Cytokeratin subsets can reliably distinguish Barrett's esophagus from intestinal metaplasia of the stomach

MODIFIED CLASSIFICATION FOR ADENOCARCINOMA OF THE GASTRO-OESOPHAGEAL JUNCTION

BACKGROUND

Incidence of the gastro-oesophageal junction adenocarcinoma is increasing. Siewert's classification subdivides junctional adenocarcinomas anatomically. Cytokeratin (CK) 7 and 20 immunophenotypes differentiate Barrett's intestinal metaplasia (IM) from gastric IM. Comparing CK immunostaining with Siewert's classification may establish tumour origin and influence surgical choice.

METHODS

In this experimental study, 57 patients with gastro-oesophageal junction adenocarcinoma were subdivided endoscopically into 15 type 1, 26 type 2 and 16 type 3 adenocarcinomas. Representative biopsies were immunostained for CK7 and CK20.

RESULTS

Intestinal metaplasia was associated with type 1 adenocarcinoma in 12 of 15 patients, 80%; with type 2 in 13 of 26 patients, 50% and type 3 in 6 of 16 patients, 37.5%. All type 1 patients showed Barrett's CK7/CK20 phenotype within IM; type 2 a mixture: 69% (n=9) Barrett's CK7/CK20 and 31% (n=4) gastric CK7/CK20 whereas type 3 patients had a gastric CK7/CK20 pattern in 83% (n=5). Immunostaining within the adenocarcinoma was variable.

CONCLUSION

Siewert's type 1 adenocarcinomas express Barrett's CK7/CK20 pattern, type 3 a gastric CK7/CK20 pattern and type 2 tumours a mixture of Barrett's and gastric CK7/CK20 patterns within associated IM. CK immunostaining may refine Siewert's classification into oesophageal type 1 or gastric type 2 adenocarcinoma with IM.

Downregulation of p63 upon exposure to bile salts and acid in normal and cancer esophageal cells in culture

p63 is a member of the p53 protein family that regulates differentiation and morphogenesis in epithelial tissues and is required for the formation of squamous epithelia. Barrett's mucosa is a glandular metaplasia of the squamous epithelium that develops in the lower esophagus in the context of chronic, gastroesophageal reflux and is considered as a precursor for adenocarcinoma. Normal or squamous cancer esophageal cells were exposed to deoxycholic acid (DCA, 50, 100, or 200 microM) and chenodeoxycholic and taurochenodeoxycholic acid at pH 5. p63 and cyclooxygenase-2 (COX-2) expressions were studied by Western blot and RT-PCR. DCA exposure at pH 5 led to a spectacular decrease in the levels of all isoforms of the p63 proteins. This decrease was observed within minutes of exposure, with a synergistic effect between DCA and acid. Within the same time frame, levels of p63 mRNA were relatively unaffected, whereas levels of COX-2, a marker of stress responses often induced in Barrett's mucosa, were increased. Similar results were obtained with chenodeoxycholic acid but not its taurine conjugate at pH 5. Proteasome inhibition by lactacystin or MG-132 partially blocked the decrease in p63, suggesting a posttranslational degradation mechanism. These results show that combined exposure to bile salt and acid downregulates a critical regulator of squamous differentiation, providing a mechanism to explain the replacement of squamous epithelium by a glandular metaplasia upon exposure of the lower esophagus to gastric reflux.

Bone morphogenetic protein 4 expressed in esophagitis induces a columnar phenotype in esophageal squamous cells

BACKGROUND & AIMS

Barrett's esophagus (BE) is a metaplastic condition in which normal squamous esophageal epithelium is replaced by columnar epithelium. It is proposed that one of the possible mechanisms is dedifferentiation of squamous epithelium into columnar epithelium. The pathophysiology through which this metaplasia occurs is unknown. A recent study by serial analysis of gene expression showed that bone morphogenetic protein 4 (BMP-4) is uniquely expressed in BE. In this study, the role of the BMP pathway in the metaplastic transformation of normal squamous cells into columnar cells was examined.

METHODS

Tissues from patients with esophagitis and BE and in an esophagitis-BE rat model were examined for the activation of the BMP pathway. Short-term cultures of primary normal squamous esophageal cells were treated with BMP-4, and cell biological changes were examined by Western blot analysis, immunohistochemistry, and microarrays.

RESULTS

In both human and rat tissues, the BMP pathway proved to be activated in esophagitis and BE. Upon incubation of squamous cell cultures with BMP-4, the cytokeratin expression pattern showed a shift that was consistent with columnar epithelium. Involvement of the BMP pathway was suggested by up-regulation of Phosphorylated-Smad 1/5/8 (P-Smad 1/5/8) that was effectively blocked by Noggin, a BMP antagonist. Comparison of the gene expression profiles of squamous cells, BMP-4-treated squamous cells, and BE cells showed a significant shift in the profile of the BMP-4-treated squamous cells toward that of the cultured BE cells.

CONCLUSIONS

These results suggest that the BMP pathway could play a role in the transformation of normal esophageal squamous cells into columnar cells.

The use of cytokeratin stain to distinguish Barrett's esophagus from contiguous tissues: a systematic review

Our objective was to systematically review the existing literature regarding the use of cytokeratin (CK) stain in differentiating Barrett's esophagus (BE) from tissues of the gastric cardia, corpus, or antrum, with or without intestinal metaplasia (IM). Pubmed was searched for full publications in English (1983-2005) addressing the use of CK for differentiation of BE from contiguous tissues. Information was collected on the study sample, blinding, the methods used for CK staining, and for defining and applying the gold standard tests. Test characteristics were obtained or calculated. Sixteen studies (containing 46 comparisons) met the inclusion and exclusion criteria. Immunostaining for CK 7 and 20 was generally highly specific in distinguishing long-segment BE from antrum IM, fundus IM, or noncardiac gastric IM; 27 comparisons showed statistically significant differences. However, only 8 of 15 comparisons (6 of 12 studies) reported significant differences in CK staining patterns between BE and gastric cardia IM with a high sensitivity (89%-100%) and specificity (83%-100%) for long-segment BE and lower estimates for short-segment BE, while the other seven comparisons showed no significant differences and a very low sensitivity. Examination by a blinded pathologist was reported in five of six positive studies and in only one of six of the negative studies. In addition, variation in the patient populations, use of surgical resection versus endoscopic biopsies, and biopsy sampling technique in endoscopic studies may have accounted for these differences. Finally, two studies did not find significant differences in CK staining patterns between BE and normal cardiac mucosa. In conclusions, CK immunostaining has not performed well in differentiating BE, especially short-segment BE, from cardia IM. There seems to be a spectrum bias where the accuracy varies with different tested populations. CK immunostaining distinguished well between BE and IM in noncardiac segments of the stomach; however, these comparisons are not clinically relevant.

Immunopathological Patterns of the Stomach in Adenocarcinoma of the Esophagus, Cardia, and Gastric Antrum: Gastric Profiles in Siewert Type I and II Tumors

BACKGROUND

The morphologic and immunohistochemical profiles of gastric mucosa and of the tumor were assessed in Siewert type I, type II, and gastric antrum adenocarcinomas.

METHODS

Sixty-two patients, prospectively operated upon, were included in the study: 37 type II, 15 type I, and 10 antrum adenocarcinoma. Samples of the tumor, the surrounding area, and the gastric corpus and antrum were analyzed histologically, and immunostained for cytokeratins (CK)7/20 (staining positive for cells labeled > or = 50%).

RESULTS

Among the 37 type II adenocarcinomas were the following: (1) 13 of 37 (35%) had intestinal metaplasia (IM) in the stomach; (2) 24 of 37 (65%) did not show IM at any level; (3) 34 of 37 (92%) had Helicobacter pylori (HP) infection; (4) 13 of 37(35%) had CK7/20 expression of "Barrett's type" (CK7+/20-); 24 of 37 (65%) had a "no Barrett's type" profile (10 of 37 with CK7-/CK20+ and 14 of 37 with CK7+/CK20+); (5) 100% showed the same CK immunoprofile, both in IM and adenocarcinoma (measure of agreement k = 1, p = 0.000). Type I adenocarcinomas showed the following: (1) 87.5% CK Barrett's type, both in the tumor, and in the surrounding IM; (2) 100% gastric samples devoid of both IM and HP infection. Comparison between CK immunoprofiles in type I and type II tumors showed a difference within the two groups (p = 0.002). One hundred percent of antrum adenocarcinomas showed a no Barrett's type CK profile, both in the tumor and in the IM of the entire stomach.

CONCLUSIONS

Data suggest that type II adenocarcinoma cannot be always considered a gastroesophageal reflux disease-related tumor; other pathogenetic pathways should be taken into consideration.

CDX2 expression in columnar metaplasia of the remnant esophagus in patients who underwent esophagectomy

BACKGROUND

Patients who have undergone esophagectomy with gastric tube reconstruction often have complaints of gastro-esophageal reflux. A subset of these patients will develop columnar epithelium in the remnant esophagus, which can be of the gastric or intestinal type (Barrett esophagus).

GOALS

To determine whether gastric-type mucosa (GM) in the esophagus is a precursor stage of intestinal metaplasia (IM).

STUDY

The medical records of 613 patients having undergone esophagectomy were reviewed for the endoscopic presence of segments with columnar mucosa in the remnant esophagus. Of them, 45 patients underwent endoscopic follow-up at least 6 months after resection. The presence of IM in the remnant esophagus was determined histologically in archival biopsy samples. Intestinal characteristics were identified by immunohistochemistry for CDX2, MUC2, and cytokeratins 7 and 20. CDX2 transcription was assessed by reverse transcription polymerase chain reaction.

RESULTS

In 18 of 45 patients (40%) GM was identified, and 7 of these patients also had foci of IM. CDX2 and MUC2 expression was observed in IM, and in 2 patients, CDX2 expression was also observed in gastric-type glands at a distance from intestinal glands. CDX2 transcription was identified in 2 patients without IM.

CONCLUSIONS

In the majority of patients after esophageal resection, expression of CDX2 and MUC2 in the remnant esophagus was only detectable in IM, but CDX2 was also observed in 4 cases with only GM. This could indicate that induction of formation of GM and IM may share a common pathway, eventually leading to the development of specialized intestinal epithelium.

Molecular defense mechanisms of Barrett's metaplasia estimated by an integrative genomics

Barrett's esophagus is characterized by the replacement of squamous epithelium with specialized intestinal metaplastic mucosa. The exact mechanisms of initiation and development of Barrett's metaplasia remain unknown, but a hypothesis of "successful adaptation" against noxious reflux components has been proposed. To search for the repertoire of adaptation mechanisms of Barrett's metaplasia, we employed high-throughput functional genomic and proteomic methods that defined the molecular background of metaplastic mucosa resistance to reflux. Transcriptional profiling was established for 23 pairs of esophageal squamous epithelium and Barrett's metaplasia tissue samples using Affymetrix U133A 2.0 GeneChips and validated by quantitative real-time polymerase chain reaction. Differences in protein composition were assessed by electrophoretic and mass-spectrometry-based methods. Among 2,822 genes differentially expressed between Barrett's metaplasia and squamous epithelium, we observed significantly overexpressed metaplastic mucosa genes that encode cytokines and growth factors, constituents of extracellular matrix, basement membrane and tight junctions, and proteins involved in prostaglandin and phosphoinositol metabolism, nitric oxide production, and bioenergetics. Their expression likely reflects defense and repair responses of metaplastic mucosa, whereas overexpression of genes encoding heat shock proteins and several protein kinases in squamous epithelium may reflect lower resistance of normal esophageal epithelium than Barrett's metaplasia to reflux components. Despite the methodological and interpretative difficulties in data analyses discussed in this paper, our studies confirm that Barrett's metaplasia may be regarded as a specific microevolution allowing for accumulation of mucosal morphological and physiological changes that better protect against reflux injury.

Barrett's oesophagus?a pathologist's view

Barrett's oesophagus, a precancerous condition for oesophageal adenocarcinoma, detected on endoscopy and confirmed on histology, shows intestinal metaplasia of the lower oesophagus. The significance of microscopic foci of intestinal metaplasia at the gastro-oesophageal junction, corresponding either to so-called 'ultrashort' segment Barrett's oesophagus, or to carditis with intestinal metaplasia, is still a matter of debate. The surveillance of patients with Barrett's oesophagus is still based on systematic biopsy sampling of Barrett's mucosa on endoscopy, looking for dysplasia. Although well-established classifications of dysplasia are now used by most pathologists, there remain numerous problems with this subjective marker (sampling, diagnostic reproducibility, natural history, etc). Therefore, many alternative biomarkers have been proposed, but only DNA aneuploidy, proliferation markers and p53 loss of heterozygosity/overexpression have been shown to be of some use at the present time. Some endoscopic improvements already allow a better selection of biopsies, and it may be that in future new technologies will allow 'virtual biopsies'. On the other hand, the role of pathologists now extends to the evaluation of new therapeutic modalities of early neoplastic lesions in Barrett's oesophagus, especially endoscopic mucosal resection.

Short segment Barrett's esophagus and distal gastric intestinal metaplasia

BACKGROUND

Short segment Barrett's esophagus is defined by the presence of <3 cm of columnar-appearing mucosa in the distal esophagus with intestinal metaplasia on histophatological examination. Barrett's esophagus is a risk factor to develop adenocarcinoma of the esophagus. While Barrett's esophagus develops as a result of chronic gastroesophageal reflux disease, intestinal metaplasia in the gastric cardia is a consequence of chronic Helicobacter pylori infection and is associated with distal gastric intestinal metaplasia. It can be difficult to determine whether short-segment columnar epithelium with intestinal metaplasia are lining the esophagus (a condition called short segment Barrett's esophagus) or the proximal stomach (a condition called intestinal metaplasia of the gastric cardia).

AIMS

To study the association of short segment Barrett's esophagus (length <3 cm) with gastric intestinal metaplasia (antrum or body) and infection by H. pylori.

PATIENTS AND METHODS

Eight-nine patients with short segment columnar-appearing mucosa in the esophagus, length <3 cm, were studied. Symptoms of gastroesophageal reflux disease were recorded. Biopsies were obtained immediately below the squamous-columnar lining, from gastric antrum and gastric corpus for investigation of intestinal metaplasia and H. pylori.

RESULTS

Forty-two from 89 (47.2%) patients were diagnosed with esophageal intestinal metaplasia by histopathology. The mean-age was significantly higher in the group with esophageal intestinal metaplasia. The two groups were similar in terms of gender (male: female), gastroesophageal reflux disease symptoms and H. pylori infection. Gastric intestinal metaplasia (antrum or body) was diagnosed in 21 from 42 (50.0%) patients in the group with esophageal intestinal metaplasia and 7 from 47 (14.9%) patients in the group with esophageal columnar appearing mucosa but without intestinal metaplasia.

CONCLUSION

Intestinal metaplasia is a frequent finding in patients with <3 cm of columnar-appearing mucosa in the distal esophagus. In the present study, short segment intestinal metaplasia in the esophagus is associated with distal gastric intestinal metaplasia. Gastroesophageal reflux disease symptoms and H. pylori infection did not differ among the two groups studied.

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.

Pathologic Risk Factors of Adenocarcinoma of the Gastric Cardia and Gastroesophageal Junction

Available evidence supports the existence of two major pathways of neoplastic development in the gastroesophageal region: the Barrett pathway, related to gastroesophageal reflux disease, and the gastric pathway, related to Helicobacter pylori infection. The existence of an independent junctional pathway is questionable, and gastroesophageal junction adenocarcinomas share features of esophageal and gastric adenocarcinomas. It has been impossible to accommodate all data that are provided by different levels and tools of observation in tumors that develop in the gastroesophageal region in a single, coherent classification. That is why the stratification of pathologic risk in such tumors, and their respective precursors, incorporates features from topography, histology, immunohistochemistry, and molecular pathology.

Pathology of the gastroesophageal junction

The gastroesophageal junction (GEJ) is a poorly defined anatomic area that represents the junction etween the distal esophagus and the proximal stomach (cardia). The true anatomic GEJ corresponds to the most proximal aspect of the gastric folds, which represents an endoscopically apparent transition oint in most individuals. Many, if not most, adults, particularly those with either physiologic or logic GERD, have a proximally displaced Z-line indicating that the histologic squamocolumnar nction (SCJ) is located above the anatomic GEJ. The histologic characteristics of short segments of columnar mucosa located above the anatomic GEJ in these individuals are similar to the gastric cardia, ng composed of either pure mucous glands or mixed mucous glands/oxyntic glands. Although controversial, some authors believe that the cardia is normally composed, at birth, of surface mucinous columnar epithelium and underlying oxyntic glands identical to the gastric corpus, whereas others maintain that the true anatomic cardia is normally composed of mucinous columnar epithelium with underlying mucous glands or mixed mucous and oxyntic glands. However, the preponderance of evidence supports the latter theory and that the length of mucosa composed of either mucous, or mixed mucous glands/oxyntic glands, increases with age and is presumed to be related to ongoing GERD. Inflammation of the true gastric cardia (carditis), which is most often due to H. pylori infection, is difficult to distinguish from columnar metaplasia of the distal esophagus secondary to GERD. From a pathologist's perspective, the differential diagnosis of true gastric carditis from esophageal columnar metaplasia of the distal esophagus in GEJ biopsies is difficult, but a variety of clinical, pathologic, and immunohistochemical methods can be used to help separate these two disorders. Nearly one-third of patients who present for upper GI endoscopy without endoscopic evidence of BE reveal foci of intestinal metaplasia in the GEJ. There are some studies to suggest that the risk of dysplasia and cancer is different in patients with intestinal metaplasia in the cardia related to H. pylori infection versus those with metaplastic columnar epithelium in the distal esophagus related to GERD. Chronic inflammation is generally considered the predominant underlying stimulus for the development of columnar metaplasia in the GEJ, regardless of the etiology. Columnar metaplasia and intestinal metaplasia in the distal esophagus represents a squamous to columnar cell transition and there is some evidence that this occurs through an intermediate, or transitional, phase of intestinalization termed multilayered epithelium. In contrast, intestinal metaplasia that develops in the true gastric cardia secondary to H. pylori infection represents a columnar to columnar metaplastic reaction. This review will focus on the clinical, pathologic, and pathogenetic aspects of GERD and H. pylori-induced inflammation of the GEJ region.

Barrett's esophagus: pathologic considerations and implications for treatment

Barrett's esophagus (BE) is a complication of chronic reflux that results in the replacement of esophageal squamous epithelium with columnar epithelium. BE is endoscopically recognized and pathologically confirmed. The presence of goblet cells is diagnostic. The pathologist must also determine if dysplasia or invasive cancer is present. Acceptable terms for dysplasia are no dysplasia, indefinite for dysplasia, low-grade dysplasia (LGD), or high-grade dysplasia (HGD). It can be difficult to differentiate HGD from intramucosal cancer (IMC) in an endoscopic biopsy specimen. Treatment based on this differentiation is problematic. Indications for treatment of BE are similar to those of patients without BE. Treatment will not cause clinically significant regression of BE or prevent progression to cancer. Cancer development following successful antireflux surgery is uncommon.

A "crackleware" oesophagus

This case report describes a 70 year old woman with excessive diffuse keratinisation of the oral cavity and oesophagus harbouring a squamous cell carcinoma. This excessive diffuse keratinisation of normally non-keratinised squamous epithelium could not be identified in normally non-keratinised epithelia in other parts of the body (the vagina), arguing against a genetic basis for this disorder. The term "crackleware" oesophagus was used to describe this entity, which has not been described previously in the English literature.

CagA-positive Helicobacter pylori infection is not associated with decreased risk of Barrett's esophagus in a population with high H. pylori infection rate

BACKGROUND & AIM

The role that H. pylori infection plays in the development of and Barrett's esophagus (BE) is uncertain. We tested the hypothesis that infection with cagA+ Helicobacter pylori strains protects against the development of BE.

METHODS

We studied 104 consecutive patients, residents in an area with a high prevalence of H. pylori infection, with BE and 213 sex- and age-matched controls. H. pylori infection and CagA antibody status were determined by western blot serology.

RESULTS

H. pylori prevalence was higher in patients with BE than in controls (87.5% vs. 74.6%; OR. 2.3; 95% CI: 1.23-4.59). Increasing age was associated with a higher prevalence of H. pylori (p < 0.05). The prevalence of CagA+ H. pylori serology was similar in patients with BE and controls (64.4% vs. 54.5%; NS). Type I H. pylori infection (CagA+ and VacA+) was similar in patients with BE and controls (44.2% vs. 41.3%; NS). Logistic regression analysis identified alcohol (O.R. 7.09; 95% CI 2.23-22.51), and H. pylori infection (OR: 2.41; 95%CI: 1.20-4.84) but not CagA+ serology as independent factors.

CONCLUSION

Neither H. pylori infection nor H. pylori infection by CagA+ strains reduce the risk of BE in a population with high prevalence of H. pylori infection.

Distinction between short-segment Barrett’s esophageal and cardiac intestinal metaplasia

AIM: To investigate the roles of mucin histochemistry, cytokeratin 7/20 (CK7/20) immunoreactivity, clinical characteristics and endoscopy to distinguish short-segment Barrett’s esophageal (SSBE) from cardiac intestinal metaplasia (CIM).

METHODS: High iron diamine/Alcian blue (HID/AB) mucin-histochemical staining and immunohistochemical staining were used to classify intestinal metaplasia (IM) and to determine CK7/20 immunoreactivity pattern in SSBE and CIM, respectively, and these results were compared with endoscopical diagnosis and the positive rate of gastroesophageal reflux disease (GERD) symptoms and H pylori infection. Long-segment Barrett’s esophageal and IM of gastric antrum were designed as control.

RESULTS: The prevalence of type III IM was significantly higher in SSBE than in CIM (63.33% vs 23.08%, P<0.005). The CK7/20 immunoreactivity in SSBE showed mainly Barrett’s pattern (76.66%), and the GERD symptoms in most cases which showed Barrett’s pattern were positive, whereas H pylori infection was negative. However, the CK7/20 immunoreactivity in CIM was gastric pattern preponderantly (61.54%), but there were 23.08% cases that showed Barrett’s pattern. H pylori infection in all cases which showed gastric pattern was significantly higher than those which showed Barrett’s pattern (63.83% vs 19.30%, P<0.005), whereas the GERD symptoms in gastric pattern were significantly lower than that in Barrett’s pattern (21.28% vs 85.96%, P<0.005).

CONCLUSION: Distinction of SSBE from CIM should not be based on a single method; however, the combination of clinical characteristics, histology, mucin histochemistry, CK7/20 immunoreactivity, and endoscopic biopsy should be applied. Type III IM, presence of GERD symptoms, and Barrett’s CK7/20 immunoreactivity pattern may support the diagnosis of SSBE, whereas non-type III IM, positive H pylori infection, and gastric CK7/20 immunoreactivity pattern may imply CIM.

A comparative analysis by SAGE of gene expression profiles of Barrett's esophagus, normal squamous esophagus, and gastric cardia

BACKGROUND & AIMS

The metaplastic process in which the normal squamous epithelium of the distal esophagus is replaced by columnar-lined epithelium, known as Barrett's esophagus (BE), is poorly understood. The aim of this study was to define, analyze, and compare transcription profiles of BE, normal cardia epithelium, and squamous epithelium to gain more insight into the process of metaplasia and to identify uniquely expressed genes in these epithelia.

METHODS

Serial analysis of gene expression was applied for obtaining transcription libraries of biopsy specimens taken from a BE-affected patient with intestinal type of metaplasia and from normal squamous and gastric cardia epithelia. Validation of results by reverse-transcription polymerase chain reaction and immunoblotting was performed using tissues of 20 patients with BE.

RESULTS

More than 120,000 tags were sequenced. Between BE and squamous 776, and between BE and gastric cardia 534 tags were significantly differentially expressed (P < .05, pairwise comparison). In contrast, squamous compared with gastric cardia epithelia showed significant differential expression of 1316 tags. The most up-regulated genes in BE compared with squamous epithelium were trefoil factors, annexin A10, and galectin-4. Each of the epithelia showed a unique cytokeratin expression profile.

CONCLUSIONS

This study provides a comparison of the transcriptomes of BE, squamous epithelium, and gastric cardia epithelium. BE proves to be an incompletely differentiated type of epithelium that shows similarities to both normal squamous and gastric cardia epithelia. In addition, several uniquely expressed genes are identified. These results are a major advancement in understanding the process of metaplasia that leads to BE.

Newly developed assay measuring cytokeratins 8, 18 and 19 in serum is correlated to survival and tumor volume in patients with esophageal carcinoma

Esophageal carcinoma is the seventh most common cause of cancer-related death in the Western world. In Sweden, approximately 400 new esophageal carcinomas are diagnosed yearly. Cytokeratins (CK) are specific for epithelial cells and the expression profile usually remains unchanged even when the epithelium undergoes malignant transformation. In the present study, MonoTotal, a newly developed RIA-assay detecting circulating CK 8, 18 and 19 fragments, was investigated in sera from patients with esophageal carcinoma. Serum samples from 40 patients with esophageal carcinoma were collected. The median value of circulating CK 8, 18 and 19 measured with MonoTotal was 378 U/L (range 53-6843) and with regard to the defined cut-off (< 75 U/L), 39/40 (98%) patients were shown to have elevated levels of circulating CK 8, 18 and 19. Patients with localized disease had a median value of circulating CK 8, 18 and 19 of 305 U/L (mean: 500 U/L), whereas the corresponding value for metastatic disease was 771 U/L (mean: 1506 U/L). This difference was statistically significant (P = 0.016). Circulating CK 8, 18 and 19, according to cut-off, were not associated with survival in univariate analysis (P = 0.34). However, continuous values of circulating levels of CK 8, 18 and 19 were associated with survival (P = 0.000083) in univariate as well as in the multivariate analysis (P = 0.03). In conclusion, circulating CK 8, 18 and 19 correlates with increased tumor burden and might, in conjunction with other clinical parameters, aid the clinician in estimating the prognosis of the individual patient.

Cytokeratin phenotyping does not help in distinguishing oesophageal adenocarcinoma from cancer of the gastric cardia

BACKGROUND

It is sometimes difficult to distinguish between cardia cancer and oesophageal cancer.

AIMS

To evaluate whether cytokeratin (CK) expression of the tumour can be of value in differentiating between the two tumour types.

METHODS

Consecutive patients with a malignant tumour in the oesophagus or stomach were recruited. Biopsy specimens were taken for routine haematoxylin and eosin staining. One tissue block with representative tissue was selected for immunohistochemical staining (CK7 and CK20).

RESULTS

Endoscopically located adenocarcinoma of the oesophagus was present in 84 patients (64 men, 20 women; mean age, 68 years; range, 44-91). Cancer located primarily in the gastric cardia was present in 63 patients (42 men, 21 women; mean age, 68 years; range, 42-88). The histological diagnosis was metastasis from a primary tumour outside the oesophagus or stomach in 19 patients. The patients were divided into three groups for the immunohistochemical analysis. Patients in group A had definite oesophageal cancer, group B patients had a definite carcinoma located in the gastric cardia, and group C patients had an obstructing tumour distal in the oesophagus at the level of the diaphragm, which could not be passed with the endoscope. Paraffin wax embedded material was available from 122 patients for immunostaining and CK analysis. There was no significant difference in expression or distribution of CK7 or CK20 in the three groups of patients.

CONCLUSION

CK phenotyping cannot distinguish between cancer arising from a Barrett's oesophagus and carcinoma originating in the gastric cardia.

Gastroesophageal reflux and cancer

The causal relationship between GERD and esophageal adenocarcinoma, although unclear just a few decades ago, now is established fairly well. The physiologic changes and the biocellular alterations of the damaged esophageal mucosa are documented better. Despite this knowledge, the dramatic increase in the incidence of esophageal cancer cannot be explained. The absolute risk of esophageal adenocarcinoma arising from GERD is low, and, at present, does not justify population-screening programs. Still, with the notion that adenocarcinoma of the esophagus is an aggressive cancer once documented, important questions still are in need of answers for patients suffering from reflux symptoms. Patients who have reflux disease are not necessarily symptomatic. It remains unclear if patients experiencing reflux symptoms should undergo mandatory endoscopy with biopsies at the esophagogastric junction. Furthermore, metaplasia of the lower esophagus often is not readily recognizable at endoscopy, and only biopsies can document abnormal histology. A severe and prolonged history of reflux always should orient to the possibility of a reflux-related columnar-lined esophagus. Once documented, Barrett's esophagus needs to be seen as a premalignant condition not necessarily leading to adenocarcinoma formation; despite their increased risk of tumor formation, most patients who have Barrett's esophagus die of other causes. During regular endoscopic follow-up, multilevel circumferential biopsies should document the evolution of the histologic changes in the lower esophagus and at the gastroesophageal junction of these patients. It is the only method available to document the appearance of dysplasia. It still is unclear if medicine or surgery provides the best quality of life and the best protection against the development of dysplasia and the possible progression toward adenocarcinoma formation when intestinal metaplasia is present in the esophagus.

Cytokeratin 7 and 20 expression in intestinal metaplasia of the distal oesophagus: relationship to gastro-oesophageal reflux disease

AIMS

Intestinal metaplasia and gastro-oesophageal reflux disease typify classical Barrett's oesophagus. Cytokeratin (CK) 7 and 20 phenotypes differentiate intestinal metaplasia in long segment Barrett's oesophagus from gastric intestinal metaplasia. This study examines the relationship between CK7/20 phenotypes and reflux disease in intestinal metaplasia of the distal oesophagus.

METHODS AND RESULTS

Eighty patients with oesophageal pH studies included 30 with long segment Barrett's, 16 with short segment Barrett's and 34 with intestinal meatplasia of the gastro-oesophageal junction. Representative biopsy specimens were immunostained for CK7 and CK20. All 30 long segment patients demonstrated a Barrett's CK7/20 phenotype. All nine short segment patients with gastro-oesophageal reflux had a Barrett's CK7/20 phenotype, while four of seven short segment patients without reflux had a gastric CK7/20 phenotype (P = 0.019). Of 14 patients with intestinal metaplasia of the gastro-oesophageal junction and reflux, 10 (71%) had a Barrett's CK7/20 phenotype, compared with 11 (55%) of the 20 non-reflux patients.

CONCLUSIONS

CK7/20 immunoreactivity for patients with intestinal metaplasia of the distal oesophagus without long segment Barrett's oesophagus suggests a heterogeneous group, with an association between Barrett's CK7/20 pattern and gastro-oesophageal reflux disease in both short segment Barrett's and intestinal metaplasia of the gastro-oesophageal junction.

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.

Unraveling the mystery of the gastroesophageal junction: a pathologist's perspective

The gastroesophageal junction (GEJ), which is defined as the point where the distal esophagus joins the proximal stomach (cardia), is a short anatomic area that is commonly exposed to the injurious effects of GERD and/or Helicobacter pylori infection. These disorders often lead to inflammation and intestinal metaplasia (IM) of this anatomic region. The true gastric cardia is an extremely short segment (<0.4 mm) of mucosa that is typically composed of pure mucous glands, or mixed mucous/oxyntic glands that are histologically indistinguishable from metaplastic mucinous columnar epithelium of the distal esophagus. In patients with GERD, whether physiologic or pathologic, the length of cardia-type epithelium increases and extends proximally above the level of the anatomic GEJ into the distal esophagus. Columnar metaplasia of the distal esophagus represents a squamous to columnar metaplastic reaction that develops from an esophageal stem cell and may pass through an intermediate phase characterized by the presence of a type of epithelium that possesses a mixture of squamous and columnar features, termed multilayered epithelium. In contrast, IM of the gastric cardia represents a columnar to columnar cell metaplastic reaction that develops from a gastric stem cell located in the deep foveolar compartment of the gastric mucosa. Intestinal metaplasia, particularly the incomplete type, is widely believed to represent the precursor lesion upon which dysplasia and cancer arises. The frequency of IM is probably greater in metaplastic columnar epithelium in the esophagus secondary to GERD, than in cases of true gastric carditis secondary to H. pylori, and may be a reason why there is a higher risk of carcinoma in the former compared to the latter. A variety of clinical, endoscopic, histologic, and histochemical methods can be used to distinguish GERD-induced columnar metaplasia of the distal esophagus from H. pylori-induced inflammation of true gastric cardia, and these are outlined in this review, but further controlled studies are needed to critically evaluate these techniques. Further prospective trials are needed to adequately evaluate the different etiologic and pathogenetic mechanisms and, most importantly, the risk of malignancy in these two conditions.

Controversies of the cardiac mucosa and Barrett's oesophagus

Confusion regarding the diagnosis of Barrett's oesophagus exists because of a false dogma that cardiac mucosa is normally present in the gastro-oesophageal junctional region. Recent data indicate that the only normal epithelia in the oesophagus and proximal stomach are squamous epithelium and gastric oxyntic mucosa. When this fact is recognized, it becomes easy to develop precise histological definitions for the normal state (presence of only squamous and oxyntic mucosa), metaplastic oesophageal columnar epithelium (cardiac mucosa with and without intestinal metaplasia, and oxynto-cardiac mucosa), the gastro-oesophageal junction (the proximal limit of gastric oxyntic mucosa), the oesophagus (that part of the foregut lined by squamous and metaplastic columnar epithelium), reflux disease (the presence of metaplastic columnar epithelium), and Barrett's oesophagus (cardiac mucosa with intestinal metaplasia). It is also possible to assess accurately the severity of reflux which is directly proportional to the amount of metaplastic columnar epithelium, and the risk of adenocarcinoma which is related to the amount of dysplasia in intestinal metaplastic epithelium present within the columnar lined segment of the oesophagus. Histopathological precision cannot be matched by any other modality and can convert the confusion that exists regarding diagnosis of Barrett's oesophagus to complete lucidity in a manner that is simple, accurate, and reproducible.

Is cytokeratin immunoreactivity useful in the diagnosis of short-segment Barrett's oesophagus in Korea?

BACKGROUND

Cytokeratin 7/20 staining has been reported to be helpful in diagnosing Barrett's oesophagus and gastric intestinal metaplasia. However, this is still a matter of some controversy.

OBJECTIVE

To determine the diagnostic usefulness of cytokeratin 7/20 immunostaining for short-segment Barrett's oesophagus in Korea.

METHODS

In patients with Barrett's oesophagus, diagnosed endoscopically, at least two biopsy specimens were taken from just below the squamocolumnar junction. If goblet cells were found histologically with alcian blue staining, cytokeratin 7/20 immunohistochemical stains were performed. Intestinal metaplasia at the cardia was diagnosed whenever biopsy specimens taken from within 2 cm below the oesophagogastric junction revealed intestinal metaplasia. Barrett's cytokeratin 7/20 pattern was defined as cytokeratin 20 positivity in only the superficial gland, combined with cytokeratin 7 positivity in both the superficial and deep glands.

RESULTS

Barrett's cytokeratin 7/20 pattern was observed in 28 out of 36 cases (77.8%) with short-segment Barrett's oesophagus, 11 out of 28 cases (39.3%) with intestinal metaplasia at the cardia, and nine out of 61 cases (14.8%) with gastric intestinal metaplasia. The sensitivity and specificity of Barrett's cytokeratin 7/20 pattern were 77.8 and 77.5%, respectively.

CONCLUSION

Barrett's cytokeratin 7/20 pattern can be a useful marker for the diagnosis of short-segment Barrett's oesophagus, although the false positive or false negative rate is approximately 25%.

Cytokeratin immunoreactivity patterns in short-segment Barrett's esophagus in Japanese patients

BACKGROUND

The origin of intestinal metaplasia at the esophagogastric junction has clinical importance. However, it can be difficult to differentiate between intestinal metaplasia of short-segment Barrett's esophagus and cardiac intestinal metaplasia due to Helicobacter pylori infection. Specific patterns of cytokeratin (CK)7 and CK20 have been detected in long-segment Barrett's esophagus. The aim of the present study was to assess the immunostaining patterns associated with short-segment Barrett's esophagus.

AIMS

Paraffin-embedded biopsy specimens were prepared from 128 patients with intestinal metaplasia of long-segment Barrett's esophagus (n = 3), short-segment Barrett's esophagus without H. pylori infection (n = 22), short-segment Barrett's esophagus with H. pylori infection (n = 22), and cardiac mucosa (n = 49) and gastric mucosa from antrum and fundus (n = 44) with H. pylori infection. Sections were prepared and immunostained for CK7 and CK20.

RESULT

A Barrett's CK7/20 pattern was present in all three patients (100%) with long-segment Barrett's esophagus, 21 of 22 patients (95%) with short-segment Barrett's esophagus without H. pylori infection, and six of 22 patients (27%) with short-segment Barrett's esophagus with H. pylori infection (P < 0.05).

CONCLUSION

Intestinal metaplasia of short-segment Barrett's esophagus in patients without H. pylori infection is thought to be similar to that seen in long-segment Barrett's esophagus.

Cytokeratins 7 and 20 and mucin core protein expression in esophageal cervical inlet patch

Cervical inlet patch (CIP) is defined by the presence of gastric mucosa within the first few centimeters of the esophagus. Several endoscopic series have demonstrated a frequent association of CIP with Barrett's esophagus (BE) suggesting a pathogenetic link. A histochemical study reporting the presence of acid mucin in CIP, including sulfomucin, supports this hypothesis. We evaluated mucin core protein expression and cytokeratins 7 and 20 (CK7/CK20) pattern in biopsies of CIP, normal antrum, and BE to comment on a possible relationship of CIP with BE. We observed that both lesions have similar cytokeratin patterns with mixed CK7/CK20 reactivity on the surface and pits and lone CK7 positivity in the glands. MUC5AC was strongly expressed on the surface and pits but not in the glands of CIP and antral mucosa. Within BE, MUC5AC positivity was noted not only on the surface and pits but also in the glands. MUC6 similarly decorated the glands of CIP and BE. MUC2 was expressed rarely in CIP with goblet cells but conspicuously on the surface and pits of BE. MUC5B was seen in both CIP and BE and rarely in the antral mucosa. The similarities between CIP and BE but not with normal antral mucosa fits with the hypothesis that both lesions may originate from submucosal esophageal mucous glands. Two pathogenetic pathways can be entertained: focal upper esophageal mucosal misdevelopment in pediatric population and patchy metaplastic replacement of squamous mucosa in adults with gastroesophageal reflux disease.

Inflammation and cytokeratin 7/20 staining of cardiac mucosa in young patients with and without Helicobacter pylori infection

BACKGROUND

Both Helicobacter pylori and gastro-oesophageal reflux disease (GORD) may cause inflammation in cardiac mucosa. Intestinal metaplasia (IM) is found more often in GORD associated inflammation than in inflammation caused by H pylori, especially in young individuals.

AIM

To examine morphological differences in chronic inflammation in these two conditions by immunohistochemistry.

PATIENTS/METHODS

Tissue blocks from cardiac mucosa of patients <45 years were available as follows: 10 patients with chronic inflammation of cardiac mucosa (carditis) and H pylori gastritis (group 1); 10 patients with (possibly GORD related) carditis, but normal antrum and corpus (group 2); and 10 patients with non-inflamed cardiac mucosa and normal antrum and corpus (group 3). Haematoxylin and eosin staining and immunohistochemical staining for various inflammatory cells were performed for patients in groups 1 and 2 as follows: CD20 (B cells), CD3 (T cells), CD4 (T helper cells), CD8 (T suppressor cells), CD163 (macrophages), CD138 (plasma cells), and CD117 (mast cells). For all patients, cytokeratin 7/20 (CK7/20) staining was performed.

RESULTS

No clear differences were seen in the morphology of chronic inflammation between groups 1 and 2. In both, plasma cells were most abundant. CK7/20 staining showed no differences between these groups.

CONCLUSION

Helicobacter pylori negative (possibly GORD associated) and H pylori related carditis cannot be distinguished on a morphological basis. The stronger tendency towards IM in the first entity cannot be explained by differences in the type of inflammation. Barrett-type CK7/20 staining seems typical for cardiac mucosa, irrespective of the type of inflammation or presence of IM.

Epidemiology, pathophysiology, and treatment of Barrett's esophagus: reducing mortality from esophageal adenocarcinoma

The definition of BE has evolved over time. BE is the key premalignant lesion for developing EAC. The epidemiology and pathophysiology of BE is outlined, and risk factors for BE and EAC are reviewed. GERD plays a crucial role in the pathophysiology and the clinical identification of BE. Endoscopy with biopsy is the best tool for diagnosing and surveying patients with BE. Detection of early neoplasia is the present approach to reduce EAC mortality. Novel technology should assist in the early detection of dysplasia to enable targeted therapy. Effective chemopreventive strategies may reduce the risk of progression to EAC.

Does Cytokeratin7/20 immunoreactivity help to distinguish Barrett's esophagus from gastric intestinal metaplasia? Results of a prospective study of 75 patients

Barrett's esophagus is a recognized risk factor for the development of esophageal dysplasia and carcinoma. Unfortunately, gastric incomplete intestinal metaplasia arising in Short Segment Barrett's esophagus can be indistinguishable histologically on hematoxylin/eosin stains. Distinct patterns of CK 7 and CK 20 immunohistochemical expression have been demonstrated to be both highly sensitive and specific for Barrett's esophagus, but have not been found in gastric metaplasia. The aim of our study was to test whether immunostaining with CK 7/20 helps to distinguish between Barrett's epithelium and gastric incomplete metaplasia. Cases of long segment Barrett's esophagus, short segment Barrett's esophagus, and cases with a normal gastroesophageal junction, as well as specimens with gastric antral intestninal metaplasia, were examined: three patterns were defined. Barrett's pattern (superficial CK 20 staining; superficial and crypt CK 7 staining); gastric pattern (superficial and crypt staining of both markers); other patterns (different from Barrett and gastric types). Seventy-five patients were enrolled in this study, 26 with long segment Barrett's esophagus, 21 with short segment esophagus, 13 with intestinal metaplasia of the cardia, and 18 with antral intestinal metaplasia. The Barrett pattern showed a high specificity of 97%, but a sensitivity of only 30% in patients with short segment Barrett esophagus. Our results do not confirm the hypothesis that CK 7/20 immunostaining can be used for a reliable differentiation between incomplete intestinal metaplasia and Barrett's epithelium.

What is the role of cytokeratins in Barrett/cardia differentiation?

The importance of distinguishing between Barrett metaplasia and intestinal metaplasia of the gastric cardia is now accepted, and the management of each entity is quite different. Patients with Barrett metaplasia are enrolled in surveillance programs, consisting of periodic endoscopy and biopsy, because of the known risk of developing adenocarcinoma of the esophagus. Patients with intestinal metaplasia of the gastric cardia, however, are not currently enrolled in such programs, because this condition carries a low risk of developing adenocarcinoma of the gastric cardia. The distinction between both conditions by morphologic examination of routine histologic sections of endoscopic biopsies is extremely difficult if at all possible. A group of investigators proposed the use of immunostains for cytokeratin (CK) 7 and CK20 to overcome such difficulty. They concluded that the Barrett CK7/CK20 pattern was a highly sensitive and specific marker for Barrett metaplasia. Their observations, however, were not confirmed by other investigators. However, because it may be associated with premalignant lesions elsewhere in the gastric mucosa, we propose that intestinal metaplasia of the gastric cardia may have the same clinical implication as Barrett metaplasia.

Interinstitutional variability and effect of tissue fixative on the interpretation of a Barrett cytokeratin 7/20 immunoreactivity pattern in Barrett esophagus

A unique pattern of cytokeratin (CK) 7/20 immunostaining (diffuse staining with CK7 and surface and superficial crypt staining with CK20) has been reported to be useful in differentiating Barrett esophagus (BE) from intestinal metaplasia of the stomach. However, there are conflicting results regarding the prevalence of a BE CK7/20 staining pattern in BE between different studies. Therefore, this study was performed to determine the degree of variability in interpretation of a BE CK7/20 pattern and to determine the reasons for variability when present. Esophageal and gastric mucosal biopsies from 67 patients with BE and antral intestinal metaplasia at 2 institutions were immunostained for CK7/20. All cases were evaluated for the presence of a BE CK7/20 pattern by 2 gastrointestinal pathologists from each institution, and the degree of agreement between institutions was determined. To determine the effect of tissue fixation and staining methods on the pattern of CK7/20 staining, unstained slides were exchanged between institutions, stained separately by each institution, and reexamined by all pathologists. There was excellent agreement on the presence of a BE CK7/20 staining pattern between pathologists at the same institution but only moderate agreement between pathologists at different institutions (71% overall, kappa = 0.58). Among BE cases, a BE CK7/20 staining pattern was identified in 50 (96%) of 52 cases by Cleveland Clinic Foundation pathologists but only 35 (67%) of 52 cases by Brigham and Women's Hospital pathologists. The major source of disagreement related to the interpretation of weak or variable CK7 staining of deep intestinalized mucosa in BE biopsies that were fixed in Hollande, but not those that were fixed in formalin. After the creation of a new set of criteria for a positive BE CK7/20 staining pattern, which took into account the effects of Hollande's fixative, the degree of agreement between pathologists at each of the 2 institutions was excellent (100%, kappa value = 1.0). Therefore, the CK7/20 staining pattern is influenced by the type of fixative used. Only a moderate level of interobserver agreement among pathologists regarding a BE CK7/20 pattern can be achieved if one is not aware of these effects. Nevertheless, specific criteria for interpretation of CK7/20 staining can be successfully applied between institutions and need to be developed before use of this technique in clinical practice.

Crystal violet chromoendoscopy with mucosal pit pattern diagnosis is useful for surveillance of short-segment Barrett's esophagus

BACKGROUND

Because of a rapid increase in the incidence of Barrett's cancer, the appropriate surveillance method for Barrett's esophagus is of interest. Methylene blue chromoendoscopy has been reported to be an effective and inexpensive method to improve biopsy surveillance of Barrett's epithelium. However, the usefulness of this method in short-segment Barrett's esophagus cases is still controversial.

AIMS

This study was undertaken to evaluate the abilities of crystal violet and methylene blue chromoendoscopy to detect potentially dysplastic Barrett's epithelium in cases with short-segment columnar-appearing epithelium of the esophago-gastric junction.

PATIENTS AND METHODS

Four hundred patients with endoscopically suspected short-segment Barrett's esophagus were enrolled and randomly assigned to receive chromoendoscopy with 0.05% crystal violet, 0.1% crystal violet, 0.5% methylene blue, or 1.0% methylene blue. During crystal violet and methylene blue chromoendoscopy, biopsy specimens were obtained from stained and unstained columnar-appearing epithelium of the esophago-gastric junction, and the detection rates of Barrett's epithelium were evaluated. The value of pit pattern diagnosis was also evaluated as a possible way to detect dysplastic Barrett's epithelium.

RESULTS

Chromoendoscopy with 0.05% crystal violet detected histologically confirmed Barrett's epithelium with the highest sensitivity (89.2%) and specificity (85.7%). Crystal violet clearly stained both dysplastic and nondysplastic Barrett's epithelia and made the surface pit pattern easy to observe without using magnifying endoscopy.

CONCLUSIONS

The combination of crystal violet chromoendoscopy and pit pattern diagnosis is considered to be useful for the surveillance of short-segment Barrett's esophagus.

Immunohistochemical analysis of short-segment Barrett's esophagus

BACKGROUND AND AIMS

The majority of dysplasias and adenocarcinomas in Barrett's esophagus are closely associated with the specialized columnar epithelium. In this study, we performed an immunohistochemical analysis of columnar metaplasia presenting in short-segment Barrett's esophagus (SSBE).

PATIENTS AND METHODS

The endoscopic biopsy specimens obtained from 91 patients were analyzed. Ten were cases of long-segment Barrett's esophagus (LSBE) and 81 had SSBE. Expression of MUC2, MUC5AC, Con A and CD10 was evaluated using immunohistochemical staining.

RESULTS

All samples from LSBE (n = 9) were histologically diagnosed as specialized columnar epithelium. The 81 SSBE samples were divided into gastric fundic-type (n = 26), junctional-type (n = 16) and specialized columnar epithelium (n = 39). In the specialized columnar epithelium of SSBE, there was a predominance of goblet cell-type metaplasia proposed by Watanabe et al. which is characterized by MUC2-positive pyloric epithelium (66.7%). The total percentage of non-goblet cell-type and goblet cell-type was 76.9%. In contrast, 80% of LSBE revealed the large intestinal-type or the large and small intestinal-type. The long oval and villous pit by magnifying endoscope suggests the presence of the specialized columnar epithelium, but the phenotypic classification of Watanabe's criteria was not associated with the endoscopic pit pattern.

CONCLUSION

Intestinal metaplasia in Barrett's esophagus changes immunohistochemically with progress of the disease.

Cytokeratin 7/20 and MUC1, 2, 5AC, and 6 expression patterns in Barrett's esophagus and intestinal metaplasia of the stomach: intestinal metaplasia of the cardia is related to Barrett's esophagus

Intestinal metaplasia (IM) in endoscopic biopsies obtained from close to the gastroesophageal junction may represent IM of the cardia (CIM) or Barrett's esophagus (BE), which have different malignant potentials despite similar morphology. This study compared cytokeratin (CK) 7/20 and mucin (MUC1, 2, 5AC, and 6) immunopatterns in biopsies from BE (n = 41), CIM (n = 35), and antral gastric IM (AIM, n = 37) to evaluate their roles as diagnostic aids. CK7 and CK20 expression was described as absent, patchy (superficial and deep), continuous superficial only, continuous deep only, and diffuse. Eleven different combinations of CK7/20 expression were seen. Since CK20 staining was positive in all cases, four main patterns were defined on the basis of the observed CK7 staining as 1, absent; 2, patchy (superficial and/or deep); 3, diffuse; and 4, continuous superficial only. Overall CK7 positivity (regardless of pattern) was higher in BE and CIM than in AIM. CK patterns 3 and 4 were also higher in BE and CIM than in AIM. For either pattern 3 or 4, the positive and negative predictive values for BE versus AIM were 95% and 67%, respectively. MUC1 was rarely expressed in BE and CIM compared with AIM, whereas the opposite was noted for MUC5AC expression. MUC2 and MUC6 expression was similar in all locations. In conclusion, diffuse or continuous superficial CK7 staining is highly characteristic of BE and CIM and contrasts with AIM. It is, however, not very sensitive. CK20 profiles have no added value. Mucin expression also differs between BE and CIM versus AIM, but the specificity of any pattern is insufficient for distinction in individual cases. Importantly, CK and MUC expression patterns in BE and CIM are virtually indistinguishable, limiting their use in this differential and raising the question of whether they are biologically related.

Cardiac mucosa in the remnant esophagus after esophagectomy is an acquired epithelium with Barrett's-like features

BACKGROUND

The cervical esophagus is normally lined by squamous epithelium and is usually not exposed to gastroesophageal reflux. The aims of this study were, first, to investigate whether cardiac mucosa can be acquired in the remnant cervical esophagus after esophagectomy and cervical esophagogastrostomy and, second, to characterize this mucosa if present.

METHODS

The medical records of 100 patients who had undergone esophagectomy with gastric pull-up reconstruction were studied retrospectively to identify those who had biopsies from the cervical esophagus proximal to the gastroesophageal anastomosis during postoperative follow-up. The histopathology and immunohistochemical stains were reviewed to assess similarity to Barrett's mucosa (cytokeratins [CK] 7 and 20 and DAS-1), cellular proliferation (topoisomerase 2alpha), and the potential for dysplasia (cyclo-oxygenase 2 [COX-2] and ornithine decarboxylase [ODC]).

RESULTS

Supra-anastomotic biopsies were performed in 20 patients. Cardiac mucosa was present in 10 of 20 (50%) patients in whom biopsies were performed. Four patients had areas of intestinal metaplasia, and dysplasia, and adenocarcinoma developed in 1 patient. The CK7/20 and DAS-1 staining of the columnar mucosa showed a pattern similar to Barrett's mucosa. Topoisomerase 2alpha protein expression was present in 50% of patients with cardiac mucosa. DAS-1 protein was expressed in cervical columnar mucosa but not in normal squamous esophagus mucosa. The cardiac mucosa stained weakly for COX-2 and ODC.

CONCLUSIONS

Cardiac mucosa can be acquired. Its expression profile is similar to cardiac mucosa and intestinal metaplasia found in Barrett's esophagus, and different from normal esophageal or gastric mucosa. The development of cardiac mucosa is likely to be related to reflux of acid into the remnant cervical esophagus as the first step in the development of Barrett's esophagus. These findings are applicable to the development of similar changes at the gastroesophageal junction.

A critical review of the diagnosis and management of Barrett's esophagus: the AGA Chicago Workshop

BACKGROUND & AIMS

The diagnosis and management of Barrett's esophagus (BE) are controversial. We conducted a critical review of the literature in BE to provide guidance on clinically relevant issues.

METHODS

A multidisciplinary group of 18 participants evaluated the strength and the grade of evidence for 42 statements pertaining to the diagnosis, screening, surveillance, and treatment of BE. Each member anonymously voted to accept or reject statements based on the strength of evidence and his own expert opinion.

RESULTS

There was strong consensus on most statements for acceptance or rejection. Members rejected statements that screening for BE has been shown to improve mortality from adenocarcinoma or to be cost-effective. Contrary to published clinical guidelines, they did not feel that screening should be recommended for adults over age 50, regardless of age or duration of heartburn. Members were divided on whether surveillance prolongs survival, although the majority agreed that it detects curable neoplasia and can be cost-effective in selected patients. The majority did not feel that acid-reduction therapy reduces the risk of esophageal adenocarcinoma but did agree that nonsteroidal antiinflammatory drugs are associated with a cancer risk reduction and are of promising (but unproven) value. Participants rejected the notion that mucosal ablation with acid suppression prevents adenocarcinoma in BE but agreed that this may be an appropriate strategy in a subgroup of patients with high-grade dysplasia.

CONCLUSIONS

Based on this review of BE, the opinions of workshop members on issues pertaining to screening and surveillance are at variance with published clinical guidelines.

Distinction between intestinal metaplasia in the cardia and in Barrett's esophagus: the role of histology and immunohistochemistry

Intestinal metaplasia in Barrett's esophagus (BIM) is a precancerous condition, whereas the carcinogenic potential of intestinal metaplasia of the cardia (CIM) is uncertain. Although clinically important, histological distinction between both conditions by endoscopic biopsies is considered problematic. In the present study, 4-mm samples of BIM (n=31) and CIM (n=9) were selected from esophagectomy specimens that had been resected for esophageal cancer. Slides were coded and stained with hematoxylin and eosin (H&E), Alcian blue-periodic acid-Schiff (PAS), cytokeratins (CK) 7 and 20, and CD10, which labels the intestinal brush border. The predictive value of these stains for the recognition of BIM and CIM was evaluated independently by two senior pathologists. With the use of H&E-stained slides exclusively, BIM samples were categorized correctly in 93.5% and 83.9% of cases (pathologists 1 and 2, respectively), and CIM samples, in 100% and 88.9% of cases. Alcian blue-PAS-positive goblet cells were identified by both investigators in all BIM and CIM samples. BIM-typical CK 7 and 20 immunostaining pattern was identified in 90.3%/83.9% of BIM but only in 11.1%/11.1% of CIM. CD10-positive brush border was present in 32.3%/25.8% of BIM and in 88.9%/88.9% of CIM. When HE-stained slides and immunohistologically stained slides were used together for tissue recognition, BIM were categorized correctly in 90.3%/80.6% of cases, and CIM, in 88.9%/88.9% of cases. In conclusion, BIM and CIM can be usually distinguished on the basis of HE sections. CK 7 and CK 20 expression pattern analysis discriminates correctly between BIM and CIM in the majority of cases. CD10-positive intestinal brush border is present in the majority of CIM but only in a minority of BIM. However, immunohistochemical investigations could not improve the diagnostic accuracy of HE histology alone.

Molecular classifiers for gastric cancer and nonmalignant diseases of the gastric mucosa

High incidence of gastric cancer-related death is mainly due to diagnosis at an advanced stage in addition to the lack of adequate neoadjuvant therapy. Hence, new tools aimed at early diagnosis would have a positive impact in the outcome of the disease. Using cDNA arrays having 376 genes either identified previously as altered in gastric tumors or known to be altered in human cancer, we determined expression signature of 99 tissue fragments representing normal gastric mucosa, gastritis, intestinal metaplasia, and adenocarcinomas. We first validated the array by identifying molecular markers that are associated with intestinal metaplasia, considered as a transition stage of gastric adenocarcinomas of the intestinal type as well as markers that are associated with diffuse type of gastric adenocarcinomas. Next, we applied Fisher's linear discriminant analysis in an exhaustive search of trios of genes that could be used to build classifiers for class distinction. Many classifiers could distinguish between normal and tumor samples, whereas, for the distinction of gastritis from tumor and for metaplasia from tumor, fewer classifiers were identified. Statistical validations showed that trios that discriminate between normal and tumor samples are powerful classifiers to distinguish between tumor and nontumor samples. More relevant, it was possible to identify samples of intestinal metaplasia that have expression signature resembling that of an adenocarcinoma and can now be used for follow-up of patients to determine their potential as a prognostic test for malignant transformation.

Heterotopic gastric mucosa of the esophagus: literature-review and proposal of a clinicopathologic classification

The prevalence of heterotopic gastric mucosa (HGM) in the cervical esophagus is frequently underestimated. Tiny microscopic foci have to be distinguished from a macroscopically visible patch, also called "inlet patch." Symptoms as well as morphologic changes associated with HGM are regarded as a result of the damaging effect of acid, produced by parietal cells in the mostly fundic type of HGM. We herein review the literature and propose a new clinicopathologic classification of esophageal HGM: Most of the carriers of esophageal HGM are asymptomatic (HGM I). Some individuals with HGM in the esophagus complain of dysphagia, odynophagia, or "extraesophageal manifestations" (hoarseness and coughing), without further morphologic findings (HGM II). Still fewer patients are symptomatic due to morphologic changes, i.e., esophageal strictures, webs, or esophagotracheal fistula (HGM III). Malignant transformation via dysplasia (intraepithelial neoplasia, HGM IV) to cervical esophageal adenocarcinoma (HGM V) is exceedingly rare (only 24 reported cases). In contrast to Barrett's esophagus, HGM should not be regarded as a precancerous lesion. Symptoms are more likely to occur in patients with inlet patch, whereas malignant transformation and adenocarcinogenesis can also occur in microscopic HGM foci. Asymptomatic HGM requires neither specific therapy nor endoscopic surveillance. Only in symptomatic cases treatment, i.e., dilatation for (benign) strictures or acid suppression for reflux symptoms, can be recommended. Patients with low-grade dysplasia in HGM might be candidates for surveillance strategies, whereas in cases of high-grade dysplasia and invasive adenocarcinoma oncological treatment strategies must be employed.

Expression of cytokeratins 7 and 20 in Helicobacter pylori-associated chronic gastritis in children

Helicobacter pylori gastric infection induces structural changes in the gastric epithelium. Among them, variations in the expression of cytokeratins have been reported in adult patients. In the present study, we describe the expression of CK7 and CK20 in gastric samples taken from the antrum in three groups of pediatric patients: (A) Helicobacter pylori-associated chronic gastritis (mean age: 11.4 years); (B) previous H. pylori chronic gastritis patients (mean age: 9.4 years); and (C) controls (mean age: 8.8 years). In all, the presence of sulfomucins was assessed with Alcian blue-periodic acid-Schiff pH 1.0. Immunoreactivity was graded as absent (0), weak (1+), moderate (2+), or intense (3+), in accordance with the intensity of the staining, and its distribution as focal or diffuse. CK7 reactivity was 2+ either focal or diffuse in all group A biopsies. The reactivity was more evident in the cells at the neck of the glands, in the areas with more inflammatory infiltrates, decorating long vertical segments of epithelium. In groups B and C, CK7 reactivity was also focal and 1+ at the cells of the necks of the glands. However, group B presented longer vertical segments of positive cells as compared to group C, and shorter than those of group A. The deeper glandular structures were focally 1+ in both groups. CK20 expression was comparable in all three groups, depicting a 2+ diffuse reactivity at the surface epithelium and interposed pits with absence or focal reactivity at the neck and coiled gland areas. Ki-67 immunostaining paralleled that of the CK7. Staining for sulfated mucosubstances was positive in two of five cases of groups A and B, and in none of the cases of group C. We conclude that: (1) the long segments of CK7-positive glandular necks in H. pylori cases most probably indicate intense regenerative activity during active inflammation; (2) eradication of H. pylori does not warrant ad integrum restitution since long segments of Ki-67+, CK7+ cells at the germinative compartment of the glands (as well as cells with sulfomucins) were still recognizable in ex- H. pylori patients; (3) finally, differing from what happens in adults, children somehow manage to maintain fully differentiated CK20+ superficial epithelium while the H. pylori is in action.

Barrett's esophagus: histopathologic definitions and diagnostic criteria

Adenocarcinoma of the distal esophagus is rising more rapidly in incidence than any other visceral malignancy in the Western world. It is well established that most, if not all, of these tumors develop in Barrett's esophagus via the metaplasia-dysplasia-carcinoma sequence and could theoretically be detected at an early stage, but despite this, the majority of these tumors are still detected late in their course. This highlights the fact that the goal of effective surveillance for patients at risk for developing an adenocarcinoma of the distal esophagus is still far off. In addition, adenocarcinomas of the esophagogastric junction and gastric cardia are also rising in incidence, but their carcinogenesis and their relation to Barrett's esophagus are still being defined, as are the meaning and significance of the relatively new entities "short-segment Barrett's" and "ultra-short-segment Barrett's". This review attempts to clarify the main histopathologic issues concerned with the definition of Barrett's esophagus, its distinction from intestinal metaplasia of the gastric cardia, as well as the criteria for the histologic diagnosis of dysplasia and carcinoma in Barrett's esophagus.

Identical cytokeratin expression pattern CK7+/CK20- in esophageal and cardiac cancer: etiopathological and clinical implications

Surgical treatment and prognosis is different in esophageal, cardiac and distal gastric adenocarcinomas. Determination of the origin, in particular of adenocarcinomas situated at the gastroesophageal junction, may be difficult. It has been suggested that esophageal adenocarcinomas are characterized by a specific cytokeratin pattern, namely the CK7+/CK20- pattern. According to the same authors, this cytokeratin pattern is absent in gastric adenocarcinomas. The aim of our study is to evaluate if this cytokeratin pattern CK7+/CK20- is absent in cardiac and distal gastric adenocarcinomas. Therefore, we evaluated the combined immunohistochemical expression of CK7 and CK20 on paraffin-embedded material of 214 resection specimens for adenocarcinoma, comprising 66 esophageal, 73 cardiac and 75 distal gastric adenocarcinomas (UICC-classification). The adenocarcinomas were subtyped into intestinal- and diffuse-type according to the Lauren classification. The immunohistochemical staining was considered as positive if 50% or more of the tumor cells were stained. Statistical analysis has been performed applying the chi2-test. The tumors situated at the gastroesophageal junction, esophageal as well as cardiac adenocarcinomas, showed predominantly a CK7+/CK20- expression pattern (67 vs 68%), whereas this cytokeratin pattern is rather uncommon in distal gastric adenocarcinomas (31%, P<4 x 10(-5)). Independent of their localization, intestinal- as well as diffuse-type adenocarcinomas have a similar cytokeratin pattern. Our data show that the combined expression of CK7 and CK20 is different for the adenocarcinomas situated on both sides of the gastroesophageal junction compared to the distal gastric adenocarcinomas. However, in contrast to data in the literature, the combined expression of CK7 and CK20 has a low specificity in the distinction between esophageal and cardiac adenocarcinomas. This may suggest a similar origin (cell lineage) and thus may have an impact on therapeutic strategies.

The utility of cytokeratins 7 and 20 (CK7/20) immunohistochemistry in the distinction of short-segment Barrett esophagus from gastric intestinal metaplasia: Is it reliable?

Background

The purpose of the present correlative immunohistochemical study was to assess the utility of cytokeratin (CK7 and CK20) expression in the diagnosis of short-segment Barrett esophagus, particularly its efficacy in differentiating Barrett mucosa from intestinal metaplasia of the gastric cardia and corpus.

Methods

Two groups of endoscopic biopsy specimens were examined, including 20 endoscopic biopsy specimens of short-segment Barrett esophagus (Group A) and equal number exhibiting Helicobacter pylori associated intestinal metaplasia of the gastric cardia and corpus (Group B). All were investigated by immunohistochemistry using the standard ABC method for CK7 and CK20 expression. Fisher's exact test was used for statistical analysis of Barrett CK7/20 and gastric CK7/20 patterns between the groups.

Results

The anticipated pattern of reactivity in Barrett mucosa (CK7: strong diffuse positivity in superficial and deep glands; CK20: positivity in surface epithelium and superficial glands) was seen in 2 cases of Group A specimens. The expected gastric pattern (CK7: patchy immunostaining with variable involvement of deep glands; CK20: patchy immunostaining of superficial and deep glands in incomplete intestinal metaplasia / absence of CK7 immunoreactivity with strong CK20 staining in superficial and deep glands in complete intestinal metaplasia) was seen in 8 cases of Group B specimens. The respective sensitivity and false-negativity values of CK7/20 staining for Barrett pattern in Group A were 10% and 90%, respectively. These values for gastric pattern in Group B were 40% and 60%, respectively. The specificity and false-positivity values of both patterns were same (100% and 0%, respectively). There was no statistically significant difference for Barrett pattern between the two groups (P = 0.487), while the observation of gastric pattern was significantly higher in Group B than in Group A (P = 0.02).

Conclusions

We concluded that these hypothesized and recently applied diagnostic criteria involving CK7 and CK20 immunoreactivity are not reliable in distinguishing short-segment Barrett esophagus from intestinal metaplasia as seen in gastric cardia and corpus.

Cdx2 as a marker of epithelial intestinal differentiation in the esophagus

The histologic diagnosis of Barrett's esophagus requires the presence of goblet cells, but this finding may not be the earliest indicator of intestinal metaplasia. We used immunohistochemistry to detect Cdx2, a transcriptional regulator important in the early differentiation and maintenance of intestinal epithelium, in 134 esophageal biopsy or resection specimens, including 62 with junctional-type epithelium (13 of which had equivocal histologic features of Barrett's epithelium), 34 with Barrett's epithelium without dysplasia, and 38 with Barrett's epithelium and dysplasia or carcinoma (13 low-grade dysplasias, 19 high-grade dysplasias, and 6 adenocarcinomas). We also performed PAS-alcian blue staining (pH 2.5) on adjacent sections. Cdx2 was observed in all cases of Barrett's epithelium. In some dysplasias (chiefly high-grade) and adenocarcinomas, there was diminution or focal loss of detectable protein. Cdx2 was detected in 20 of 62 cases (30%) of junctional-type epithelium, including 10 of 13 (77%) with equivocal histologic features of Barrett's epithelium. Acid mucin was present in goblet cells and non-goblet columnar cells in all cases of Barrett's esophagus and in non-goblet columnar cells in 48 of 62 cases (77%) with junctional-type epithelium only, including 17 of 20 (85%) that were Cdx2 positive and 31 of 42 (74%) that were Cdx2 negative. These results provide evidence that Cdx2 protein is a sensitive marker of intestinal metaplasia in the upper gastrointestinal tract and may be useful in detecting histologically equivocal cases of Barrett's esophagus. Cdx2 is present in dysplasia and adenocarcinoma, with some loss of protein primarily in high-grade dysplasia and adenocarcinoma. Acid mucin in non-goblet columnar cells is a common feature of Barrett's and junctional-type epithelium and may not always be indicative of intestinal metaplasia.

Mucin core peptide expression can help differentiate Barrett's esophagus from intestinal metaplasia of the stomach

It is important to distinguish Barrett's esophagus (BE) from intestinal metaplasia related to carditis because these conditions have a different natural history, risk of malignancy, and treatment. However, the distinction between these entities is difficult both clinically and pathologically. The aim of this study was to evaluate and compare the immunostaining pattern of five mucin core polypeptides in BE to cases of carditis or antritis with intestinal metaplasia. Routinely processed mucosal biopsies from 22 patients with intestinal-type BE, 24 patients with cardia intestinal metaplasia (10 Helicobacter pylori positive), 17 patients with antral intestinal metaplasia (all H. pylori positive), 20 control patients with a normal antrum, and 22 control patients with a normal cardia were immunostained with monoclonal antibodies against MUC1, MUC2, MUC3, MUC5AC, and MUC6 mucin core polypeptides. Staining was evaluated separately for goblet cells and non-goblet columnar cells and compared between all groups. A significantly higher number of BE cases (P < 0.05) showed goblet cell staining for MUC1 (55%) or MUC6 (32%) compared with patients with carditis with intestinal metaplasia (MUC1 14%, MUC6 7%) or antritis with intestinal metaplasia (MUC1 6%, MUC6 0%). BE also showed a higher frequency of MUC1 and MUC6 positivity in non-goblet columnar cells compared with carditis and antritis cases with intestinal metaplasia. Only cases of BE showed combined MUC1 and MUC6 staining (sensitivity 23%, specificity 100%). The sensitivity and specificity of MUC1 staining for BE are 55% and 96%, respectively, and for MUC6 staining 30% and 96%, respectively. Interestingly, normal gastric cardia mucosa also showed a significantly higher prevalence of MUC2 and MUC3 expression in glandular epithelium (29% and 38%, respectively) compared with the antrum (0% for both markers) (P < 0.05). In conclusion, MUC1 and MUC6 expression in BE is distinct from that of the cardia and antrum with intestinal metaplasia; thus, immunophenotyping for these markers may have some value in a subset of patients in helping to separate BE from patients with intestinal metaplasia of the cardia. Columnar epithelium in the "normal" gastric cardia has a partially intestinalized phenotype and, as a result, may represent an early form of metaplastic epithelium.

Cytokeratin 7/20 and mucin expression patterns in oesophageal, cardia and distal gastric adenocarcinomas

AIMS

The current study examined cytokeratin (CK)7 and 20 as well as MUC1-6 immunoprofiles in oesophageal, gastric and gastro-oesophageal junction (GOJ) adenocarcinomas. The aim was to compare expression patterns in these locations as aids to accurate classification of these morphologically similar carcinomas which all may involve the GOJ.

METHODS AND RESULTS

Tissue microarrays were constructed using tissue from 14 oesophageal, 78 gastric and 39 GOJ adenocarcinomas. Sections were immunostained with CK7, CK20, MUC1, MUC2, MUC5AC and MUC6. The results of this study showed no differences in CK7 and CK20 expression patterns in the three locations. MUC2 expression was higher proximally (43% of oesophageal, 28% of GOJ and 17% of gastric carcinomas) and MUC6 expression was higher distally (7% of oesophageal, 28% of GOJ and 15% of gastric carcinomas). MUC1 expression was associated with higher pTNM-stage.

CONCLUSIONS

CK 7/20 profiles have no role in distinguishing tumours of the three locations. Mucin expression patterns differed in oesophageal and gastric adenocarcinomas, although not sufficiently to classify individual cases. GOJ adenocarcinomas showed a mucin expression pattern that was partly 'gastric', and partly 'oesophageal'. MUC1 expression was associated with a higher pTNM stage.

Trends in incidence and prevalence of specialized intestinal metaplasia, barrett's esophagus, and adenocarcinoma of the gastroesophageal junction

Most available information on the epidemiology of Barrettacute;s esophagus (BE) relates to patients with long segments (> 3 cm) of specialized intestinal metaplasia (SIM). Its prevalence is 3% in patients undergoing endoscopy for reflux symptoms and 1% in those undergoing endoscopy for any clinical indication. The latter prevalence is similar to the 1% found in autopsy series. A "silent majority" with BE remain unrecognized in the general population. BE is more common in men, and the prevalence rises with age. Recent endoscopic series document a rise in the diagnosis of endoscopically apparent short segments (< 3 cm) of BE (SSBE). The prevalence of SSBE in both unselected and reflux patients is 8% to 12%. Specialized intestinal metaplasia at the cardia, below a normal-appearing squamocolumnar junction, has been reported to vary from 6% to 25% in patients presenting for upper endoscopy. Unlike patients with long segment Barrett's esophagus (LSBE), the role of gastroesophageal reflux disease in the pathogenesis of SSBE and SIM of the cardia is controversial. Recent data suggest that the etiology of SIM of the cardia might be secondary to Helicobacter pylori infection, although the role of other environmental factors cannot be ruled out. The incidence of adenocarcinoma of the esophagus and esophagogastric juction (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. LSBE and SSBE predispose to the development of adenocarcinoma of the esophagus and EGJ. The role of SIM of the cardia as a precursor lesion for EGJ adenocarcinoma is still unclear. The prevalences of dysplasia in LSBE and SSBE are around 6% and 8%, respectively. The incidence of adenocarcinoma in patients with LSBE is about 1 in 100 patient-years. Cancer risk for SSBE and SIM at the cardia is unknown. Smoking and obesity increase the risk for esophageal and EGJ adenocarcinomas.