Prevalence of Barrett's esophagus and expression of mucin antigens detected by a panel of monoclonal antibodies in Barrett's esophagus and esophageal adenocarcinoma in Japan

A simpler diagnostic algorithm of the Japan Esophageal Society classification for Barrett's esophagus-related superficial neoplasia

BACKGROUND

We previously developed a Japan Esophageal Society Barrett's Esophagus (JES-BE) magnifying endoscopic classification for superficial BE-related neoplasms (BERN) and validated it in a nationwide multicenter study that followed a diagnostic flow chart based on mucosal and vascular patterns (MP, VP) with nine diagnostic criteria. Our present post hoc analysis aims to further simplify the diagnostic criteria for superficial BERN.

METHODS

We used data from our previous study, including 10 reviewers' assessments for 156 images of high-magnifying narrow-band imaging (HM-NBI) (67 dysplastic and 89 non-dysplastic histology). We statistically analyzed the diagnostic performance of each diagnostic criterion of MP (form, size, arrangement, density, and white zone), VP (form, caliber change, location, and greenish thick vessels [GTV]), and all their combinations to achieve a simpler diagnostic algorithm to detect superficial BERN.

RESULTS

Diagnostic accuracy values based on the MP of each single criterion or combined criteria showed a marked trend of being higher than those based on VP. In reviewers' assessments of visible MPs, the combination of irregularity for form, size, or white zone had the highest diagnostic performance, with a sensitivity of 87% and a specificity of 91% for dysplastic histology; in the assessments of invisible MPs, GTV had the highest diagnostic performance among the VP of each single criterion and all combinations of two or more criteria (sensitivity, 93%; specificity, 92%).

CONCLUSION

The present post hoc analysis suggests the feasibility of further simplifying the diagnostic algorithm of the JES-BE classification. Further studies in a practical setting are required to validate these results.

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

OBJECTIVE

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

DESIGN

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

RESULTS

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

CONCLUSIONS

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

Low risk of esophageal adenocarcinoma among patients with ultrashort-segment Barrett's esophagus in Japan

OBJECTS

Ultrashort-segment Barrett's esophagus (USSBE; length of <1 cm) is very frequently diagnosed in Japan, but the cancer risk of USSBE is unknown. In this study, by retrieving endoscopic images, we retrospectively investigated the incidence of esophageal adenocarcinoma (EAC) by the grade of Barrett's esophagus (BE) and compared the findings with those of gastric cancer by the degree of endoscopic gastric atrophy in the same population.

METHODS

Among consecutive participants who had undergone endoscopy for an annual health checkup in 2014, the 9121 who had received at least one follow-up endoscopy by December 2020 were enrolled in this study. Using the retrieved endoscopic images, we retrospectively evaluated BE and gastric atrophy. Information on the subsequent occurrence of EAC and gastric cancer as of December 2020 was also collected. The incidence of cancer by the extent of BE and gastric atrophy was calculated and expressed as the percentage per year.

RESULTS

On reviewing the endoscopic image in 2014, 4190 (45.9%) were found to have been diagnosed with BE, of whom 3318 (36.4%) were judged to have USSBE. During an observation period of 54.1 (17.9) months, 89 gastric cancers and only two EACs were identified. The incidence of EAC in USSBE was 0.0068%/year, which was nearly as low as the incidence of gastric cancer in atrophy-free patients (0.0068% vs. 0.0059%/year).

CONCLUSIONS

Although the prevalence of USSBE is quite high (36.4%), the incidence of EAC in USSBE is very low (0.0068%/year). Accordingly, USSBE can be excluded from targets for endoscopic surveillance in Japan.

mAb Das-1 recognizes 3'-Sulfated Lewis A/C, which is aberrantly expressed during metaplastic and oncogenic transformation of several gastrointestinal Epithelia

INTRODUCTION

Multiple previous studies have shown the monoclonal antibody Das-1 (formerly called 7E12H12) is specifically reactive towards metaplastic and carcinomatous lesions in multiple organs of the gastrointestinal system (e.g. Barrett's esophagus, intestinal-type metaplasia of the stomach, gastric adenocarcinoma, high-grade pancreatic intraepithelial neoplasm, and pancreatic ductal adenocarcinoma) as well as in other organs (bladder and lung carcinomas). Beyond being a useful biomarker in tissue, mAb Das-1 has recently proven to be more accurate than current paradigms for identifying cysts harboring advanced neoplasia. Though this antibody has been used extensively for clinical, basic science, and translational applications for decades, its epitope has remained elusive.

METHODS

In this study, we chemically deglycosylated a standard source of antigen, which resulted in near complete loss of the signal as measured by western blot analysis. The epitope recognized by mAb Das-1 was determined by affinity to a comprehensive glycan array and validated by inhibition of a direct ELISA.

RESULTS

The epitope recognized by mAb Das-1 is 3'-Sulfo-Lewis A/C (3'-Sulfo-LeA/C). 3'-Sulfo-LeA/C is broadly reexpressed across numerous GI epithelia and elsewhere during metaplastic and carcinomatous transformation.

DISCUSSION

3'-Sulfo-LeA/C is a clinically important antigen that can be detected both intracellularly in tissue using immunohistochemistry and extracellularly in cyst fluid and serum by ELISA. The results open new avenues for tumorigenic risk stratification of various gastrointestinal lesions.

Prevalence of Barrett's Epithelium Shown by Endoscopic Observations with Linked Color Imaging in Subjects with Different H. pylori Infection Statuses

Objective This study was conducted to clarify the prevalence of short segment Barrett's esophagus (SSBE) using endoscopic observations with linked color imaging (LCI). In addition, the relationship between the presence of Barrett's epithelium (BE) and the status of H. pylori infection was investigated. Methods The study subjects were 3,353 individuals (2,186 men, 1,167 women; mean age 55.2±9.4 years old) whose status of H. pylori infection had been determined. An endoscopic observation using LCI was performed to examine the distal margin of palisade vessels and confirm the area of BE. The prevalence of BE ≥5 mm in length was investigated. Results BE was diagnosed in 1,884 (56.2%) subjects, with lengths of <10, 10-19, 20-29, and ≥30 mm found in 1,005, 851, 27, and 1, respectively. Its prevalence in H. pylori-negative, H. pylori-positive, and post-eradicated subjects was 41.7%, 64.4%, and 69.9%, respectively (p<0.001). The duration since successful eradication of H. pylori did not affect the prevalence of BE. The degree of gastric mucosal atrophy was higher in cases with BE (p<0.001), although negativity for H. pylori infection and mild gastric mucosal atrophy were significant factors for the development of longer BE. Conclusion A high prevalence of SSBE was noted when LCI was used to determine the area of BE, as the distal end of the palisade vessels was easily visualized. Negativity for H. pylori infection and mild gastric mucosal atrophy were not correlated with SSBE prevalence.

The global prevalence of Barrett's esophagus: A systematic review of the published literature

BACKGROUND

Determining the prevalence of Barrett's esophagus is important for defining screening strategies. We aimed to synthesize the available data, determine Barrett's esophagus prevalence, and assess variability.

METHODS

Three databases were searched. Subgroup, sensitivity, and meta-regression analyses were conducted and pooled prevalence was computed.

RESULTS

Of 3510 studies, 103 were included. In the general population, we estimated a prevalence for endoscopic suspicion of Barrett's esophagus of (a) any length with histologic confirmation of intestinal metaplasia as 0.96% (95% confidence interval: 0.85-1.07), (b) ≥1 cm of length with histologic confirmation of intestinal metaplasia as 0.96% (95% confidence interval: 0.75-1.18) and (c) for any length with histologic confirmation of columnar metaplasia as 3.89% (95% confidence interval: 2.25-5.54) . By excluding studies with high-risk of bias, the prevalence decreased to: (a) 0.70% (95% confidence interval: 0.61-0.79) and (b) 0.82% (95% confidence interval: 0.63-1.01). In gastroesophageal reflux disease patients, we estimated the prevalence with afore-mentioned criteria to be: (a) 7.21% (95% confidence interval: 5.61-8.81) (b) 6.72% (95% confidence interval: 3.61-9.83) and (c) 7.80% (95% confidence interval: 4.26-11.34). The Barrett's esophagus prevalence was significantly influenced by time period, region, Barrett's esophagus definition, Seattle protocol, and study design. There was a significant gradient East-West and North-South. There were minimal to no data available for several countries. Moreover, there was significant heterogeneity between studies.

CONCLUSION

There is a need to reassess the true prevalence of Barrett's esophagus using the current guidelines in most regions. Having knowledge about the precise Barrett's esophagus prevalence, diverse attitudes from educational to screening programs could be taken.

Prevalence, clinical characteristics, and risk factors of Barrett esophagus in Vietnamese patients with upper gastrointestinal symptoms

The current barrier for investigation of Barrett esophagus (BE) in Asia is diagnostic standardization, which is a challenge to identify its true risk factors. This study aimed to investigate the prevalence, clinical characteristics and risk factors of BE in Vietnamese patients with upper gastrointestinal symptoms.A cross-sectional study was conducted on consecutive outpatients who underwent upper gastrointestinal endoscopy. Endoscopically suspected esophageal metaplasia (ESEM) which was clearly visible at least 1 cm above the gastroesophageal junction at endoscopy was taken biopsy. At least 1 biopsy per 2 cm in tongues of ESEM and 4 biopsies per 2 cm of circumferential ESEM were taken. The diagnostic criterion for BE was replacement of the normal squamous epithelial lining by columnar epithelium confirmed by histology.A total of 1947 patients were recruited. Forty-seven out of 58 patients with ESEM were histologically confirmed BE. The prevalences of BE and hiatal hernia (HH) were 2.4% (95% confidence interval [CI], 1.7-3.1%) and 2.3% (95% CI, 1.6-2.9%), respectively. Heartburn and/or regurgitation presented in only 61.7% (95% CI, 46.4-75.5%) of patients with BE. In multivariate analysis, the only 2 factors significantly associated with BE were HH (OR 7.53; 95% CI, 3.13-18.11; P < .001) and typical reflux symptom (OR 2.07; 95% CI, 1.12-3.83; P = .020).BE is not uncommon in Vietnamese patients with upper gastrointestinal symptoms. In addition, typical reflux symptoms and HH are the risk factors for BE in Vietnamese.

Endoscopic submucosal dissection/endoscopic mucosal resection guidelines for esophageal cancer

The Japan Gastroenterological Endoscopy Society has developed endoscopic submucosal dissection/endoscopic mucosal resection guidelines. These guidelines present recommendations in response to 18 clinical questions concerning the preoperative diagnosis, indications, resection methods, curability assessment, and surveillance of patients undergoing endoscopic resection for esophageal cancers based on a systematic review of the scientific literature.

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

BACKGROUND AND AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Surgical treatment strategy for esophagogastric junction cancers based on the tumor diameter

BACKGROUND

The number of patients with esophagogastric junction (EGJ) cancers has tended to increase. However, no clear consensus on the optimum treatment policy has yet been reached.

METHODS

This study included patients diagnosed with adenocarcinoma of Sievert type II in whom resection was performed in our hospital. We performed a clinicopathological examination, and patients were divided into two groups by the tumor size: L group, tumor size ≥4 cm; and S group, tumor size < 4 cm. The clinical factors, such as nodal dissection and recurrence pattern, were then analyzed.

RESULTS

A total of 48 patients were diagnosed with ECJ cancers. The average tumor size was 55.1 mm, and 32 cases (66.7%) had tumors ≥4 cm. Metastasis to the mediastinum was noted in 4 cases (12.5%) in the L group but none in the S group. Recurrence in the upper or middle mediastinum lymph nodes was noted in 3 cases (9.4%) in the L group. The 5-year overall survival rates were 49.7 and 83.9% in the L and S groups, respectively.

CONCLUSIONS

As the tumor grows large, it is difficult to accurately judge EGJ on the image, and as a result it is difficult to understand the exact esophageal invasion distance of the tumor. Therefore, lymph node dissection including the upper mediastinum is considered vital, regardless of the degree of esophageal invasion.

Surveillance of patients with long-segment Barrett's esophagus: A multicenter prospective cohort study in Japan

BACKGROUND AND AIM

The incidence of esophageal adenocarcinoma (EAC) in cases with long-segment Barrett's esophagus (BE) has not been investigated in Japan. The aim of this study is to investigate the incidence of EAC in Japanese cases with long-segment BE prospectively.

METHODS

This is a multicenter prospective cohort study investigating the incidence rate of EAC in patients with BE with a length of at least 3 cm. Study subjects received index esophagogastroduodenoscopy at the time of enrollment, and they were instructed to undergo yearly follow-up esophagogastroduodenoscopy. Patients in whom EAC was diagnosed in the endoscopic examinations underwent subsequent treatment, and their prognosis was observed.

RESULTS

Of 215 enrolled patients, six (2.8%) were initially diagnosed with EAC at the enrollment. Among the remaining 209 patients, 132 received at least one follow-up esophagogastroduodenoscopy. In this follow-up, three EACs developed in 251 observed patient-years (incidence rate: 1.2% per year). Most of the EACs detected at the initial endoscopic examination (5/6, 83%) were already at advanced stages. Meanwhile, all the three lesions detected in the follow-up esophagogastroduodenoscopies were identified as early cancers and subjected to curative resection.

CONCLUSIONS

The incidence rate of EAC in Japanese cases with long-segment BE was calculated to be 1.2% in a year.

Prevalence of Barrett's Esophagus in Asian Countries: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

The prevalence and risk factors of Barrett's esophagus (BE) in Asian countries are unclear. Studies report a wide range of BE prevalence in Asian countries. We conducted a systematic review and meta-analysis to examine the prevalence of BE and its temporal changes and risk factors in Asian countries.

METHODS

Two investigators performed independent literature searches by using PubMed and EMBASE databases, and subsequent data abstraction for studies had to meet several set inclusion and exclusion criteria. Pooled BE prevalence was calculated by using a random-effect model. Estimates of relative risk for possible risk or protective factors were also calculated.

RESULTS

A total of 51 studies (N = 453,147), mainly from Eastern Asia, were included. The pooled prevalence of endoscopic BE was 7.8% (95% confidence interval, 5.0-12.1; 23 studies) and of histologically confirmed BE was 1.3% (95% confidence interval, 0.7-2.2; 28 studies). Most of histologic BE (82.1%) was short-segment BE (<3 cm). There was a trend toward an increase in prevalence of BE over time from 1991 to 2014, especially in Eastern Asian countries. Within BE cohorts, pooled prevalence of low-grade dysplasia, high-grade dysplasia, and esophageal adenocarcinoma was 6.9%, 3.0%, and 2.0%, respectively. Reflux symptoms, male sex, hiatus hernia, and smoking were associated with a significantly increased risk of histologic BE in patients with BE compared with patients without BE. However, half of the patients with histologic BE did not have reflux symptoms.

CONCLUSIONS

BE is not uncommon in Asian countries and seems to share similar risk factors and potential for neoplastic progression to those seen in Western countries.

Time series analysis of gastric acid secretion over a 20-year period in normal Japanese men

BACKGROUND

The gastric acid secretion level is an important determinant for the manifestation of the gastroesophageal reflux disease spectrum, finally leading to the development of esophageal adenocarcinoma (EAC). Although the incidence of EAC has remained low in Asia, understanding the recent trend in gastric acid secretion should be helpful in estimating future incidences of EAC in that area. We investigated the latest chronological change (1995-2014) in gastric acid secretion in normal Japanese patients.

METHODS

A total of 307 asymptomatic Japanese men who attended the clinic for annual endoscopic checkups from 1995 to 2014 were enrolled in this analysis. Gastrin-stimulated gastric acid secretion was estimated with the endoscopic gastrin test. The association between gastric acid secretion and chronological period was assessed with a multivariate linear regression analysis.

RESULTS

Overall gastric acid secretion gradually increased over the 20-year period in the entire cohort in the unadjusted analysis (p < 0.05). However, the apparent increase was largely related to the relative decreasing rate of H. pylori infection, which profoundly inhibited gastric acid secretion. Gastric acid secretion did not change over the 20-year period in H. pylori-negative subjects, and it showed only a mild increase during this period in H. pylori-positive subjects.

CONCLUSIONS

Considering that gastric acid secretion remained unchanged in H. pylori-negative Japanese men over a 20-year period at a level much lower than that in Occidental subjects, upper gastrointestinal disease profiles in the Japanese population will differ from those in Western countries in the post-H. pylori era.

Association between the body mass index and the risk of Barrett's esophagus in Japan

BACKGROUND

We investigated the association between long-segment Barrett's esophagus and obesity in the Japanese population in a multicenter case-control trial.

METHODS

One hundred thirteen patients with endoscopically detected Barrett's esophagus with a length of more than 2 cm and the same number of sex- and age-matched controls were prospectively enrolled. Barrett's esophagus was diagnosed based on the Prague C and M criteria. The body mass index (BMI) of the subjects was categorized into the following groups: normal, BMI <22.9; overweight, BMI 23.0-24.9, and obese, BMI >25.0. To determine the association between BMI and the risk of Barrett's esophagus, multivariate logistic regression analyses were performed.

RESULTS

The basically adjusted regression model adjusted for smoking and alcohol consumption revealed that overweight and obesity were significantly associated with an elevated risk of Barrett's esophagus (OR 2.4, 95% CI 1.2-4.7, and OR 2.5, 95% CI 1.3-4.6, respectively). The intensity of the association was not attenuated even after adjustment for gastroesophageal reflux disease-related parameters.

CONCLUSIONS

An increased BMI was associated with an increased risk for Barrett's esophagus through a gastroesophageal reflux-independent mechanism in the Japanese population. Further, unlike in Caucasian populations, being even slightly overweight with a BMI of 23.0-24.9 was an independent risk factor in the Japanese population.

Utility of endoscopy for diagnosis of barrett in a non-Western society: endoscopic and histopathologic correlation

Barrett esophagus is metaplastic transformation of esophageal squamous epithelium to columnar cells. A total of 1370 patients who had undergone upper endoscopy because of dyspeptic complaints were enrolled in the study. Age, sex, alcohol and smoking habits, body mass index, type and duration of symptoms (heartburn, epigastric pain, nausea, vomiting), and use of proton pump inhibitors were evaluated in all patients and recorded on standardized forms. Patients were grouped as normal esophagogastric junction, long-segment Barrett esophagus, and short-segment Barrett. Biopsies were taken from at least 6 points and examined histopathologically. Of the 1370 patients involved in the study, 748 (54.6%) were female and 622 (45.4%) were male. Mean age was 47.2 ± 15.30 years. Short-segment Barrett esophagus was detected in 16 patients, and long-segment Barrett was detected in 11 patients. Although Barrett esophagus was detected in 11 cases that were suspected to have Barrett during endoscopy, histopathology was negative in all cases that were not suspected to have Barrett. Barrett esophagus prevalence was significantly higher in people who used alcohol and tobacco and who had hiatal hernia. Although Barrett esophagus was detected in 40% of cases that were suspected to have Barrett during endoscopy, histopathology was negative in all cases that were not suspected to have Barrett. Barrett was detected in 40.7% of cases that were suspected to have Barrett during endoscopy; histopathology was negative in all cases that were not suspected to have Barrett. Senstivity of endoscopy is questionable in detection of short-segment Barrett.

Barrett esophagus: when to endoscope

Increasing interest in identifying an effective strategy for decreasing the burden of esophageal adenocarcinoma (EAC) has been fuelled by the rising EAC rates worldwide, the morbidity associated with esophagectomy, and the development of endoscopic methods for curing early-stage EAC. In the face of this enthusiasm, however, we should be cautious about continuing our current evidence-free approach to screening and one with unclear benefits and unclear costs to the community. The literature is increasingly recognizing that the value of traditional endoscopy for screening and surveillance of Barrett esophagus may be more limited than initially believed. A better understanding of the risk factors for Barrett esophagus and progression to dysplasia and a more individualized risk calculation will be useful in defining populations to consider for Barrett screening. The development of novel, nonendoscopic screening techniques and of less expensive endoscopic techniques holds promise for a cost-effective screening and surveillance method to curtail the increasing rates of EAC.

Barrett esophagus in Asia: same disease with different pattern

Barrett esophagus (BE) is considered to develop as a result of chronic gastroesophageal reflux disease (GERD) and to predispose to esophageal adenocarcinoma (EAC). However, the disease pattern of BE in Asia differs from that observed in the West. For example, in the West, the prevalence rates of BE and EAC have progressively increased, whereas although the prevalence rate of GERD is increasing in Asia, the prevalence rates of BE and EAC have remained low in most Asian countries. GERD, hiatal hernia, old age, male sex, abdominal obesity (visceral obesity), smoking, alcohol consumption, and kyphosis are known risk factors for BE in Asia, and most Asian patients have short-segment BE. Helicobacter pylori infection is more prevalent in Asia than in the West. We suggest larger studies with a prospective design be conducted to elaborate further the different patterns of BE in Asia.

Endoscopic resection (endoscopic submucosal dissection/endoscopic mucosal resection) for superficial Barrett's esophageal cancer

Recently developed endoscopic resection (endoscopic submucosal dissection [ESD]/ endoscopic mucosal resection) has dramatically changed the therapeutic approach for Barrett's esophageal cancer. The rationale for endoscopic resection is that lesions confined to the mucosal layer have negligible risk for developing lymph node metastasis and can be successfully eradicated by endoscopic treatment as a curative treatment with minimal invasiveness. According to some reports that analyzed the rate of lymph-node involvement relative to the depth of mucosal or submucosal tumor infiltration, endoscopic resection is clearly indicated for intramucosal carcinoma and might be extended to lesions with invasion into the submucosa (<200 μm, sm1) because of the low risk for lymph node metastasis. Most Japanese experts recommend ESD for Barrett's esophageal cancer after accurate diagnosis of the margin of cancer using narrow band imaging with magnifying endoscopy because of its high curative rate. However, few studies have evaluated the long-term outcomes of endoscopic resection for Barrett's esophageal cancer in Japan. Further investigations should be conducted to establish endoscopic resection for Barrett's esophageal cancer.

A substantial incidence of silent short segment endoscopically suspected esophageal metaplasia in an adult Japanese primary care practice

AIM: To determine the incidence and characteristics of endoscopically suspected esophageal metaplasia (ESEM) in a primary adult care institution.

METHODS: Eight hundred and thirty two consecutive individuals (mean age, 67.6 years) undergoing upper gastrointestinal endoscopy between January 2009 and December 2010 were included in this study. The diagnosis of ESEM was based on the criteria proposed by the Japan Esophageal Society, and was classified as long segment ESEM (3 cm or more) or short segment ESEM (< 3cm). Short segment ESEM was further divided into circumferential and partial types. Age, gender, hiatus hernia, esophagitis, gastroesophageal reflux disease (GERD)-suggested symptoms, and antacid medications were recorded as background factors. Esophagitis was graded according to the Los Angeles classification. Hiatus hernia was divided into absent and at least partially present.

RESULTS: Long and short segment ESEM were found in 0 and 184 (22.1%) patients, respectively (mean age of short segment ESEM patients, 68.3 years). Male gender and hiatus hernia were shown to be significant factors affecting short segment ESEM by both univariate (P = 0.03 and P = 9.9x10^-18) and multivariate [Odds ratio (OR) = 1.45; P = 0.04, and OR = 43.3; P = 1.5x10^-7)] analyses. Two thirds of patients with short segment ESEM did not have GERD-suggested symptoms. There was no correlation between short segment ESEM and GERD-suggested symptoms.

CONCLUSION: The incidence of short segment ESEM in our community practice seems higher than assumed in Asian countries. As GERD-suggested symptoms are a poor predictor of ESEM, endoscopists should bear in mind that silent short segment ESEM does exist and, in fact, was found in the majority of our patients.

Two distinct types of cancer of different origin may be mixed in gastroesophageal junction adenocarcinomas in Japan: evidence from direct evaluation of gastric acid secretion

BACKGROUND AND AIMS

Barrett's esophageal cancer is usually included in gastroesophageal (GE) junction adenocarcinoma in Japanese people. No study on the pathogenesis of Barrett's esophageal cancer in comparison with GE junction adenocarcinoma other than Barrett's esophageal cancer has been reported in Japan. The aim of this study was to evaluate the clinical and pathological characteristics and gastric acid secretion of Barrett's esophageal cancer and GE junction adenocarcinoma other than Barrett's esophageal cancer in Japanese subjects.

MATERIAL AND METHODS

Twenty-three patients with Barrett's esophageal cancer and 23 patients with GE junction adenocarcinoma other than Barrett's esophageal cancer were enrolled in this study. We evaluated and compared them by assessing the Helicobactor pylori (HP) infection status and gastric acid secretion using the endoscopic gastrin test (EGT).

RESULTS

In the patients with Barrett's esophageal cancer, no significant difference was found in the mean EGT value between HP-positive and -negative patients, but in the patients with GE junction adenocarcinoma other than Barrett's esophageal cancer, the mean EGT value in HP-positive patients was significantly lower than that in HP-negative patients.

CONCLUSION

Two distinct types of cancer of different origin may be mixed in GE junction adenocarcinomas. One is Barrett's esophageal cancer associated with high gastric acid secretion and reflux of gastric acid into the esophagus, the other is cancer resembling distal gastric cancer associated with gastric atrophy and low gastric acid secretion.

From GERD to Barrett's esophagus: is the pattern in Asia mirroring that in the West?

Gastroesophageal reflux disease (GERD) is a known predisposing factor for Barrett's esophagus. Amongst individuals with symptomatic GERD, the prevalence of Barrett esophagus is estimated to be more than 10%, and an individual with Barrett's esophagus is more likely than the general population to develop esophageal adenocarcinoma. In Western Europe and North America, incidence of esophageal adenocarcinoma had been on the upward trend for many decades. In comparison, although the prevalence of GERD and reflux esophagitis has increased several fold in some parts of Asia, the prevalence of esophageal adenocarcinoma and Barrett's esophagus remains generally low in the region. Rising incidence of esophageal adenocarcinoma has been observed in regions witnessing increasing prevalence of GERD. If the recent increase in prevalence of GERD in parts of urbanized Asia is any indication of the beginning of an upsurge in the incidence of Barrett's esophagus and associated adenocarcinoma, would we be witnessing a pattern of epidemiological shift mirroring that in the West? Given that more than 90% of Barrett's esophagus in Asian patients is of the short-segment type, which is reported to have lesser propensity to develop to adenocarcinoma, could the ongoing epidemiologic transition take Asia on the same trail as that which the West has taken? This article will draw on relevant findings from various parts of Asia and take an in-depth look at prevailing disease trends to see where Asia stands now in the changing epidemiology of GERD, Barrett's esophagus and associated adenocarcinoma.

Current status of Barrett's esophagus research in Asia

In Western countries, the epidemiology of esophageal cancer has changed considerably over the past decades with a rise in the ratio of adenocarcinoma to squamous cell carcinoma. Although the prevalence of gastroesophageal reflux is increasing in Asia, the prevalences of Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) have remained low in most Asian countries. The Asian Barrett's Consortium recently conducted a review of published studies on BE from Asia to assess the current status of BE research in Asia, and to recommend potential areas for future BE research in the region. Differences in study design, enrolled population, and endoscopic biopsy protocols used have led to substantial variability in the reported BE prevalence (0.06% to 19.9%) across Asia. In particular, some Japanese studies used diagnostic criteria that differed considerably from what was used in most Asian studies. As in Western countries, increased age, male sex, tobacco smoking, reflux symptoms, and erosive esophagitis have been found to be risk factors for BE in several case-control studies from Asia. The Prague C and M criteria, developed to provide better interobserver reliability in diagnosis and grading of BE, are currently under extensive evaluation in the Asian population. There is a need for standardized protocols for endoscopic and histopathologic diagnosis before initiating collaborative projects to identify etiologic determinants of BE and its ensuing malignant transformation. At present, data regarding the management and long-term outcome of BE are extremely limited in Asia. More studies of BE in this geographic area are warranted.

Gastroesophageal reflux disease in Asia: A historical perspective and present challenges

Gastroesophageal reflux disease (GERD), previously uncommon in Asia, has now become an important disease in the region. Although much variability exists between studies, most endoscopy-based studies show a prevalence of erosive esophagitis of more than 10%. Symptom-based studies also show a prevalence of 6-10%. Two longitudinal follow-up studies on GERD symptoms have shown an increase with time, and several endoscopy-based time trend studies have also shown a significant increase in erosive reflux esophagitis. Studies on Barrett's esophagus have been confounded by the description of short (SSBE) and long segment (LSBE) Barrett's esophagus. Great variation in prevalence rates has been reported. SSBE vary from 0.1% to more than 20% while LSBE vary from 1-2%. Of the putative causative factors, obesity has been the most important. Many studies have linked GERD-esophagitis as well as occurrence of reflux symptoms with an increase in body mass index (BMI), obesity, especially visceral or central obesity, and metabolic syndrome. A decline in Helicobacter pylori infection with growing affluence in Asia has been broadly thought to result in healthier stomachs and a higher gastric acid output resulting in reflux disease. However, variable results have been obtained from association and H. pylori eradication studies.

Prevalence of Barrett's esophagus remains low in the Korean population: nationwide cross-sectional prospective multicenter study

PURPOSE

In contrast to the Western population, the prevalence of Barrett's esophagus (BE) is rare in the Korean population. However, the recent increase in prevalence of gastroesophageal reflux disease (GERD) may affect the prevalence of BE. The aim of this study was to survey the prevalence of BE and evaluate its risk factors.

METHODS

Patients between 18 and 75 years of age who visited 11 Korean tertiary referral centers between April and July 2006 for routine upper endoscopic examination were surveyed using a symptom questionnaire. Biopsies were performed on the columnar lined epithelium (CLE) of the distal esophagus, and diagnosis was confirmed with detection of specialized intestinal metaplasia.

RESULTS

The study comprised 2,048 patients (mean age 51.4 years, 965 males). The frequency of heartburn or acid regurgitation was 8.7% and 13.1%, respectively. Reflux esophagitis was diagnosed in 10.1% of patients (207 patients); however, most patients had mild reflux. CLE was found in 82 patients; however, only one patient had long-segment CLE. The prevalence of BE was 1% (21 patients). The risk factors for BE were age (P = 0.006), presence of heartburn [odds ratio (OR) 4.33, 95% confidence interval (CI) 1.66-11.34, P = 0.007], acid regurgitation (OR 3.37, 95% CI 1.35-8.42, P = 0.01), sliding hernia (OR 6.21, 95% CI 1.78-21.72, P = 0.001), and reflux esophagitis (OR 10.28, 95% CI 4.31-24.50, P < 0.0001) on univariate analysis. On multivariate analysis, presence of typical reflux symptoms (P = 0.02) and reflux esophagitis (P < 0.001) were significant.

CONCLUSIONS

Prevalence of Barrett's esophagus remains low in Koreans; however, risk of developing BE has increased in patients with GERD symptoms and reflux esophagitis.

Frequency and risk factors for Barrett's esophagus in Taiwanese patients: a prospective study in a tertiary referral center

BACKGROUND

There is a paucity of epidemiologic data concerning Barrett's esophagus (BE) in Taiwan.

AIM

This study aimed to investigate the frequency of and risk factors for BE in self-referred Taiwanese patients undergoing diagnostic endoscopy.

METHODS

A total of 736 consecutive patients undergoing upper endoscopy for a variety of gastro-intestinal symptoms from February to October 2007 were evaluated. A standard questionnaire was used to record the clinical characteristics and patient symptoms. Gastro-esophageal reflux disease (GERD) was diagnosed using the Montreal definition, while the Los Angeles Classification and Prague Circumferential and Maximal Criteria were used to assess erosive esophagitis and BE, respectively. Four-quadrant biopsies were taken from endoscopically suspected esophageal metaplastic mucosa every 2 cm for histologic evaluation. Eight variables were tested using a logistic regression model to identify risk factors for BE in GERD patients.

RESULTS

GERD was diagnosed in 344 patients, with typical esophageal symptoms noted in 255, reflux chest pain syndrome in 107, and extra-esophageal syndrome in 51, while 27 were asymptomatic. The mean age of the GERD patients was 49.8 years and 55.5% of them were male. Thirty-six percent (123 of 344) demonstrated erosive esophagitis and 95% were classified as having Los Angeles grade A or B disease. BE was diagnosed in 13 patients (3.8% of GERD patients), three of whom had dysplastic mucosa. In the final analysis model, hiatal hernia (odds ratio [OR] = 4.7, 95% confidence interval [CI] = 1.3-17.7, P = 0.02) and GERD duration >5 years (OR = 4.2, 95% CI = 1.2-4.8, P = 0.03) were independent risk factors for the development of BE.

CONCLUSION

There is a 3.8% frequency of BE in Taiwanese GERD patients. Hiatal hernia and prolonged GERD duration are significant risk factors.

Diagnosis of endoscopic Barrett's esophagus by transnasal flexible spectral imaging color enhancement

BACKGROUND

The diagnosis of endoscopic Barrett's esophagus (BE) has been under discussion for the past decade because palisade vessels may be obscured by inflammation or the location of upper end of gastric fold may be diversely changed. The flexible spectral imaging color enhancement (FICE) system can reconstruct improved spectral images decomposed from ordinary endoscopic images with free selection of three wavelengths, and can provide non-magnified images with high light intensity.

METHODS

To evaluate whether the transnasal FICE system enables easier diagnosis of endoscopic BE, 72 patients with endoscopic BE were observed prospectively with a transnasal endoscope using both conventional images and FICE images. The visualization of palisade vessels and the identification of the demarcation between endoscopic BE mucosa and gastric mucosa were compared between FICE images and conventional endoscopic images, and the CIELAB color differences were calculated among palisade vessels, background BE mucosa and gastric folds.

RESULTS

Palisade vessels could be more clearly visualized in BE mucosa with transnasal FICE than with conventional endoscopy. Demarcation between whitish BE mucosa and the upper end of the brownish gastric mucosa could be clearly identified using transnasal FICE images. Greater color differences existed with FICE images between palisade vessels and background BE mucosa as well as between BE mucosa and gastric folds than with conventional images, leading to better contrasting images.

CONCLUSIONS

The transnasal FICE system enables clear visualization of palisade vessels and provides better contrasting images of the demarcation between the BE mucosa and the gastric mucosa, and thus contributes to easier diagnosis of endoscopic BE.

Barrett's esophagus and endoscopically assessed esophagogastric junction integrity in 1000 consecutive Turkish patients undergoing endoscopy: a prospective study

Barrett's esophagus (BE) appears to be more common in Western than in Asian countries. BE is a complication of gastroesophageal reflux disease (GERD). Anatomical abnormalities of the esophagogastric junction (EGJ) are an important factor in the pathogenesis of GERD. We aimed to determine the prevalence of BE in Turkey, which is geographically located between Europe and Asia, and to investigate the frequency of BE according to the degree of anatomical disruption in the EGJ. This prospective study was performed on 1000 consecutive patients referred for endoscopy for any clinical indication. All patients underwent a structured interview that assessed major symptoms of GERD (regurgitation and heartburn). BE was diagnosed when specialized intestinal metaplasia was detected histologically in the esophageal biopsy specimens. Endoscopically assessed integrity of the EGJ was classified as one of three types, as follows: 1 Normal EGJ. The endoscope shaft was gripped tightly by the cardia in retroflexed endoscopy, or it was gripped less tightly but the cardia was seen to open and close with respiration. 2 Widened EGJ. The cardia was open during all phases of respiration in retroflexed endoscopy, but there was no endoscopic evidence of hiatal hernia (HH) on the antegrade view. 3 HH. The axial length from the EGJ to the diaphragmatic hiatus was at least 2 cm. BE was found in 12 patients (1.2%). Normal EGJ was seen in 90.7% of patients, widened EGJ in 4.3%, and HH in 5%. Patients with widened EGJ had a significantly higher incidence of major reflux symptoms and erosive esophagitis compared with those with normal EGJ (P= 0.001). BE was found in 14% of patients with HH and in 0.5% of patients with a normal EGJ (P= 0.001). None of the patients with widened EGJ had BE. In terms of BE frequency, these patients did not differ significantly from those with normal EGJ (P= 0.793) but did differ significantly from those with HH (P= 0.014). The prevalence of BE was 1.2% in a Turkish population undergoing endoscopy for any reason. In terms of EGJ integrity, comparison of the groups showed that even in the absence of HH, patients with widening of the EGJ had an increased prevalence of major reflux symptoms and erosive esophagitis. However, histologically confirmed BE was not seen among patients with widened EGJ.

Clinicopathologic Characteristics of Barrett's Cancer in Korea

BACKGROUND/AIMS

The incidence of Barrett's cancer is increasing in Western countries, but there have been only a few case reports of this condition in Korea. The aim of this study was to elucidate the endoscopic and pathologic characteristics of Barrett's cancer in a single center in Korea.

METHODS

We retrospectively reviewed the demographic, endoscopic, and pathologic characteristics of six patients with Barrett's cancer, defined as a tumor centered above the esophagogastric junction and surrounded by Barrett's esophagus.

RESULTS

All six patients were male, and three (50%) were symptomatic. Barrett's cancer had developed from short-segment Barrett's esophagus in all patients. All tumors were located on the right side of the lower esophagus and showed hyperemic mucosal changes. Three patients were treated surgically and three by endoscopic resection. All cases had pathologic evidence of Barrett's cancer.

CONCLUSIONS

Early detection of Barrett's cancer requires meticulous endoscopic observations of subtle mucosal color and morphological changes around the esophagogastric junction.

Prevalence of Barrett's esophagus in individuals without typical symptoms of gastroesophageal reflux disease

BACKGROUND: Barrett’s esophagus, the major risk factor for esophageal adenocarcinoma, is detected in approximately 10%-14% of individuals submitted to upper endoscopy for the assessment of gastroesophageal reflux disease related symptoms. Prevalence studies of Barrett’s esophagus in individuals without typical symptoms of gastroesophageal reflux disease have reported rates ranging from 0.6% to 25%. AIM: To determine the prevalence of Barrett’s in a Brazilian population older than 50 years without typical symptoms of gastroesophageal reflux disease. METHODS: A total of 104 patients (51 men), mean age of 65 years, with an indication for upper endoscopy but without symptoms of heartburn and/or acid regurgitation (determined with a validated questionnaire) were recruited. Subjects submitted to upper endoscopic examination in the last 10 years or using antisecretory medication (proton pump inhibitors) during the last 6 months were not included. Methylene blue chromoscopy was performed during the endoscopic exam to facilitate identification of the metaplastic epithelium. RESULTS: Barrett’s esophagus was diagnosed endoscopically and confirmed by histology in four patients, all of them males. The metaplastic segment was short (less than 3 cm) and free of dysplasia in all patients. The prevalence of Barrett’s esophagus was 7.75% in the male population and 3.8% in the general population studied. CONCLUSION: Due to the low prevalence of Barrett’s esophagus found in the present study, associated with the finding of short-segment Barrett’s esophagus in all cases diagnosed and the absence of dysplasia in the material analyzed, endoscopic screening for Barrett’s esophagus in patients above the age of 50 without the classical symptoms of gastroesophageal reflux disease is not indicated for the Brazilian population.

Which landmark results in a more consistent diagnosis of Barrett's esophagus, the gastric folds or the palisade vessels?

BACKGROUND

The endoscopic landmark used to diagnose Barrett's esophagus differs between Japanese and Western endoscopists.

OBJECTIVE

To compare the degree of diagnostic variation in results achieved by Japanese endoscopists when using the palisade vessels as a landmark of the distal esophagus and when using the gastric folds; interobserver diagnostic concordance was evaluated.

DESIGN

Eighty-four endoscopists classified 30 patients with Barrett's esophagus by viewing projected endoscopic photographs. The endoscopists were asked to identify the distal end of the esophagus, first by using the Japanese criteria and later by using the gastric folds after an explanation of the Prague C&M Criteria. Endoscopists were divided into groups according to years in practice as an endoscopist, presence or absence of board certification from the Japan Gastroenterological Endoscopy Society, and whether they had taken any special endoscopic training courses on GERD. The kappa coefficient of reliability was calculated for each group.

RESULTS

The initial overall kappa value for all the endoscopists for the identification of the distal end of the esophagus was only 0.14, an unacceptably low value of concordance over and above chance agreement. The length of experience with diagnostic endoscopy, board license, or special training had no impact on the level of concordance. After an explanation of the C&M Criteria, however, there was a statistically significant improvement in the diagnostic concordance.

CONCLUSIONS

The upper end of the gastric folds, as used in C&M Criteria, may be a more suitable landmark than the palisade vessels for identifying the distal end of the esophagus by endoscopy.

Prevalence of and risk factors for Barrett's esophagus with intestinal predominant mucin phenotype

OBJECTIVE

Barrett's esophagus with the intestinal predominant mucin phenotype is considered to have a higher malignant potential than that with the gastric predominant mucin phenotype. The purpose of this prospective study was to investigate the prevalence of and risk factors for Barrett's esophagus with the intestinal predominant mucin phenotype in patients undergoing endoscopy.

MATERIAL AND METHODS

A total of 1699 consecutive patients undergoing esophagogastroduodenoscopy were enrolled in the study. A targeted biopsy was performed when endoscopically observed columnar-appearing esophagus was stained with crystal violet. The sample, histologically evidenced as Barrett's esophagus, was immunohistochemically evaluated and categorized as of either gastric or intestinal predominant mucin phenotype. All the patients were requested to complete the structured questionnaire indicating their symptoms and food consumption patterns. Prevalence of and risk factors for Barrett's esophagus with and without the intestinal predominant mucin phenotype were investigated.

RESULTS

Out of 1668 patients, 629 (37.7%) were found to have endoscopic Barrett's esophagus. In 333 out of 1668 patients (19.9%), histological studies were diagnostic of Barrett's esophagus. One hundred and six of these 333 patients (31.8%) had the intestinal predominant mucin phenotype. Age, male gender and the presence of hiatal hernia were confirmed by multivariate analysis as the independent predictors for the presence of Barrett's esophagus with the intestinal predominant mucin phenotype.

CONCLUSIONS

Barrett's esophagus with the intestinal predominant mucin phenotype was immunohistochemically found in 6.4% of all study patients. Older age, male gender and the presence of hiatal hernia were the risk factors for the presence of Barrett's esophagus with the intestinal predominant mucin phenotype.

Preservation of gastric acid secretion may be important for the development of gastroesophageal junction adenocarcinoma in Japanese people, irrespective of the H. pylori infection status

BACKGROUND

We have previously reported that Helicobacter pylori infection prevents reflux esophagitis (RE) and Barrett's esophagus (BE) by decreasing gastric acid secretion. Gastroesophageal (GE) junction adenocarcinoma, including Barrett's adenocarcinoma, has been thought to be a complication of gastroesophageal reflux disease (GERD). However, the relationship between H. pylori infection, gastric acid secretion, and GE junction adenocarcinoma has not yet been investigated in Japan. The aim of this study was to evaluate this relationship in the Japanese population.

METHODS

A total of 168 Japanese patients (RE alone: 80, short-segment BE (SSBE): 16, long-segment BE (LSBE): 20, GE junction adenocarcinoma: 12, distal early gastric cancer (EGC): 40; male/female = 106/62; mean age 61.5 yr) and 80 Japanese control subjects who had no localized lesions in the upper gastrointestinal tract (male/female = 43/37, mean age 58.1 yr) were enrolled for this study. The prevalence of H. pylori infection was determined by biopsy, the rapid urease test, and measurement of the serum H. pylori IgG antibody. Gastric acid secretion was assessed by the endoscopic gastrin test (EGT). RE was diagnosed according to the Los Angeles classification.

RESULTS

The prevalence of H. pylori infection in the patients with RE alone (30%) was significantly lower than that in control subjects (71.2%). There was also a tendency for the prevalence of H. pylori infection to be lower in patients with BE (SSBE, 18.7%; LSBE, 0%) when compared to that in patients with RE alone. On the other hand, while the prevalence of H. pylori infection in patients with GE junction adenocarcinoma (58.3%) was significantly lower than that in patients with EGC (87.5%), it tended to be higher than that in patients with RE alone or BE. The mean EGT value in patients with RE alone (3.74 mEq/10 min) was significantly higher than that in control subjects (1.83). The mean EGT value in patients with BE (SSBE, 4.74; LSBE, 4.76) tended to be even higher than that in patients with RE alone. The mean EGT value in patients with GE junction adenocarcinoma (3.94) was significantly higher than that in control subjects and patients with EGC (0.67), but it was comparable to that independent of the H. pylori infection status in patients with RE alone or BE.

CONCLUSION

Preservation of gastric acid secretion may be important for the development of GE junction adenocarcinoma in Japanese people, irrespective of the H. pylori infection status.

Prevalence of Barrett's esophagus in Korea

BACKGROUND

In contrast to Western countries, the prevalence of Barrett's esophagus (BE) is still believed to be very low in the Far East. The aim of the present paper was to assess the prevalence of BE in Korea.

METHODS

Nine hundred and ninety-two consecutive patients undergoing their first diagnostic upper gastrointestinal endoscopies due to various indications were included from four university hospitals in Korea. Esophagus of each patient was examined during insertion of the endoscope with minimum air inflation. From subjects who were found, during endoscopy, to have columnar-lined esophagus, at least two biopsy samples were taken from the columnar epithelium. Patients exhibiting specialized columnar epithelium on histological examination were diagnosed as having BE.

RESULTS

Among 992 patients, 108 cases (10.9%) were endoscopically diagnosed as short-segment BE, and three cases (0.3%) were endoscopically diagnosed as long-segment BE. However, only 36 patients (3.6%) met the histological criteria for BE. Among these patients, only one (0.1%) was histologically diagnosed as having long-segment BE. Reflux esophagitis, mostly in a mild degree, was found in 25.0% of the BE group, and 8.6% of the non-BE group (P = 0.0022). Hiatal hernias were more commonly found in the BE group than in the non-BE group (22.2% vs 8.9%, P = 0.0163).

CONCLUSIONS

Although the prevalence of BE in Korea appears to be lower than the reported rates from Western countries, it may not be as low as was previously thought.

Review article: Barrett's oesophagus and carcinoma in Japan

In Asia, oesophageal diseases, such as Barrett's oesophagus and oesophageal carcinoma, have traditionally been less common than in America and Europe. In recent years, however, the number of reported cases of these conditions in Japan has increased. Two large prospective studies, the Sendai Barrett's Esophagus Study (S-BEST) and the Far East Study (FEST), on the geographic prevalence of Barrett's oesophagus, have recently investigated the epidemiology of Barrett's oesophagus in Japan. Results from both studies showed that overall prevalence of the condition is lower than in the West: 0.9-1.2% in Japan compared with 1-4% in Europe and 5-12% in USA. Similar to the situation in the West, the condition was shown to be most prevalent in elderly male patients and least prevalent in patients with Helicobacter pylori. Adenocarcinoma of the oesophagus is still rare in this region, although there has been an increase in the annual death rate from 3.7 (1960) to 6.9 (1995) per 100,000 population. Risk factors for oesophageal carcinoma include a strong association with the prevalence of gastro-oesophageal reflux disease (GERD). With the increasing prevalence of GERD in the Japanese population, continued surveillance of changes in the epidemiology of columnar-lined oesophagus (a precursor of Barrett's oesophagus), Barrett's oesophagus and adenocarcinoma of the oesophagus is strongly recommended.

Systematic review: geographical and ethnic differences in gastro-oesophageal reflux disease

BACKGROUND

Many observers believe that gastro-oesophageal reflux disease is more common among white individuals compared with Asians and Afro-Caribbean subjects.

AIM

To perform a systematic review regarding geographical and ethnic factors in the prevalence of reflux symptoms, endoscopic oesophagitis, hiatus hernia and Barrett's oesophagus.

RESULTS

Differences in definitions and methodology make comparison between studies difficult. Overall, however, the community prevalence of reflux symptoms, as well as the prevalence of endoscopic oesophagitis, hiatus hernia and Barrett's oesophagus among patients undergoing upper endoscopy, were lower among Asian and Afro-Caribbean subjects compared with white individuals. There may also be a north-south gradient in the prevalence of gastro-oesophageal reflux disease among western countries. Gastro-oesophageal reflux disease may be moderately common in the Middle East. There are suggestions that the prevalence of gastro-oesophageal reflux disease is increasing in the Far East.

CONCLUSIONS

More data are required, especially from Africa, South America, the Middle East, and the Indian subcontinent. Suggestions are made regarding definitions and methodology to facilitate comparison between future studies from different countries.

Barrett's esophagus: prevalence and its relationship with dyspeptic symptoms

BACKGROUND AND AIM

Barrett's metaplasia is a premalign condition which plays a pivotal role in the development of esophageal adenocarcinoma. It is considered a complication of chronic gastroesophageal reflux disease. Although esophageal adenocarcinoma is an uncommon cancer, its incidence is rapidly increasing. The aims of the present study were to determine the prevalence of Barrett's metaplasia in outpatients referred for gastroscopy for upper gastrointestinal symptoms, and to clarify the relationship between Barrett's metaplasia and upper gastrointestinal symptoms.

METHODS

Three-hundred and ninety-five consecutive dyspeptic patients, never previously investigated, underwent gastroscopy and were enrolled into the study.

RESULTS

Barrett's metaplasia was detected in 29 patients (7.4%). The age-specific prevalence of Barrett's metaplasia increased with age. In multivariate analysis, Barrett's metaplasia was independently and positively related to age, sex and duration of symptoms, but not with upper gastrointestinal symptoms. In univariate analysis, Barrett's metaplasia was significantly more common in patients with antral intestinal metaplasia (24%) and presence of hiatal hernia (65.5%), compared with those with normal endoscopic findings (6.2% and 39.2%, respectively, p = 0.001).

CONCLUSION

Symptoms do not predict Barrett's metaplasia. Barrett's metaplasia is age-related and more common in patients with a longer duration of symptoms, presence of hiatal hernia and antral intestinal metaplasia.

Detection of sulfated glycoproteins in intestinal metaplasia: a comparison of traditional mucin staining with immunohistochemistry for the sulfo-Lewis(a) carbohydrate epitope

BACKGROUND

Premalignant Barrett's oesophagus (BO) and gastric intestinal metaplasia (IM) show phenotypic variability. Incompletely differentiated sulfomucin rich gastric IM (type III) may have increased malignant potential. The types of sulfated oligosaccharide structures present in IM, BO, and colon have not been fully characterised.

AIMS

To compare sulfo-Lewis(a) epitope tissue distribution with high iron diamine (HID) positive sulfomucin in metaplastic, dysplastic, and neoplastic tissues from oesophagus and stomach.

METHODS

Sections containing gastric IM or BO (some associated with dysplasia or adenocarcinoma) were stained by the HID/alcian blue (AB) method and immunohistochemically (antibody 91.9H) to detect sulfo-Lewis(a). Based on HID/AB staining, IM was subtyped into type I (complete) or types II and III (incomplete).

RESULTS

In total, 125 sections from 38 subjects were studied. Normal squamous oesophagus, normal gastric epithelium, and type I IM were negative for sulfomucin and sulfo-Lewis(a). In type II IM, occasional goblet cells were HID and sulfo-Lewis(a) positive, but sialomucin secreting (AB positive) columnar cells were sulfo-Lewis(a) negative. Type III IM was always sulfo-Lewis(a) positive. Sulfomucin staining in dysplasia and cancer was variable, but HID positive areas were always sulfo-Lewis(a) positive.

CONCLUSIONS

Sulfo-Le(a), which is expressed on colonic mucin, is invariably present on sulfomucins in gastric IM and BO. Its presence in incomplete variants of IM and its absence from type I IM emphasises the phenotypic differences between complete and incomplete forms of metaplasia. 91.9H immunostaining is useful in IM subtyping. Characterising the molecular basis of sulfo-Lewis(a) expression may help understand the process of aberrant differentiation.

Classification of Barrett's epithelium by magnifying endoscopy

BACKGROUND

The specialized columnar epithelium of Barrett's esophagus can be detected by obtaining random or 4 quadrant biopsy specimens at conventional endoscopy. However, little is known about the fine mucosal structure of specialized columnar epithelium.

METHODS

Thirty patients with Barrett's esophagus were studied by magnifying endoscopy. The fine mucosal pattern (pit pattern) of 67 regions in Barrett's mucosa was recorded and compared with methylene blue staining. Histologic, mucin immunohistologic, and cell proliferation analyses of biopsy specimens were performed in relation to the pit patterns determined by magnifying endoscopy.

RESULTS

Pit pattern was classified into 5 types. Tubular and villous pit patterns were not only characteristics of both specialized columnar epithelium and methylene blue absorption, but also possessed an intestinal mucin phenotype with a high Ki-labeling index, whereas other pit patterns (dot and straight) did not have specialized columnar epithelium and were categorized as the gastric phenotype. The long oval pit pattern had an intermediate phenotype between gastric and intestinal.

CONCLUSIONS

The classification of the superficial mucosal appearance of Barrett's epithelium by magnifying endoscopy reflects not only histologic features but also mucin phenotypes.