Controversies of the cardiac mucosa and Barrett's oesophagus

Revisiting the Mucosa of the Gastric Cardia: A Scope to Modify an Upper Gastrointestinal Endoscopy

Introduction The mucosa in the cardiac region of the stomach has been less understood. Cardiac mucosa (CM) with less parietal and oxyntic cells has been defined as a normal mucosa. Studies have shown that CM can be the result of occult reflux. Oxyntic mucosa (OM) is normal, and it changes to CM with age. In advancing age, it is more common to find CM instead of OM and oxyntocardiac mucosa (OCM). This study is an attempt to examine the distribution of the three different types of mucosa in various age groups. Materials and methods The study was conducted in the Department of Anatomy and Department of Forensic Medicine and Toxicology of Gauhati Medical College, Guwahati, Assam, India, from 2017 to 2019. Once the stomach was opened, histological specimens were prepared, and the type of mucosa was observed and recorded. Then, the distribution of the types of mucosa in various age groups was analyzed. Results The distribution of mucosa varies significantly across different age groups, and CM increases with age. Conclusion Our present study suggests that CM frequency increases with age. This is in accordance with studies that suggest that CM is a result of occult reflux with age. This observation creates a scope to revise the approaches for upper gastrointestinal (GI) endoscopy.

Signaling Pathways in the Pathogenesis of Barrett's Esophagus and Esophageal Adenocarcinoma

Barrett's esophagus (BE) is a premalignant lesion that can develop into esophageal adenocarcinoma (EAC). The development of Barrett's esophagus is caused by biliary reflux, which causes extensive mutagenesis in the stem cells of the epithelium in the distal esophagus and gastro-esophageal junction. Other possible cellular origins of BE include the stem cells of the mucosal esophageal glands and their ducts, the stem cells of the stomach, residual embryonic cells and circulating bone marrow stem cells. The classical concept of healing a caustic lesion has been replaced by the concept of a cytokine storm, which forms an inflammatory microenvironment eliciting a phenotypic shift toward intestinal metaplasia of the distal esophagus. This review describes the roles of the NOTCH, hedgehog, NF-κB and IL6/STAT3 molecular pathways in the pathogenesis of BE and EAC.

Barrett's Esophagus: An Updated Review

Barrett’s esophagus (BE) is a change in the distal esophageal mucosal lining, whereby metaplastic columnar epithelium replaces squamous epithelium of the esophagus. This change represents a pre-malignant mucosal transformation which has a known association with the development of esophageal adenocarcinoma. Gastroesophageal reflux disease is a risk factor for BE, other risk factors include patients who are Caucasian, age > 50 years, central obesity, tobacco use, history of peptic stricture and erosive gastritis. Screening for BE remains selective based on risk factors, a screening program in the general population is not routinely recommended. Diagnosis of BE is established with a combination of endoscopic recognition, targeted biopsies, and histologic confirmation of columnar metaplasia. We aim to provide a comprehensive review of the epidemiology, pathogenesis, screening and advanced techniques of detecting and eradicating Barrett’s esophagus.

Kyoto international consensus report on anatomy, pathophysiology and clinical significance of the gastro-oesophageal junction

OBJECTIVE

An international meeting was organised to develop consensus on (1) the landmarks to define the gastro-oesophageal junction (GOJ), (2) the occurrence and pathophysiological significance of the cardiac gland, (3) the definition of the gastro-oesophageal junctional zone (GOJZ) and (4) the causes of inflammation, metaplasia and neoplasia occurring in the GOJZ.

DESIGN

Clinical questions relevant to the afore-mentioned major issues were drafted for which expert panels formulated relevant statements and textural explanations.A Delphi method using an anonymous system was employed to develop the consensus, the level of which was predefined as ≥80% of agreement. Two rounds of voting and amendments were completed before the meeting at which clinical questions and consensus were finalised.

RESULTS

Twenty eight clinical questions and statements were finalised after extensive amendments. Critical consensus was achieved: (1) definition for the GOJ, (2) definition of the GOJZ spanning 1 cm proximal and distal to the GOJ as defined by the end of palisade vessels was accepted based on the anatomical distribution of cardiac type gland, (3) chemical and bacterial (Helicobacter pylori) factors as the primary causes of inflammation, metaplasia and neoplasia occurring in the GOJZ, (4) a new definition of Barrett's oesophagus (BO).

CONCLUSIONS

This international consensus on the new definitions of BO, GOJ and the GOJZ will be instrumental in future studies aiming to resolve many issues on this important anatomic area and hopefully will lead to better classification and management of the diseases surrounding the GOJ.

Follow the Metaplasia: Characteristics and Oncogenic Implications of Metaplasia's Pattern of Spread Throughout the Stomach

The human stomach functions as both a digestive and innate immune organ. Its main product, acid, rapidly breaks down ingested products and equally serves as a highly effective microbial filter. The gastric epithelium has evolved mechanisms to appropriately handle the myriad of injurious substances, both exogenous and endogenous, to maintain the epithelial barrier and restore homeostasis. The most significant chronic insult that the stomach must face is Helicobacter pylori (Hp), a stomach-adapted bacterium that can colonize the stomach and induce chronic inflammatory and pre-neoplastic changes. The progression from chronic inflammation to dysplasia relies on the decades-long interplay between this oncobacterium and its gastric host. This review summarizes the functional and molecular regionalization of the stomach at homeostasis and details how chronic inflammation can lead to characteristic alterations in these developmental demarcations, both at the topographic and glandular levels. More importantly, this review illustrates our current understanding of the epithelial mechanisms that underlie the pre-malignant gastric landscape, how Hp adapts to and exploits these changes, and the clinical implications of identifying these changes in order to stratify patients at risk of developing gastric cancer, a leading cause of cancer-related deaths worldwide.

Gastritis: The clinico-pathological spectrum

The inflammatory spectrum of gastric diseases includes different clinico-pathological entities, the etiology of which was recently established in the international Kyoto classification. A diagnosis of gastritis combines the information resulting form the gross examination (endoscopy) and histology (microscopy). It is important to consider the anatomical/functional heterogeneity of the gastric mucosa when obtaining representative mucosal biopsy samples. Gastritis includes self-limiting and non-self-limiting (long-standing) inflammatory diseases, and the latter are epidemiologically, biologically and clinically linked to the onset of gastric cancer (i.e. "inflammation-associated cancer"). Different biological models of inflammation-associated gastric oncogenesis have been proposed. Helicobacter pylori (H. pylori) gastritis is the most prevalent worldwide, and H. pylori is classified as a first-class carcinogen. On these bases, eradicating H. pylori is mandatory for the primary prevention of gastric cancer. Non-self-limiting gastritis may also be triggered by the immune-mediated destruction of gastric parietal cells, resulting in autoimmune gastritis. In both H. pylori-related and autoimmune gastritis, the non-self-limiting inflammation results in atrophy of the gastric mucosa, which is the main factor promoting gastric cancer. Long-term follow-up studies consistently demonstrate the prognostic impact of the histological staging of gastritis in gastric cancer secondary prevention strategies.

Intestinal Metaplasia of the "Cardia": Accurate Differentiation of Gastric or Esophageal Origin With an Expanded Biopsy Protocol

Whether intestinal metaplasia (IM) distal to the endoscopic gastroesophageal junction (GEJ), that is, the cardia, is gastric or esophageal or both is controversial. Biopsies from this region are believed to be unreliable in resolving this issue and are not recommended. Our objective was to develop an accurate method of histologic diagnosis for IM of the cardia. An expanded biopsy protocol was employed in 986 patients irrespective of indication for endoscopy. This sampled columnar lined esophagus (CLE) when present, the endoscopic GEJ defined by the proximal limit of rugal folds, the area 1 cm distal to the GEJ, and distal stomach. The prevalence and associations of IM in these 4 locations were evaluated. IM was found in 79/91 patients with CLE above the GEJ. This was significantly associated with IM at the GEJ in 40/79 patients (P<0.001). The biopsy taken distal to the endoscopic GEJ had IM in 21/79 patients. No patient with CLE had IM in the distal stomach. In patients without CLE, IM was present at or distal to the endoscopic GEJ in 221 patients. In 32 patients, this was significantly associated with IM in the distal stomach (P<0.001). The remaining 189/986 (19.2%) patients had IM limited to the GEJ region. These data, in association with recent evidence, indicate that IM limited to the area distal to the GEJ in patients without distal gastric IM represents microscopic Barrett esophagus in a dilated distal esophagus. This is presently mistaken for IM of the proximal stomach because of a flawed endoscopic definition of the GEJ.

Chronic High-Fat Diet Induces Early Barrett's Esophagus in Mice through Lipidome Remodeling

Esophageal adenocarcinoma (EAC) incidence has been rapidly increasing, potentially associated with the prevalence of the risk factors gastroesophageal reflux disease (GERD), obesity, high-fat diet (HFD), and the precursor condition Barrett’s esophagus (BE). EAC development occurs over several years, with stepwise changes of the squamous esophageal epithelium, through cardiac metaplasia, to BE, and then EAC. To establish the roles of GERD and HFD in initiating BE, we developed a dietary intervention model in C57/BL6 mice using experimental HFD and GERD (0.2% deoxycholic acid, DCA, in drinking water), and then analyzed the gastroesophageal junction tissue lipidome and microbiome to reveal potential mechanisms. Chronic (9 months) HFD alone induced esophageal inflammation and metaplasia, the first steps in BE/EAC pathogenesis. While 0.2% deoxycholic acid (DCA) alone had no effect on esophageal morphology, it synergized with HFD to increase inflammation severity and metaplasia length, potentially via increased microbiome diversity. Furthermore, we identify a tissue lipid signature for inflammation and metaplasia, which is characterized by elevated very-long-chain ceramides and reduced lysophospholipids. In summary, we report a non-transgenic mouse model, and a tissue lipid signature for early BE. Validation of the lipid signature in human patient cohorts could pave the way for specific dietary strategies to reduce the risk of BE in high-risk individuals.

Endoscopic features of esophageal adenocarcinoma derived from short-segment versus long-segment Barrett's esophagus

BACKGROUND AND AIM

The study aims to clarify the endoscopic features and clinicopathological differences in superficial Barret's esophageal adenocarcinoma (s-BEA) derived from short-segment Barrett's esophagus (SSBE) and long-segment Barrett's esophagus (LSBE).

METHODS

We reviewed data of 130 patients (141 lesions) with pathologically confirmed s-BEA (SSBE: 95 patients and 95 lesions; LSBE: 35 patients and 46 lesions). We analyzed endoscopic and clinicopathological features of s-BEA in patients with SSBE and LSBE.

RESULTS

The distribution of lesions according to macroscopic findings were as follows (s-BEA in SSBE vs LSBE): flat type (0-IIb), 3.2% (3/95) vs 32.6% (15/46) (P < 0.001); accompanied type 0-IIb, 2.1% (2/95) vs 21.7% (10/46) (P < 0.001); and complex type (0-I + IIb, 0-IIa + IIc, etc.), 30.5% (29/95) vs 50.0% (23/46) (P = 0.025). Complex-type s-BEAs had high incidences of T1b invasions and poorly differentiated components (simple type: 22.5% [20/89] and 18.0% [16/89]; complex type: 59.6% [31/52] and 44.2% [23/52], P < 0.001 and P = 0.002, respectively). In SSBE, 72.6% (69/95) of lesions were located at the right anterior wall (P = 0.01). All flat-type or depressed-type lesions derived from SSBE were identified as reddish areas, whereas only 65.2% (15/23) from LSBE were identified as reddish areas (P < 0.001).

CONCLUSIONS

In LSBE, flat-type, accompanied-type 0-IIb, and complex-type lesions were significantly more prevalent. Furthermore, complex-type s-BEAs tended to have T1b invasions and poorly differentiated components. S-BEAs in LSBE should be more carefully evaluated on endoscopic appearance including flat-type and complex-type lesions than in SSBE.

A region-resolved mucosa proteome of the human stomach

The human gastric mucosa is the most active layer of the stomach wall, involved in food digestion, metabolic processes and gastric carcinogenesis. Anatomically, the human stomach is divided into seven regions, but the protein basis for cellular specialization is not well understood. Here we present a global analysis of protein profiles of 82 apparently normal mucosa samples obtained from living individuals by endoscopic stomach biopsy. We identify 6,258 high-confidence proteins and estimate the ranges of protein expression in the seven stomach regions, presenting a region-resolved proteome reference map of the near normal, human stomach. Furthermore, we measure mucosa protein profiles of tumor and tumor nearby tissues (TNT) from 58 gastric cancer patients, enabling comparisons between tumor, TNT, and normal tissue. These datasets provide a rich resource for the gastrointestinal tract research community to investigate the molecular basis for region-specific functions in mucosa physiology and pathology including gastric cancer.

The human stomach is divided into seven anatomically distinct regions but their protein composition is largely unknown. Here, the authors present a region-resolved map of the healthy human stomach mucosa as well as mucosa proteomes of tumor and tumor nearby tissue from gastric cancer patients.

Carditis: a relevant marker of gastroesophageal reflux disease. Data from a prospective central European multicenter study on histological and endoscopic diagnosis of esophagitis (histoGERD trial)

The columnar-lined mucosa at the gastroesophageal junction may contain an inflammatory infiltrate, commonly referred to as carditis (or cardia gastritis). The etiology of carditis is not entirely clear since published data are conflicting. Some authors believe it to be secondary to gastroesophageal reflux disease (GERD) and others to Helicobacter pylori gastritis. This prospective study aims at clarifying the relationship between carditis and the histological, clinical, and endoscopic findings of GERD, in a large cohort of individuals negative for H. pylori infection. Eight hundred and seventy-three individuals (477 females and 396 males, median age 53 years) participated in this study. Biopsy material was systematically sampled from above and below the gastroesophageal junction. Reflux-associated changes of the esophageal squamous epithelium were assessed according to the Esohisto consensus guidelines. Grading of carditis was performed according to the Updated Sydney System, known from the histological evaluation of gastritis. In total, 590 individuals (67.5%) had chronic carditis. Of these, 468 (53.6%) had mild chronic inflammation, with 321 individuals (68.6%) showing no or minimal changes on endoscopic examination (Los Angeles Categories N and M). The presence of chronic carditis was associated with several GERD-related parameters of the esophageal squamous epithelium (P < 0.0001), and data retained statistical significance even when analysis was restricted to individuals with mild chronic carditis and/or endoscopically normal mucosa. Chronic carditis was also associated with the presence of intestinal metaplasia (P < 0.0001). In addition, chronic carditis had a statistically significant association with patients' symptoms of GERD (P = 0.0107). This observation remained valid for mild chronic carditis in all patients (P = 0.0038) and in those with mild chronic carditis and normal endoscopic mucosa (P = 0.0217). In conclusion, chronic carditis appears to be the immediate consequence of GERD, correlating with patients' symptoms and endoscopic diagnosis. These results are valid in individuals with nonerosive reflux disease, which indicates a higher sensitivity of histological diagnosis. Our findings may impact the routine assessment of reflux patients.

Origins of Metaplasia in the Esophagus: Is This a GE Junction Stem Cell Disease?

The incidence of esophageal adenocarcinoma (EAC) and its precursor lesion Barrett's esophagus (BE) has been increasing steadily in the western world in recent decades. Understanding the cellular origins of BE and the conditions responsible for their malignant transformation would greatly facilitate risk assessment and identification of patients at risk of progression, but this topic remains a source of debate. Here, we review recent findings that have provided support for the gastroesophageal junction (GEJ) as the main source of stem cells that give rise to BE and EAC. These include both gastric cardia cells and transitional basal cells. Furthermore, we discuss the role of chronic injury and inflammation in a tumor microenvironment as a major factor in promoting stem cell expansion and proliferation as well as transformation of the GEJ-derived stem cells and progression to EAC. We conclude that there exists a large amount of empirical support for the GEJ as the likely source of BE stem cells. While BE seems to resemble a successful adaptation to esophageal damage, carcinogenesis appears as a consequence of natural selection at the level of GEJ stem cells, and later glands, that expand into the esophagus wherein the local ecology creates the selective landscape for cancer progression.

How the pathologist can aid in the assessment of gastroesophageal reflux disease

PURPOSE OF REVIEW

To provide new concepts regarding the early pathologic changes of gastroesophageal reflux disease (GERD) that are associated with damage to the lower esophageal sphincter (LES).

RECENT FINDINGS

A body of evidence exists that cardiac mucosa is a metaplastic esophageal epithelium rather than a normal gastric epithelium. Recent studies in asymptomatic volunteers suggest a potential mechanism for cardiac metaplasia in the squamous epithelium of the esophagus.

SUMMARY

The concept that cardiac mucosa is esophageal, not gastric, suggests that the widely accepted endoscopic definition of the gastroesophageal junction (GEJ) is incorrect. I propose that the true GEJ is the proximal extent of gastric oxyntic epithelium. If there is cardiac mucosa lining proximal rugal folds, that cardiac mucosa-lined region is the dilated distal esophagus, not the proximal stomach. The dilated distal esophagus is the pathologic expression of damage to the abdominal segment of the LES. This concept suggests a new test for measuring damage to the abdominal LES and a new understanding of the disease of GERD based on the measured amount of LES damage. This opens the door to new research and change in objectives in the management of reflux disease from control of symptoms to prevention of complications such as Barrett's esophagus and adenocarcinoma.

Acid and the basis for cellular plasticity and reprogramming in gastric repair and cancer

Subjected to countless daily injuries, the stomach still functions as a remarkably efficient digestive organ and microbial filter. In this Review, we follow the lead of the earliest gastroenterologists who were fascinated by the antiseptic and digestive powers of gastric secretions. We propose that it is easiest to understand how the stomach responds to injury by stressing the central role of the most important gastric secretion, acid. The stomach follows two basic patterns of adaptation. The superficial response is a pattern whereby the surface epithelial cells migrate and rapidly proliferate to repair erosions induced by acid or other irritants. The stomach can also adapt through a glandular response when the source of acid is lost or compromised (that is, the process of oxyntic atrophy). We primarily review the mechanisms governing the glandular response, which is characterized by a metaplastic change in cellular differentiation known as spasmolytic polypeptide-expressing metaplasia (SPEM). We propose that the stomach, like other organs, exhibits marked cellular plasticity: the glandular response involves reprogramming mature cells to serve as auxiliary stem cells that replace lost cells. Unfortunately, such plasticity might mean that the gastric epithelium undergoes cycles of differentiation and de-differentiation that increase the risk of accumulating cancer-predisposing mutations.

Combined Extensive Esophageal Squamous Papillomas and Florid Cardiac Gland Hyperplasia in a Patient with Adenocarcinoma

We report a rare case of extensive esophageal squamous papillomas (ESPs) involving the entire esophagus and florid cardiac gland hyperplasia involving only the lower esophagus in a 39-year-old woman with heartburn and epigastric distress for the past 2 years. Previous esophagogastroduodenoscopy showed multiple ESPs involving the entire esophagus extending 38 cm from the esophageal orifice to the esophagogastric junction (EGJ). Additionally, prominent cardiac gland hyperplasia over the esophageal posterior wall was exhibited extending 12 cm from the mid-esophagus to the EGJ. A biopsy obtained from the ESP area showed typical squamous papillomas and cardiac gland hyperplasia with no evidence of koilocytosis or malignancy. Polymerase chain reaction was negative for a variety of human papilloma virus DNAs. Subsequently, Siewert type II gastric cancer with submucosal elevation of the stomach was detected at the EGJ. Endoscopy showed a 20-mm-thick lesion appearing to extend to the muscularis propria; subsequent biopsy showed invasive adenocarcinoma. Total gastrectomy with D2 lymph node dissection, splenectomy, and Roux-en-Y reconstruction were performed for the EGJ cancer. The patient died from widespread multiorgan metastasis within 2 years following surgery.

Endoscopic mucosal ablation and resection of Barrett's esophagus and related diseases

The prevalence of gastroesophageal reflux disease as well as the incidence of Barrett's esophagus (BE) has increased in the Western world over the last decades. The chronic reflux of gastric secretions injuries the esophageal mucosa and triggers cellular and molecular changes inducing the transformation of the normal squamous mucosa into columnar metaplastic epithelium. BE is a premalignant condition that can progress to low-grade dysplasia, high-grade dysplasia and ultimately esophageal adenocarcinoma. An early diagnosis of dysplastic changes and the adoption of appropriate therapeutic approaches are essential to improve patient outcomes and survival. Endoscopic therapies such as radiofrequency ablation (RFA) and endoscopic mucosal resection (EMR) have been developed to treat dysplastic changes and mucosal abnormalities suspicious of malignancy. RFA has shown to be safe and effective for the treatment of low and high-grade dysplasia. EMR is diagnostic for mucosal lesions and potentially therapeutic for high-grade dysplasia or intramucosal adenocarcinoma. Proficient endoscopic skills and frequent practice are essential elements for a successful result. Here, we describe patient selection, the pre- and post-operative management, and the surgical technique for RFA and EMR in patients with the diagnosis of dysplastic BE and intramucosal esophageal adenocarcinoma.

Optimizing the diagnosis and therapy of Barrett's esophagus

The incidence of Barrett's esophagus (BE) in the Western world has increased over the last decades. BE is considered a premalignant lesion that can progress to esophageal adenocarcinoma (EAC), a highly aggressive malignancy with poor survival rates. The close association between BE and EAC highlights the need for an early diagnosis in order to improve survival and outcomes in this group of patients. Although the evidence for BE screening with conventional endoscopy is controversial and limited by cost-effectiveness studies, screening can be suggested in patients with chronic gastroesophageal reflux disease (GERD) and two or more risk factors for EAC. Less invasive techniques with lower costs and higher acceptability by the patients may be useful for screening in the general population. Several novel techniques have been described to aid in the early diagnosis and management of BE and dysplasia. However, these techniques have shown variable results with higher costs, the need of specific training, and variable inter-observer imaging interpretation, making its widespread implementation problematic. High-definition/high-resolution white-light endoscopy (WLE) continues to be a well-accepted technique for the evaluation and surveillance of patients with BE. Further studies are required in order to establish the efficacy of less invasive methods that can be performed in an outpatient setting for BE screening in higher risk individuals.

Intestinal Metaplasia is Present in Most if Not All Patients Who Have Undergone Endoscopic Mucosal Resection for Esophageal Adenocarcinoma

Barrett esophagus is presently defined in the United States by the presence of intestinal metaplasia in columnar-lined esophagus based on the premise that the risk for adenocarcinoma depends on the presence of intestinal metaplasia. Recently, arguments have been made that nonintestinalized cardiac epithelium is also at risk and should be included in the definition of Barrett esophagus, as it is in England and Japan. One of these arguments is that residual intestinal metaplasia is frequently absent around early adenocarcinomas removed by endoscopic mucosal resection (EMR). We reviewed 27 EMRs performed in 21 patients. Residual intestinal metaplasia was absent in 10/27 (37%) EMR specimens. An in-depth study of these 10 cases showed that 3 had intestinal metaplasia in a concurrent second EMR specimen, 4 had intestinal metaplasia in prior biopsy material available in our unit, and 2 had intestinal metaplasia in an esophagectomy that followed the EMR. The single patient in whom no intestinal metaplasia was found, neither in biopsies nor in EMR, and who did not undergo an esophagectomy had been under surveillance for Barrett esophagus for over 20 years. We conclude that the frequent absence of residual intestinal metaplasia around an adenocarcinoma in an EMR specimen is the result of sampling error. When evaluated in depth by looking at history, biopsies preceding the EMR, and esophagectomy following the EMR, all of these patients with adenocarcinoma had intestinal metaplasia in their columnar-lined esophagus. This indicates that intestinal metaplasia is a necessary precursor to adenocarcinoma of the esophagus.

In healthy volunteers, immunohistochemistry supports squamous to columnar metaplasia as mechanism of expansion of cardia, aggravated by central obesity

INTRODUCTION

Recently, we showed that the length of cardiac mucosa in healthy volunteers correlated with age and obesity. We have now examined the immunohistological characteristics of this expanded cardia to determine whether it may be due to columnar metaplasia of the distal oesophagus.

METHODS

We used the squamocolumnar junction (SCJ), antral and body biopsies from the 52 Helicobacter pylori-negative healthy volunteers who had participated in our earlier physiological study and did not have hiatus hernia, transsphincteric acid reflux, Barrett's oesophagus or intestinal metaplasia (IM) at cardia. The densities of inflammatory cells and reactive atypia were scored at squamous, cardiac and oxyntocardiac mucosa of SCJ, antrum and body. Slides were stained for caudal type homeobox 2 (CDX-2), villin, trefoil factor family 3 (TFF-3) and liver-intestine (LI)-cadherin, mucin MUC1, Muc-2 and Muc-5ac. In addition, biopsies from 15 Barrett's patients with/without IM were stained and scored as comparison. Immunohistological characteristics were correlated with parameters of obesity and high-resolution pH metry recording.

RESULTS

Cardiac mucosa had a similar intensity of inflammatory infiltrate to non-IM Barrett's and greater than any of the other upper GI mucosae. The immunostaining pattern of cardiac mucosa most closely resembled non-IM Barrett's showing only slightly weaker CDX-2 immunostaining. In distal oesophageal squamous mucosa, expression of markers of columnar differentiation (TFF-3 and LI-cadherin) was apparent and these correlated with central obesity (correlation coefficient (CC)=0.604, p=0.001 and CC=0.462, p=0.002, respectively). In addition, expression of TFF-3 in distal oesophageal squamous mucosa correlated with proximal extension of gastric acidity within the region of the lower oesophageal sphincter (CC=-0.538, p=0.001).

CONCLUSIONS

These findings are consistent with expansion of cardia in healthy volunteers occurring by squamo columnar metaplasia of distal oesophagus and aggravated by central obesity. This metaplastic origin of expanded cardia may be relevant to the substantial proportion of cardia adenocarcinomas unattributable to H. pylori or transsphincteric acid reflux.

Barrett's esophagus: recent insights into pathogenesis and cellular ontogeny

Esophageal adenocarcinoma (EAC) has increased 6-fold in its incidence in the last 2 decades. Evidence supports the hypothesis of stepwise progression from normal squamous epithelium → reflux esophagitis → metaplasia (Barrett's esophagus, BE) → dysplasia → adenocarcinoma. The precursor, BE, stands as the bridge connecting the widespread but naive reflux disease and the rare but fatal EAC. The step of metaplasia from squamous to intestine-like columnar phenotype is perhaps pivotal in promoting dysplastic vulnerability. It is widely accepted that chronic inflammation because of gastroesophageal reflux disease leads to the development of metaplasia, however the precise molecular mechanism is yet to be discovered. Additionally, how this seemingly adaptive change in the cellular phenotype promotes dysplasia remains a mystery. This conceptual void is deterring further translational research and clouding clinical decision making. This article critically reviews theories on the pathogenesis of Barrett's esophagus and the various controversies surrounding its diagnosis. We further discuss unanswered questions and future directions, which are vital in formulating effective preventive and therapeutic guidelines for Barrett's esophagus.

Gastric acid secretion: changes during a century

The advances in knowledge of gastric physiology within the past century have been the most exciting and important in this area of interest for many decades. The aim of this presentation consists of a comprehensive review of the extensive recent literature on this topic in order to highlight milestones in the field of gastric physiology, in particular in gastric acid secretion, gastric pathophysiology, acid-related diseases and use of acid regulatory drugs. Moreover, in the 21st century there have been many epidemiologic changes as well as a decrease of Helicobacter pylori infection and gastric cancer together with an increase of gastroesophageal reflux disease and the related increase of pomp proton inhibitor wide use.

Etiology and morphology of carditis: experiences from a single center in China

OBJECTIVE

To investigate the type of cardiac mucosa and its relationship with age and gender of the participants and to determine the coincidence of endoscopic and pathological diagnosis of carditis as well as its etiology.

METHODS

The data of 70 patients with carditis (the carditis group) and 30 individuals with endoscopically normal-appearing cardiac mucosa (the control group), including their baseline characteristics and histopathological findings, were reviewed. Their Helicobacter pylori (H. pylori) status was also reviewed.

RESULTS

Three main types of cardiac mucosa: mucous, oxyntic and mixed types, were found in 45.0%, 40.0% and 15.0% of all the participants, respectively. The distribution of these types was related to the age of the participants but not to their gender. Moderate to severe mucosal inflammation was detected in 60.0% (18/30) of the control group. The etiologies of cardiac inflammation were H. pylori infection and gastroesophageal reflux disease (GERD). For antral H. pylori-negative participants, cardiac mucosal inflammation was correlated with esophageal mucosal inflammation (P < 0.05), while for those with antral H. pylori infection it was associated with antral mucosal inflammation (P < 0.01).

CONCLUSIONS

The distribution of different cardiac mucosal types was related to the participants' age. Normal-appearing cardiac mucosa under endoscopy might present with histopathologically moderate to severe cardiac inflammation. The etiologies of cardiac inflammation were H. pylori infection and GERD. Different causes of carditis may result in the different histological performance of the cardia.

Central obesity in asymptomatic volunteers is associated with increased intrasphincteric acid reflux and lengthening of the cardiac mucosa

BACKGROUND & AIMS

In the West, a substantial proportion of subjects with adenocarcinoma of the gastric cardia and gastroesophageal junction have no history of reflux. We studied the gastroesophageal junction in asymptomatic volunteers with normal and large waist circumferences (WCs) to determine if central obesity is associated with abnormalities that might predispose individuals to adenocarcinoma.

METHODS

We performed a study of 24 healthy, Helicobacter pylori-negative volunteers with a small WC and 27 with a large WC. Abdominal fat was quantified by magnetic resonance imaging. Jumbo biopsy specimens were taken across the squamocolumnar junction (SCJ). High-resolution pH-metry (12 sensors) and manometry (36 sensors) were performed in upright and supine subjects before and after a meal; the SCJ was visualized fluoroscopically.

RESULTS

The cardiac mucosa was significantly longer in the large WC group (2.5 vs 1.75 mm; P = .008); its length correlated with intra-abdominal (R = 0.35; P = .045) and total abdominal (R = 0.37; P = .034) fat. The SCJ was closer to the upper border of the lower esophageal sphincter (LES) in subjects with a large WC (2.77 vs 3.54 cm; P = .02). There was no evidence of excessive reflux 5 cm above the LES in either group. Gastric acidity extended more proximally within the LES in the large WC group, compared with the upper border (2.65 vs 4.1 cm; P = .027) and peak LES pressure (0.1 cm proximal vs 2.1 cm distal; P = .007). The large WC group had shortening of the LES, attributable to loss of the distal component (total LES length, 3 vs 4.5 cm; P = .043).

CONCLUSIONS

Central obesity is associated with intrasphincteric extension of gastric acid and cardiac mucosal lengthening. The latter might arise through metaplasia of the most distal esophageal squamous epithelium and this process might predispose individuals to adenocarcinoma.

Pancreatic acinar cells--a normal finding at the gastroesophageal junction? Data from a prospective Central European multicenter study

Pancreatic acinar cells are a well-recognized finding at the gastroesophageal junction, but their histogenesis and biological significance are unclear. From the prospective Central European multicenter histoGERD trial, we recruited 1,071 individuals undergoing gastroscopy for various non-selected reasons. Biopsy material was systematically sampled from the gastroesophageal junction and from the stomach. The study aimed to assess the prevalence of pancreatic acinar cells and to relate their presence to various histologic and clinical features. Overall, pancreatic acinar cells were observed in 184 (17.2%) participants. Individuals diagnosed with pancreatic acinar cells were slightly younger than those without (median 50 vs. 53 years; p = 0.009). There was no association with patients' symptoms and/or complaints or with an endoscopic diagnosis of esophagitis or Barrett's esophagus. Regarding histology, pancreatic acinar cells were not associated with features of the squamous epithelium indicating reflux disease, such as basal cell hyperplasia, papillary elongation, dilation of intercellular spaces, and inflammatory cell number, but were associated with the presence of cardiac mucosa (p < 0.001), oxyntocardiac mucosa (p < 0.001), and intestinal metaplasia (p = 0.038), respectively. No association with Helicobacter pylori infection or diagnosis of gastritis was noted. In conclusion, pancreatic acinar cells are a common finding at the gastroesophageal junction, and no association with either reflux disease (histologically or endoscopically) or diagnosis of gastritis was observed. These data suggest a congenital rather than an acquired (metaplastic) origin of pancreatic acinar cells at the gastroesophageal junction. This questions the term "pancreatic acinar metaplasia" which is currently widely used for their diagnosis.

Histologic definition of gastro-esophageal reflux disease

PURPOSE OF REVIEW

To review recent data supporting the development of new histology-based definitions of gastro-esophageal reflux disease (GERD).

RECENT FINDINGS

Three precisely definable columnar epithelial types--cardiac, oxyntocardiac and intestinal--may be interposed between esophageal squamous epithelium and gastric oxyntic (acid secreting) mucosa. This enables definition of a new histologic concept: the squamo-oxyntic gap. The squamo-oxyntic gap is zero or very small in autopsies performed on patients without evidence of GERD. The gap progressively increases in length with the severity of GERD, indicating that the squamo-oxyntic gap is a marker for chronic GERD. The distal part of the gap lines gastric-type rugal folds and, therefore, is distal to the present endoscopic definition of the gastro-esophageal junction. I contend that this distal gap segment (which has esophageal submucosal glands) is actually the dilated distal esophagus; this is the pathologic correlate of destruction of the abdominal segment of the lower esophageal sphincter. The dilated distal esophagus is mistaken for 'gastric cardia' by present endoscopic definitions.

SUMMARY

I believe that these data support the adoption of novel histologic definitions of GERD as follows: the presence of any squamo-oxyntic gap defines GERD; the length of the gap is a measure of severity of chronic GERD; and the presence of intestinal metaplasia in the gap defines Barrett esophagus and cancer risk.

Preoperative assessment of tumor location and station-specific lymph node status in patients with adenocarcinoma of the gastroesophageal junction

BACKGROUND

In esophageal cancer patients preoperative staging will determine the type of surgical procedure and use of neoadjuvant therapy. Tumor location and lymph node status play a pivotal role in this tailored strategy. The aim of the present study was to prospectively evaluate the accuracy of preoperative assessment of tumor location according to the Siewert classification and lymph node status per station with endoscopy/endoscopic ultrasound (EUS) and computed tomography (CT).

METHODS

In 50 esophagectomy patients with adenocarcinoma of the gastroesophageal junction (GEJ), tumor location according to Siewert and N-stage per nodal station as determined preoperatively by endoscopy/EUS and CT were compared with the histopathologic findings in the resection specimen.

RESULTS

Overall accuracy in predicting tumor location according to the Siewert classification was 70 % for endoscopy/EUS and 72 % for CT. Preoperative data could not be compared with the pathologic assessment in 11 patients (22 %), as large tumors obscured the landmark of the gastric folds. The overall accuracy for predicting the N-stage in 250 lymph node stations was 66 % for EUS and 68 % for CT. The accuracy was good for those stations located high in the thorax, but poor for celiac trunk nodes.

CONCLUSIONS

Given the frequent discrepancy between the endoscopic and pathologic location of the GEJ and the common problem of advanced tumors obscuring the landmarks used in the assessment of the Siewert classification, its usefulness is limited. The overall accuracy for EUS and CT in predicting the N-stage per station was moderate.

Erosive reflux disease increases risk for esophageal adenocarcinoma, compared with nonerosive reflux

BACKGROUND & AIMS

Gastroesophageal reflux disease is a strong risk factor for esophageal adenocarcinoma, but it is not clear whether the mucosal inflammation that develops in patients with reflux disease promotes this cancer. We determined the development of adenocarcinoma among patients who underwent esophagogastroduodenoscopy and were found to have erosive (with esophagitis) or nonerosive (without esophagitis) reflux.

METHODS

We performed a nationwide cohort study using data from 33,849 patients with reflux disease (52% men; median age, 59.3 y) from population-based Danish medical registries, from 1996 through 2008. The observed incidences of adenocarcinoma were compared with the expected incidence for the general population, standardized by age, sex, and calendar time. Absolute risks were estimated using Kaplan-Meier methods.

RESULTS

In the study cohort, 26,194 of the patients (77%) had erosive reflux disease and 37 subsequently developed esophageal adenocarcinoma after a mean follow-up time of 7.4 years. Their absolute risk after 10 years was 0.24% (95% confidence interval [CI], 0.15%-0.32%). The incidence of cancer among patients with erosive reflux disease was significantly greater than that expected for the general population (standardized incidence ratio, 2.2; 95% CI, 1.6-3.0). In contrast, of the 7655 patients with nonerosive reflux disease, only 1 was diagnosed with esophageal adenocarcinoma after 4.5 years of follow-up evaluation (standardized incidence ratio, 0.3; 95% CI, 0.01-1.5).

CONCLUSIONS

Erosive reflux disease, but not nonerosive disease, increased the risk of esophageal adenocarcinoma, based on analysis of population-based Danish medical registries. Inflammation therefore might be an important factor in the progression from reflux to esophageal 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.

Columnar-lined esophagus without intestinal metaplasia has no proven risk of adenocarcinoma

Intestinal metaplasia in the columnar-lined esophagus (CLE) has long been recognized as the most significant histologic risk indicator for esophageal adenocarcinoma. Recent concern has been expressed, however, that nonintestinalized metaplastic columnar epithelia (cardiac epithelium in the esophagus) may also indicate risk. Of 2586 consecutive patients undergoing endoscopy and biopsy in the Foregut Surgery Department, we selected (a) 214 patients with a visible CLE who had systemic 4-quadrant biopsies at 1 to 2 cm intervals, with the most proximal biopsy straddling the squamocolumnar junction, and (b) 109 patients without systematic biopsy who had dysplasia or adenocarcinoma. In the first group, 187 (87.4%) patients had intestinal metaplasia, and 27 (12.6%) had cardiac epithelium. Dysplasia or adenocarcinoma was present in 55 patients, all with intestinal metaplasia; its presence was significantly higher than in the cardiac epithelium group, none of whom had dysplasia or adenocarcinoma (P=0.01). In the second group with limited sampling, 49 had only tumor tissue in the biopsy. Of 60 patients with nontumor epithelium, only 34 (56.7%) had residual intestinal metaplasia. We conclude that systematic biopsies of CLE as described in this study separate patients into those with and without intestinal metaplasia in such a manner as to remove the possibility of false-negative diagnosis of intestinal metaplasia. When intestinal metaplasia is absent using this biopsy protocol, the patient is at no or extremely low risk for dysplasia and cancer. When biopsies have a lower level of sampling of the segment of CLE, the absence of intestinal metaplasia cannot be interpreted as a true negative for intestinal metaplasia. Inadequate sampling is a powerful reason why the near absolute association between intestinal metaplasia and adenocarcinoma is not seen in some studies.

The dilated distal esophagus: a new entity that is the pathologic basis of early gastroesophageal reflux disease

Present management algorithms for patients with gastroesophageal reflux disease (GERD) limit endoscopy to patients with advanced disease. When endoscopy is performed, biopsy is limited to patients who have a visible columnar-lined esophagus. Biopsy is not recommended for patients whose endoscopy is normal. This algorithm results in the failure to evaluate patients with early stages of GERD at a pathologic level. We report 714 patients with normal endoscopic findings irrespective of symptoms who had adequate biopsies taken from the squamocolumnar junction and the area 1-cm distal to this from mucosa that had rugal folds. Concurrent biopsies were also taken from the gastric body and/or antrum. All patients had a gap between their esophageal squamous epithelium and gastric oxyntic mucosa in the junctional region composed of oxyntocardiac ± cardiac ± intestinal epithelia. A total of 643 (90.1%) patients had no significant pathology in the gastric antrum and/or body, indicating that the squamooxyntic gap was an isolated abnormality in this region in all but 71 (9.9%) patients. The gap contained only oxyntocardiac epithelium in 71 (9.9%) patients, cardiac mucosa without intestinal metaplasia in 482 (67.5%) patients, and intestinal metaplasia in 161 (22.6%) patients. The pathologic interpretation of biopsies taken from the gastroesophageal junction is confusing and has significant interobserver variation. This results from lack of agreement as to whether these biopsies originate in the proximal stomach ("gastric cardia") or in the esophagus. We provide evidence that the presence of oxyntocardiac ± cardiac ± intestinal epithelia in biopsies from patients who are endoscopically normal is diagnostic of a dilated GERD-damaged distal esophagus. The dilated distal esophagus is the pathologic manifestation of destruction of the abdominal segment of the lower esophageal sphincter. Its presence is the pathologic basis of early GERD, which is missed if patients who are endoscopically normal are not biopsied, as is the present recommendation. Its recognition allows for accurate and evidence-based interpretation of biopsies from this region and removes the present confusion and permits the development of a reproducible pathologic diagnostic method.

Controversies of cardiac glands in the proximal stomach: a critical review

Cardiac glands (CG), along with oxyntocardiac glands, in a normal human constitute cardiac mucosa (CM) that is positioned in the proximal stomach with a length of 10-30 mm, according to traditional teaching. This doctrine has been recently challenged. On the basis of studies on autopsy and biopsy materials in the esophagogastric junction region, some investigators have reported the presence of CG in only 50% of the general US population. They believed that CG were an acquired, metaplastic lesion as a result of gastroesophageal reflux disease. Subsequent recent study results from other research groups showed the presence of CG in the proximal stomach in embryos, fetuses, pediatric, and adult patients in most Europeans and Americans, and almost all Japanese and Chinese patients. These new data showed the following important findings: (i) CG are confirmed to be congenital in the proximal stomach; (ii) the length of CM is much shorter, approximately 5 mm in Caucasians in Europe and North America, and approximately 13 mm in Japanese and probably also in Chinese; (iii) CG are also present in the distal superficial esophagus underneath squamous mucosa in almost all Japanese and Chinese patients, but not so common in Caucasians in Europe, and not clear in Caucasians in North America. The recent data indicate a clear difference in the distribution of CG in the proximal stomach among different ethnic populations, and might explain different disease pathogenesis mechanisms among various ethnic patient groups.

The histologic squamo-oxyntic gap: an accurate and reproducible diagnostic marker of gastroesophageal reflux disease

The present definition of gastroesophageal reflux disease (GERD) is based on clinical criteria that are difficult to reproduce accurately. This study provides a method to develop a histologic definition of GERD based on biopsies obtained from the affected esophagus. Pathology reports from 1655 patients who had upper gastrointestinal endoscopy and biopsy according to a systematic protocol were reviewed. Biopsies were obtained from the esophagus, around the gastroesophageal junction and the stomach: proximal, body, and antrum. Patients who had oxyntocardiac±cardiac±intestinal epithelia between the squamous epithelium proximally and the proximal limit of gastric oxyntic mucosa distally were defined as having a squamo-oxyntic gap. The length of the squamo-oxyntic gap varied from less than 1 cm in 1399 (84.5%) patients to greater than 5 cm in 80 (4.8%) of the patients. Only oxyntocardiac epithelium was seen in 190 (11.5%) of the patients, oxyntocardiac and cardiac epithelia in 898 (54.3%), and intestinal metaplasia in addition to the other 2 epithelial types in 567 (34.2%). The prevalence of intestinal metaplasia was directly proportional to length of the squamo-oxyntic gap, being 24.3% (340/1399) when the length was <1 cm, and 83.5% (147/176) with length 1 to 5 cm. All patients with a length more than 5 cm had intestinal metaplasia. The distribution of the 3 epithelia was constant irrespective of the length of the squamocolumnar gap; intestinal metaplasia, when present, was seen maximally in the proximal region of the gap, cardiac epithelium intermediate and oxyntocardiac epithelium in the most distal segment of the gap. The squamo-oxyntic gap started in a dilated region distal to the end of the tubular esophagus and distal to the proximal limit of the rugal folds and extended into the tubular esophagus. Distal gastric biopsies showed no evidence of significant inflammation, intestinal metaplasia or Helicobacter pylori infection in 1543 (93.2%) of the patients, indicating that the squamo-oxyntic gap was largely independent of gastric pathology. We provide evidence that the squamo-oxyntic gap is equivalent to the columnar-lined esophagus. Its presence is a specific and sensitive indicator of reflux and can be used as a cellular criterion to define GERD. The length of the squamo-oxyntic gap provides an accurate assessment of the severity of chronic GERD. The distal limit of the squamo-oxyntic gap, which is the junction between oxyntocardiac and gastric oxyntic epithelium is the true gastroesophageal junction. The presence of intestinal metaplasia within the squamo-oxyntic gap is the most accurate risk indicator for esophageal adenocarcinoma and defines Barrett esophagus.

Non-erosive reflux disease rather than cervical inlet patch involves globus

BACKGROUND

Gastroesophageal reflux is the most favored etiology for globus; however, recent studies suggest that a cervical inlet patch (heterotopic gastric mucosa in the cervical esophagus) involves globus. This study aimed to reveal whether these two conditions were associated with globus.

METHODS

A prospective cross-sectional survey was conducted for 2116 consecutive patients who underwent esophagogastroduodenoscopy in our hospital. Patients were interviewed about globus sensations and reflux symptoms prior to endoscopy. Non-erosive reflux disease was considered with reflux symptoms without reflux esophagitis. Inlet patch was detected using narrow-band imaging.

RESULTS

Sixty-three patients were excluded, and of the remaining 2053 patients (1117 male, 61 years old on average), 120 (5.8%) and 284 (13.8%) had globus and inlet patch, respectively. Multivariate analysis (n = 1584) following the exclusion of proton pump inhibitor users revealed that female gender, younger age (<60), inlet patch, and reflux symptoms were independent risk factors for the development of globus; however, reflux esophagitis was an independent factor for reducing the development of globus. In a reanalysis of non-erosive reflux disease instead of reflux symptoms, inlet patch and non-erosive reflux disease were independent risk factors for the development of globus (odds ratio, 2.9 and 12.1, respectively).

CONCLUSIONS

Non-erosive reflux disease was more closely associated with globus than an inlet patch. Our controversial results indicating a strong association of globus with non-erosive reflux disease and an inverse association of globus with reflux esophagitis may suggest that mechanisms other than gastroesophageal reflux as the etiology, such as an esophageal visceral hypersensitivity, involve globus.

Association of adenocarcinomas of the distal esophagus, "gastroesophageal junction," and "gastric cardia" with gastric pathology

Controversy exists as to whether adenocarcinomas occurring in the gastroesophageal junctional region and gastric cardia originate in the esophagus or the stomach. Esophageal adenocarcinoma is known to be strongly associated with gastroesophageal reflux disease; gastric adenocarcinoma with Helicobacter pylori gastritis, and gastric intestinal metaplasia. This study evaluates the association of these tumors with pathologic findings in the biopsies of the gastric body and the antrum. It is hypothesized that if these malignancies are esophageal, they should have little or no significant association with gastric pathology; if they are gastric, these patients should have a high prevalence of gastric pathology. Between 2004 and 2008, 234 patients were diagnosed with high-grade dysplasia (HGD) and/or adenocarcinoma; 107 were distal esophageal, 79 straddled the distal end of the tubular esophagus, and 48 were in the "gastric cardia." Simultaneous biopsies of the distal body and antrum were present in 185 patients; 49 had biopsy of either antrum or body. Gastric biopsies were assessed for inflammation, H. pylori infection, and intestinal metaplasia. During this period, 2146 patients had nonmalignant columnar epithelia in the esophagus with similar assessment of the stomach; these acted as a control group. The gastric biopsy was normal in 201/234 (85.9%) patients and showed significant inflammation, H. pylori infection, and/or gastric intestinal metaplasia in 33/234 (14.1%) patients. There was no gastritis, H. pylori infection, or intestinal metaplasia in 88/107 (82.2%) of the patients with distal esophageal HGD and/or adenocarcinoma, 70/79 (88.6%) with junctional HGD and/or adenocarcinoma, and 43/48 (85.9%) with "gastric cardiac" HGD and/or adenocarcinoma. The incidence of gastritis was significantly higher in the patients with HGD and/or adenocarcinoma (33/234 or 14.1%) than in the control population (146/2146 or 9.0%; P=0.01). This difference was largely the result of a higher incidence of gastritis in patients with HGD and/or adenocarcinoma in the distal third of the esophagus (19/107 or 17.8%) versus the control population (146/2146 or 9.0%; P=0.01). The incidence of H. pylori positivity was also significantly higher in the patients with HGD and/or adenocarcinoma in the distal third of the esophagus (13/107 or 12.2%) than in the control population (117/2146 or 5.5%; P=0.01). There was no significant difference between the control group and the patients with junctional and gastric cardiac HGD and/or adenocarcinoma for gastritis, H. pylori infection, or the gastric intestinal metaplasia. The absence of gastritis, H. pylori, and the gastric intestinal metaplasia in 85.9% of the patients with HGD and/or adenocarcinoma of the gastroesophageal junctional region strongly suggest that most of these originate in the esophagus. In the small minority of patients whose HGD and/or adenocarcinoma were associated with gastric pathology, the incidence of gastritis and H. pylori infection was significantly higher in patients with HGD and/or adenocarcinoma in the distal third of the esophagus and not in the junctional and "gastric cardiac" tumors. This suggests that the reflux of the gastric juice whose composition has been altered by gastritis and H. pylori infection may be associated with an increased tendency to HGD and/or adenocarcinoma in the distal third of the esophagus.

Pathophysiology and treatment of Barrett’s esophagus

Gastroesophageal reflux disease (GERD) affects an estimated 20% of the population in the United States. About 10%-15% of patients with GERD develop Barrett’s esophagus, which can progress to adenocarcinoma, currently the most prevalent type of esophageal cancer. The esophagus is normally lined by squamous mucosa, therefore, it is clear that for adenocarcinoma to develop, there must be a sequence of events that result in transformation of the normal squamous mucosa into columnar epithelium. This sequence begins with gastroesophageal reflux, and with continued injury metaplastic columnar epithelium develops. This article reviews the pathophysiology of Barrett’s esophagus and implications for its treatment. The effect of medical and surgical therapy of Barrett’s esophagus is compared.

The role of Cdx2 in Barrett's metaplasia

Metaplasia (or transdifferentiation) is defined as the transformation of one tissue type to another. Clues to the molecular mechanisms that control the development of metaplasia are implied from knowledge of the transcription factors that specify tissue identity during normal embryonic development. Barrett's metaplasia describes the development of a columnar/intestinal phenotype in the squamous oesophageal epithelium and is the major risk factor for oesophageal adenocarcinoma. This particular type of cancer has a rapidly rising incidence and a dismal prognosis. The homoeotic transcription factor Cdx2 (Caudal-type homeobox 2) has been implicated as a master switch gene for intestine and therefore for Barrett's metaplasia. Normally, Cdx2 expression is restricted to the epithelium of the small and large intestine. Loss of Cdx2 function, or conditional deletion in the intestine, results in replacement of intestinal cells with a stratified squamous phenotype. In addition, Cdx2 is sufficient to provoke intestinal metaplasia in the stomach. In the present paper, we review the evidence for the role of Cdx2 in the development of Barrett's metaplasia.

No parietal cell hypertrophy of the metaplastic corpus mucosa in the distal esophagus under PPI treatment

When biopsies obtained from short tongues of columnar epithelium in the distal esophagus show only corpus or cardia-corpus transitional mucosa, it remains uncertain whether we are dealing with columnar epithelium metaplasia or a sampling error. In 50 patients with gastro-esophageal reflux disease receiving proton pump inhibitor (PPI) with such tongues of columnar epithelium, we noted that under this treatment, PPI-typical hypertrophy of the parietal cells in the corpus can be found, but not in the corpus or cardia/corpus transitional mucosa in biopsy material obtained from tongues of columnar epithelium in the distal esophagus. These observations may by an indication that in short segments of columnar epithelium corpus, mucosa with no PPI-induced hyperplasia of the parietal cells may be interpreted as metaplastic mucosa.

Grading of gastric foveolar-type dysplasia in Barrett's esophagus

Dysplasia is the gold standard biomarker of cancer risk in Barrett's esophagus, but its diagnosis remains difficult. This is due in part to its multitude of histological appearances. One aspect receiving little attention concerns gastric-type Barrett's dysplasia, which is distinctly different from the well-established intestinal variant. Recognition of gastric-type dysplasia and development of separate grading criteria are required. The prevalence, diagnostic criteria, and natural history of gastric-type Barrett's dysplasia were systematically evaluated in 1854 endoscopic biopsies from a cohort of 200 consecutive Barrett's dysplasia patients. Goblet cells were present in all cases, confirming the utility of this defining feature of Barrett's esophagus. The prevalence of Barrett's gastric-type dysplasia was 15% at the patient level (30 of 200 patients) and 20% at the biopsy level (166 of 852 dysplastic biopsies). Gastric-type dysplasia uniformly showed non-stratified, basally oriented nuclei as the major criterion for distinguishing it from intestinal-type Barrett's dysplasia. As such, loss of nuclear polarity, as the most objective criterion to distinguish intestinal-type low- and high-grade dysplasia, cannot be applied to gastric-type dysplasia. Rather, discriminatory features included increased nuclear size with a high-grade dysplasia cutoff by receiver operating characteristic (ROC) analysis approximating 3-4 times the size of a mature lymphocyte, providing an optimal sensitivity, specificity, and area under the curve of 0.78, 0.90, and 0.90 (95% CI: (0.87, 0.93)), respectively. Crowded, irregular glandular architecture (P<0.001) was more common in high-grade lesions (P<0.001), as was eosinophilic and oncocytic cytoplasm relative to the mucinous cytoplasm (P<0.001), prominent nucleoli (P<0.001), mild nuclear pleomorphism (P<0.001), and villiform architecture (P<0.001). During follow-up, 64% (7 of 11) of patients with pure gastric and 26% (5 of 19) with mixed gastric and intestinal dysplasia underwent neoplastic progression. The recognition of Barrett's gastric-type dysplasia and use of the proposed grading criteria should promote better diagnostic classification of the Barrett's neoplastic spectrum.

Histology of metaplasia and dysplasia in Barrett's esophagus

The histologic diagnosis of Barrett's dysplasia requires the identification of intestinal metaplasia, which often presents a challenge due to sampling error, observer variation, and difficulty in histologic interpretation. Particularly problematic is the separation of negative, indefinite, and low-grade dysplasia, the varied histological appearances of high-grade dysplasia, and the diagnosis of suboptimal biopsy material. This article seeks to aid in the histological evaluation of metaplasia and dysplasia in Barrett's esophagus.

Clinical characteristics, biologic behavior, and survival after esophagectomy are similar for adenocarcinoma of the gastroesophageal junction and the distal esophagus

OBJECTIVE

The Siewert classification system differentiates between adenocarcinoma of the gastroesophageal junction and that of the distal esophagus. The purpose of this study was to evaluate whether there were differences in the location and prevalence of lymph node metastases, type of recurrence, and survival with these tumors that warrant distinguishing between them in clinical practice.

METHODS

Records of all patients who underwent resection for adenocarcinoma of the distal esophagus or gastroesophageal junction from 1987 to 2007 were retrospectively reviewed. Based on the endoscopic location of the epicenter of the tumor in relation to the gastroesophageal junction, tumors were categorized in 301 patients as being of the distal esophagus and in 208 as being of the gastroesophageal junction.

RESULTS

There were no significant differences in age, sex, or body mass index between patients with adenocarcinoma of the distal esophagus or gastroesophageal junction. Patients with adenocarcinoma of the distal esophagus were more likely to have reflux symptoms (75% vs 53%, P < .0001) and peritumoral intestinal metaplasia (73% vs 51%, P < .0001) and be in a surveillance program (54% vs 9%, P = .0005) compared with patients with adenocarcinoma of the gastroesophageal junction. However, the prevalence and location of nodal metastases was similar, and in node-positive patients mediastinal node involvement was present in more than 40% of the patients in each group (distal esophageal adenocarcinoma, 47%; gastroesophageal junction adenocarcinoma, 41%). Survival was similar (5 years: distal esophageal adenocarcinoma, 45%; gastroesophageal junction adenocarcinoma, 38%; P = .14), as was the prevalence and type of recurrence.

CONCLUSION

The prevalence and distribution of lymph node metastases in patients with adenocarcinoma of the distal esophagus and gastroesophageal junction were similar, and after esophagectomy, there was no difference in overall survival or recurrence. Efforts to differentiate between these tumors are unnecessary, and both are effectively treated with esophagectomy.

Pediatric columnar lined esophagus vs Barrett's esophagus: is it the time for a consensus definition

We describe the clinical, endoscopic, and histological features of all cases of Barrett's esophagus (BE) diagnosed at our institution between 2000 and 2007 following the criteria of the British Society of Gastroenterology. This society defines BE as a segment of columnar metaplasia (CLO) (whether intestinalized or not) of any length, visible endoscopically above the gastroesophageal junction and confirmed histologically. The diagnosis was challenged after immunostaining for Cdx2 (marker of intestinal differentiation). Information was collected with respect to age, symptoms, treatment, and endoscopic and histological features. Twelve children (10 males and 2 females) with a median age of 11.7 (2 to 17) years had been diagnosed with CLO-BE. Histology confirmed BE in 31 of 38 endoscopies. The initial diagnosis was reviewed according to Cdx2 results in 10 of 12 patients: Cdx2 strongly expressed in 4 cases with intestinal metaplasia (the diagnosis of BE was maintained); was negative in 4 other patients with "CLO" mucosa (reviewed diagnosis was that of expansion of the gastric cardia into the distal esophagus); and 2 patients had occasional Cdx2-positive cells showing cardia-type mucosa with goblet cells (early BE?). The estimated prevalence of CLO-BE in the pediatric population of South Yorkshire (United Kingdom) is 0.0024%, 0.8% in children referred for endoscopy and 5.5% in the children with reflux esophagitis. Characterization of the BE and confirmation of intestinal differentiation may have prognostic implications that can impact the surveillance program. Our results showed that intestinal differentiation as demonstrated with Cdx2 was only seen if goblet cells were present. A consensus definition and further studies to understand the molecular mechanisms involved in the development of BE at this age are needed.

The definition and management of Barrett's oesophagus: a case report, review of the literature and a suggestion for the future

The definition of Barrett's oesophagus continues to evolve and there has been divergence in the diagnostic criteria internationally, which has implications for surveillance practices and research inclusion criteria. Here we describe the case of a 69-year-old female with 10 cm of gastric-type columnar-lined oesophagus confirmed on histochemical staining. Surveillance biopsies, performed according to protocol, revealed an intramucosal adenocarcinoma. The patient was successfully treated with a transhiatal oesophagectomy and a detailed examination of the entire surgical specimen confirmed that the columnar oesophagus was lined by gastric villiform mucosa complicated by intramucosal carcinoma, on the background of dysplasia with no intestinal metaplasia. This highlights the spectrum of metaplastic epithelia that can harbour malignant potential. There is a need for an international consensus on the classification of Barrett's oesophagus to aid research progress. Therefore, we propose a new classification for Barrett's oesophagus based on a combination of endoscopic and histopathological features.

Histological assessment of oesophageal columnar mucosa

This review presents the pathological features of Barrett's oesophagus, with an emphasis on the role of pathologists in the diagnosis, surveillance and treatment of the disease. The diagnosis of Barrett's oesophagus is based both on endoscopy and histology. The surveillance of patients relies on systematic biopsy sampling, looking for dysplasia - intraepithelial neoplasia. Well established classifications of dysplasia are now used by pathologists, but there remain problems with this marker. Therefore, many alternative biomarkers have been proposed, that remain of limited interest in daily practice, including DNA-ploidy, proliferation markers, and p53 abnormalities. Endoscopic improvements already allow a better selection of biopsies, and it may be that new technologies will allow 'virtual biopsies'. The role of pathologists is now extended to the evaluation of new therapeutic modalities of early neoplastic lesions in Barrett's oesophagus, especially endoscopic mucosal resection.

The normal anatomy around the oesophagogastric junction: an endoscopic view

Where the oesophagus ends and the stomach begins has been a bone of contention for decades between the histologist, physiologist, gastroenterologist, radiologist and surgeon. The oesophagogastric junction (OGJ) is an important anatomical region because of its essential functions in relation to swallowing and as a site of structural defects, inflammation, metaplasia and neoplasia. The location of the diaphragmatic hiatus in relation to the distal oesophagus, the level of the squamocolumnar mucosal junction (SCJ), the location of the distal margin of the mucosal palisade veins and the proximal margin of the gastric mucosal folds are features that permit an accurate endoscopic diagnosis of hiatal hernia and reflux sequelae, including even a minimal extent for Barrett's oesophagus. The physiological OGJ region can be considered to be between the rosette of the lower oesophageal sphincter (LOS) and the angle of His. The most reliable benchmarks for the precise mural OGJ that can be identified during endoscopy are the levels of the cephalad margins of the linear gastric mucosal folds, viewed with the lumen deflated as much as possible, that are juxtaposed to the level of the caudad extent of the oesophageal mucosal palisade veins.

Control of gastric acid secretion in health and disease

Recent milestones in the understanding of gastric acid secretion and treatment of acid-peptic disorders include the (1) discovery of histamine H(2)-receptors and development of histamine H(2)-receptor antagonists, (2) identification of H(+)K(+)-ATPase as the parietal cell proton pump and development of proton pump inhibitors, and (3) identification of Helicobacter pylori as the major cause of duodenal ulcer and development of effective eradication regimens. This review emphasizes the importance and relevance of gastric acid secretion and its regulation in health and disease. We review the physiology and pathophysiology of acid secretion as well as evidence regarding its inhibition in the management of acid-related clinical conditions.