On the existence and location of cardiac mucosa: an autopsy study in embryos, fetuses, and infants

Gastro-Esophageal Junction Precancerosis: Histological Diagnostic Approach and Pathogenetic Insights

Barrett's esophagus (BE) was initially defined in the 1950s as the visualization of gastric-like mucosa in the esophagus. Over time, the definition has evolved to include the identification of goblet cells, which confirm the presence of intestinal metaplasia within the esophagus. Chronic gastro-esophageal reflux disease (GERD) is a significant risk factor for adenocarcinoma of the esophagus, as intestinal metaplasia can develop due to GERD. The development of adenocarcinomas related to BE progresses in sequence from inflammation to metaplasia, dysplasia, and ultimately carcinoma. In the presence of GERD, the squamous epithelium changes to columnar epithelium, which initially lacks goblet cells, but later develops goblet cell metaplasia and eventually dysplasia. The accumulation of multiple genetic and epigenetic alterations leads to the development and progression of dysplasia. The diagnosis of BE requires the identification of intestinal metaplasia on histologic examination, which has thus become an essential tool both in the diagnosis and in the assessment of dysplasia's presence and degree. The histologic diagnosis of BE dysplasia can be challenging due to sampling error, pathologists' experience, interobserver variation, and difficulty in histologic interpretation: all these problems complicate patient management. The development and progression of Barrett's esophagus (BE) depend on various molecular events that involve changes in cell-cycle regulatory genes, apoptosis, cell signaling, and adhesion pathways. In advanced stages, there are widespread genomic abnormalities with losses and gains in chromosome function, and DNA instability. This review aims to provide an updated and comprehensible diagnostic approach to BE based on the most recent guidelines available in the literature, and an overview of the pathogenetic and molecular mechanisms of its development.

Cardiac mucosa in neonates

BACKGROUND

The histology of the cardiac mucosa at the esophagogastric junction (EGJ) at birth is still a controversy. We conducted a histopathological study of the EGJ to clarify the morphology, and to determine the presence or absence of cardiac mucosa at birth.

SUBJECTS

We examined 43 Japanese neonates and infants that are born prematurely or at full term. Death had occurred between 1 and 231 days after birth.

RESULTS

Cardiac mucosa without parietal cells showing positivity for anti-proton pump antibody, adjacent to the most distal squamous epithelium, was observed in 32 (74%) of the 43cases. Such mucosa was evident in neonates that were full-term and had died within 14 days after birth. On the other hand, cardiac mucosa with parietal cells adjacent to squamous epithelium was noted in 10 cases (23%); the remaining one (2%) had columnar-lined esophagus. Squamous and columnar islands were observed in a single histological section from the EGJ in 22 (51%) of the 43 cases. Parietal cells were sparsely or densely present in the gastric antral mucosa.

CONCLUSIONS

On the basis of these histological findings, we consider that cardiac mucosa exists in neonates and infants and can be defined as such, irrespective of the presence or absence of parietal cells (so-called oxyntocardiac mucosa). Neonates born prematurely or at full-term have cardiac mucosa in the EGJ just after birth, as is the case for Caucasian neonates.

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.

Unraveling the identity of gastric cardiac cancer

The classification of gastric cardiac carcinoma (GCC) is controversial. It is currently grouped with esophageal adenocarcinoma (EAC) as an adenocarcinoma of the gastroesophageal junction (GEJ). Recently, diagnostic criteria for adenocarcinoma in the GEJ were established and GCC was separated from EAC. We viewed published evidence to clarify the GCC entity for better patient management. GCC arises in the cardiac mucosa located from 3 cm below and 2 cm above the GEJ line. Compared with EAC, GCC is more like gastric cancer and affects a higher proportion of female patients, younger patients, those with a lower propensity for reflux disease, a wider histopathologic spectrum, and more complex genomic profiles. Although GCC pathogenesis mechanisms remain unknown, the two-etiology proposal is appealing: in high-risk regions, the Correa pathway with Helicobacter pylori infection, chronic inflammation, low acid and intestinal metaplasia, dysplasia and carcinoma may apply, while in low-risk regions the sequence from reflux toxin-induced mucosal injury and high acid, to intestinal metaplasia, dysplasia and carcinoma may occur. In early GCC a minimal risk of nodal metastasis argues for a role of endoscopic therapy, whereas in advanced GCC, gastric cancer staging rules and treatment strategy appear to be more appropriate than the esophageal cancer staging scheme and therapy for better prognosis stratification and treatment. In this brief review we share recent insights into the epidemiology, histopathology and genetics of GCC and hope that this will stimulate further investigations in order to improve the clinical management of patients with GCC.

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.

Endoscopic findings of esophagogastric junction in children

Esophagogastric landmarks are recognizable in the same way both in children and in adults, and palisade-shaped vessels can be observed at the distal position of esophageal mucosa, even in infants. Few studies have been done in respect to Barrett's esophagus (BE) in children. Incidence of endoscopically suspected BE among all children undergoing esophagogastroduodenoscopy (EGD) is approximately 0.25-1.4%, but can be up to 9.7% in patients with gastroesophageal reflux disease (GERD). Some data suggest that BE is an acquired disorder and point to the possibility of a congenital component in combination with severe mucosal injury. Recent reports noted that multilayered epithelium (ME), which shows morphological and immunocytochemical characteristics of both squamous and columnar epithelium, is associated with goblet cell metaplasia in adult patients with columnar-lined esophagus. The role of ME in the development of intestinal metaplasia in children is uncertain. Furthermore, detailed mechanisms about how short-segment BE (SSBE) changes to long-segment BE (LSBE) are not yet well understood. Further studies are required to understand the pathological esophagogastric junction (EGJ) and BE in children based on reliable epidemiological data and analysis especially in children who have reflux symptoms. Better understanding of the pediatric EGJ and BE may allow improved diagnosis, monitoring, therapy and, therefore, prognosis of GERD-related disorders in adulthood.

Considering the esophagogastric junction as a 'zone'

Siewert's classification of adenocarcinoma of the esophagogastric junction (EGJ) classifies tumors anatomically for determining the appropriate surgical technique. According to this classification, a type II tumor, true carcinoma of the cardia, is defined as a cancer within 1 cm proximal to 2 cm distal of the EGJ. Histological analysis indicates that the cardiac gland is present with a high degree of frequency between 1-2 cm to the gastric side and 1-2 cm to the esophageal side of the EGJ, which means that this zone can be considered as neither the stomach nor the esophagus but rather as a third zone known as the 'EGJ zone'. It has been suggested that there are multiple causes for development of adenocarcinoma in the EGJ zone. The TNM Classification of Malignant Tumours 7th Edition considers EGJ adenocarcinoma (EGJAC) occurring in the EGJ zone to be a part of esophageal adenocarcinoma (EAC). However, recent studies have indicated that EGJAC behaves differently from EAC and gastric carcinoma. Barrett's esophagus is now considered an important factor in the etiology of EGJAC, but, as yet, no studies have elucidated the differences between cancer arising from short-segment Barrett's esophagus and cancer of the gastric cardia. Thus, there is currently no clinical relevance to subdivision of adenocarcinoma in the EGJ zone into above or below the EGJ line.

Recent advances in proximal gastric carcinoma

The American Joint Committee on Cancer (AJCC) staging scheme requires staging proximal gastric carcinoma (PGC) as esophageal adenocarcinoma (EAC), which has been shown to be controversial by recent research results. To update the current research findings on PGC, we systematically reviewed and analyzed the scientific evidence on key arguments related to PGC. The data of high-quality research articles showed that PGC arised in the cardiac mucosa in the proximal stomach within 3 cm below the gastroesophageal junction. Its incidence is rising in East Asian countries, but decreasing in the West, and plateaued at a low level in the United States. PGC is a slowly progressive cancer with unknown independent risk factors and the mechanisms of pathogenesis. This carcinoma exhibits a wide histopathological spectrum and heterogeneous post-resection patient survival characteristics, and cannot be adequately staged for prognotic stratification by the current AJCC staging classification. The results on PGC genomics reveal unique genetic profiles, especially in East Asian populations. In conclusion, mounting evidence defies a simple placement of PGC in a single category of EAC for disease classification; further investigations on the mechanisms of PGC pathogenesis are urgently needed.

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.

Cardiac mucosa at the gastroesophageal junction: An Eastern perspective

AIM: To investigate the nature and origin of cardiac mucosa (CM).

METHODS: Biopsy samples from sixty-one individuals were included in this study. The specimens were taken “at”, “just below”, or “just above” the gastroesophageal junction, including the histologic squamocolumnar junction. Clinical data were obtained by reviewing electronic medical records for each patient. Patients with a history of stomach adenoma or carcinoma and esophageal carcinoma were excluded, and cases that were endoscopically suspicious of Barrett’s esophagus or a polyp were also ruled out. Histologic and endoscopic reviews were performed blinded to the patient’s clinical data. Histologic evaluation was conducted by two pathologists, and endoscopic review was performed by a endoscopist with wide experience in the field. Histologically, the columnar epithelium of squamocolumnar junction, presence and severity of acute and chronic inflammation, atrophy, intestinal metaplasia, and presence of carditis were evaluated. Endoscopically, reflux esophagitis was evaluated by Los Angeles (LA) classification, hiatal hernias were classified by Hill grade, and gastroesophageal flap valves were assessed.

RESULTS: Fifty-nine of the 61 (96.7%) patients were Korean; 65.6% (40/61) of the patients underwent endoscopy according to the schedule of the National Health Insurance Program as a screening inspection. Of these, only 20.0% (8/40) of cases had reflux symptoms. CM was present in 41/61 (67.2%) individuals, and its presence was associated with older age compared to oxyntocardiac mucosa/oxyntic mucosa (60.59 ± 2.02 years vs 51.55 ± 3.35 years; P = 0.018). The presence of CM was associated with endoscopic diagnosis of esophagitis according to the LA classification (P = 0.022). CM was associated with mononuclear cell infiltration and neutrophilic infiltration, which were statistically significant (P = 0.001, and P = 0.004, respectively). The inflammation of CM, “carditis”, showed a statistically significant association with endoscopic diagnosis of reflux esophagitis according to the LA classification (P = 0.008).

CONCLUSION: CM at the gastroesophageal junction is a common histologic finding in biopsy specimens, though not always present, and associated with gastroesophageal reflux disease and carditis severity.

Obesity and related risk factors in gastric cardia adenocarcinoma

Over recent decades, the incidence of cancers of the gastroesophageal junction, including gastric cardia tumors, has increased markedly. This is a trend that has been well documented, especially in studies from the USA and northern Europe that have also demonstrated a concomitant rise in the ratio of cardia to distal gastric cancers. The rise in the prevalence of gastric cardia adenocarcinoma has been paralleled by the worldwide obesity epidemic, with almost all epidemiological studies reporting increased body mass index and obesity increase the risk of cardia cancer development. However, the strength of this association is less marked than the link between obesity and esophageal adenocarcinoma, and the mechanisms remain poorly understood. Other possible confounders of the relationship between obesity and cardia cancer include the decline in Helicobacter pylori infection and the widespread use of proton pump inhibitors, although these have rarely been controlled for in case-control and cohort studies investigating associations between obesity and cardia cancer. We review these epidemiological trends and discuss proposed mechanisms for the association, drawing attention to controversies over the difficulty of defining cardia cancer. The relative paucity of high-quality epidemiological studies from other regions of the world should prompt further investigation of this issue, especially in populations undergoing rapid socioeconomic change.

Cardiac mucosa at the gastro-oesophageal junction: indicator of gastro-oesophageal reflux disease? Data from a prospective central European multicentre study on histological and endoscopic diagnosis of oesophagitis (histoGERD trial)

AIMS

The origin and significance of cardiac mucosa at the gastro-oesophageal junction are controversial. In the prospective Central European multicentre histoGERD trial, we aimed to assess the prevalence of cardiac mucosa, characterized by the presence of glands composed of mucous cells without parietal cells, and to relate its presence to features related to gastro-oesophageal reflux disease (GORD).

METHODS AND RESULTS

One thousand and seventy-one individuals (576 females and 495 males; median age 53 years) were available for analysis. Overall, in biopsy specimens systematically taken from above and below the gastro-oesophageal junction, cardiac mucosa was observed in 713 (66.6%) individuals. Its presence was associated with patients' symptoms and/or complaints (P = 0.0025), histological changes of the squamous epithelium (P < 0.001) indicative of GORD, intestinal metaplasia (P < 0.001), and an endoscopic diagnosis of oesophagitis (P < 0.001). No association with an endoscopic diagnosis of Barrett's oesophagus or with gastric pathology, particularly Helicobacter infection, was observed.

CONCLUSIONS

Cardiac mucosa is a common finding in biopsy specimens taken from the gastro-oesophageal junction. Its association with reflux symptoms, histological changes indicating GORD and the endoscopic diagnosis of oesophagitis suggests that injury and repair related to GORD contribute to its development and/or expansion.

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.

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.

Magnetic resonance imaging of the normal fetal esophagus

OBJECTIVES

To establish the appearance on magnetic resonance imaging (MRI) of the normal fetal esophagus and to provide biometric data from 20 to 39 gestational weeks.

METHODS

In this retrospective study of 250 fetal MRI examinations (20-39 gestational weeks) the visibility of the upper (E1, cervical to tracheal bifurcation) and lower (E2, tracheal bifurcation to diaphragm) esophageal segments was assessed separately in each of three section planes. Segments were scored as being visible or not, and whether they were fluid-filled was noted. Maximum esophageal diameters were recorded. To study the age dependency of esophageal visualization, fetuses were divided into three age groups: 20-25, 26-31 and 32-39 weeks. In 19 cases, there were dynamic studies and these were analyzed for the duration of fluid-filling.

RESULTS

Segment E1 was visualized only when it was fluid-filled and it was visible in 16.8% of axial, 4% of frontal and 22.4% of sagittal acquisitions. Segment E2 could also be detected in the unfilled state, when it appeared solid; it was seen in 96.4% of axial, 74% of frontal and 39.6% of sagittal acquisitions, being fluid-filled in 62.7-88.9% of these. Depending on the amount of fluid-filling and the gestational age, E2 segments had a variable appearance. Dynamic scans showed E1 segments to be fluid-filled for periods of 0.5-1.5 s and E2 segments for periods of 3-35 s. Both the frequency of visualization and the maximum diameter increased linearly with gestational age.

CONCLUSION

Visualization of the fetal esophagus by MRI depends on section plane, segment and gestational age, with considerable differences between the two segments: while E1 requires fluid-filling related to fetal swallowing, the E2 portion can usually be demonstrated independent of fluid-filling, as a consequence of its topographical relationships. The frequently fluid-filled state of E2 may reflect the immature nature of esophageal neuromuscular activity, and the lack of an anti-reflux mechanism due to the short length of the abdominal esophagus.

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 columnar-lined mucosa in the distal esophagus. A preliminary study in baboons

BACKGROUND

For anatomists, the cardia is a portion of the stomach. However, at the histological level, the cardiac mucosa, described as columnar-lined with mucus-producing glands (CLMMG), is for some pathologists part of the stomach (already present at birth) and for others a metaplastic change of the esophagus induced by gastroesophageal reflux (GER).

MATERIALS AND METHODS

The distal esophagus and the proximal stomach of 5 adult male baboons were removed en bloc at autopsy. The distance between the most distal part of the squamous epithelium of the esophagus and the first oxyntic fundic gastric gland (representing the entire CLMMG) was assessed using an ocular microscale.

RESULTS

The length of the CLMMG varied from 1.2 mm to 12.4 mm. The CLMMG had replaced the squamous epithelium of the distal esophagus in all 5 baboons.

DISCUSSION

Regurgitation with rumination is a natural physiological, daily, recurrent process in baboons that leads to GER. The luminal cytoplasmic vacuoles with neutral mucins contained in the columnar cells and the neutral mucins produced by the mucin glands buffer the low pH of the gastric juices that reflux into the distal esophagus. This protective action against the acid refluxate cannot be achieved by the squamous epithelium.

CONCLUSION

The results of this preliminary investigation suggest that in baboons, CLMMG is an adaptation process of the esophageal mucosal to the low pH microenvironment conveyed by protracted GER.

Prevalence and histological features of the gastric cardia-type mucosa in children

BACKGROUND

It has been suggested that the presence of gastric cardia in adults (with or without inflammation or intestinal cells) is a metaplastic condition. The presence of gastric cardia in children would argue against this contention. We examined the presence and determinants of gastric cardia-type mucosa at a normally located z-line in children without underlying gastroesophageal reflux disease (GERD)-predisposing disorders.

METHODS

We conducted a prospective study of consecutive pediatric patients undergoing routine upper endoscopy. We excluded patients with coagulopathy or bleeding disorder, prior gastric or esophageal surgery, major congenital disorders, or neurodevelopmental disorders. Biopsies were obtained with the endoscope in the anterograde position within 5 mm below the endoscopic z-line, and were examined for the presence of gastric cardia-type mucosa, defined as both mucous and oxynto-mucous glands.

RESULTS

Eighteen (47%) of 38 subjects has gastric cardia mucosa. There were no significant differences in age, gender, or race between patients with and without gastric cardia-type mucosa. There were no differences between the groups in weight and height either at birth or at the time of endoscopy, in the mother's age at childbirth or history of peripartum problems. There were no differences in symptoms suggestive of reflux such as spitting up or difficulty of gaining weight. Neither history of gastroesophageal testing nor histological esophagitis (38% versus 40%) was different between the groups with and without gastric cardia-type mucosa.

CONCLUSIONS

Gastric cardia-type mucosa is unlikely to be a metaplastic condition since it is present in a large proportion of children undergoing endoscopy. Neither histological esophagitis nor GERD symptoms are significantly associated with the presence of gastric cardia-type mucosa.

The columnar-lined mucosa at the gastroesophageal junction in non-human primates

Despite that anatomists consider the cardia as a portion of the stomach, there is disagreement in the literature over whether the cardia mucosa, described as columnar-lined with mucus-producing glands (CLMMG) with or without occasional interspersed oxyntic cells, is part of the stomach, part of the esophagus or a distinct entity. For some authors this mucosa phenotype is a metaplastic glandular change of the distal esophagus caused by protracted gastro-esophageal reflux (GER). In this survey, the presence of CLMMG mucosa was searched for at the esophagus-gastric junction in 50 non-human primates (NHP). The length of the CLMMG (between the squamous epithelium of the esophagus and the first oxyntic fundic gastric gland) was assessed by the aid of an ocular microscale. In all three foetuses, all four stillborn baboons and one 4 day old baboon, the columnar-lined mucosa showed depressions that corresponded to early epithelial pits without glands. In the remaining 45 post-natal NHP, the length of the CLMMG mucosa varied from 0.8 mm to 25.2 mm, and the CLMMG mucosa had replaced the distal esophageal squamous epithelium. The size was neither influenced by the post-natal age nor by the gender of the animals. In NHP, regurgitation with rumination is a natural physiological process leading to GER. The present investigation substantiates the notion that the columnar-lined mucosa with mucus-producing glands is a post-natal developmental process in NHP. These animals seem to offer an excellent spontaneous model to study the series of histological events that take place in the distal esophagus of NHP, most likely under the influence of protracted GER.

Adenocarcinomas of the distal esophagus and "gastric cardia" are predominantly esophageal carcinomas

BACKGROUND

Adenocarcinoma of the distal esophagus and gastric cardia are defined by the relationship of its epicenter to the gastro-esophageal junction, which is presently defined as the end of the tubular esophagus. We have recently suggested that the true gastro-esophageal junction is best defined by the proximal limit of gastric oxyntic mucosa.

AIM

To reclassify adenocarcinomas of this region by the relationship of the tumor to the proximal limit of gastric oxyntic mucosa.

METHODS

Seventy-four patients who had esophago-gastrectomy for adenocarcinomas in this region were classified as adenocarcinoma of distal esophagus (38 patients) and gastric cardia (36 patients) by present criteria. The epithelial type at the epicenter and distal edge of these tumors was assessed.

RESULTS

The epicenter of the tumor in 64 patients with noncircumferential tumors had squamous (5 cases), cardiac (21 cases), oxynto-cardiac (4 cases), and intestinal (Barrett-type) (34 cases) epithelia. None had gastric oxyntic mucosa. Of the 10 patients with circumferential tumors, 7 had cardiac or oxynto-cardiac epithelium at the distal tumor edge.

CONCLUSIONS

If the gastro-esophageal junction is defined histologically as the proximal limit of oxyntic mucosa, 71/74 patients would be classified as adenocarcinoma of the distal esophagus. The other 3 patients were questionable as to gastric or esophageal origin. We suggest that this reclassification based on the proposed new definition of the gastro-esophageal junction provides an explanation for the epidemiologic relationship that exists between adenocarcinoma of the "gastric cardia" and gastro-esophageal reflux disease.

Barrett's esophagus and adenocarcinoma of the gastroesophageal junction: a pathologic perspective

Barrett's esophagus is defined clinically by the presence of endoscopically evident columnar mucosa in the distal esophagus with histopathologic confirmation of the presence of intestinal-type epithelium. The etiology of Barrett's esophagus is understood poorly, but chronic gastroesophageal reflux disease is considered a major contributing factor. Barrett's esophagus is associated with the development of adenocarcinoma of the gastroesophageal junction. It is believed that the development of a Barrett-type mucosa with intestinal goblet-type cells is due to an altered process of differentiation of pluripotent epithelial stem cells in response to the local injury and repair process. The potential identification and isolation of markers for screening purposes and possibly prognostic information are areas of considerable clinical and scientific interest.

Cancer of the gastric cardia

Current evidence indicates that cardia cancers are of at least two distinct and disparate aetiologies. One type resembles cancer of the more distal stomach (Type A), being a consequence of atrophic gastritis due to Helicobacter pylori infection or more rarely autoimmune atrophic gastritis. Another type (Type B) resembles oesophageal adenocarcinoma and is likely to be a consequence of short-segment gastro-oesophageal reflux disease. The two cancers are themselves indistinguishable but examination of the gastric phenotype indicates the aetiology: Type A occurring in patients with evidence of atrophic gastritis whereas Type B occurs in subjects with healthy acid secreting stomachs. In subjects with healthy acid secreting stomachs the cardia has a specific luminal chemistry remaining highly acidic and unbuffered following a meal and having very active nitrosative chemistry due to the acidification of nitrite in saliva. This luminal chemistry may contribute to the high incidence of metaplasia and neoplasia at this anatomical site.

Prospective analysis of patients with adenocarcinoma of the gastric cardia and lymph node metastasis in the proximal field of the chest

BACKGROUND

The extent to which adenocarcinoma of the cardia with lymph node metastasis in the upper mediastinum is amenable to cure by radical surgery is open to debate. It remains unclear whether these relatively distant metastases have an effect on long-term survival. The aim of this study was to identify the incidence of such positive nodes and evaluate their prognostic significance.

METHODS

Some 50 patients with adenocarcinoma of the gastric cardia and substantial invasion of the oesophagus (junctional type II), who underwent an extended transthoracic oesophagectomy as part of a prospective randomized trial between 1994 and 2000, were studied.

RESULTS

Eleven patients (22 per cent) had lymph node metastasis in the proximal field of the chest. These patients had more positive nodes overall (P = 0.020) and a shorter median survival (P = 0.009) than those without such metastasis. Multivariate analysis identified positive nodes in the proximal field as an independent predictor of poor survival.

CONCLUSION

Lymph node metastasis in the proximal field of the chest is common and is an indicator of poor prognosis in patients with adenocarcinoma of the cardia.

On the origin of cardiac mucosa: A histological and immunohistoc-hemical study of cytokeratin expression patterns in the developing esophagogastric junction region and stomach

AIM To examine the fetal and neonatal esophagogastric junction region (EGJ) histologically for the presence of an equivalent to adult cardiac mucosa (CM); to study the expression patterns of all cytokeratins (CK) relevant to the EGJ during gestation; to compare the CK profile of the gestational and the adult EGJ; and to determine the degree of development in the adult EGJ histology and CK profile during gestation.

METHODS: Forty-eight fetal autopsy specimens of the EGJ were step-sectioned and stained with hematoxylin and eosin (H&E) to select sections showing the mucosal lining. Immunohistochemistry for CK5, 7, 8, 13, 18, 19, and 20 was performed. Antibody staining was then graded for location, intensity, and degree.

RESULTS: The distal esophagus was lined by simple columnar epithelium from 12-wk gestational age (GA). The proximal part of this segment consisted of mucus-producing epithelium, devoid of parietal cells. CK5 and 13 were present exclusively in multilayered epithelia and CK8, 18, and 19 predominantly in simple columnar epithelium. There were no differences in the frequencies of the co-ordinate CK7+/20+ and the CK7-/20- immunophenotypes between different locations. The prevalence of the CK7+/20- immunophenotype decreased, and that of the CK7-/20+ immunophenotype increased significantly from the distal esophagus to the distal stomach.

CONCLUSION: Fetal columnar-lined lower esophagus (fetal CLE) may be the equivalent and precursor of the short segments of columnar epithelium found in the distal esophagus of some normal adult subjects. Esophageal simple columnar epithelium without parietal cells (ESN) may be the precursor of adult CM. The similarities between the fetal and adult EGJ and stomach CK expression patterns support the conclusion that adult CM has an identifiable precursor in the fetus. This would then indicate that at least a part of the adult CM has a congenital origin.

Is Adenocarcinoma of the Esophagogastric Junction or Cardia Different From Barrett Adenocarcinoma?

Over time the relative distribution of cancers of the proximal digestive tract has changed. Squamous cell carcinomas of the esophagus have become less common, while numbers of adenocarcinomas have greatly increased. This shift most likely reflects an increase in the incidence of gastroesophageal reflux. Moreover, there is a decline in the incidence of distal gastric cancer, which in turn may be related to Heliobacter pylori eradication. Simultaneously, there is a time trend toward a more proximal localization of gastric cancer. If the above-mentioned etiopathologic links are correct, this could indicate that the so-called cardia adenocarcinomas are not related to H pylori infection and that they may instead be related to gastroesophageal reflux and eventually may not be considered to be “gastric” cancers. The rapidly growing quantity of literature on this subject is, however, confounding. A major source of discordance would seem to be a Babylonian confusion of tongues concerning the terms cardia and cardiac carcinomas. Unfortunately, this confusion is also apparent in the classification systems available for staging of cancer, thus closing the “vicious” circle.

Detection of cardia intestinal metaplasia: do the biopsy number and location matter?

BACKGROUND AND AIM

Presence of intestinal metaplasia in the gastric cardia (cardia intestinal metaplasia, CIM) has been reported in 5-34% of patients undergoing upper endoscopy and is a topic of interest given the rising incidence of cancer in this location. The aim of this article is to determine the prevalence of CIM in biopsies obtained from two separate locations within the gastric cardia.

METHODS

Patients presenting to the endoscopy unit for upper endoscopy for any symptoms were invited to participate in the study. The biopsy protocol included: eight biopsies from the gastric cardia, four from upper cardia (forceps across the squamocolumnar junction), four from lower cardia (within 1 cm of upper cardia), and four each from the gastric body and antrum. All cardia biopsies were stained with hematoxylin and eosin (H&E) and alcian blue at pH 2.5 for the presence of goblet cells and the body/antrum biopsies were stained with Steiner silver stain for Helicobacter pylori detection. In patients testing negative for H. pylori by histology, a serology test was performed.

RESULTS

Sixty-five patients have been evaluated by this protocol; median age 54 yr (range: 34-81 yr), 63 males, 53 Caucasians, and 12 African Americans. The detection of CIM was as follows: upper cardia only, 7, both upper and lower cardia, 5, and lower cardia only, 7. Thus, CIM was detected in 12 patients (18%) in the upper cardia biopsies, in 12 patients (18%) in the lower cardia; overall prevalence of CIM was 29% (19 patients). Fifty-eight percent of CIM patients tested positive for H. pylori by either histology or serology. The addition of serology allowed for the detection of eight additional H. pylori-positive CIM patients.

CONCLUSIONS

The prevalence of CIM in this study was similar (18%, four biopsies) at each location; however, if both locations were considered (eight biopsies), the prevalence increased to 29%. Thus, CIM prevalence may vary depending on the number of biopsies obtained as well as on the location of biopsies. Use of additional testing detects more patients who are H. pylori positive and should be performed if association of CIM with H. pylori is contemplated. Future endoscopic studies of the gastric cardia should specify the location of biopsies, the number of biopsies obtained, and the tests used to diagnose H. pylori.

Review article: prevalence of Barrett's oesophagus and metaplasia at the gastro-oesophageal junction

Barrett's oesophagus, a complication of chronic gastro-oesophageal reflux disease, is the premalignant lesion for oesophageal and gastro-oesophageal junction adenocarcinoma. Described in the 1950s by Norman Barrett, the diagnostic criterion for this lesion has evolved significantly over the last three decades. Endoscopic Barrett's oesophagus requires the recognition of columnar mucosa in the distal oesophagus; documentation of metaplastic tissue is confirmed by random biopsies. Given this changing definition of Barrett's metaplasia, the prevalence rates vary in the literature depending on the diagnostic criteria applied. However, it is generally accepted that approximately 10% of patients with chronic gastro-oesophageal reflux disease will be diagnosed with this condition. There are no population-based studies on the prevalence of Barrett's oesophagus, but emerging data indicate that it may be equally prevalent in asymptomatic individuals. These studies require confirmation. Although the incidence of oesophageal adenocarcinoma is increasing rapidly, it is unclear whether the true incidence of Barrett's oesophagus is increasing at the same time. On the other hand, metaplasia at the gastro-oesophageal junction appears to be distinct from Barrett's oesophagus, is probably not related to chronic gastro-oesophageal reflux disease and is a common finding if routine biopsies are obtained at the gastro-oesophageal junction. This article reviews our current understanding of the diagnosis, definition and prevalence of both of these lesions.

Carditis in patients with gastro-oesophageal reflux disease: results of a controlled study based on both endoscopy and 24-h oesophageal pH monitoring

BACKGROUND

There are conflicting reports on the role of gastro-oesophageal reflux disease (GERD) and Helicobacter pylori infection in the aetiology of carditis.

AIM

The role of reflux and H. pylori infection in causing carditis was assessed in 113 consecutive patients with GERD and in 25 controls.

METHODS

All subjects underwent endoscopy and pH test and carditis was diagnosed on biopsies taken across the squamocolumnar junction. Helicobacter pylori was assessed by histology and rapid urease test. GERD was diagnosed by endoscopic oesophagitis or abnormal pH test.

RESULTS

Carditis was detected in 53 of 71 GERD patients and in 15 of 20 controls. Among patients, 18 showed absent, 39 mild and 14 marked cardia inflammation and their H. pylori infection rates were 17, 23 and 57%, respectively (P < 0.025). Most patients with carditis (68%) lacked H. pylori infection. pH-metry was abnormal in 15 of 18 patients with normal cardia, 33 of 39 with mild carditis and 12 of 14 with marked inflammation.

CONCLUSIONS

Carditis is a frequent finding in GERD and controls. Mild, non-active carditis is frequent in GERD patients. Marked inflammation is associated with both H. pylori and abnormal pH testing. Thus, both GERD and H. pylori infection may play a role in inducing carditis.

Carditis at the interface between GERD and Helicobacter pylori infection

Inflammation of the gastric cardia ('carditis') is a histological diagnosis. It seems reasonable to transfer histological criteria of the updated Sydney classification from the distal stomach to the cardia as long as a special classification of inflammation of the esophagogastric junction is lacking. The two best characterized causes of carditis are Helicobacter pylori infection and gastroesophageal reflux disease (GERD). However, the causal contribution and interference of these two factors are highly controversial, as is the clinical relevance of carditis in terms of eliciting symptoms or conferring an increased cancer risk. Variability of studies on carditis is based on conflicting concepts of the normal anatomy of the esophagogastric junction. Cardia-type mucosa (CM) apparently exists at birth as a tiny circular area, and extends to a larger area in adulthood. This implies that cardia-type mucosa is largely metaplastic. Metaplastic CM may evolve in the lower esophagus as a consequence of GERD. It is a general phenomenon that H. pylori-induced gastritis also involves the gastric cardia, irrespective whether the cardia is lined by fundus-type mucosa or CM. The contribution of GERD to inflammation of CM in H. pylori-negative individuals is, however, highly controversial. Prevalence of carditis in GERD patients fluctuates between 10 and 97%. Hence, because of its high frequency and low specificity, carditis can currently not be considered as a clinical entity. The role of carditis for the increasing incidence of cancer of the esophagogastric junction requires careful studies that include accurate description of the area with adequate biopsy protocols.