Significance of intestinal metaplasia in different areas of esophagus including esophagogastric junction

Clinicopathologic and molecular analysis of high-grade dysplasia and early adenocarcinoma in short- versus long-segment Barrett esophagus

Barrett esophagus, especially dysplastic Barrett mucosa, has been regarded as a preneoplastic lesion for esophageal adenocarcinoma. However, the etiology and pathogenesis of dysplasia and early adenocarcinoma in short- (SSBE) and long- (LSBE) segment Barrett esophagus have not been studied in detail. The aims of this study were to clarify clinicopathologic and genetic differences between high-grade dysplasia (HGD) and early adenocarcinoma in SSBE versus LSBE. We analyzed the clinicopathologic features from 47 patients (19 SSBE [<3 cm] and 28 LSBE [> or =3 cm]) with esophagectomy for HGD/T1 adenocarcinoma. Allelic losses on chromosomes 3p (FIHT), 5q (APC), 9p (p16), and 17p (p53) were compared in 12 HGD and 9 T1 tumors from 19 cases of SSBE and in 23 HGD and 15 T1 tumors from 28 cases of LSBE. Patients with SSBE were more likely to be smokers than were patients with LSBE (94.7% v 57.1%; P =.004). HGD or T1 tumors arising from SSBE were less likely to show adjoining nondysplastic Barrett mucosa than those from LSBE (73.6% v 100%; P =.02). LSBE more frequently showed a circumferential pattern of Barrett mucosa than did SSBE (96.4% v 47.3%; P =.0002). Chromosomal allelic losses on 3p, 5q, 9p, and 17p were detected in 19% (4 of 21), 43% (15 of 35), 40% (14 of 35), and 48% (16 of 33) of HGD, respectively, and 26% (5 of 19), 35% (8 of 23), 35% (8 of 23), and 57% (13 of 23) of T1 tumor, respectively. There were no significant differences in allelic loss of 3p, 5q, 9p, or 17p in HGD or T1 tumors from SSBE versus LSBE. These results suggest that both HGD and early adenocarcinoma in SSBE and LSBE may occur through similar genetic alterations, whereas there are some clinicopathologic differences between SSBE and LSBE. HUM PATHOL

Short segment Barrett esophagus and specialized columnar mucosa at the gastroesophageal junction

The rising incidence of adenocarcinoma of the esophagus and the gastric cardia has generated interest in the finding of intestinal metaplasia or specialized columnar mucosa in this location. Short segment Barrett esophagus is defined by the presence of columnar-appearing mucosa in the distal esophagus (<3 cm in length) with intestinal metaplasia on biopsy. In contrast, intestinal metaplasia may also be present if biopsy specimens are obtained from a normal-appearing squamocolumnar junction or from the gastric cardia (ie, immediately below the gastroesophageal junction) in the absence of columnar lining of the distal esophagus. This has been termed cardia intestinal metaplasia, gastroesophageal junction intestinal metaplasia, or specialized columnar mucosa at the gastroesophageal junction. This article reviews the currently available data on these rapidly evolving entities of short segment Barrett esophagus and specialized columnar mucosa at the gastroesophageal junction.

Phenotype of Barrett's esophagus and intestinal metaplasia of the distal esophagus and gastroesophageal junction: an immunohistochemical study of cytokeratins 7 and 20, Das-1 and 45 MI

The pathogenesis of short segment Barrett's esophagus (SSBE) and intestinal metaplasia (IM) of the gastroesophageal junction (IMGEJ) are poorly understood. Also, these conditions are difficult to distinguish from one another based solely on endoscopic and pathologic criteria. Therefore, the aim of this study was to evaluate the immunophenotypic features of SSBE and IMGEJ and to compare the results with lesions of known etiologies: long segment BE (LSBE) caused by reflux disease and Helicobacter pylori-induced IM of the gastric antrum (IMGA). Routinely processed mucosal biopsy specimens from 11 patients with LSBE, 17 with SSBE, 10 with IMGEJ, 16 with IMGA, 17 with a normal nonmetaplastic GEJ, and 7 patients with a normal gastric antrum were immunohistochemically stained with monoclonal antibodies to: Das1, an antibody shown to react specifically with colonic goblet cells; 45M1, an antibody that recognizes the M1 gastric mucin antigen; and cytokeratin (CK) 7 and 20, antibodies that have previously been reported to show specific staining patterns in BE versus IMGA. Also evaluated was nonintestinalized mucinous epithelium from LSBE, SSBE, and also the normal GEJ and gastric antrum. LSBE, SSBE, and IMGEJ showed similar prevalences of Das1 (91% versus 88% versus 100%) and 45M1 reactivity (100% versus 100% versus 100%), and a similar pattern of CK7/20 reactivity (diffuse strong CK7 staining of the surface and crypt epithelium, and strong surface and superficial crypt CK20 staining) (91% versus 94% versus 90%). In contrast, although 45M1 reactivity in IMGA (93%) was similar to that of the other three groups, IMGA showed a significantly lower prevalence of Das positivity (13%, p < 0.001), and only a 14% prevalence of the CK7/20 staining pattern that was predominant in the other three groups (p < 0.001). Das1, 45M1, and CK7/20 staining were similar in nonintestinalized "cardia-type" mucinous epithelium from LSBE, SSBE, and the GEJ, but all were distinct from the normal gastric antrum. In summary, the immunophenotypic features of SSBE and IMGEJ are similar and closely resemble those seen in classic LSBE, but are distinct from IMGA. This may indicate that IM in LSBE, SSBE and at the GEJ have similar biologic properties. Based on our data, SSBE and IMGEJ cannot be distinguished on the basis of their immunophenotype.

Gastric cardia intestinal metaplasia: biopsy follow-up of 85 patients

BACKGROUND

Gastric cardia intestinal metaplasia (CIM), denoted by goblet cells is common. The frequency of persistent CIM is unknown.

METHODS

85 patients with CIM and follow-up endoscopies were prospectively identified during the time period of 10/6/94-12/21/97. The presence of goblet cells was the defining feature of CIM, other metaplastic cell types were not evaluated. AU 85 patients initially had biopsies that straddled the squamocolumnar junction (SCJ) showed CIM, an otherwise normal proximal stomach, lower esophagus, and squamocolumnar junction. The SCJ lay within the 2 cm of mucosa immediately proximal to the uppermost gastric fold and overlaid the junction of the tubular esophagus and the saccular dilatation of the stomach in all patients. The patients underwent endoscopy for many reasons. They were randomly identified based on the absence of a hiatal hernia and the presence of CIM.

RESULTS

Ten of the 85 patients had CIM on repeat biopsy. Among patients with no CIM in the first repeat endoscopy, the degree of cardia inflammation decreased between the initial and first repeat endoscopy, whereas there was no change in the amount of inflammation among patients who had CIM in the first repeat endoscopy. The changes in mean inflammation score was significantly different between the two groups (P = .024). Twenty-two patients underwent a second repeat endoscopy and five had a third repeat endoscopy. Including all follow-up biopsies, six of the 85 patients (7%) had CIM. Four patients who did not have CIM on initial repeat endoscopy had CIM on their second repeat endoscopy, probably reflecting sampling issues. None of the biopsies had dysplasia.

CONCLUSIONS

Cardia inflammation is a stimulus for cardia intestinal metaplasia, and a reduction in inflammation may allow the metaplastic mucosa to revert to normal.

The gastric cardia in gastro-oesophageal disease

BACKGROUND

There have been conflicting reports concerning the use of cardia biopsies in screening patients for gastro-oesophageal disease.

AIM

To define the histopathological changes in the gastric cardia of patients with and without gastro-oesophageal disease.

METHODS

Topographically mapped gastric biopsy specimens were obtained from patients with gastro-oesophageal disease and from controls. Biopsies were scored on a visual analogue scale of 0 to 5 for Helicobacter pylori, intestinal metaplasia, pancreatic metaplasia, foveolar hyperplasia, and active inflammation. The presence or absence of cardiac glands was recorded.

RESULTS

Sixty-five patients with gastro-oesophageal disease and 71 controls were examined. Intestinal metaplasia was present in cardia biopsies of 10 patients with gastro-oesophageal disease and 11 controls. Only two patients with gastro-oesophageal disease and intestinal metaplasia in the cardia had no evidence of exposure to H pylori. Intestinal metaplasia was not found in the cardia of those with long segment Barrett's oesophagus. Carditis was strongly associated with active H pylori infection (p = 0.000) and resolved after treatment of the infection. A negative association was present between gastro-oesophageal disease and the presence of cardiac glands in cardiac biopsies (p = 0.003). Pancreatic metaplasia was found in 15 of 65 and foveolar hyperplasia in 19 of 65 cases but neither was related to gastro-oesophageal disease.

CONCLUSION

Intestinal metaplasia in the cardia is uncommon in gastro-oesophageal disease in the absence of H pylori infection. With chronic H pylori infection the junction between the cardia and corpus expands in a cardia-corpal direction.

Cancer of the esophagogastric junction

In the Western world, there has been an alarming rise in the incidence and prevalence of adenocarcinoma arising at the esophagogastric junction during recent decades. Epidemiological, clinical and pathological data support a sub-classification of adenocarcinomas arising in the vicinity of the esophagogastric junction (AEG) into adenocarcinoma of the distal esophagus (Type I), true carcinoma of the cardia (Type II) and subcardial carcinoma (Type III). While most, if not all, adenocarcinomas of the distal esophagus arise from areas with specialized intestinal metaplasia, which develop as a consequence of chronic gastroesophageal reflux, the etiology and pathogenesis of true carcinoma of the gastric cardia and subcardial gastric cancer is not clear at present. Although a subgroup of true carcinomas of the gastric cardia may also develop within short segments of intestinal metaplasia at the esophagogastric junction, a causal relation between these tumors and gastroesophageal reflux has been difficult to establish. Irrespective of the etiology, a complete removal of the primary tumor and its lymphatic drainage has to be the primary goal of any surgical approach to adenocarcinoma of the esophagogastric junction. Our experience in the management of more than 1000 such patients during the past 18 years suggests that an individualized therapeutic strategy oriented by tumor type and stage results in survival rates superior to those reported with a more indiscriminate approach. This individualized strategy prescribes a transmediastinal esophagectomy with lymphadenectomy in the lower posterior mediastinum and along the celiac axis for Type I tumors, extended total gastrectomy with transhiatal resection of the distal esophagus and D2 lymphadenectomy for Type II and Type III tumors, a limited resection of the esophagogastric junction and distal esophagus with interposition of a pedicled jejunal segment for uT1N0 tumors, and neoadjuvant chemotherapy followed by resection for uT3/T4 tumors. Extensive preoperative staging is essential to allow correct selection of the appropriate therapeutic strategy using this tailored approach.

Long-term follow-up of intestinal metaplasia of the gastric cardia

OBJECTIVE

Recent studies have found a relatively high prevalence of gastric cardia intestinal metaplasia in individuals presenting for elective upper endoscopy. It has been hypothesized that this lesion may be a precursor of gastric cardia cancer. Our objective was to identify the incidence of dysplasia in patients with gastric cardia intestinal metaplasia.

METHODS

Twenty-eight patients who had previously been identified with cardia intestinal metaplasia had follow-up examinations performed. None of the patients had dysplasia at the time of diagnosis. All had an examination at 1 yr, and 20 patients had an examination at 3 yr after diagnosis. During follow-up examinations all patients underwent vital staining with methylene blue to help identify areas of intestinal metaplasia in the cardia. Two to four biopsies were taken from blue-stained mucosa. Histological specimens were stained using a combination of hematoxylin and eosin with Alcian blue at pH 2.5.

RESULTS

There were 27 men and one woman with a mean age of 69.8 yr (range, 48-83 yr). The mean length of follow-up was 2.5 yr (range, 12-46 months). Only one patient was diagnosed with dysplasia (low-grade) during the study, for an incidence of 1.4% per yr.

CONCLUSIONS

The prevalence (0%) and incidence (1.4%/yr) of dysplasia in cardia intestinal metaplasia are low. Although further studies are needed, screening and surveillance for gastric cardia intestinal metaplasia is unlikely to be clinically useful for the prevention of gastric cardia cancer.

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

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

Effect of segment length on risk for neoplastic progression in patients with Barrett esophagus

BACKGROUND

The increased risk for esophageal adenocarcinoma associated with long-segment (> or =3 cm) Barrett esophagus is well recognized. Recent studies suggest that short-segment (<3 cm) Barrett esophagus is substantially more common; however, the risk for neoplastic progression in patients with this disorder is largely unknown.

OBJECTIVE

To examine the relation between segment length and risk for aneuploidy and esophageal adenocarcinoma in patients with Barrett esophagus.

DESIGN

Prospective cohort study.

SETTING

University medical center in Seattle, Washington.

PATIENTS

309 patients with Barrett esophagus.

MEASUREMENTS

Patients were monitored for progression to aneuploidy and adenocarcinoma by repeated endoscopy with biopsy for an average of 3.8 years. Cox proportional hazards analysis was used to calculate adjusted relative risks and 95% Cls.

RESULTS

After adjustment for histologic diagnosis at study entry, segment length was not related to risk for cancer in the full cohort (P > 0.2 for trend). When patients with high-grade dysplasia at baseline were excluded, however, a nonsignificant trend was observed; based on a linear model, a 5-cm difference in segment length was associated with a 1.7-fold (95% CI, 0.8-fold to 3.8-fold) increase in cancer risk. Among all eligible patients, a 5-cm difference in segment length was associated with a small increase in the risk for aneuploidy (relative risk, 1.4 [CI, 1.0 to 2.1]; P = 0.06 for trend). A similar trend was observed among patients without high-grade dysplasia at baseline.

CONCLUSIONS

The risk for esophageal adenocarcinoma in patients with short-segment Barrett esophagus was not substantially lower than that in patients with longer segments. Although our results suggest a small increase in risk for neoplastic progression with increasing segment length, additional follow-up is needed to determine whether the patterns of risk occurred by chance or represent true differences. Until more data are available, the frequency of endoscopic surveillance should be selected without regard to segment length.

The gastric cardia: fact or fiction?

OBJECTIVE

It is unclear whether the gastric cardia is present from birth or is metaplastic and develops as a result of gastroesophageal reflux disease. To this end, we evaluated the histology of the entire esophagogastric junction in consecutive pediatric autopsies to determine the presence and extent of cardiac mucosa.

METHODS

The entire esophagogastric junction of 33 consecutive pediatric (< or =18 yr) autopsies was examined. The precise location of the squamocolumnar junction and its relationship to the esophagogastric junction was noted in all cases. Slides were evaluated by two pathologists in a blinded fashion to look for cardiac mucosa, characterized by unequivocal periodic acid-Schiff (PAS)-positive mucous glands in a lobular configuration. Sections from the antrum and esophagogastric junction were examined for the presence of Helicobacter pylori.

RESULTS

Three cases were excluded due to autolysis. The mean age of the 30 remaining patients was 6.3 yr (range: 16 days-18 yr). A regular-appearing squamocolumnar junction was identified at the esophagogastric junction in all 30 cases. Cardiac mucosa was present in all specimens (mean length: 1.8 mm; range: 1.0-4.0 mm), always on the gastric side of the esophagogastric junction. There was no significant association between patient age or gender and length of cardiac mucosa. None of the patients had a known history of gastroesophageal reflux disease or Barrett's esophagus, and none were taking acid-suppressing medications before death. All were negative for Helicobacter pylori by Giemsa stain.

CONCLUSIONS

In an unselected pediatric patient population with little or no propensity for gastroesophageal reflux disease, a short segment of cardiac mucosa was consistently present on the gastric side of the esophagogastric junction, independent of gender or age. These results support the concept that the gastric cardia is present from birth as a normal structure.

Epidemiology of esophageal cancer, especially adenocarcinoma of the esophagus and esophagogastric junction

The incidence of adenocarcinoma of the esophagus and esophagogastric junction (EGJ) has been increasing over the past 15 years in western countries. Surgical series and population-based studies show that, by 1994, adenocarcinomas of the esophagus accounted for half of all esophageal cancer among white men. The causes of this increase in incidence remain to be elucidated. Esophageal adenocarcinomas and a portion of EGJ adenocarcinomas arise from long and short segments of specialized intestinal metaplasia (Barrett's esophagus). The prevalence of long segments of Barrett's esophagus (> 3 cm) in patients having endoscopy for reflux symptoms is 3%, and 1% in those undergoing endoscopy for any clinical indication. However, a silent majority of patients with Barrett's esophagus remain unrecognized in the general population and may not be diagnosed unless adenocarcinoma develops. Recent studies document a rise in the diagnosis of specialized intestinal metaplasia of the cardia. Nearly all these patients have associated carditis, and Helicobacter pylori infection has been linked to this condition. The possible origin of EGJ adenocarcinomas in the sequence carditis--specialized intestinal metaplasia needs to be clarified. Smoking and obesity are additional risk factors for adenocarcinoma of the esophagus and EGJ. Current data does not confirm H. pylori as a risk factor for cancer of the EGJ.

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

OBJECTIVES

A distinctive type of columnar epithelium with intestinal metaplasia is considered diagnostic for Barrett's esophagus. The neoplastic potential of pancreatic metaplasia at the esophagogastric junction is unknown. The aims of the present study were: 1) to characterize both forms of metaplasia at the esophagogastric junction, and to estimate their prevalence; 2) to investigate c-erbB-2 expression and K-ras mutations in pancreatic metaplasia; and 3) to study the relationship between metaplasia, inflammatory changes in the cardiac mucosa, and presence of H. pylori.

METHODS

A total of 76 esophagogastrectomy specimens of patients with a normally located squamocolumnar junction, were investigated immunohistochemically. K-ras mutations were evaluated using PCR.

RESULTS

Intestinal metaplasia in the cardia was found in 12% of patients: six complete-type, and three incomplete-type. Pancreatic metaplasia was demonstrated in 14% of patients, and neither c-erbB-2 expression nor K-ras mutations were found. Intestinal and pancreatic metaplasia were associated with mucosal inflammation. In contrast to generalized gastritis, isolated "carditis" was not associated with H. pylori infection.

CONCLUSIONS

When intestinal metaplasia occurs in a biopsy from the esophagogastric junction, it is not necessarily a marker for Barrett's esophagus. No indication was found that pancreatic metaplasia has neoplastic potential. Both forms of metaplasia reflect mucosal inflammation. Carditis may be a distinct inflammatory condition of the gastric mucosa that is not related to H. pylori infection.

The esophageal Z-line appearance correlates to the prevalence of intestinal metaplasia

BACKGROUND

Intestinal metaplasia at the gastroesophageal junction is associated with Barrett esophagus, gastric cardiac cancer, and gastritis. The aim of this study was to determine the prevalence of intestinal metaplasia among patients with symptoms suggestive of gastroesophageal reflux disease (GERD) and to study clinical, endoscopic, and histologic associations with intestinal metaplasia at the squamocolumnar junction.

METHODS

One hundred and eighty-six patients with symptoms indicating gastroesophageal reflux were included in the study. A new classification of the Z-line appearance was used.

RESULTS

The Z-line appearance was found to correlate with the prevalence of intestinal metaplasia at the squamocolumnar junction (P = 0.0001). Intestinal metaplasia at the squamocolumnar junction was found in 15.0% of the patients. There was a statistically significant association between intestinal metaplasia at the squamocolumnar junction and tongues of columnar epithelium at the Z-line (P = 0.020), intestinal metaplasia in the cardia (P = 0.020), positive CLO test (P = 0.026), smoking (P = 0.041), and age (P = 0.050). There was no association with endoscopic or histologic signs of esophagitis or with the severity or duration of GERD symptoms.

CONCLUSION

Intestinal metaplasia at the squamocolumnar junction correlates with the Z-line appearance, which would justify a new classification.

Chronic inflammation at the gastroesophageal junction (carditis) appears to be a specific finding related to Helicobacter pylori infection and gastroesophageal reflux disease. The Central Finland Endoscopy Study Group

OBJECTIVE

The clinical significance of chronic inflammation at the gastroesophageal junction (carditis) is unknown: it may be associated with Helicobacter pylori (H. pylori) gastritis or with gastroesophageal reflux disease (GERD). We aimed to examine the association between carditis and H. pylori gastritis and endoscopic erosive esophagitis.

METHODS

One thousand and fifty-three patients undergoing gastroscopy were enrolled in the study. Biopsy specimens were obtained from gastric antrum and corpus, immediately distal to normal-appearing squamocolumnar junction and distal esophagus.

RESULTS

Chronic inflammation at the gastroesophageal junctional mucosa (carditis) was detected in 790 (75%) of 1053 patients. The male:female ratio of the carditis group was 1:1.5 and of the noncarditis group 1:1.6 (p = 0.6). The mean age of the carditis group was 58.7 yr (95% confidence interval [CI], 57.6-59.9) and of the noncarditis group, 52.6 yr (95% CI, 50.7-54.6, p < 0.001). Of the carditis group (N = 790), 549 (69%) had chronic gastritis (70% H. pylori positive) and 241 (31%) had normal gastric histology. In multivariate analyses, the only risk factor for carditis in subjects with chronic gastritis was H. pylori infection (odds ratio [OR], 2.9; 95% CI, 1.6-5.0), whereas the independent risk factor for carditis in subjects with histologically normal stomach was endoscopic erosive esophagitis (OR, 1.8; 95% CI, 1.1-3.1). The prevalence of complete intestinal metaplasia (IM) in the gastric cardia mucosa was 7% in the noncarditis group, 19% (p < 0.001) in the carditis group with chronic gastritis, and 10% (p = 0.3) in the carditis group with normal stomach. The respective prevalences of incomplete IM were 3%, 12% (p < 0.001), and 12% (p < 0.001). Among carditis patients with normal stomach histologically (N = 241), those with complete and/or incomplete IM (N = 49) were older than those with carditis only (63.6 yr [95% CI, 59.9-67.2] vs 51.4 yr [95% CI, 48.9-53.9]; p < 0.001).

CONCLUSIONS

Two dissimilar types of chronic inflammation of the gastric cardia mucosa seem to occur, one existing in conjunction with chronic H. pylori gastritis and the other with normal stomach and erosive GERD. Most cases of chronic gastric cardia inflammation and intestinal metaplasia are detected in patients with chronic H. pylori gastritis.

Surgical resection for cancer of the cardia

From the pathogenic and therapeutic point of view, adenocarcinomas of the esophagogastric junction (AEG) should be classified into adenocarcinoma of the distal esophagus (Type I), true carcinoma of the cardia (Type II), and subcardial carcinoma (Type III). This classification can be easily performed by summarizing the information available from contrast radiography, endoscopy, and intra-operative findings; it allows comparison of data between various centers and facilitates the choice of surgical therapy. A complete removal of the primary tumor and its lymphatic drainage has to be the primary goal of any surgical approach to adenocarcinoma of the esophagogastric junction. In patients with potentially resectable, true carcinoma of the cardia (AEG Type II), this can be achieved by a total gastrectomy with transhiatal resection of the distal esophagus and en bloc removal of the lymphatic drainage in the lower posterior mediastinum and along the celiac axis and superior border of the pancreas. This approach is associated with lower morbidity and provides equal long-term survival as compared to the more radical transmediastinal or abdominothoracic esophagogastrectomy. Whether a routine splenectomy for lymphadenectomy in the splenic hilus offers a survival benefit in these patients is questionable. In patients with early tumors staged as uT1 on pre-operative endosonography, a limited resection of the proximal stomach, cardia, and distal esophagus with interposition of a pedicled isoperistaltic jejunal segment appears justified since this procedure allows a complete tumor removal with adequate lymphadenctomy and offers excellent functional results. Multimodal therapy with pre-operative polychemotherapy or combined radio-chemotherapy appears to offer a significant survival benefit in patients with locally advanced tumors. With this tailored approach, extensive pre-operative staging becomes mandatory for an adequate selection of the appropriate therapeutic concept.

Molecular evolution of the metaplasia-dysplasia-adenocarcinoma sequence in the esophagus

The incidence of adenocarcinoma of the esophagus has been increasing in developing countries over the last three decades and probably reflects a genuine increase in the incidence of its recognized precursor lesion, Barrett's metaplasia. Despite advances in multimodality therapy, the prognosis for invasive esophageal adenocarcinoma is poor. An improved understanding of the molecular biology of this disease may allow improved diagnosis, therapy, and prognosis. We focus on recent developments in the molecular and cell biology of Barrett's metaplasia, a heterogeneous lesion affecting the transitional zone of the gastro-esophageal junction whose associated molecular alterations may vary both in nature and temporally. Early premalignant clones produce biological and genetic heterogeneity as seen by multiple p53 mutations, p16 mutations, aneuploidy, and abnormal methylation resulting in stepwise changes in differentiation, proliferation, and apoptosis, allowing disease progression under selective pressure. Abnormalities in expression of growth factors of the epidermal growth factor family and cell adhesion molecules, especially cadherin/catenin complexes, may occur early in invasion. Exploitation of these molecular events may lead to a more appropriate diagnosis and understanding of these lesions in the future.

Characteristics of intestinal metaplasia in the gastric cardia

OBJECTIVE

Intestinal metaplasia of the gastroesophageal junction is frequently grouped together with Barrett's esophagus. The area of the gastroesophageal junction is comprised of the distal esophagus and the gastric cardia. The aim of the present study was to assess whether intestinal metaplasia in the distal esophagus and gastric cardia represent two different entities with a different set of risk factors.

METHODS

Patients presenting for elective upper endoscopy were enrolled into a prospective study. The presence of gastritis and intestinal metaplasia was evaluated in gastric biopsies taken from the antrum, corpus, and cardia. Barrett's esophagus was defined by the presence of any length of columnar mucosa above the gastroesophageal junction.

RESULTS

Of 302 patients, 50 patients had intestinal metaplasia of the gastric cardia, 73 Barrett's esophagus, and 116 erosive esophagitis. Men were more prone than women to develop Barrett's esophagus or erosive esophagitis. Both conditions were also more common among whites than nonwhites. Smoking was particularly common among patients with Barrett's esophagus. Patients with cardiac intestinal metaplasia did not share these demographic characteristics. The prevalence of daily reflux symptoms, erosive esophagitis, and Barrett's esophagus was similar among patients both with and without cardiac intestinal metaplasia. However, atrophy and intestinal metaplasia of the gastric antrum and corpus were found more frequently among patients with than without cardiac intestinal metaplasia.

CONCLUSIONS

Intestinal metaplasia of the gastric cardia is different from Barrett's esophagus. Although cardiac intestinal metaplasia is closely associated with signs of gastritis in other parts of the stomach, gastroesophageal reflux disease does not seem to be a risk factor. A diagnosis of Barrett's esophagus should not be made based on the presence of intestinal metaplasia within the cardiac portion of the gastroesophageal junction.

Specialized intestinal metaplasia, dysplasia, and cancer of the esophagus and esophagogastric junction: prevalence and clinical data

BACKGROUND & AIMS

Adenocarcinoma of the esophagus and esophagogastric junction (EGJ) is increasing, the earliest lesion being specialized intestinal metaplasia (SIM). This study determined the prevalence and demographic features of patients with SIM, dysplasia, and cancer in the esophagus and EGJ.

METHODS

Two antegrade biopsy specimens were taken distal to the squamocolumnar junction (SCJ) and any tongues of pink mucosa proximal to the SCJ. Patients were categorized endoscopically and histologically as having long-segment (LSBE) or short-segment Barrett's esophagus (SSBE), EGJ-SIM, or a normal EGJ.

RESULTS

Of 889 patients studied, 56 were undergoing esophagoduodenoscopy screening or surveillance and were not included in the prevalence calculation. The overall prevalence of SIM was 13.2%, with 1.6% LSBE, 6.0% SSBE, and 5.6% EGJ-SIM. Dysplasia or cancer was noted in 31% of LSBE, 10% of SSBE, and 6.4% of EGJ-SIM patients (P </= 0.043). Two cancers were associated with LSBE, 1 with SSBE, and 1 with EGJ-SIM. Patients with LSBE and SSBE were predominantly white (P </= 0.001), male (P </= 0. 009), and smokers (P </= 0.004), with LSBE patients having a longer history of heartburn (P </= 0.009). In contrast, patients with EGJ-SIM were similar in gender and ethnicity to the reference group, tended to be older (P </= 0.05), drank less alcohol (P </= 0.02), and had a higher prevalence of Helicobacter pylori infection (P </= 0.05).

CONCLUSIONS

The prevalence of SSBE and EGJ-SIM is similar, but each entity is 3.5 times more prevalent than LSBE. However, the prevalence of dysplasia in LSBE is 2 times greater than in SSBE and 4 times greater than in EGJ-SIM. Demographically, EGJ-SIM patients are different from patients with Barrett's esophagus and have a higher prevalence of H. pylori infection. These data help to explain the increasing incidence of adenocarcinoma of the distal esophagus and EGJ.

Barrett's esophagus: the long and the short of it

Specialized intestinal epithelium occurs more frequently at the gastroesophageal junction than previously anticipated. It can occur either within tongues of mucosa (short segment Barrett's) or just beneath a normal z-line (intestinal metaplasia at the gastroesophageal junction). Whether the etiopathogenesis and the natural history of these two conditions are the same is as yet unclear. The role of gastroesophageal reflux disease (GERD), Helicobacter pylori, and inflammation at the gastroesophageal junction in the pathogenesis of short segment Barrett's and intestinal metaplasia at the gastroesophageal junction needs to be carefully documented. Intestinal metaplasia at the gastroesophageal junction, short segment Barrett's, and Barrett's may represent a continuum of the same disease process. Recent evidence suggests, however, that short segment Barrett's shares similar characteristics with Barrett's but may be distinct from intestinal metaplasia at the gastroesophageal junction. It is conceivable that short segment Barrett's may remain steady or even regress if and when the noxious influence wanes but, with continuing stimulation, short segment Barrett's may lengthen further to become what we observe to be Barrett's. If correct, endogenous or exogenous factors that induce progression need to be identified. Acid and bile reflux and H. pylori are possible candidates acting either singly or synergistically. Finally, the true neoplastic potential of short segment Barrett's needs clarification.

Short segment Barrett's esophagus--the need for standardization of the definition and of endoscopic criteria

There has been a recent increase in abstracts and publications reporting intestinal metaplasia in the distal esophagus and cardia. The terms "short segment Barrett's esophagus," "intestinal metaplasia of the esophagogastric junction," and "intestinal metaplasia of the cardia" are being used to describe either similar or different entities. This review article deals with the current data on these issues, the definition of short segment Barrett's esophagus including the endoscopic and histologic criteria, the rationale for separating short segment Barrett's esophagus from intestinal metaplasia of the cardia, and a simple classification of intestinal metaplasia.

The prevalence of intestinal metaplasia in patients with and without peptic strictures

OBJECTIVE

Several studies suggest that patients with esophageal peptic strictures have a high prevalence of Barrett's esophagus. However, these studies did not include appropriate control groups, were retrospective in nature, or did not strictly define Barrett's esophagus. Our aim was to compare the prevalence of Barrett's esophagus in patients with and without gastroesophageal reflux disease strictures in a prospective study.

METHODS

Seventy-nine patients referred for endoscopy for gastroesophageal reflux disease symptoms were evaluated. We collected demographic information and an esophageal symptom assessment. Biopsy specimens were obtained from peptic strictures, Schatzki rings, or from any areas of columnar-lined esophagus or mucosal injury. Barrett's esophagus was strictly defined as the presence of intestinal metaplasia from tubular esophagus.

RESULTS

There were 46 patients without strictures and 28 patients with peptic strictures. Five patients had Schatzki's rings. The prevalence of intestinal metaplasia was 23.9% in patients without strictures, and 25% in patients with peptic strictures (p = NS). There was no difference in prevalence of short- or long-segment Barrett's esophagus between the groups. Patients with strictures were older than patients without strictures (mean age 58.9 vs 48.6 yr), and more likely to have mucosal injury (50% vs 26.1%). Otherwise, there were no significant differences with regards to gender, race, heartburn duration or frequency.

CONCLUSIONS

Barrett's esophagus, as defined by the presence of intestinal metaplasia in the tubular esophagus, is equally common in patients with and without peptic strictures. There does not appear to be an association between Barrett's esophagus and peptic strictures.

Racial differences in the histology, location, and risk factors of esophageal cancer

Although esophageal cancer is uncommon in the united states, its high mortality rate and recent increased incidence make it an important malignancy. Because there appears to be significant racial variation in the types of esophageal cancer, we examined a group of black patients with esophageal cancer and compared their risk factors, histology, and location with those of a cohort of white patients with esophageal cancer seen during the same period. We retrospectively reviewed patients with esophageal cancer seen at three major hospitals in Atlanta, Georgia from January 1990 to April 1996. Patients of races other than white or black were excluded from this study, the esophagus was separated into upper, middle, and lower thirds by defined criteria. Of the eligible 234 patients, 129 were black and 105 were white. In blacks with esophageal cancer, squamous cell cancer was the predominant type (92%), and adenocarcinoma was infrequent in whites, adenocarcinoma was more common than squamous cell cancer (66% vs. 32%). Although Barrett's esophagus was distinctly uncommon, smoking and alcohol consumption were significantly more common in blacks. Only 43% of the patients with adenocarcinoma had evidence of barrett's esophagus, all adenocarcinomas were located in the lower third of the esophagus. There appear to be significant racial differences in the types, risk factors, and location of esophageal cancer. Adenocarcinoma and Barrett's esophagus are uncommon in blacks.