Preoperative prevalence of Barrett's esophagus in esophageal adenocarcinoma: a systematic review

Where are you and how do we find you? The dilemma of identifying Barrett's epithelium before adenocarcinoma of the esophagus

The incidence of esophageal adenocarcinoma in white males has been increasing steadily over the past decade. However, attempts to identify the precursor lesion, intestinal metaplasia of the esophagus, or early in-situ cancers have been dismal, with no increase in the diagnosis of early cancers over 9 years of follow-up, as noted in the study by Cooper et al. Important predictors of survival,such as a previous diagnosis of gastroesophageal reflux disease, endoscopy, and the diagnosis of intestinal metaplasia, continue to represent a minority of patients who present with esophageal adenocarcinoma. A discussion on the possible pathophysiology, and reasons for the poor diagnostic yields in spite of performing more endoscopies, are presented. It may be that most patients are relatively asymptomatic, or have very distal, endoscopically imperceptible intestinal metaplasia. Over time, factors that encourage localized, distal esophageal reflux may be the insidious culprit that leads to intestinal metaplasia.

Risk factors for the detection of Barrett's esophagus in patients with erosive esophagitis

BACKGROUND

Barrett's esophagus (BE) results from metaplastic healing of injured esophageal mucosa after erosive esophagitis (EE).

OBJECTIVE

Our purpose was to determine whether severity of esophagitis, indication for endoscopy, or proton pump inhibitor treatment affects the subsequent incidence of BE diagnosis in patients found to have EE on EGD performed for any indication.

DESIGN

We identified patients with primary or secondary International Classification of Diseases, 9th revision diagnosis codes of EE from 1996 to 2006 who had at least 2 EGDs on record. Patients with prevalent BE on the first EGD were excluded.

SETTING

Inpatients and outpatients at Stanford University and Palo Alto Veterans Affairs Health Care System.

INTERVENTIONS

Retrospective review of EGD and pathology reports to confirm BE.

MAIN OUTCOME MEASUREMENTS

Detection of BE after diagnosis of EE.

RESULTS

A total of 1095 patients were identified between 1996 and 2000, and 102 (9%) were included. Sixty-two (61%) patients were veterans, 87 (85%) were male, and 83 (81%) were white. The mean (+/-SD) age was 58 +/- 14 years (range 24-83 years). BE was detected in 9 (9%) patients (95% CI, 4.5%-17.6%) over a mean of 13.3 +/- 5.7 months (range 1-53.5 months), and all had prior grade 4 esophagitis. The mean BE length was 4 +/- 1.8 cm (range 1-18 cm). Six patients had upper GI bleeding as the indication for EGD, whereas the other 3 complained of dysphagia. The association of grade 4 esophagitis (P = .01) and GI hemorrhage (P = .01) to the subsequent detection of BE was highly statistically significant.

LIMITATIONS

Retrospective study, small number of patients with BE after EE. All patients were receiving care at tertiary medical centers.

CONCLUSIONS

BE was detected in 9% of patients with prior EE and was detected exclusively on follow-up of patients with severe esophagitis. The majority of the patients found to have BE had upper GI bleeding as the presentation for EGD.

Trends in Barrett's esophagus diagnosis in Southern Europe: implications for surveillance

The incidence of Barrett's esophagus (BE) and esophageal adenocarcinoma has increased in Western countries in recent decades. The aim of this study is to describe the changes in incidence and prevalence of BE diagnosis, dysplasia, and adenocarcinoma development in BE patients in a South-European Mediterranean area. Retrospective population-based analyses of endoscopy and pathology reports from 1976 to 2001 was performed. Data from patients with diagnosis of BE and/or esophageal carcinoma were collected. The study period was divided in four quartiles for statistical calculations; parametric and nonparametric tests were used. A 6.9-fold increase was found in the diagnosis of long-segment BE from the first to the fourth quartile, and a 9.3-fold increase in short-segment BE from 1995 to 2000, in contrast to a much smaller increase of 1.9-fold increase in the number of upper gastrointestinal endoscopies. The adjusted incidence of BE diagnosis increased from 0.73 to 9.73 cases/100,000 (first to fourth quartile, respectively) and the adjusted prevalence from 6.51 to 76.04 cases/100,000 (1985-2001). The incidence of dysplasia was 2.13% per year (95% confidence interval: 0.05-11.3%) - 1.78% for low-grade dysplasia and 0.36% for high-grade dysplasia - giving a total incidence of 1 per 47 patient-years. The incidence of adenocarcinoma during follow-up was 0.48% per year (95% confidence interval: 0.006-2.62%), for an incidence of 1 per 210 patient-years. Nineteen patients with BE (14 long-segment BE, 5 short-segment BE) were diagnosed with esophageal adenocarcinoma, with eight being diagnosed during endoscopic surveillance. Only 14 (8%) adenocarcinoma patients diagnosed during the study period had a history of BE. BE diagnosis has dramatically increased over recent decades in our population, unrelated to an increase in endoscopies. Progression to low-grade dysplasia and adenocarcinoma is rare. Surveillance may have a low impact on the survival of adenocarcinoma patients in Southern Europe.

Loss of heterozygosities in Barrett esophagus, dysplasia, and adenocarcinoma detected by esophageal brushing cytology and gastroesophageal biopsy

BACKGROUND

Esophageal brushing cytology (EBC) and gastroesophageal biopsy (GEB) are complementary procedures for the evaluation of gastroesophageal lesions that help guide surveillance and treatment.

METHODS

The authors investigated loss of heterozygosity (LOH) of 17 microsatellite repeat markers near tumor suppressor genes in gastroesophageal lesions on 34 concomitant EBCs and GEBs.

RESULTS

The results indicated that there was progressive accumulation of LOHs toward malignant transformation. EBC samples a greater area than GEB, and more LOHs are detected by EBC than GEB. The combination of cytomorphology and detection of LOHs can improve diagnostic accuracy and is a more useful methodology with which to evaluate gastroesophageal lesions than either EBC or GEB alone. The authors also found that LOHs at 1p36, 9p21, and 17p13 may play an important role in Barrett esophagus (BE), LOHs at 10q23, 17p13, and 17q12 in low-grade dysplasia (LGD), LOHs at 5q23 and 17q21 in high-grade dysplasia (HGD), and LOHs at 5q23 and 21q22 in adenocarcinoma.

CONCLUSIONS

Detection of LOHs targeting tumor suppressor genes can be useful in evaluating gastroesophageal lesions, studying oncogenesis of gastroesophageal adenocarcinoma, and, in combination with EBC and GEB, determining surveillance for BE and LGD and/or treatment for HGD and adenocarcinoma.

The association between body mass index and Barrett's esophagus: a systematic review

Biological plausibility and evidence from case series indicate that an increased body mass index could be a risk factor for Barrett's esophagus. The aim of this study was to assemble and appraise the available evidence on the association of body mass index and Barrett's esophagus in a narrative approach. A systematic literature review identified a nested case-control study and 10 case-control studies, with sample sizes of between 129 and 953. Overall, cases were on average older than controls, more often male and white, but did not differ with regards to body mass index. An increased body mass index (> or =30 and > or =35 kg/m(2)) was associated with greater risk of Barrett's esophagus in four studies (odds ratio range: 2.0-4.0). These studies, however, did not adjust for symptoms suggestive of gastroesophageal reflux disease. No significant association was reported in the other six studies. To conclude, the existing evidence on the association between body mass index and risk of Barrett's esophagus relates primarily to case-control studies and is inconsistent. Gastroesophageal reflux symptoms can be a potential confounder and further research should better address this issue. Evidence from cohort studies may help shed further light on this putative association, which is of relevance to public health and cancer control.

Screening, surveillance, and prevention for esophageal cancer

The incidence of esophageal cancer, especially esophageal adenocarcinoma, is increasing and its high mortality rate is a notable fact. Improving survival rates of this disease depend on earlier detection through screening and surveillance; however, standard diagnostic modalities, such as endoscopy with biopsy, have several limitations as screening tools, including low negative predictive value and relatively high cost. Recently developed biomarkers such as FISH and improved imaging techniques, may help overcome current problems and provide improved screening and surveillance for esophageal cancer.

Prevalence of Barrett's esophagus in patients with or without GERD symptoms: role of race, age, and gender

BACKGROUND

Gastroesophageal reflux disease is associated with a significantly increased risk of Barrett's esophagus (BE) and adenocarcinoma of the esophagus. Racial differences in the prevalence of BE are controversial. Our purpose was to study the prevalence of Barrett's esophagus in patients with and without gastroesophageal reflux disease (GERD) symptoms, and the differences between these two groups in terms of race, age, and sex.

METHODS

Esophagogastroduodenoscopy (EGD) reports from the PENTAX EndoPRO database for the Endoscopy Unit at the University of Texas Medical Branch from 2005 to 2007 were reviewed. Four hundred and ten patients who underwent upper endoscopy because of GERD symptoms that were not responding to proton pump inhibitor (PPI) therapy or with alarm symptoms and 4,047 patients undergoing upper endoscopy for other reasons without GERD symptoms were identified.

RESULTS

BE was significantly more common among males. The prevalence of BE was higher in patients with GERD symptoms than those without GERD symptoms. Overall, more cases of BE, dysplasia, and adenocarcinoma were found among the patients without GERD symptoms than those that underwent endoscopy because of GERD symptoms. The prevalence of BE among Caucasian, African American, Hispanic, and "other" groups with GERD symptoms were 5%, 2.56%, 4.4%, and 0%, respectively. The prevalence of BE among these racial groups without GERD symptoms were 1.9%, 0.9%, 1.57%, and 0.8%, respectively. The association between race and BE was not statistically significant (df = 3, P = 0.2628), including after adjusting for the presence of GERD symptoms (df = 3, P = 0.2947). Patients without GERD symptoms that presented with BE were significantly older than the patients without BE (P < 0.01).

CONCLUSIONS

BE is a male-dominant disease. The prevalence of Barrett's esophagus was not significant different among Caucasian, Hispanics, and African Americans. Most of the patients with BE, dysplasia, and adenocarcinoma did not have GERD symptoms.

[Review of the association between obesity and gastroesophageal reflux and its complications]

Esophageal adenocarcinoma and its precursor Barrett's esophagus are increasing in incidence in western populations. Gastroesophageal reflux and high body mass index (BMI) are known risk factors. Studies about Barrett's esophagus in obese patients have emphasised the role of central adiposity as a stronger risk factor than BMI in the development of specialized intestinal metaplasia and subsequently esophagus adenocarcinoma. The proinflammatory impact of adipocytokines of the abdominal fat associated with the metabolic syndrome is also relevant. Except cardiovascular diseases, type 2 diabetes and non alcoholic steatohepatitis, abdominal obesity and metabolic syndrome are responsible of an increase of prevalence of esophageal adenocarcinoma, but also other cancer sites. In this review, we study the up to date main epidemiologic and physiopathologic data concerning this association that could be important in future for a preventive action in obese patients, especially when metabolic syndrome is present.

Barrett's esophagus in 2008: an update

With the rising incidence and overall poor prognosis of esophageal adenocarcinoma (EA) there is great interest in furthering our understanding of Barrett's esophagus, the precursor lesion for most cases of EA. The best available evidence from true population-based analysis suggests that the prevalence of Barrett's is 1.6%. In addition, nearly half of the patients with Barrett's are asymptomatic. Several risk factors for development of Barrett's have been identified including gastro-esophageal reflux disease (GERD), central obesity, H. pylori eradication, and male gender. The precise incidence of progression from Barrett's to esophageal adenocarcinoma is not known, but it probably is less than 0.5% per year, and our ability to predict who is at highest risk for progression remains poor. The degree of dysplasia is currently used as a marker for risk of progression to cancer though there is increasing evidence that biomarkers and level of genetic instability may provide better predictive measures. Intensive acid-suppression and COX-2 inhibition are potential strategies to reduce the risk of progression, though definitive studies are needed. Endoscopic surveillance remains the mainstay of management for non-dysplastic and low grade dysplasia Barrett's. The advent of various endoscopic ablative therapies has provided a promising alternative to surgery for Barrett's patients with high grade dysplasia (HGD).

Chemoprevention of oesophageal cancer and the AspECT trial

Oesophageal cancer is on the rise and often present in an advanced state. Advances in surgical techniques, chemotherapy and radiotherapy have not changed the prognosis of oesophageal cancer over the last 20 years. With the unravelling of molecular biology of carcinogenesis in the oesophagus, there is a need for a paradigm shift from cancer treatment to prevention. Barrett's oesophagus is the commonest pre-malignant condition for development of oesophageal adenocarcinomas and is eminently suitable for the study of chemoprevention strategies. Now in its third year, the AspECT trial is the biggest, multicentre, randomised controlled clinical trial looking at the long-term chemoprevention effect of esomeprazole with or without aspirin. More than 85% of the participants tolerated the medications at the initial intended doses, and the drop-out rate has been 7%; the interim analysis is due in 2011.

Should patients with Barrett's oesophagus be kept under surveillance? The case for

Oesophageal adenocarcinoma is associated with high mortality rates and its incidence is increasing more rapidly than any other gastrointestinal cancer in the Western world. Several factors, including gastro-oesophageal reflux disease, smoking, alcohol and male gender, are associated with oesophageal adenocarcinoma but none can be used to identify accurately those individuals who will develop adenocarcinoma. It is generally accepted that oesophageal adenocarcinoma arises predominantly in Barrett's oesophagus and it is arguable that Barrett's oesophagus is currently the only clinically useful predictor of oesophageal adenocarcinoma. Surveillance - periodic testing to detect adenocarcinoma or its precursor, high grade dysplasia - is widely recommended for patients with Barrett's oesophagus with the aim of reducing mortality from oesophageal adenocarcinoma. The annual incidence of oesophageal adenocarcinoma in patients with Barrett's oesophagus is 0.5%-1.0% although there is marked variation between studies, attributable variously to publication bias, concurrent acid suppression therapy and differences in patient characteristics. There is limited evidence that surveillance reduces the incidence of oesophageal adenocarcinoma or consequent mortality and the cause of death for patients undergoing surveillance is often unrelated to oesophageal disease. There are, nonetheless, observational studies which suggest that surveillance is associated with earlier detection of malignancy and a reduction in mortality; in addition, data from modelling studies suggest that surveillance can be cost-effective. Furthermore, the advent of new, non-surgical treatments (endoscopic mucosal resection, photodynamic therapy, argon plasma coagulation) for high grade dysplasia and early cancer has reduced the risks associated with therapy for disease detected during surveillance. Surveillance programs have high drop out rates and, for patients who continue surveillance, adherence to standard, published protocols is highly variable. The establishment of specialist Barrett's oesophagus surveillance programs, with coordinator support, has considerable potential to improve adherence to current guidelines, pending the acquisition and publication of data from ongoing studies of chemoprophylaxis and surveillance in the management of Barrett's oesophagus. In consequence, although there is a paucity of data providing unequivocal demonstration of benefit, there is no proof that surveillance is ineffective. It is, therefore, appropriate to offer surveillance for Barrett's oesophagus in accordance with locally-applicable published guidelines after a full informed discussion of the risks and benefits of surveillance and therapy; continued participation should be reviewed regularly to accommodate changes in the patient's health and expectations.

Gastro-oesophageal reflux, medical resource utilization and upper gastrointestinal endoscopy in patients at risk of oesophageal adenocarcinoma

BACKGROUND

Early identification of patients at risk of oesophageal adenocarcinoma (OAC) might improve survival.

AIM

To assess the medical resource utilization in the 3 years before OAC diagnosis as potential markers for early identification and intervention.

METHODS

We identified 65 incident OAC within the Integrated Primary Care Information database. For comparison, we randomly selected 260 age- and gender-matched population controls. We abstracted the use of gastric acid inhibitors, general practitioner (GP) and specialist care, and gastroscopies in the 3 years before the detection of OAC.

RESULTS

Approximately 20% of the cases used gastric acid inhibitors in the third and second year before OAC, which increased to almost 50% in the last year, compared to approximately 10% among controls. Only in the 6 months before OAC, the proportion of patients visiting a GP (97%) or specialist (41%) increased compared to controls. Of 13 gastroscopies performed in the 3 years, six (46%) were not suspect for a malignancy.

CONCLUSIONS

Only a minority of all OAC patients used acid inhibitors before diagnosis. The use of medical care between cases and controls differed only in the final year before OAC diagnosis. Detection of early neoplastic changes proves to be difficult.

Management of Barrett's esophagus in the UK: overtreated and underbiopsied but improved by the introduction of a national randomized trial

OBJECTIVES

To assess the variation in practice of Barrett's esophagus (BE) management in comparison with accepted international guidelines before and after the introduction of a large BE randomized controlled trial (RCT) with protocols including those of tissue sampling.

DESIGN

A validated anonymized questionnaire was sent to 401 senior attending gastroenterologists asking for details of their current management of BE, especially histological sampling. Of the 228 respondents, 57 individuals (each from a different center) were in the first group to enter the ASPirin Esomeprazole (BE) Chemoprevention Trial (AspECT), and we assessed change in practice in these centers.

RESULTS

Ninety percent of specialists did not take adequate biopsies for histological diagnosis. Furthermore, 74% would consider aggressive surgical resection for prevalent cases of high-grade dysplasia in BE as their first-line choice despite the associated perioperative mortality. Ninety-two percent claim their lack of adherence to guidelines is because there is a need for stronger evidence for surveillance and medical interventions. Effect of the AspECT trial: Those clinicians in centers where the AspECT trial has started have improved adherence to ACG guidelines compared with their previous practice (P < 0.05). BE patients now get 18.8% more biopsies compared with previous practice, and 37.7% if the patient is entered into the AspECT trial (P < 0.01).

CONCLUSIONS

This large study indicates both wide variation in practice and poor compliance with guidelines. Because optimal histology is arguably the most important facet of BE management, the improvement in practice in centers taking part in the AspECT trial indicates an additional value of large international RCTs.

Tethered capsule endoscopy, a low-cost and high-performance alternative technology for the screening of esophageal cancer and Barrett's esophagus

Esophageal cancer is currently the fastest growing cancer in the United States. To help combat the recent rise in morbidity, our laboratory has developed a low-cost tethered capsule endoscope system (TCE) aimed at improving early detection of esophageal cancer. The TCE contains a resonant fiberoptic laser scanner (1.6 mm O.D.) which fits into 6.4-mm easy-to-swallow capsule at the distal tip. The tethered portion contains a single mode optical fiber multiplexed to three laser diodes at the proximal end. This design offers two main advantages over current endoscope technology. First, because of its small size, the TCE can be swallowed with minimal patient discomfort, thereby obviating sedation. Second, by imaging via directed laser light, the TCE is strategically positioned to employ several burgeoning laser-based diagnostic technologies, such as narrow-band, hyperspectral, and fluorescence imaging. It is believed that the combination of such imaging techniques with novel biomarkers of dysplasia will greatly assist in identifying precancerous conditions such as Barrett's esophagus (BE). As the probe is swallowed, the fiber scanner captures high resolution, wide-field color images of the gastroesophageal junction (500 lines at 0.05-mm resolution) currently at 15-Hz frame rate. Video images are recorded as the capsule is slowly retracted by its tether. Accompanying software generates panoramic images from the video output by mosaicing individual frames to aid in pattern recognition. This initial report describes the rationale for the unique TCE system design, results from preliminary testing in vitro and in vivo, and discussion on the merits of this new platform technology as a basis for developing a low-cost screening program for esophageal cancer.

Epidemiological trends in oesophageal cancer in the Nordic countries

OBJECTIVE

The incidence rates of oesophageal cancer vary more than those of any other cancer, world-wide. The aim of this study was to examine the epidemiological features of oesophageal cancer in the Nordic countries.

MATERIAL AND METHODS

Epidemiological data from the Nordic Cancer Registry (NORDCAN Database, http://www.ancr.nu/nordcan.asp) were used for the study analysis.

RESULTS

From 1971 to 2000 in the Nordic countries, 18,034 oesophageal cancers were detected in males and 8216 in females. In males, the incidence rates (world age standardized incidence per 100,000) of oesophageal cancer in 1971-75 and 1996-2000 were 2.7 and 6.0 in Denmark, 4.2 and 3.2 in Finland, 3.4 and 5.6 in Iceland, 2.6 and 3.3 in Norway, and 2.9 and 3.3 in Sweden, respectively. In females, the corresponding figures were: Denmark 1.1 and 1.8, Finland 3.1 and 1.3, Iceland 2.5 and 1.3, Norway 0.7 and 0.9, and Sweden 1.1 and 1.0. Each Nordic country showed a significant geographical variation in the incidence of oesophageal cancer. In both males and females the incidence curves began rising after 40 years of age, but significantly more steeply in males than in females. Over the study period, oesophageal cancer mortality increased from 2.97 to 3.68 per 100,000 in males but decreased from 1.30 to 1.08 in females. The incidence rates of oesophageal adenocarcinoma increased in males in all Nordic countries, and the increase was most marked in Denmark. The incidence of oesophageal adenocarcinoma also increased among Danish females, but compared with males, the incidence rate remained significantly lower.

CONCLUSIONS

The time trends in incidence of oesophageal cancer differ between the Nordic countries, and there has also been geographical variation within them. On a global comparison, the incidence rates of oesophageal cancer are low in the Nordic region. Oesophageal cancer is a male-predominant disease in all Nordic countries, and the incidence rates of oesophageal adenocarcinoma have increased in males and Danish females.

[Surgical treatment of high-grade dysplasia in Barrett's esophagus]

INTRODUCTION

Barrett's esophagus undergoes malignant transformation in 0.5-1% of patients per year following the sequence of low-grade dysplasia, high-grade dysplasia and adenocarcinoma. The aim of the present study was to present our experience in the surgical treatment of Barrett's esophagus with high-grade dysplasia.

PATIENTS AND METHOD

Of a group of 128 patients with a diagnosis of Barrett's esophagus, 8 (6.2%) developed high-grade dysplasia during a median follow-up of 7 years (2-25). A further 5 patients with high-grade dysplaing out side the study were referred for evaluation and surgical treatment. Eight patients were under medical treatment with omeprazole (40 mg daily) while the remaining 5 patients had undergone open Nissen fundoplication, with a diagnosis of high-grade dysplasia at a median of 5 years (1-16) after treatment initiation. After confirmation of the diagnosis by a second pathologist and tumoral staging, transthoracic esophagectomy with anastomosis at the apex of the thorax was performed in all patients.

RESULTS

Postoperative mortality was nil. Morbidity was 36% (5 patients). Definitive histological analysis of the surgical specimen revealed high-grade dysplasia in 7 patients (54%) and adenocarcinoma in 6 (46%). All patients remain alive after a median follow-up of 4.7 years (1-14).

CONCLUSIONS

In patients with Barrett's esophagus with high-grade dysplasia, the best therapeutic option is surgical resection, which can be performed with nil mortality in experienced centers. In almost half of surgical patients, the surgical specimen shows adenocarcinoma. Five-year survival is higher than 90%.

Relationship between Barrett's esophagus and cardia adenocarcinoma

The incidence of cardia adenocarcinoma (CA) has been increasing during the past few decades. CA and esophageal adenocarcinoma (EA) are known to share the same epidemiologic features. Barrett's esophagus (BE) is judged to be the precursor of EA. Thus, the question of whether BE is a risk factor for CA is currently much discussed. In this review, we describe the progress in the study of CA, and the relationship between CA and BE.

Radiochemotherapy of esophageal cancer

Cancer of the esophagus continues to be a threat to public health. The common practice is esophagectomy for surgically resectable tumors and radiochemotherapy for locally advanced, unresectable tumors. However, local regional tumor control and overall survival of esophageal cancer patients after the standard therapies remain poor, approximately 30% of patients treated with surgery only will develop local recurrence, and 50% to 60% patients treated with radiochemotherapy only fail local regionally due to persistent disease or local recurrence. Esophagectomy after radiochemotherapy or preoperative radiochemotherapy has increased the complete surgical resection rate and local regional control without a significant survival benefit. Induction chemotherapy followed by preoperative radiochemotherapy has produced encouraging results. In addition to patient-, tumor-, and treatment-related factors, involvement of celiac axis nodes, number of positive lymph nodes after preoperative radiochemotherapy, incomplete pathologic response, high metabolic activity on positron emission tomography scan after radiochemotherapy, and incomplete surgical resection are factors associated with a poor outcome. Radiochemotherapy followed by surgery is associated with significant adverse effects, including treatment-related pneumonitis, postoperative pulmonary complications, esophagitis and pericarditis. The incidence and severity of the adverse effects are associated with chemotherapy and radiotherapy dosimetric factors. Innovative treatment strategies including physically and biologically molecular targeted therapy is needed to improve the treatment outcome of patients with esophageal cancer.

Gene expression profiling of esophageal cancer: Comparative analysis of Barrett's esophagus, adenocarcinoma, and squamous cell carcinoma

Esophageal cancer is a particularly aggressive tumor with poor prognosis, however, our current knowledge of the genes and pathways involved in tumorigenesis of the esophagus are limited. To obtain insight into the molecular processes underlying tumorigenesis of the esophagus, we have used cDNA microarrays to compare the gene expression profiles of 128 tissue samples representing the major histological subtypes of esophageal cancer (squamous cell carcinoma and adenocarcinoma (ADC)) as well as Barrett's esophagus (BE), the precursor lesion to ADC, and normal esophageal epithelium. Linear discriminant analysis and unsupervised hierarchical clustering show the separation of samples into 4 distinct groups consistent with their histological subtype. Differentially expressed genes were identified between each of the tissue types. Comparison of gene ontologies and gene expression profiles identified gene profiles specific to esophageal cancer, as well as BE. "Esophageal cancer clusters," representing proliferation, immune response, and extracellular matrix genes were identified, as well as digestion, hydrolase, and transcription factor clusters specific to the columnar phenotype observed during BE and esophageal ADC. These clusters provide valuable insight into the molecular and functional differences between normal esophageal epithelium, BE, and the 2 histologically distinct forms of esophageal cancers. Our thorough, unbiased analysis provides a rich source of data for further studies into the molecular basis of tumorigenesis of the esophagus, as well as identification of potential biomarkers for early detection of progression.

Risk factors for Barrett’s oesophagus and oesophageal adenocarcinoma: Results from the FINBAR study

AIM: To investigate risk factors associated with Barrett’s oesophagus and oesophageal adenocarcinoma.

METHODS: This all-Ireland population-based case-control study recruited 224 Barrett’s oesophagus patients, 227 oesophageal adenocarcinoma patients and 260 controls. All participants underwent a structured interview with information obtained about potential lifestyle and environmental risk factors.

RESULTS: Gastro-oesophageal reflux was associated with Barrett’s [OR 12.0 (95% CI 7.64-18.7)] and oesophageal adenocarcinoma [OR 3.48 (95% CI 2.25-5.41)]. Oesophageal adenocarcinoma patients were more likely than controls to be ex- or current smokers [OR 1.72 (95% CI 1.06-2.81) and OR 4.84 (95% CI 2.72-8.61) respectively] and to have a high body mass index [OR 2.69 (95% CI 1.62-4.46)]. No significant associations were observed between these risk factors and Barrett's oesophagus. Fruit but not vegetables were negatively associated with oesophageal adenocarcinoma [OR 0.50 (95% CI 0.30-0.86)].

CONCLUSION: A high body mass index, a diet low in fruit and cigarette smoking may be involved in the progression from Barrett’s oesophagus to oesophageal adenocarcinoma.

Does Barrett's oesophagus develop over time in patients with chronic gastro-oesophageal reflux disease?

BACKGROUND

Barrett's oesophagus is present in 8-10% of patients with gastro-oesophageal reflux disease (GERD).

AIM

We performed a cohort study to determine the incidence of Barrett's oesophagus in patients with chronic heartburn symptoms.

METHODS

We identified patients, with GERD and/or Barrett's oesophagus between 1998 and 2004 by primary or secondary International Classification of Diseases (ICD-9) codes of 530.81 and/or 530.2, who had two or more oesophagogastroduodenoscopies performed at least 6 months apart.

RESULTS

We screened 11 040 patients (41 390 random data entries by ICD-9 code) and enrolled 515 (4.6%) GERD patients and 169 (1.5%) Barrett's oesophagus patients. The mean (+/-s.d.) number of oesophagogastroduodenoscopies in the GERD cohort was 3.2 +/- 1.8 (range: 2-15) over 3.4 +/- 2.2 (range: 0.5-11) years. None of the 412 (80%) GERD patients with non-erosive disease developed Barrett's oesophagus over a mean follow-up time of 3.4 +/- 2.2 years (95% CI: 0-0.9%). Five (1%) of the 103 GERD patients with erosive oesophagitis developed subsequent Barrett's oesophagus. Fifty-seven per cent of the GERD patients were on PPI therapy at the time of index endoscopy. None of the 169 Barrett's oesophagus patients had normal index oesophagogastroduodenoscopies within a mean retrospective time period of 4.5 +/- 2.8 years (95% CI: 0-2%). Using the ICD-9 code of 530.2 as a predictor of the presence of Barrett's oesophagus, the sensitivity was 79% with a specificity of 88%.

CONCLUSION

The majority of patients with GERD do not appear to develop Barrett's oesophagus when it is not present on the index endoscopy.

Gastroesophageal reflux symptoms in patients with adenocarcinoma of the esophagus or cardia

BACKGROUND

The efficacy of endoscopic screening for chronic gastroesophageal reflux symptoms of heartburn and regurgitation in adult subjects depends on the sensitivity of this strategy for detecting Barrett esophagus in subjects before the development of adenocarcinoma of the esophagus or cardia. The aim of the current study was to determine what proportion of patients with cancer of the esophagus or cardia would have been candidates for a screening endoscopy before their cancer diagnosis based on the presence and duration of preceding reflux symptoms.

METHODS

All patients with adenocarcinoma of the esophagus, adenocarcinoma of the cardia, or long-segment Barrett esophagus presenting for endoscopy at 4 tertiary care and 2 Veterans Affairs (VA) hospitals were given a previously validated questionnaire to determine their recall of common gastroesophageal reflux symptoms.

RESULTS

The study population of 375 subjects consisted primarily of 294 (78%) white men. Only 67 of 110 patients (61%) with adenocarcinoma of the esophagus and 8 of 21 patients (38%) with adenocarcinoma of the cardia recalled symptoms of heartburn or regurgitation being present for >5 years before their diagnosis of cancer. Only 40 of 110 patients (36%) with adenocarcinoma of the esophagus and 5 of 21 patients (24%) with adenocarcinoma of the cardia recalled weekly symptoms being present for >5 years before their cancer diagnosis. Of the 244 patients with Barrett esophagus, 170 (70%) recalled heartburn or regurgitation for >5 years and 89 patients (37%) recalled weekly symptoms for >5 years.

CONCLUSIONS

Current practice, which uses a screening strategy of performing endoscopy in patients with >5 years of heartburn or regurgitation, can detect Barrett epithelium in only a limited proportion of those patients at risk for developing adenocarcinoma of the esophagus or adenocarcinoma of the cardia.

Expression of calcium-binding proteins S100A2 and S100A4 in Barrett's adenocarcinomas

In this study, we investigated the mRNA and protein expression of S100A2 and S100A4 in adenocarcinomas of the stomach and esophagus. Real-time reverse transcription-polymerase reaction analysis on 72 tumors revealed frequent overexpression of S100A2 and S100A4 in Barrett's adenocarcinomas (BAs) (P < .01). Immunohistochemical analysis on tumor tissue microarrays that contained 187 tumors showed absent to weak staining for S100A2 in all normal gastric mucosa samples, whereas normal esophageal mucosa samples demonstrated moderate to strong nuclear staining. Contrary to the nuclear expression of S100A2 in normal esophageal mucosa, two thirds of Barrett's dysplasia and BAs that overexpressed S100A2 demonstrated stronger cytosolic staining than nuclear staining (P < .001). Overexpression of S100A2 protein was more frequently seen in well-differentiated tumors than in others (P = .02). Moderate to strong staining of S100A4 was detected in two thirds of tumors and was frequently observed in the presence of Barrett's esophagus (P = .02). Similar to S100A2, the expression of S100A4 was predominantly cytosolic in two thirds of the tumors (P = .001). There was a significant correlation between S100A4 overexpression and lymph node metastasis (N(2)-N(4)) (P = .027). These results demonstrate frequent cytosolic overexpression of S100A2 and S100A4 in BAs. Further studies are ongoing to understand the biological significance of these S100A proteins in Barrett's tumorigenesis.

Comparison of methylene blue-directed biopsies and four-quadrant biopsies in the detection of high-grade intraepithelial neoplasia and early cancer in Barrett's oesophagus

BACKGROUND

Barrett's oesophagus embodies the risk of malignant transformation. High-grade intraepithelial neoplasia and early cancer in Barrett's oesophagus are often discrete or macroscopically occult lesions and show a patchy distribution and therefore, directed biopsies in combination with four-quadrant random biopsies are the gold standard for surveillance.

AIMS

The aim of this prospective study was to compare methylene blue staining and random biopsies in patients with early Barrett's neoplasia.

PATIENTS AND METHODS

Eighty-six patients (mean age 65+/-8 years) with histologically proven but macroscopically in evident high-grade intraepithelial neoplasia (n=17) or early cancer in Barrett's oesophagus (n=69) on HR-endoscopy with all together 98 lesions, were included. In the first step, four-quadrant random biopsies were taken during routine endoscopy (group I). In a second step, staining was performed with a 0.5% solution of methylene blue with a spray catheter. Biopsies of focal areas with decreased stain, heterogeneity of stain or absence stain were taken (group II).

RESULTS

In 75/86 patients, high-grade intraepithelial neoplasia or early cancer in Barrett's oesophagus could be diagnosed in the methylene blue group while 56 patients were determined in the random biopsies group (P=0.053). High-grade intraepithelial neoplasia or early cancer was diagnosed in significantly more methylene blue-directed biopsies (80.9% versus 26.4%, P<0.005) and also significantly more lesions could be identified in the methylene blue group (96/98; 98%) while in the random biopsies group only 58/98 lesions (59%) could be localised (P<0.05). When methylene blue was used (1217 versus 562, P<0.0001), the average number of specimens taken with methylene blue per patient was about half of that with random biopsy (6.5 versus 14.1, P<0.0001).

CONCLUSIONS

Chromoendoscopy with methylene blue diagnosed significantly more patients and lesions with intraepithelial neoplasia or early cancer in Barrett's oesophagus compared to random biopsies. In addition, significantly less biopsies were needed with methylene blue compared to random biopsies. The use of methylene blue-directed biopsies appears to improve the detection of intraepithelial neoplasia and early cancer in Barrett's oesophagus.

Management of gastroesophageal reflux disease

Gastroesophageal reflux disease is the most common and expensive digestive disease with complex and multi-factorial pathophysiologic mechanisms. Transient inappropriate relaxation of the lower esophageal sphincter is the predominant mechanism in the majority of patients with mild to moderate disease. Hiatal hernias and a reduced lower esophageal sphincter pressure have a significant role in patients with moderate to severe disease. Typical manifestations of gastroesophageal reflux disease include heartburn, regurgitation, and dysphagia. Atypical symptoms, such as noncardiac chest pain, pulmonary manifestations of asthma, cough, aspiration pneumonia, or ENT manifestations of globus and laryngitis, can be seen in patients with or without typical symptoms of gastroesophageal reflux disease. Endoscopy and ambulatory pH tests are best to evaluate the anatomic and physiologic impact ofgastroesophageal reflux disease. Complications of chronic gastroesophageal reflux disease include peptic strictures and Barrett metaplasia. Barrett esophagus is a major risk factor for esophageal adenocarcinoma, and upper endoscopy with surveillance biopsies is recommended for patients with Barrett esophagus. Medical therapy with anti-secretory agents (H2 blockers and proton pump inhibitors) is effective for most patients with gastroesophageal reflux disease. Surgical fundoplications and endoscopic treatment modalities are mechanical treatment options for patients with gastroesophageal reflux disease.

Risk factors for the development of esophageal adenocarcinoma in Barrett's esophagus

OBJECTIVE

To identify risk factors for esophageal adenocarcinoma (EAC) in patients with Barrett's esophagus (BE).

METHODS

A hospital-based case-control study was performed in which 91 cases with EAC and 244 controls with histologically confirmed BE (>2 cm) with no dysplasia or low-grade dysplasia were included. Information on demographic, anthropometric, and lifestyle characteristics, physical activity levels, working posture, family history, gastroesophageal reflux disease (GERD) symptoms, and medication use was collected by questionnaire.

RESULTS

Cases more often were current smokers (odds ratio 3.7, 95% confidence interval 1.4-9.9), more often had a body mass index >25 assessed at age 20 (2.6, 1.2-5.5), and more frequently had been working in a stooped posture at age 20 (2.0, 1.1-3.9), compared to controls. In addition, cases less often experienced symptoms of heartburn (0.3, 0.2-0.5) and less frequently used proton pump inhibitors (0.1, 0.05-0.2), compared to controls, whereas use of nonsteroidal anti-inflammatory drugs/aspirin was more common among cases (1.8, 1.1-3.2). Cases more often were men, compared to controls (91%vs 67%, p < 0.001).

CONCLUSION

In patients with BE, the risk of EAC is related to risk factors for GERD, which is, however, asymptomatic. As these risk factors are common in Western countries, they are probably not helpful in individualization of surveillance intervals.

Difference of gene expression profiles between Barrett’s esophagus and cardia intestinal metaplasia by gene chip

The difference of gene expression profile changes in Barrett's esophagus (BE) and cardia intestinal metaplasia (CIM) epithelium was studied and the novel associated genes were screened in the early stage by cDNA microarray. The cDNA retro-transcribed from equal quantity mRNA from BE and CIM epithelial tissues were labeled with Cy3 and Cy5 fluorescence as probes. The mixed probe was hybridized with three pieces BiostarH-40s double dot human whole gene chip. The chips were scanned with a ScanArray 4000. The acquired images were analyzed using GenePix Pro 3.0 software. It was found a total of 141 genes were screened out that exhibited differentially expression more than 2 times in all three chips. It was identified that in gene expression profiles of BE, 74 genes were up-regulated and 67 down-regulated as compared with CIM. The comparison between the difference of gene expression profile changes in BE and CIM epithelia revealed that there existed the difference between BE and CIM at gene level. 141 genes with the expression more than two time were probably related to the occurrence and development of BE and the promotion or progress in adenocarcinoma.

Hypermethylation and loss of expression of glutathione peroxidase-3 in Barrett's tumorigenesis

Chronic gastroesophageal reflux disease is a known risk factor for Barrett's esophagus (BE), which induces oxidative mucosal damage. Glutathione peroxidase-3 (GPx3) is a secretory protein with potent extracellular antioxidant activity. In this study, we have investigated the mRNA and protein expression of GPx3, and explored promoter hypermethylation as an epigenetic mechanism for GPx3 gene inactivation during Barrett's carcinogenesis. Quantitative real-time reverse transcription polymerase chain reaction on 42 Barrett's adenocarcinomas (BAs) revealed consistently reduced levels of GPx3 mRNA in 91% of tumor samples. GPx3 promoter hypermethylation was detected in 62% of Barrett's metaplasia, 82% of dysplasia, and 88% of BA samples. Hypermethylation of both alleles of GPx3 was most frequently seen in BAs (P = .001). Immunohistochemical staining of GPx3 in matching tissue sections (normal, BE, Barrett's dysplasia, and BA) revealed strong immunostaining for GPx3 in normal esophageal and gastric tissues. However, weak to absent GPx3 staining was observed in Barrett's dysplasia and adenocarcinoma samples where the promoter was hypermethylated. The degree of loss of immunohistochemistry correlated with the hypermethylation pattern (monoallelic versus biallelic). The observed high frequency of promoter hypermethylation and progressive loss of GPx3 expression in BA and its associated lesions, together with its known function as a potent antioxidant, suggest that epigenetic inactivation and regulation of glutathione pathway may be critical in the development and progression of BE.

Barrett's Metaplasia: defining the problem

Concern over how best to manage individuals with Barrett's esophagus (BE) has grown because of the consistent rise in the incidence of esophageal adenocarcinoma. Since the 1970s, the rate of increase in incidence of esophageal adenocarcinoma has been greater than that for any other cancer in the US population. Patients with BE have increased risk for esophageal cancer, but the rate of progression and potential risk factors in progression remain poorly understood. Much remains to be learned about BE and its association with adenocarcinoma before effective surveillance or management strategies can be defined and implemented. In this article, the relationship between BE and gastroesophageal reflux disease, risk for adenocarcinoma, and prospects for molecular diagnosis are discussed.

Spectroscopy and fluorescence in esophageal diseases

Malignant tumors of the esophagus continue to be a major health issue associated with high mortality primarily because most present with symptoms of dysphagia or anaemia. The disease at that stage is advanced and not likely curable. The big issue for squamous dysplasia and that associated with BE is that only a small proportion are discovered in surveillance programs when they are asymptomatic, either because the patient lives in a high-incidence geographical area, has a family history, previously diagnosed head and neck cancer or chronic reflux, as in Barrett's. Current endoscopic methods are hampered by the endoscopist's inability to recognize subtle topographic clues of dysplasia, sampling errors related to biopsy protocols, and confounding inflammation-induced artifacts both for the endoscopist and pathologist. What is desperately needed would be a biomarker (e.g. serological, fecal, urinary) that selects patients for endoscopy. However, such a test is not yet on the horizon. This article examines the current status in practice and research of novel optically based 'bioendoscopic' devices (i.e. fluorescence spectroscopy and imaging, confocal fluorescence microendoscopy (CFM), light scattering spectroscopy (LSS), Raman spectroscopy (RS), and immunophotodiagnostic endoscopy) which may enhance the diagnosis of dysplasia in all patients undergoing conventional white light endoscopy. Perhaps these new technologies will lead to more cost-effective diagnosis, mapping (e.g. surface), and staging (e.g. depth) of dysplasia, thereby allowing timely cure by endoscopic means (e.g. EMR and/or PDT), biological interventions (e.g. Cox-2 inhibitors) rather than esophajectomy.

Primary care physician attitudes toward endoscopic screening for GERD symptoms and unsedated esophagoscopy

BACKGROUND

Current guidelines recommend consideration of screening patients with chronic GERD for Barrett's esophagus (BE). Unsedated esophagoscopy (UE) is a less costly alternative to standard EGD for identifying BE. The aim of this study was to determine the indications for EGD referral, the barriers to screening, and the interest in performing UE.

METHODS

A one-page survey was mailed to a random sample of 500 family practitioners and 500 internists. This sample was obtained from the American Academy of Family Physicians and American Society of Internal Medicine (500 from each organization).

RESULTS

The overall response rate was 54%. The majority (78%) refer more than 50% of their GERD patients for EGD; however, 34% also refer more than 10% of their patients for barium studies. Primary care physicians cited alarm symptoms, refractory symptoms, and chronicity and severity of symptoms as the major indications for referral for EGD. Gender, age, obesity, and tobacco use were cited less frequently. Cost of endoscopy, poor patient acceptance, and lack of evidence were the most common reasons cited for not referring for EGD. A majority of respondents (62%) indicated that the availability of UE would increase referral for the procedure, and 52% would be willing to perform UE in their office.

CONCLUSIONS

Severe, refractory, and chronic symptoms are the primary reasons for endoscopic referral from primary care physicians who manage patients with GERD. Other risk factors for BE, such as gender and age, do not appear to be important determinants for endoscopic referral. Further evaluation of UE as a mechanism to increase screening for BE in primary care patients is merited.

Endoprevention of esophageal cancer: endoscopic ablation of Barrett's metaplasia and dysplasia

This review describes the use of endoscopic therapy for the treatment of Barrett's disease and the prevention of esophageal carcinoma, predominantly a disease of older white men. While the term endoprevention may be novel, gastroenterologists have been using endoscopic techniques to prevent colon cancer for decades. For the endoprevention of Barrett's carcinoma, the regulatory approval for the use of porfimer sodium photodynamic therapy was an important milestone, as this treatment has been proven to safely ablate Barrett's glandular epithelium, including high-grade dysplasia, and significantly decrease the risk for the development of invasive cancer in several single-center studies, a prospective multicenter randomized controlled study using expert centralized histopathology analysis and long-term single-center results. Newer methods of mucosal ablation, such as the radiofrequency balloon, have been developed for the treatment of patients with Barrett's metaplasia or dysplasia. These newly developed techniques are able to treat large fields of glandular epithelium in a short treatment procedure using safe, effective, durable methods for the complete ablation of Barrett's metaplasia and low-grade dysplasia. These techniques may finally allow the interventional gastrointestinal endoscopist to prevent the development of esophageal carcinoma, just as colonoscopy with polypectomy has prevented colon cancer. However, it will be critically important to document the safety, durability and efficacy of these devices. Ultimately, the impact of successful Barrett's ablation on the incidence of Barrett's carcinoma, and the need for postablation surveillance endoscopy must be determined.

The rationale for screening and surveillance of Barrett's metaplasia

Oesophageal adenocarcinoma is a rare cancer; however, it is the most rapidly increasing cancer in the western world. Barrett's oesophagus is the only recognised precursor and is associated with the majority of cases of adenocarcinoma. The role of screening and surveillance in patients with Barrett's oesophagus remains controversial. There is insufficient evidence to show that screening improves survival and is cost-effective. Indirect evidence suggests that patients diagnosed with cancer while undergoing surveillance endoscopy are diagnosed at an earlier stage and have an improved survival. The problems with current surveillance techniques include lack of data on natural history of Barrett's oesophagus, test invasiveness, costs, lack of standardisation and validation of biopsy and treatment protocols, and endoscopy intervals. The use of novel endoscopic techniques and biomarkers combined with better identification of high-risk groups could make screening and surveillance a cost-effective practice in the future.

Barrett's esophagus is common in older men and women undergoing screening colonoscopy regardless of reflux symptoms

BACKGROUND

Although Barrett's esophagus (BE) is the precursor of esophageal adenocarcinoma (ACA), most patients with ACA present outside of a BE surveillance program. This could be due to undiagnosed symptomatic GER and BE or BE/ACA occurring in patients without reflux symptoms. We have, therefore, studied the prevalence of BE and symptom status in older patients referred for colonoscopy.

METHODS

All patients referred for outpatient colonoscopy were eligible if they were at least 65 yr old and had not previously undergone esophagoscopy. After informed consent, the patients completed detailed GER questionnaires. During the research endoscopy, the endoscopist recorded the squamocolumnar junction (SCJ) as either long-segment BE (LSBE), short-segment BE (SSBE), or normal. If the SCJ was felt to be "irregular" the endoscopist was asked to predict, in their judgment, if BE was present. All patients had biopsies below the SCJ, which were examined by a gastrointestinal pathologist who was blinded to the endoscopic findings.

RESULTS

BE esophagus was present in 50 of the 300 patients studied (16.7%). BE was more common in men (35 of 161, 21.7%) than in women (15 of 139, 10.8%) (p < 0.025). GERD symptoms were reported in 106 patients (35%) and BE was present in 19.8% of symptomatic and 14.9% of asymptomatic cases (NS). The majority of the BE in this study was less than 3 cm in length (92%). The questionnaires did not predict the presence of BE.

CONCLUSIONS

BE is common in unscreened male and female patients at least 65 yr of age who are referred for colonoscopy. Men were more likely than women to have BE although it occurred in both sexes. Reflux symptoms were fairly common but a poor predictor of BE.

Photodynamic therapy for Barrett's esophagus with high-grade dysplasia

This article describes advances in photodynamic therapy for patients with Barrett's esophagus and high-grade dysplasia-an important, minimally invasive treatment option proven to safely and durably ablate Barrett's dysplasia and prevent carcinoma while preserving the gastroesophageal junction.

The molecular signature of normal squamous esophageal epithelium identifies the presence of a field effect and can discriminate between patients with Barrett's esophagus and patients with Barrett's-associated adenocarcinoma

BACKGROUND AND AIM

Genetic alterations in the normal tissues surrounding various cancers have been described, but a comprehensive analysis of this carcinogenic field effect in Barrett's-associated adenocarcinoma of the esophagus disease has not been reported. The aim of this study was to analyze the gene expression profile of a panel of highly selected genes in the normal squamous esophagus epihelium of patients with Barrett's esophagus, patients with Barrett's-associated adenocarcinoma, and a healthy control group to define the existence of a carcinogenic field effect, and to investigate the clinical importance of such a field effect in the management of Barrett's disease.

METHODS

Forty-nine histologic normal squamous esophageal epithelia collected from 19 patients with Barrett's esophagus, 20 patients with Barrett's-associated esophageal adenocarcinoma, and a healthy control group of 10 patients were studied. A quantitative real-time reverse transcription-PCR method (TaqMan) was used to measure the expression of a panel of genes with known associations with gastrointestinal carcinogenesis.

RESULTS

A widespread carcinogenic field effect was detected for more than 50% of the genes analyzed including Bax, BFT, CDX2, COX2, DAPK, DNMT1, GSTP1, RARalpha, RARgamma, RXRalpha, RXRbeta, SPARC, TSPAN, and VEGF. Based on the expression signature of the normal appearing squamous esophagus, a linear discriminant analysis was able to distinguish between the three groups of patients with an error rate of 0%.

CONCLUSION

This study provides the first comprehensive investigation of a carcinogenic field effect in Barrett's esophagus disease. Based on the gene expression signature of the normal esophagus, patients could be correctly characterized according to their pathologic classification by applying a linear discriminant analysis. Our results provide evidence that a molecular classification might have clinical importance for the diagnosis and treatment of patients with Barrett's esophagus disease.

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.

The changing epidemiology of esophageal cancer in Finland and the impact of the surveillance of Barrett's esophagus in detecting esophageal adenocarcinoma

We examined the epidemiology of esophageal cancer in Finland and the role of the surveillance of Barrett's esophagus (BE) in detecting esophageal adenocarcinoma (EA) in our own hospital referral area. We observed that the incidence of EA in men has increased tenfold from the 1970s and was 1.10/100,000/year in 1998-2002. In women, a 4.5-fold increase was observed (incidence 0.11/100,000/year). In 1998-2002, the mean annual number of new EA cases was 57.4 (79.8% men) in Finland with a population of 5.2 million. In our hospital referral area with a mean population of 261 349, 11 EAs were observed in 1996-2001. Of them, two (18.2%) had BE. One EA was detected during surveillance. EA comprised 0.05% of all causes of deaths in our hospital referral area. We conclude that EA incidence has increased significantly in men in Finland, but still EA is seldom detected on BE surveillance. EA is an uncommon cause of death in our hospital referral area.

Molecular biology of esophageal cancer in the genomics era

The incidence of esophageal adenocarcinoma is rising in the United States and Western countries. Significant differences exist between esophageal adenocarcinoma and squamous cell carcinoma in the molecular mechanisms responsible for the tumorigenesis process. State-of-the-art techniques such as gene microarrays and proteomics will greatly aid in the development of new therapies targeting specific molecular pathways,ultimately leading to improved survival in patients who have esophageal cancer.

Does screening for Barrett's esophagus and adenocarcinoma of the esophagus prolong survival?

Despite the paucity of data supporting its use, screening upper endoscopy for patients with chronic gastroesophageal reflux disease symptoms to assess for Barrett's esophagus and esophageal adenocarcinoma has become a widely accepted practice. We apply the principles of screening to Barrett's esophagus and esophageal adenocarcinoma. Critical application of the key criteria of screening to this situation demonstrates that several criteria are unfulfilled. Key data are not available with which to judge other criteria. The major fault with screening for Barrett's esophagus is that the at-risk population is too broadly characterized and that too many cancers occur outside of this risk pool. Thus, recommendations for screening cannot be endorsed. Efforts may be better directed at further research identifying groups at risk for esophageal adenocarcinoma, developing more accurate and less-invasive methods of diagnosis, and discovering the underlying factors which continue to drive the increased incidence of this disease.

Frequent methylation of eyes absent 4 gene in Barrett's esophagus and esophageal adenocarcinoma

Most esophageal adenocarcinomas arise within Barrett's esophagus but the cause of this increasingly prevalent condition remains unknown. Early detection improves survival and discriminant screening markers for Barrett's esophagus and cancer are needed. This study was designed to explore the natural history of eyes absent 4 (EYA4) gene methylation in the neoplastic progression of Barrett's esophagus and to evaluate methylated EYA4 as a candidate marker. Aberrant promoter methylation of EYA4 was studied by methylation-specific PCR using bisulfite-treated DNA from esophageal adenocarcinomas, Barrett's esophagus, and normal epithelia, and then confirmed by sequencing. Eight cancer cell lines were treated with the demethylation agent 5-aza-2'-deoxycytidine, and EYA4 mRNA expression with and without treatment was quantified by real-time reverse-transcription PCR. EYA4 hypermethylation was detected in 83% (33 of 40) of esophageal adenocarcinomas and 77% (27 of 35) of Barrett's tissues, but only in 3% (2 of 58) of normal esophageal and gastric mucosa samples (P < 0.001). The unmethylated cancer cell lines had much higher EYA4 mRNA expression than the methylated cancer cell lines. Demethylation caused by 5-aza-2'-deoxycytidine increased the mRNA expression level by a median of 3.2-fold in methylated cells, but its effect on unmethylated cells was negligible. Results indicate that aberrant promoter methylation of EYA4 is very common during tumorigenesis in Barrett's esophagus, occurs in early metaplasia, seems to be an important mechanism of down-regulating EYA4 expression, and represents an intriguing candidate marker for Barrett's metaplasia and esophageal cancer.

Molecular targets for treatment of Barrett's esophagus

SUMMARY. Esophageal cancer is one of the most deadly forms of gastrointestinal cancer with a mortality rate exceeding 90%. The major risk factors for esophageal adenocarcinoma are gastroesophageal reflux disease (GERD) and its sequela, Barrett's esophagus. GERD commonly leads to esophagitis. In a minority of patients however, ongoing GERD leads to replacement of esophageal squamous mucosa with metaplastic, intestinal-type Barrett's mucosa. In the setting of continued peptic injury, Barrett's mucosa can give rise to esophageal adenocarcinoma. Despite the widespread use of potent acid suppressive therapies for patients with GERD, the incidence of esophageal adenocarcinoma, among white men in the USA, the UK and Europe has continued to rise. Cancers in Barrett's esophagus arise through a sequence of genetic events that endow the cells with six essential physiologic hallmarks of cancer as described by Hanahan and Weinberg in 2000. These cancer hallmarks include the ability to proliferate without exogenous stimulation, to resist growth-inhibitory signals, to avoid triggering the programmed death mechanism (apoptosis), to resist cell senescence, to develop new vascular supplies (angiogenesis), and to invade and metastasize. While the acquisition of these essential attributes is not specific to the neoplastic progression of Barrett's esophagus, this review will focus on the genetic alterations that occur in Barrett's cells that contribute to the acquisition of each of the hallmarks. Moreover, potential diagnostic and therapeutic strategies for Barrett's patients aimed at each of these cancer hallmarks will be reviewed.

Dysplasia and risk of further neoplastic progression in a regional Veterans Administration Barrett's cohort

OBJECTIVES

No published data are available on the risk of further neoplastic progression in Barrett's patients stratified by baseline dysplasia status. Our aims were to estimate and compare the risk of progression to high-grade dysplasia or cancer in groups of Barrett's patients stratified by baseline dysplasia status.

METHODS

Consecutive Barrett's cases from 1988-2002 were identified via pathology databases in a regional VA health-care system and medical record data were abstracted. The risk of progression to high-grade dysplasia or cancer was measured and compared in cases with versus without low-grade dysplasia within 1 yr of index endoscopy using survival analysis.

RESULTS

A total of 575 Barrett's cases had 2,775 patient-years of follow-up. There were 13 incident cases of high-grade dysplasia and two of cancer. The crude rate of high-grade dysplasia or cancer was 1 of 78 patient-years for those with baseline dysplasia versus 1 of 278 patient-years for those without (p= 0.001). One case of high-grade dysplasia in each group underwent successful therapy. One incident cancer case underwent successful resection and the other was unresectable. Two cases with high-grade dysplasia later developed cancer, one died postoperatively, the other was unresectable. When these two cases were included (total of four cancers), the crude rate of cancer was 1 of 274 patient-years for those with baseline dysplasia versus 1 of 1,114 patient-years for those without.

CONCLUSIONS

In a large cohort study of Barrett's, incident malignancy was uncommon. The rate of progression to high-grade dysplasia or cancer was significantly higher in those with baseline low-grade dysplasia. These data may warrant reevaluation of current Barrett's surveillance strategies.

Surveillance and screening for Barrett esophagus and adenocarcinoma

Current recommendations for screening and surveillance of Barrett esophagus and related lesions are based on recent guidelines by the Practice Parameters Committee of the American College of Gastroenterology. The purpose of this review is to critically examine the rationale and evidence behind these recommendations. There is strong rationale for vigorous initial testing to document the baseline status and identify early adenocarcinoma, and for surveillance of high-grade dysplasia. Recommendations for esophagectomy in patients with high-grade dysplasia need to be individualized. However, recommendations for surveillance of low-grade dysplasia and specialized intestinal metaplasia without dysplasia are largely opinion statements not well supported by objective data. Although cancers identified by surveillance are at earlier stages than those diagnosed without prior endoscopic evaluation, surveillance failures are common. Recommendations for screening and surveillance are not evidence-based and unlikely to alter national mortality from esophageal adenocarcinoma. Their impact on individual patients depends on individual circumstances. Current recommendations are limited by inconsistent endoscopic findings and sampling errors, inconsistent histologic diagnoses of Barrett esophagus and dysplasia, and our poor understanding of the natural history of various histologic lesions. Future directions include validation of methods that reduce these inconsistencies by in vivo detection of abnormalities and by objective diagnostic markers besides grades of dysplasia, such DNA content analysis and molecular markers, and improved understanding of the disease progression. Effective screening programs depend on development of simple, inexpensive, and reliable methods to identify the small group of patients truly at high risk for adenocarcinoma for endoscopic screening.