and neoplasia in 71.4% and 92.9% of patients, respectively. Four patients were admitted to the hospital, and 4 patients had early stent removal because of pain or dysphagia. Single-center feasibility study. In a prospective study evaluating prophylactic esophageal stent insertion after single-stage CBE, esophageal strictures formed in more than of half the study cohort, and stents were associated with significant morbidity. An alternative method to reduce stricture formation is required. ( NCT01554280.).

Radiofrequency Ablation for Barrett Esophagus With Confirmed Low-Grade Dysplasia

The incidence of Barrett adenocarcinoma is increasing substantially and was estimated at 2.8 cases per 100 000 people in the United States in 2010.1 Given the premalignant potential of Barrett intestinal metaplasia, it would be logical to simply eliminate preneoplastic tissue. Indeed, if Barrett esophagus was a focally localized, raised, and easily recognizable lesion (ie, polyp), endoscopic removal would be a relatively easy task, and there would be no discussion about how to prevent neoplastic progression in these patients.

P16 gene mutations in Barrett's esophagus in gastric metaplasia – intestinal metaplasia – dysplasia – adenocarcinoma sequence

Barrett's associated esophageal adenocarcinoma (ADC) is one of the malignancies of most rapidly increasing incidence. The aim of the study was to assess p16 tumor suppressor gene alterations in the ADC premalignant conditions. In the present study two p16 gene mutations (A148T and I49S) analysis with PCR- RFLP method have been performed in oesophageal biopsy specimen in 33 patients with Barrett's gastric metaplasia (GM), 27 - with Barrett's intestinal metaplasia (IM), 8 - with dysplasia and 11 - with ADC. We have detected the I49S mutation in 12% (4/33) patients with GM, 18% (5/27) with IM, 50% - with dysplasia (4/8) and in 27% (3/11) - with ADC. The A148T mutation were found in 3% (1/33) patients with GM, 22% (6/27) - IM, 25% (2/8) - dysplasia and 27% patients with ADC (3/11). The frequency of the A148S mutation was rising in GM - IM - dysplasia - ADC sequence and was significantly lower in GM compared to all other grades taken together (p=0.0256). The frequency of the I49S mutation was rising in GM - IM - dysplasia sequence, to drop in ADC cases. There were no significant differences in frequency of the I49S mutation between studied groups. These findings are consistent with the hypothesis on the role of the p16 mutations in early phase of Barrett's epithelium progression to ADC. The presence of p16 mutations in esophageal metaplastic columnar epithelium without goblet cells suggest that this pathology may have malignancy potential.

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.

The role of mucin in GERD and its complications

Acid, pepsin and other noxious material reach the esophageal mucosa and interact with the luminal aspect of the squamous epithelium. The first protective barrier to these potentially injurious substances is the mucus buffer layer that covers the mucosa. In healthy people, the esophagus has a protective surface adherent mucus gel barrier. Levels of mucin glycoprotein are considerably increased in response to acid and pepsin. A wide spectrum of mucin genes are expressed in normal esophageal mucosa, squamous cell carcinoma of the esophagus, Barrett epithelium and esophageal adenocarcinoma. The mucins MUC5AC and MUC6 are expressed to a similar degree in Barrett metaplasia and gastric mucosa, as is MUC2 in Barrett intestinal metaplasia and small bowel mucosa. Increased expression of MUC1 is associated with progression from dysplasia to adenocarcinoma of the esophagus. Thus, mucins have an important role in the defense of esophageal mucosa against the acid, pepsin and bile that are present in the refluxate. Changes in the expression of mucins occur in patients with GERD, and might lead to the development of new drugs.

Su1468 Subsquamous Intestinal Metaplasia Is Common At the Squamocolumnar Junction in Native Barrett's Esophagus

Barrett intestinal metaplasia (IM) may extent beneath normal squamous epithelium at the squamocolumnar junction (SCJ) and hence escape surveillance biopsies or endoscopic therapy of Barrett dysplasia. The magnitude of subsquamous intestinal metaplasia in native Barrett's esophagus is unknown.

Gene expression alterations in formalin-fixed, paraffin-embedded Barrett esophagus and esophageal adenocarcinoma tissues.

Background and aim: Widespread applicability of tissue-based mRNA expression screening for Barrett esophagus (BE) is likely to require (1) accurate methods for assaying archival formalin-fixed, paraffin-embedded (FFPE) histopathology specimens taken at endoscopy, and (2) validation studies of promising biomarkers in different patient cohorts.Results: 30 genes were significantly differentially expressed by histopathology tissue type. The direction and magnitude of the differences were very similar to those found in previous studies using fresh frozen tissues. Novel upregulated genes were TSPAN8 (also known as CO-029), TSPAN24 (CD151), EGR1 and TCIRG1. Novel downregulated genes were DPYD, TSPAN29 (CD9) and Ets1. Strong associations between histopathology type and gene expression were observed with the overexpressed genes: cyclo-oxygenase-2 (COX-2), for which histopathology type explained 77.7% of the variation in expression, TSPAN1 (73.5%), TSPAN8 (62.9%), SPARC (62.1%), MMP7 (50.8%); and the under-expressed genes ADH7 (53.7%), APC (58.2%), RAR-gamma (51.3%).Methods: mRNA was isolated from 54 FFPE small endoscopic biopsies from patients with Barrett intestinal metaplasia (BE), esophageal adenocarcinoma (EAC), or control patients with a normal squamous-lined esophagus. Multiplexed tandem PCR (MT-PCR) was used to quantitate 50 selected candidate genes for BE and control genes in duplicate. Principal component analysis (PCA) was conducted to explore the presence of global differences in gene expression profiles. One-way analysis of variance (ANOVA) of the transformed data was used to identify genes that were differentially expressed between different histological subtypes. Differentially expressed genes with a fold change of ≥2 (upregulated) or ≤-2 (downregulated) are reported with the p value for each comparison (EAC vs. normal, EAC vs. BE and BE vs. normal). The Benjamini-Hochberg method was used to control the false discovery rate at 0.01 for all comparisons.Conclusions: Alterations in expression of select genes are strongly associated with BE or EAC or both. This study's findings for many highly differentially expressed genes are very similar to those previously reported, suggesting that these genes should be tested further in longitudinal studies for their potential role as biomarkers of progression to more advanced Barrett disease.

CDX2 and LI-Cadherin Expression in Esophageal Mucosa: Use of Both Markers Can Facilitate the Histologic Diagnosis of Barrett’s Esophagus and Carcinoma

Barrett's mucosa is a risk factor for esophageal adenocarcinoma and should be detected at an early stage. CDX2 and liver-intestine (LI)-cadherin are intestine-specific markers. Aberrant CDX2 expression has been demonstrated in Barrett's metaplasia, esophagitis, and intestinal metaplasia of the stomach. The relationship between CDX2 and LI-cadherin expression was investigated in normal gastroesophageal (n = 24) and in Barrett's (n = 20) mucosa, in low-grade (n = 15) and high-grade (n = 13) intraepithelial neoplasia (IEN) as well as in esophageal adenocarcinoma (n = 16), using immunohistochemistry. Nuclear positivity for CDX2 coupled with membranous expression of LI-cadherin was observed in about 70% of the epithelial cells of Barrett's mucosa. The intensity of staining and the percentage of positive cells increased within the sequential steps of low-grade to high-grade IEN, whereas the normal cylindric epithelium lacked the expression of both. In adenocarcinoma, the expression of LI-cadherin and CDX2 was significantly weaker or absent. CDX2 and LI-cadherin are sensitive markers of intestinal metaplasia with or without dysplasia in the upper gastrointestinal tract. Both can be helpful for the early histologic diagnosis of Barrett's esophagus and its subsequent lesions; however, they do not significantly discern between different grades of dysplasia.

Expression of the putative stem cell marker Musashi-1 in Barrett's esophagus and esophageal adenocarcinoma

The cancer stem cell theory states that cancers contain tumor-forming cells that have the ability to self-renew as well as give rise to cells that differentiate. Cancer stem cells have been identified in several solid tumors, but stem cells in normal human esophagus or in Barrett's esophagus or adenocarcinoma have not been reported. Musashi-1 is expressed by the crypt base columnar cells identified as intestinal stem cells. In other diseases of the gastrointestinal tract, local inflammation of the tunica mucosa may be an initiating factor of alteration of focal tissue 'niches,' where dormant stem cells locate. The present study investigated whether Musashi-1 is expressed in the esophagus and its relation to immune inflammation of the mucosa in Barrett's esophagus and esophageal adenocarcinoma. A total of 41 esophageal tissue specimens from 41 patients were studied. Of these, 15 were esophageal adenocarcinoma, 17 were Barrett's esophagus (10 intestinal metaplasia and 7 dysplasia), and 9 were normal squamous esophagus tissue specimens from patients without esophageal pathology. Immunohistochemistry was performed using antibodies to Musashi-1 and to a set of cell type-specific markers. A multiplexed tandem polymerase chain reaction method was used to measure the relative mRNA expression levels of Musashi-1 and the specific dendritic cell marker dendritic cell-specific intercellular molecule-3 (ICAM-3)-grabbing nonintegrin. Immunohistochemistry demonstrated the presence of small numbers of Musashi-1+ cells scattered in the connective tissue stroma and within the epithelium in cardiac-type glands in biopsies from patients without Barrett's esophagus. Musashi-1 expression was present in Barrett's intestinal metaplasia and in dysplastic Barrett's in which the majority of epithelial cells in individual glands expressed this antigen. Expression of Musashi-1 was highest in esophageal adenocarcinoma, where it was most intense in glands that displayed features of early stages of adenocarcinoma formation. In contrast, Musashi-1 staining level was weaker in glands that displayed features of advanced adenocarcinoma. Double immunostaining with proliferating cell nuclear antigen showed low proliferation in the vast majority of Musashi-1+ cells. Musashi-1 mRNA expression levels were significantly higher in esophageal adenocarcinoma than in normal esophagus or Barrett's esophagus tissues. Dendritic cell-specific intercellular molecule-3 (ICAM-3)-grabbing nonintegrin (DC-SIGN) mRNA expression levels were significantly increased in both Barrett's tissues and adenocarcinoma tissues. Expression of the putative stem cell marker Musashi-1 is absent in normal squamous epithelium, weak in esophageal cardiac-type glands and Barrett's esophagus, and markedly increased in adenocarcinoma, especially in glands displaying features of early cancer development. Musashi-1 expressing cells may be significant in the etiology of Barrett's esophagus and adenocarcinoma, and perhaps even a cell of origin for this disease. We speculate that immune inflammation occurring in Barrett's esophagus alters the mucosal microenvironment in a manner which is favorable to the activation of dormant stem cells.

Esophageal Polypoid Dysplasia of Gastric Foveolar Phenotype With Focal Intramucosal Carcinoma Associated With Barrett's Esophagus

We describe a rare case of esophageal polypoid dysplasia with gastric phenotype and focal intramucosal carcinoma associated with Barrett's esophagus. A 69-year-old man with a long history of gastroesophageal reflux disease was initially seen at an outside institution for evaluation of significant dysphagia. Screening upper gastrointestinal endoscopic evaluation revealed a large intraluminal polypoid lesion occluding the distal portion of the esophagus. Surgery was performed with resection of the distal esophagus and proximal stomach. The histopathologic examination of this lesion revealed an exuberant polypoid gastric epithelium with areas of low-grade dysplasia, high-grade dysplasia, and focal intramucosal carcinoma. A few residual foci of specialized intestinal metaplasia consistent with Barrett's esophagus without dysplasia were identified at the proximal and distal ends of the lesion. Immunohistochemically, this lesion revealed a pattern of expression of apomucins (MUC5AC diffusely positive, MUC1 and MUC6 focally positive, and MUC2 negative) consistent with a gastric foveolar phenotype. In addition, in the dysplastic areas, there was high Ki-67 labeling index and no overexpression of p53 protein. In our opinion, this case represents a precursor lesion of an extremely well-differentiated adenocarcinoma of gastric foveolar phenotype that has been previously documented in the stomach and in the duodenum and that now for the first time we report in the esophagus in association with Barrett's intestinal metaplasia.

W1832 Barrett's Intestinal Metaplasia mRNA Expression Profile in Formalin-Fixed, Paraffin-Embedded Endoscopic Biopsy Specimens

W1832 Barrett's Intestinal Metaplasia mRNA Expression Profile in Formalin-Fixed, Paraffin-Embedded Endoscopic Biopsy Specimens

Barium study associated with water siphon test in gastroesophageal reflux disease and its complications

The aim of this study was to evaluate the role of digital cineradiography associated with the water siphon test (WST) in the diagnosis of gastroesophageal reflux and to compare the results with oesophageal motility study, pH monitoring and endoscopy associated with biopsy and histology. One hundred and sixty consecutive patients underwent digital cineradiography with WST, motility study, pH monitoring and endoscopy with biopsy. The presence of gastroesophageal reflux, oesophagitis, Barrett's oesophagus and intestinal metaplasia was evaluated. WST vs. pH monitoring showed sensitivity of 71%, specificity of 31%, positive predictive value (PPV) of 53% and negative predictive value (NPV) of 50%; when middle-proximal refluxes only were considered, sensitivity decreased to 45% and specificity increased to 55%. Furthermore, the association between reflux and oesophagitis demonstrated by the chi-square (chi(2)) test proved to be statistically significant both for WST and pH monitoring, whereas the association between reflux and Barrett's oesophagus was not significant for either WST or for pH monitoring. With regard to intestinal metaplasia, WST (middle-proximal refluxes) showed higher sensitivity (64% vs. 58%) and specificity (63% vs. 51%) than pH monitoring, whereas the statistical association between reflux and metaplasia proved to be significant for WST but not for pH monitoring. WST is a simple, inexpensive and reliable test that might be useful in the diagnosis of gastroesophageal reflux disease (GERD). A positive WST might be an additional indication for endoscopy with biopsy.