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

Ductal metaplasia in oesophageal submucosal glands is associated with inflammation and oesophageal adenocarcinoma

AIMS

Recent studies have suggested that oesophageal submucosal gland (ESMG) ducts harbour progenitor cells that may contribute to oesophageal metaplasia. Our objective was to determine whether histological differences exist between the ESMGs of individuals with and without oesophageal adenocarcinoma (EAC).

METHODS AND RESULTS

We performed histological assessment of 343 unique ESMGs from 30 control patients, 24 patients with treatment-naïve high-grade columnar dysplasia (HGD) or EAC, and 23 non-EAC oesophagectomy cases. A gastrointestinal pathologist assessed haematoxylin and eosin-stained ESMG images by using a scoring system that assigns individual ESMG acini to five histological types (mucous, serous, oncocytic, dilated, or ductal metaplastic). In our model, ductal metaplastic acini were more common in patients with HGD/EAC (12.7%) than in controls (3.5%) (P = 0.006). We also identified greater proportions of acini with dilation (21.9%, P < 0.001) and, to a lesser extent, ductal metaplasia (4.3%, P = 0.001) in non-EAC oesophagectomy cases than in controls. Ductal metaplasia tended to occur in areas of mucosal ulceration or tumour.

CONCLUSIONS

We found a clear association between ductal metaplastic ESMG acini and HGD/EAC. Non-EAC cases had dilated acini and some ductal dilation. Because ESMGs and ducts harbour putative progenitor cells, these associations could have significance for understanding the pathogenesis of EAC.

Screening for Barrett's Esophagus

The large increase in the incidence of esophageal adenocarcinoma in the West during the past 30 years has stimulated interest in screening for Barrett's esophagus (BE), a precursor to esophageal cancer. Effective endoscopic treatments for dysplasia and intramucosal cancer, coupled with screening programs to detect BE, could help reverse the increase in the incidence of esophageal cancer. However, there are no accurate, cost-effective, minimally invasive techniques available to screen for BE, reducing the enthusiasm of gastroenterologists. Over the past 5 years, there has been significant progress in the development of screening technologies. We review existing and developing technologies, new minimally invasive imaging techniques, nonendoscopic devices for cell collection, and biomarkers that can be measured in blood or stool samples. We discuss the status of these approaches, data from clinical studies of their effects, and their anticipated strengths and weaknesses in screening. The area is rapidly evolving, and new tools will soon be ready for prime time.

Screening for Barrett's esophagus and esophageal adenocarcinoma: rationale, recent progress, challenges, and future directions

As the incidence and mortality of esophageal adenocarcinoma continue to increase, strategies to counter this need to be explored. Screening for Barrett's esophagus, which is the known precursor of a large majority of adenocarcinomas, has been debated without a firm consensus. Given evidence for and against perceived benefits of screening, the multitude of challenges in the implementation of such a strategy and in the downstream management of subjects with Barrett's esophagus who could be diagnosed by screening, support for screening has been modest. Recent advances in the form of development and initial accuracy of noninvasive tools for screening, risk assessment tools, and biomarker panels to risk stratify subjects with BE, have spurred renewed interest in the early detection of Barrett's esophagus and related neoplasia, particularly with the advent of effective endoscopic therapy. In this review, we explore in depth the potential rationale for screening for Barrett's esophagus, recent advances that have the potential of making screening feasible, and also highlight some of the challenges that will have to be overcome to develop an effective approach to improve the outcomes of subjects with esophageal adenocarcinoma.

MIC-1/GDF15 in Barrett's oesophagus and oesophageal adenocarcinoma

Background:

Biomarkers are needed to improve current diagnosis and surveillance strategies for patients with Barrett's oesophagus (BO) and oesophageal adenocarcinoma (OAC). Macrophage inhibitory cytokine 1/growth differentiation factor 15 (MIC-1/GDF15) tissue and plasma levels have been shown to predict disease progression in other cancer types and was therefore evaluated in BO/OAC.

Methods:

One hundred thirty-eight patients were studied: 45 normal oesophagus (NE), 37 BO, 16 BO with low-grade dysplasia (LGD) and 40 OAC.

Results:

Median tissue expression of MIC-1/GDF15 mRNA was ⩾25-fold higher in BO and LGD compared to NE (P<0.001); two-fold higher in OAC vs BO (P=0.039); and 47-fold higher in OAC vs NE (P<0.001). Relative MIC-1/GDF15 tissue expression >720 discriminated between the presence of either OAC or LGD vs NE with 94% sensitivity and 71% specificity (ROC AUC 0.86, 95% CI 0.73–0.96; P<0.001). Macrophage inhibitory cytokine 1/growth differentiation factor 15 plasma values were also elevated in patients with OAC vs NE (P<0.001) or BO (P=0.015).

High MIC-1/GDF15 plasma levels (⩾1140 pg ml⁻¹) were an independent predictor of poor survival for patients with OAC (HR 3.87, 95% CI 1.01–14.75; P=0.047).

Conclusions:

Plasma and tissue levels of MIC-1/GDF15 are significantly elevated in patients with BO, LGD and OAC. Plasma MIC-1/GDF15 may have value in diagnosis and monitoring of Barrett's disease.

Risk factors and populations at risk: selection of patients for screening for Barrett's oesophagus

Screening for Barrett's oesophagus is an attractive notion due to the rising incidence of oesophageal adenocarcinoma, the relative ease of acquiring tissue from the oesophagus, and the availability of endoscopic therapy for early neoplastic lesions. If screening is recommended, the question remains: which patients should be screened? Endoscopy is frequently performed in patients with symptoms of gastro-oesophageal reflux disease, but the vast majority of patients diagnosed with oesophageal adenocarcinoma have never undergone a prior endoscopy. The efficiency of screening needs to be improved. A number of tools for predicting the presence of Barrett's oesophagus or future risk of developing oesophageal adenocarcinoma are available. More research is needed to validate these tools and to identify the thresholds at which screening should be offered.

A randomized comparative effectiveness trial of novel endoscopic techniques and approaches for Barrett's esophagus screening in the community

OBJECTIVES

The objective of this study was to compare participation rates and clinical effectiveness of sedated esophagogastroduodenoscopy (sEGD) and unsedated transnasal endoscopy (uTNE) for esophageal assessment and Barrett's esophagus (BE) screening in a population-based cohort.

METHODS

This was a prospective, randomized, controlled trial in a community population. Subjects ≥50 years of age who previously completed validated gastrointestinal symptom questionnaires were randomized (stratified by age, sex, and reflux symptoms) to one of three screening techniques (either sEGD or uTNE in a mobile research van (muTNE) or uTNE in a hospital outpatient endoscopy suite (huTNE)) and invited to participate.

RESULTS

Of the 459 subjects, 209 (46%) agreed to participate (muTNE n=76, huTNE n=72, and sEGD n=61). Participation rates were numerically higher in the unsedated arms of muTNE (47.5%) and huTNE (45.7%) compared with the sEGD arm (40.7%), but were not statistically different (P=0.27). Complete evaluation of the esophagus was similar using muTNE (99%), huTNE (96%), and sEGD (100%) techniques (P=0.08). Mean recovery times (min) were longer for sEGD (67.3) compared with muTNE (15.5) and huTNE (18.5) (P<0.001). Approximately 80% of uTNE subjects were willing to undergo the procedure again in future. Respectively, 29% and 7.8% of participating subjects had esophagitis and BE.

CONCLUSIONS

Mobile van and clinic uTNE screening had comparable clinical effectiveness with similar participation rates and safety profile to sEGD. Evaluation time with uTNE was significantly shorter. Prevalence of BE and esophagitis in community subjects ≥50 years of age was substantial. Mobile and outpatient unsedated techniques may provide an effective alternative strategy to sEGD for esophageal assessment and BE screening.

Comparative acceptability of transnasal esophagoscopy and esophageal capsule esophagoscopy: a randomized, controlled trial in veterans

BACKGROUND

EGD screening for Barrett's esophagus (BE) is costly, with insufficient evidence to support its effectiveness.

OBJECTIVE

To compare acceptance and tolerability of 2 novel, office-based, endoscopic screening techniques done on nonsedated patients.

DESIGN

Randomized block study design with allocation concealment.

SETTING

Outpatient clinic setting at a Veterans Affairs medical center.

PATIENTS

A total of 184 veterans with or without GERD symptoms.

INTERVENTIONS

Transnasal esophagoscopy (TNE) or esophageal capsule esophagoscopy (ECE).

MAIN OUTCOME MEASUREMENTS

Acceptance and tolerability of TNE and ECE and effectiveness of BE screening.

RESULTS

Esophageal screening was accepted by 184 of 1210 (15.2%) veterans. The majority were men (96%) and African American (58%), with a mean (± standard deviation) age of 58.9 (± 8.1) years. Five TNE participants (5%) and 2 ECE participants (2%) refused the assigned procedure after randomization (P = .25). Eleven patients (12.6%) randomized to TNE crossed the minimal clinically important threshold for overall procedure tolerability, as opposed to no patients randomized to ECE (P = .001). Effectiveness of BE screening was not significantly different in both procedures (TNE vs ECE = 3.2% vs 5.4%; P = .47). Overall, BE was present in 8 of 75 white participants (10.6%) and in 0 of 107 African American participants (P < .001).

LIMITATIONS

The general veteran population may not reflect the screening population for BE.

CONCLUSION

Despite a small proportion of veterans expressing interest in esophageal screening, both TNE and ECE were feasible in the outpatient clinic setting and were accepted by >95% of participants who did express an interest. Screening was effective only in white participants. Moderate differences in tolerability between TNE and ECE notwithstanding, cost considerations along with availability of equipment and trained personnel should guide the modality to be used for BE screening.

High Expression of Cathepsin E in Tissues but Not Blood of Patients with Barrett's Esophagus and Adenocarcinoma

Background

Cathepsin E (CTSE), an aspartic proteinase, is differentially expressed in the metaplasia–dysplasia–neoplasia sequence of gastric and colon cancer. We evaluated CTSE in Barrett’s esophagus (BE) and cancer because increased CTSE levels are linked to improved survival in several cancers, and other cathepsins are up-regulated in BE and esophageal adenocarcinoma (EAC).

Methods

A total of 273 pretreatment tissues from 199 patients were analyzed [31 normal squamous esophagus (NE), 29 BE intestinal metaplasia, 31 BE with dysplasia (BE/D), 108 EAC]. CTSE relative mRNA expression was measured by real-time polymerase chain reaction, and protein expression was measured by immunohistochemistry. CTSE serum levels were determined by enzyme-linked immunosorbent assay.

Results

Median CTSE mRNA expression levels were ≥1,000-fold higher in BE/intestinal metaplasia and BE/D compared to NE. CTSE levels were significantly lower in EAC compared to BE/intestinal metaplasia and BE/D, but significantly higher than NE levels. A similar expression pattern was present in immunohistochemistry, with absent staining in NE, intense staining in intestinal metaplasia and dysplasia, and less intense EAC staining. CTSE serum analysis did not discriminate patient groups. In a uni- and multivariable Cox proportional hazards model, CTSE expression was not significantly associated with survival in patients with EAC, although CTSE expression above the 25th percentile was associated with a 41 % relative risk reduction for death (hazard ratio 0.59, 95 % confidence interval 0.27–1.26, p = 0.17).

Conclusions

CTSE mRNA expression is up-regulated more than any known gene in Barrett intestinal metaplasia and dysplasia tissues. Protein expression is similarly highly intense in intestinal metaplasia and dysplasia tissues.

Electronic supplementary material

The online version of this article (doi:10.1245/s10434-014-4155-y) contains supplementary material, which is available to authorized users.

Controversies in Barrett esophagus

Barrett esophagus develops when metaplastic columnar epithelium predisposed to develop adenocarcinoma replaces esophageal squamous epithelium damaged by gastroesophageal reflux disease. Although several types of columnar metaplasia have been described in Barrett esophagus, intestinal metaplasia with goblet cells currently is required for a definitive diagnosis in the United States. Studies indicate that the risk of adenocarcinoma for patients with nondysplastic Barrett esophagus is only 0.12% to 0.38% per year, which is substantially lower than previous studies had suggested. Nevertheless, the incidence of esophageal adenocarcinoma continues to rise at an alarming rate. Regular endoscopic surveillance for dysplasia is the currently recommended cancer prevention strategy for Barrett esophagus, but a high-quality study has found no benefit of surveillance in preventing deaths from esophageal cancer. Medical societies currently recommend endoscopic screening for Barrett esophagus in patients with multiple risk factors for esophageal adenocarcinoma, including chronic gastroesophageal reflux disease, age of 50 years or older, male sex, white race, hiatal hernia, and intra-abdominal body fat distribution. However, because the goal of screening is to identify patients with Barrett esophagus who will benefit from endoscopic surveillance and because such surveillance may not be beneficial, the rationale for screening might be made on the basis of faulty assumptions. Endoscopic ablation of dysplastic Barrett metaplasia has been reported to prevent its progression to cancer, but the efficacy of endoscopic eradication of nondysplastic Barrett metaplasia as a cancer preventive procedure is highly questionable. This review discusses some of these controversies that affect the physicians and surgeons who treat patients with Barrett esophagus. Studies relevant to controversial issues in Barrett esophagus were identified using PubMed and relevant search terms, including Barrett esophagus, ablation, dysplasia, radiofrequency ablation, and endoscopic mucosal resection.

Esophageal cancer: A Review of epidemiology, pathogenesis, staging workup and treatment modalities

Esophageal cancer is a serious malignancy with regards to mortality and prognosis. It is a growing health concern that is expected to increase in incidence over the next 10 years. Squamous cell carcinoma is the most common histological type of esophageal cancer worldwide, with a higher incidence in developing nations. With the increased prevalence of gastroesophageal reflux disease and obesity in developed nations, the incidence of esophageal adenocarcinoma has dramatically increased in the past 40 years. Esophageal cancer is staged according to the widely accepted TNM system. Staging plays an integral part in guiding stage specific treatment protocols and has a great impact on overall survival. Common imaging modalities used in staging include computed tomography, endoscopic ultrasound and positron emission tomography scans. Current treatment options include multimodality therapy mainstays of current treatment include surgery, radiation and chemotherapy. Tumor markers of esophageal cancer are an advancing area of research that could potentially lead to earlier diagnosis as well as playing a part in assessing tumor response to therapy.

Development of a program to train physician extenders to perform transnasal esophagoscopy and screen for Barrett's esophagus

BACKGROUND & AIMS

Screening for Barrett's esophagus (BE) and esophageal adenocarcinoma is not recommended because it was not found to be cost effective. However, physician extenders (PEs) are able to perform unsedated procedures; their involvement might reduce the costs of BE screening. We examined the feasibility of training PEs to independently perform transnasal esophagoscopy (TNE) and screen patients for BE and measured their learning curve.

METHODS

Two PEs at a Veterans Affairs (VA) medical center underwent a structured didactic training program and observed nasopharyngoscopies before performing TNE under the supervision of attending endoscopists. Individual technical and cognitive components of TNE were rated on a 9-point structured scale. Learning curves were constructed using cumulative summation. Once the PEs were judged to be technically competent, each PE performed 10 independent videotaped TNEs, which were graded.

RESULTS

Both PEs identified anatomic landmarks after 18 consecutive procedures. PE1 and PE2 performed satisfactory nasal intubations after 20 and 25 procedures and esophageal intubations after 29 and 35 procedures, respectively. They acquired overall competence after supervised training on 43 and 47 procedures, respectively.

CONCLUSIONS

We developed a program at a VA medical center to train PEs to perform TNE to screen for BE. The PEs were able to perform TNE and recognize esophageal landmarks independently after a modest number of supervised procedures.

Gastro-esophageal reflux disease symptoms and demographic factors as a pre-screening tool for Barrett's esophagus

Background

Barrett’s esophagus (BE) occurs as consequence of reflux and is a risk factor for esophageal adenocarcinoma. The current “gold-standard” for diagnosing BE is endoscopy which remains prohibitively expensive and impractical as a population screening tool. We aimed to develop a pre-screening tool to aid decision making for diagnostic referrals.

Methodology/Principal Findings

A prospective (training) cohort of 1603 patients attending for endoscopy was used for identification of risk factors to develop a risk prediction model. Factors associated with BE in the univariate analysis were selected to develop prediction models that were validated in an independent, external cohort of 477 non-BE patients referred for endoscopy with symptoms of reflux or dyspepsia. Two prediction models were developed separately for columnar lined epithelium (CLE) of any length and using a stricter definition of intestinal metaplasia (IM) with segments ≥2 cm with areas under the ROC curves (AUC) of 0.72 (95%CI: 0.67–0.77) and 0.81 (95%CI: 0.76–0.86), respectively. The two prediction models included demographics (age, sex), symptoms (heartburn, acid reflux, chest pain, abdominal pain) and medication for “stomach” symptoms. These two models were validated in the independent cohort with AUCs of 0.61 (95%CI: 0.54–0.68) and 0.64 (95%CI: 0.52–0.77) for CLE and IM≥2 cm, respectively.

Conclusions

We have identified and validated two prediction models for CLE and IM≥2 cm. Both models have fair prediction accuracies and can select out around 20% of individuals unlikely to benefit from investigation for Barrett’s esophagus. Such prediction models have the potential to generate useful cost-savings for BE screening among the symptomatic population.

Barrett's oesophagus: epidemiology, cancer risk and implications for management

Although endoscopic surveillance of patients with Barrett's oesophagus has been widely implemented, its effectiveness is debateable. The recently reported low annual oesophageal adenocarcinoma risk in population studies, the failure to identify most Barrett's patients at risk of disease progression, the poor adherence to surveillance and biopsy protocols, and the significant risk of misclassification of dysplasia all tend to undermine the effectiveness of current management, in particular, endoscopic surveillance programmes, to prevent or improve the outcomes of patients with oesophageal adenocarcinoma. The ongoing increase in incidence of Barrett's oesophagus and consequent growth of the surveillance population, together with the associated discomfort and costs of endoscopic surveillance, demand improved techniques for accurately determining individual risk of oesophageal adenocarcinoma. More accurate techniques are needed to run efficient surveillance programmes in the coming decades. In this review, we will discuss the current knowledge on the epidemiology of Barrett's oesophagus, and the challenging epidemiological dilemmas that need to be addressed when assessing the current screening and surveillance strategies.

Gastroesophageal reflux disease, proton-pump inhibitor use and Barrett's esophagus in esophageal adenocarcinoma: Trends revisited

PURPOSE

Screening for esophageal adenocarcinoma (EAC) has not become policy in part over concerns in identifying the high-risk group. It is often claimed that a significant proportion of patients developing EAC do not report preexisting reflux symptoms or prior treatment for gastroesophageal reflux disease (GERD). As such, our aim was to assess the prevalence of GERD symptoms, proton pump inhibitor (PPI) use and Barrett's esophagus (BE) and their impact on survival in patients undergoing esophagectomy for EAC.

METHODS

The study population consisted of 345 consecutive patients who underwent esophagectomy for EAC between 2000 and 2011 at a university-based medical center. Patients with a diagnosis of esophageal squamous cell carcinoma and those who underwent esophagectomy for benign disease were excluded. The prevalence of preoperative GERD symptoms, defined as presence of heartburn, regurgitation or epigastric pain, PPI use (>6 months) and BE, defined by the phrases "Barrett's esophagus," "intestinal epithelium," "specialized epithelium," or "goblet cell metaplasia" in the patients' preoperative clinical notes were retrospectively collected. Overall long-term and stage-specific survival was compared in patients with and without the presence of preoperative GERD symptoms, PPI use, or BE.

RESULTS

The majority of patients (64%; 221/345) had preoperative GERD symptoms and a history of PPI use (52%; 179/345). A preoperative diagnosis of BE was present in 34% (118/345) of patients. Kaplan-Meier survival analysis revealed a marked survival advantage in patients undergoing esophagectomy who had preoperative GERD symptoms, PPI use or BE diagnosis (P ≤ .001). The survival advantage remained when stratified for American Joint Committee on Cancer stage in patients with preoperative PPI use (P = .015) but was less pronounced in patients with GERD symptoms or BE (P = .136 and P = .225, respectively).

CONCLUSION

These data show that the oft-quoted statistic that the majority of patients with EAC do not report preexisting GERD or PPI use is false. Furthermore, a diagnosis of BE is present in a surprisingly high proportion of patients (34%). There is a distinct survival advantage in patients with preoperative GERD symptoms, PPI use, and BE diagnosis, which may not be simply owing to earlier stage at diagnosis. Screening may affect survival outcomes in more patients with EAC than previously anticipated.

MicroRNA expression differentiates squamous epithelium from Barrett's esophagus and esophageal cancer

BACKGROUND

Current strategies fail to identify most patients with esophageal adenocarcinoma (EAC) before the disease becomes advanced and incurable. Given the dismal prognosis associated with EAC, improvements in detection of early-stage esophageal neoplasia are needed.

AIM

We sought to assess whether differential expression of microRNAs could discriminate between squamous epithelium, Barrett's esophagus (BE), and EAC.

METHODS

We analyzed microRNA expression in a discovery cohort of human endoscopic biopsy samples from 36 patients representing normal squamous esophagus (n = 11), BE (n = 14), and high-grade dysplasia/EAC (n = 11). RNA was assessed using microarrays representing 847 human microRNAs followed by quantitative real-time polymerase chain reaction (qRT-PCR) verification of nine microRNAs. In a second cohort (n = 18), qRT-PCR validation of five miRNAs was performed. Expression of 59 microRNAs associated with BE/EAC in the literature was assessed in our training cohort. Known esophageal cell lines were used to compare miRNA expression to tissue miRNAs.

RESULTS

After controlling for multiple comparisons, we found 34 miRNAs differentially expressed between squamous esophagus and BE/EAC by microarray analysis. However, miRNA expression did not reliably differentiate non-dysplastic BE from EAC. In the validation cohort, all five microRNAs selected for qRT-PCR validation differentiated between squamous samples and BE/EAC. Microarray results supported 14 of the previously reported microRNAs associated with BE/EAC in the literature. Cell lines did not generally reflect miRNA expression found in vivo.

CONCLUSIONS

These data indicate that miRNAs differ between squamous esophageal epithelium and BE/EAC, but do not distinguish between BE and EAC. We suggest prospective evaluation of miRNAs in patients at high risk for EAC.

Review on novel concepts of columnar lined esophagus

BACKGROUND

Columnar lined esophagus (CLE) is a marker for gastroesophageal reflux and associates with an increased cancer risk among those with Barrett's esophagus. Recent studies fostered the development of integrated CLE concepts.

METHODS

Using PubMed, we conducted a review of studies on novel histopathological concepts of nondysplastic CLE.

RESULTS

Two histopathological concepts-the squamo-oxyntic gap (SOG) and the dilated distal esophagus (DDE), currently model our novel understanding of CLE. As a consequence of reflux, SOG interposes between the squamous lined esophagus and the oxyntic mucosa of the proximal stomach. Thus the SOG describes the histopathology of CLE within the tubular esophagus and the DDE, which is known to develop at the cost of a shortened lower esophageal sphincter and foster increased acid gastric reflux. Histopathological studies of the lower end of the esophagus indicate, that the DDE is reflux damaged, dilated, gastric type folds forming esophagus and cannot be differentiated from proximal stomach by endoscopy. While the endoscopically visible squamocolumnar junction (SCJ) defines the proximal limit of the SOG, the assessment of the distal limit requires the histopathology of measured multilevel biopsies. Within the SOG, CLE types distribute along a distinct zonation with intestinal metaplasia (IM; Barrett's esophagus) and/or cardiac mucosa (CM) at the SCJ and oxyntocardiac mucosa (OCM) within the distal portion of the SOG. The zonation follows the pH-gradient across the distal esophagus. Diagnosis of SOG and DDE includes endoscopy, histopathology of measured multi-level biopsies from the distal esophagus, function, and radiologic tests. CM and OCM do not require treatment and are surveilled in 5 year intervals, unless they associate with life quality impairing symptoms, which demand medical or surgical therapy. In the presence of an increased cancer risk profile, it is justified to consider radiofrequency ablation (RFA) of IM within clinical studies in order to prevent the progression to dysplasia and cancer. Dysplasia justifies RFA ± endoscopic resection.

CONCLUSIONS

SOG and DDE represent novel concepts fusing the morphological and functional aspects of CLE. Future studies should examine the impact of SOG and DDE for monitoring and management of gastroesophageal reflux disease (GERD).

Upper gastrointestinal cancer and reflux disease

There is a growing evidence that gastroesophageal reflux disease is related to several upper gastrointestinal cancers, mainly the esophageal adenocarcinoma and a certain type of gastric cardia adenocarcinoma. Currently, the incidence of gastroesophageal reflux disease is rapidly increasing in Korea. Therefore, there is a possibility of such increasing cancerous incidents, similar to the western worlds. In this article, the relationship between gastroesophageal reflux disease and several upper gastrointestinal cancers, the components of refluxate which has possible causal relationship with carcinogenesis, and the clinical implications of such relationship in the management of gastroesophageal reflux disease patients are discussed through the review of literature.

Management of Asymptomatic Erosive Esophagitis: An E-Mail Survey of Physician's Opinions

Background/Aims

The management of asymptomatic erosive esophagitis is controversial. We surveyed physicians' opinions on asymptomatic erosive esophagitis using e-mail.

Methods

All members of the Korean Society of Neurogastro-enterology and Motility were invited to answer the questionnaire on the treatment and follow-up of patients with asymptomatic erosive esophagitis by e-mail.

Results

A total of 73 members answered the questionnaire (response rate, 18%). As initial management, 41% of respondents chose pharmacologic treatment, whereas 59% chose nonpharmacologic treatment. In the case of pharmacologic treatment, proton pump inhibitors were the preferred medication. The most common treatment duration was 4 weeks (43%), followed by 8 weeks (38%), and 6 months (11%). Sixty-two percent of the respondents recommended follow-up endoscopy annually, whereas 29% chose no endoscopic follow-up. Thirty-four percent of the respondents answered that they would talk about reflux-related sleep disturbances. Only 25% of the respondents explained the possibility of Barrett's esophagus or esophageal adenocarcinoma to their patients.

Conclusions

There are substantial practice variations in the management of asymptomatic erosive esophagitis in Korea.

Early diagnostic biomarkers for esophageal adenocarcinoma--the current state of play

Esophageal adenocarcinoma (EAC) is one of the two most common types of esophageal cancer with alarming increase in incidence and very poor prognosis. Aiming to detect EAC early, currently high-risk patients are monitored using an endoscopic-biopsy approach. However, this approach is prone to sampling error and interobserver variability. Diagnostic tissue biomarkers related to genomic and cell-cycle abnormalities have shown promising results, although with current technology these tests are difficult to implement in the screening of high-risk patients for early neoplastic changes. Differential miRNA profiles and aberrant protein glycosylation in tissue samples have been reported to improve performance of existing tissue-based diagnostic biomarkers. In contrast to tissue biomarkers, circulating biomarkers are more amenable to population-screening strategies, due to the ease and low cost of testing. Studies have already shown altered circulating glycans and DNA methylation in BE/EAC, whereas disease-associated changes in circulating miRNA remain to be determined. Future research should focus on identification and validation of these circulating biomarkers in large-scale trials to develop in vitro diagnostic tools to screen population at risk for EAC development.

Editorial: Predicting the risk of Barrett's esophagus: does the BERET fit?

Symptoms of gastroesophageal reflux are the only commonly used criterion for endoscopic screening for esophageal adenocarcinoma (EAC). Recent research has elucidated multiple other risk factors for both EAC and Barrett's esophagus (BE). Utilization of these risk factors may allow for the selection of a screening population with a much higher pre-test probability of disease. A recently developed risk-prediction model for BE is a significant step in the right direction; however, further refinements in this model will likely be necessary to optimize utility. Our inability to prognosticate cancer risk in BE does temper enthusiasm for increasing the pool of patients under endoscopic surveillance for BE, and again highlights the need for better, cheaper, and more accurate means of stratifying cancer risk in BE.

Anterior gradient 2 profiling in Barrett columnar epithelia and adenocarcinoma

Barrett esophagus is the precancerous lesion leading to Barrett adenocarcinoma. The natural history of Barrett metaplasia and its neoplastic progression are still controversial. Anterior gradient 2 is up-regulated in both Barrett intestinal metaplasia and Barrett adenocarcinoma, but no information is available on anterior gradient 2 expression in the spectrum of the phenotypic changes occurring in the natural history of Barrett adenocarcinoma (Barrett esophagus cardiac-type metaplasia, Barrett esophagus intestinal metaplasia, low-grade intraepithelial neoplasia [formerly called low-grade dysplasia], and high-grade intraepithelial neoplasia [formerly called high-grade dysplasia]). Applying immunohistochemistry and reverse transcription and quantitative real-time polymerase chain reaction, this study addressed the role of anterior gradient 2 in Barrett carcinogenesis. Anterior gradient 2 expression was assessed semiquantitatively in 125 consecutive biopsy samples in the adenocarcinoma spectrum arising in Barrett esophagus (Barrett esophagus cardiac-type metaplasia, 25; Barrett esophagus intestinal metaplasia, 25; low-grade intraepithelial neoplasia, 25; high-grade intraepithelial neoplasia, 25; Barrett adenocarcinoma, 25). Additional biopsy samples of esophageal squamous mucosa (n=25) served as controls. Anterior gradient 2 messenger RNA expression was also tested (reverse transcription and quantitative real-time polymerase chain reaction) in a different series of 40 samples (esophageal squamous mucosa, 10; Barrett esophagus cardiac-type metaplasia, 10; Barrett esophagus intestinal metaplasia, 10; Barrett adenocarcinoma, 10). Anterior gradient 2 was never expressed in squamous esophageal epithelium but consistently overexpressed (to much the same degree) in the whole spectrum of Barrett disease (Barrett esophagus cardiac-type metaplasia, Barrett esophagus intestinal metaplasia, low-grade intraepithelial neoplasia, high-grade intraepithelial neoplasia, and Barrett adenocarcinoma). Anterior gradient 2 messenger RNA was expressed significantly more in Barrett esophagus cardiac-type metaplasia, Barrett esophagus intestinal metaplasia, and Barrett adenocarcinoma than in native squamous epithelium (P<.001), with no significant differences between the 3 groups. Anterior gradient 2 overexpression affects the whole spectrum of the metaplastic/neoplastic lesions involved in Barrett carcinogenesis. This study supports the biological similarity of the nonintestinal and intestinal types of Barrett metaplasia as precursors of Barrett adenocarcinoma.

Surveillance for gastrointestinal malignancies

Gastrointestinal (GI) malignancies are notorious for frequently progressing to advanced stages even in the absence of serious symptoms, thus leading to delayed diagnoses and dismal prognoses. Secondary prevention of GI malignancies through early detection and treatment of cancer-precursor/premalignant lesions, therefore, is recognized as an effective cancer prevention strategy. In order to efficiently detect these lesions, systemic application of screening tests (surveillance) is needed. However, most of the currently used non-invasive screening tests for GI malignancies (for example, serum markers such as alpha-fetoprotein for hepatocellular carcinoma, and fecal occult blood test, for colon cancer) are only modestly effective necessitating the use of highly invasive endoscopy-based procedures, such as esophagogastroduodenoscopy and colonoscopy for screening purposes. Even for hepatocellular carcinoma where non-invasive imaging (ultrasonography) has become a standard screening tool, the need for repeated liver biopsies of suspicious liver nodules for histopathological confirmation can’t be avoided. The invasive nature and high-cost associated with these screening tools hinders implementation of GI cancer screening programs. Moreover, only a small fraction of general population is truly predisposed to developing GI malignancies, and indeed needs surveillance. To spare the average-risk individuals from superfluous invasive procedures and achieve an economically viable model of cancer prevention, it’s important to identify cohorts in general population that are at substantially high risk of developing GI malignancies (risk-stratification), and select suitable screening tests for surveillance in these cohorts. We herein provide a brief overview of such high-risk cohorts for different GI malignancies, and the screening strategies that have commonly been employed for surveillance purpose in them.

Barrett's Esophagus: Emerging Knowledge and Management Strategies

The incidence of esophageal adenocarcinoma (EAC) has increased exponentially in the last 3 decades. Barrett's esophagus (BE) is the only known precursor of EAC. Patients with BE have a greater than 40 folds higher risk of EAC compared with the general population. Recent years have witnessed a revolution in the clinical and molecular research related to BE. However, several aspects of this condition remain controversial. Data regarding the true prevalence of BE have varied widely. Recent studies have suggested a lower incidence of EAC in nondysplastic BE (NDBE) than previously reported. There is paucity of prospective data showing a survival benefit of screening or surveillance for BE. Furthermore, the ever-increasing emphasis on healthcare cost containment has called for reexamination of the screening and surveillance strategies for BE. There is a need for identification of reliable clinical predictors or molecular biomarkers to risk-stratify patients who might benefit the most from screening or surveillance for BE. Finally, new therapies have emerged for the management of dysplastic BE. In this paper, we highlight the key areas of controversy and uncertainty surrounding BE. The paper discusses, in detail, the current literature about the molecular pathogenesis, biomarkers, histopathological diagnosis, and management strategies for BE.

Feasibility, safety, acceptability, and yield of office-based, screening transnasal esophagoscopy (with video)

BACKGROUND

Endoscopic screening for esophageal neoplasia can identify patients eligible for early intervention for precancerous lesions. Unsedated transnasal esophagoscopy may provide an efficient and accurate endoscopic assessment with fewer risks and less cost, compared with conventional upper endoscopy.

OBJECTIVE

To assess the feasibility, safety, acceptability, and yield of unsedated transnasal esophagoscopy in a primary care population.

DESIGN

Multicenter, prospective, cross-sectional study.

SETTING

Two outpatient tertiary-care centers.

PATIENTS

This study involved a general medical clinic population aged between 40 and 85 years.

INTERVENTION

Unsedated, office-based transnasal esophagoscopy.

MAIN OUTCOME MEASUREMENTS

Procedure yield; completeness of examination; procedure length; adverse events and complications; choking, gagging, pain, or anxiety during the examination; and overall tolerability.

RESULTS

A total of 426 participants (mean [± standard deviation] age 55.8 ± 9.5 years; 43% male) enrolled in the study, and 422 (99%) completed the examination. Mean (± standard deviation) examination time was 3.7 ± 1.8 minutes. There were no serious adverse events, and 12 participants (2.8%) reported minor complications. Participants reported minimal choking, gagging, pain, or anxiety. The examination was well-tolerated by most participants. Overall, 38% of participants had an esophageal finding that changed management (34% erosive esophagitis, 4% Barrett's esophagus).

LIMITATIONS

Nonrandomized study, tertiary-care centers only, self-selected population with a large proportion reporting esophageal symptoms.

CONCLUSION

Unsedated transnasal esophagoscopy is a feasible, safe, and well-tolerated method to screen for esophageal disease in a primary care population. Endoscopic findings are common in this patient population.

Squamous cell carcinoma in Barrett's esophagus: field effect versus metastasis

Barrett's esophagus (BE) is a premalignant condition with an increased risk of developing esophageal adenocarcinoma (EAC). Risk factors for EAC overlap with those for esophageal squamous cell carcinoma (ESCC), but ESCC is surprisingly rare in BE. We report two cases of ESCC directly surrounded by BE. Both patients had a previous medical history of cancers, i.e., head and neck squamous cell carcinomas, and were using alcohol and smoking tobacco. Using immunohistochemistry for p63, CK5, CK7, and CDX2, it was confirmed that these carcinomas were pure squamous cell carcinomas, and not EACs or esophageal adenosquamous carcinomas arising from BE. Using TP53 mutation and loss of heterozygosity analysis, we established that the ESCCs in BE were not metastases of the previously diagnosed head and neck squamous cell carcinomas but de novo primary ESCCs. This study shows the strength of molecular analysis as an adjunct to the histopathologic diagnosis for distinguishing between metastases of prior cancers and primary cancers. Furthermore, these cases imply that presence of BE is not protective with regards to developing ESCC in the lower one third of the esophagus. We suggest that their ESCCs arose from islets of squamous epithelium in BE.

Prevalence of Barrett esophagus in first-degree relatives of patients with esophageal adenocarcinoma

AIM

The aim of this study is to determine the prevalence of Barrett esophagus (BE) in first-degree relatives of patients with esophageal adenocarcinoma (EAC) and Barrett high-grade dysplasia (HGD).

METHODS

After Institutional Review Board approval, first-degree relatives of patients with EAC/HGD underwent unsedated ultrathin transnasal endoscopy (UUTNE) with biopsy. BE was suspected if any salmon-colored epithelial tongues were seen above the gastroesophageal junction. A diagnosis of BE was made only if biopsy from these areas confirmed columnar-lined epithelium with intestinal metaplasia.

RESULTS

From 23 families, 47 first-degree relatives underwent ultrathin transnasal endoscopy and 1 patient underwent routine upper endoscopy with sedation as part of this study. The mean age of cases was 44.4 years. All patients tolerated the procedure well and there were no procedure-related complications. BE was suspected in 16 (34%) patients and confirmed in 13 of 16 (27.7%) patients. There were 4 long segments (>3 cm) and 9 short segments (<3 cm) of BE.

CONCLUSION

There is a significantly higher than expected prevalence of BE in first-degree relatives of patients with EAC/HGD. This should be taken in to consideration to develop further screening guidelines. Further work is needed to confirm these findings. Unsedated transnasal endoscopy is a safe and well-tolerated method for BE screening.

Incidence of adenocarcinoma among patients with Barrett's esophagus

BACKGROUND

Accurate population-based data are needed on the incidence of esophageal adenocarcinoma and high-grade dysplasia among patients with Barrett's esophagus.

METHODS

We conducted a nationwide, population-based, cohort study involving all patients with Barrett's esophagus in Denmark during the period from 1992 through 2009, using data from the Danish Pathology Registry and the Danish Cancer Registry. We determined the incidence rates (numbers of cases per 1000 person-years) of adenocarcinoma and high-grade dysplasia. As a measure of relative risk, standardized incidence ratios were calculated with the use of national cancer rates in Denmark during the study period.

RESULTS

We identified 11,028 patients with Barrett's esophagus and analyzed their data for a median of 5.2 years. Within the first year after the index endoscopy, 131 new cases of adenocarcinoma were diagnosed. During subsequent years, 66 new adenocarcinomas were detected, yielding an incidence rate for adenocarcinoma of 1.2 cases per 1000 person-years (95% confidence interval [CI], 0.9 to 1.5). As compared with the risk in the general population, the relative risk of adenocarcinoma among patients with Barrett's esophagus was 11.3 (95% CI, 8.8 to 14.4). The annual risk of esophageal adenocarcinoma was 0.12% (95% CI, 0.09 to 0.15). Detection of low-grade dysplasia on the index endoscopy was associated with an incidence rate for adenocarcinoma of 5.1 cases per 1000 person-years. In contrast, the incidence rate among patients without dysplasia was 1.0 case per 1000 person-years. Risk estimates for patients with high-grade dysplasia were slightly higher.

CONCLUSIONS

Barrett's esophagus is a strong risk factor for esophageal adenocarcinoma, but the absolute annual risk, 0.12%, is much lower than the assumed risk of 0.5%, which is the basis for current surveillance guidelines. Data from the current study call into question the rationale for ongoing surveillance in patients who have Barrett's esophagus without dysplasia. (Funded by the Clinical Institute, University of Aarhus, Aarhus, Denmark.).

Gastroesophageal reflux disease symptom severity, proton pump inhibitor use, and esophageal carcinogenesis

HYPOTHESIS

Screening for esophageal adenocarcinoma has focused on identifying Barrett esophagus (BE) in patients with severe, long-standing symptoms of gastroesophageal reflux disease (GERD). Unfortunately, 95% of patients who develop esophageal adenocarcinoma are unaware of the presence of BE before their cancer diagnosis, which means they never had been selected for screening. One possible explanation is that no correlation exists between the severity of GERD symptoms and cancer risk. We hypothesize that severe GERD symptoms are not associated with an increase in the prevalence of BE, dysplasia, or cancer in patients undergoing primary endoscopic screening.

DESIGN

Cross-sectional study.

SETTING

University hospital.

PATIENTS

A total of 769 patients with GERD.

INTERVENTIONS

Primary screening endoscopy performed from November 1, 2004, through June 7, 2007.

MAIN OUTCOMES MEASURES

Symptom severity, proton pump inhibitor therapy, and esophageal adenocarcinogenesis (ie, BE, dysplasia, or cancer).

RESULTS

Endoscopy revealed adenocarcinogenesis in 122 patients. An increasing number of severe GERD symptoms correlated positively with endoscopic findings of esophagitis (odds ratio, 1.05; 95% confidence interval, 1.01-1.09). Conversely, an increasing number of severe GERD symptoms were associated with decreased odds of adenocarcinogenesis (odds ratio, 0.94; 95% confidence interval, 0.89-0.98). Patients taking proton pump inhibitors were 61.3% and 81.5% more likely to have adenocarcinogenesis if they reported no severe typical or atypical GERD symptoms, respectively, compared with patients taking proton pump inhibitors, who reported that all symptoms were severe.

CONCLUSIONS

Medically treated patients with mild or absent GERD symptoms have significantly higher odds of adenocarcinogenesis compared with medically treated patients with severe GERD symptoms. This finding may explain the failure of the current screening paradigm in which the threshold for primary endoscopic examination is based on symptom severity.

Ablative therapies for Barrett's esophagus

Barrett's esophagus has gained increased clinical attention because of its association with esophageal adenocarcinoma, a cancer with increasing incidence and poor survival rates. The goals of ablating Barrett's esophagus are to decrease esophageal cancer rates and to improve overall survival and quality of life. Different techniques have been developed and tested for their effectiveness eradicating Barrett's epithelium. This review assesses the literature associated with different ablative techniques. The safety and efficacy of different techniques are discussed. This review concludes with recommendations for the clinician, including specific strategies for patient care decisions for patients with Barrett's esophagus with varying degrees of dysplasia.

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.

Biology of Barrett's esophagus and esophageal adenocarcinoma

The past few years have brought new advances in our understanding of the molecular mechanisms underlying the development of Barrett's esophagus and esophageal adenocarcinoma. Although knowledge of the genetic basis for these conditions has not yet translated into clinically useful biomarkers, the current pace of biomedical discovery holds endless possibilities for molecular medicine to improve the diagnosis and management of patients with these conditions. This article provides a useful conceptual basis for understanding the molecular events involved in the making of Barrett metaplasia and in its neoplastic progression, and provides a rationale for evaluating studies on the application of molecular medicine to the diagnosis and management of patients with Barrett's esophagus and esophageal adenocarcinoma.

Short-segment Barrett’s esophagus and cardia intestinal metaplasia: A comparative analysis

AIM: To investigate the endoscopy and histology of short-segment Barrett’s esophagus (SSBE) and cardia intestinal metaplasia (CIM), and their correlation with Helicobacter pylori (H. pylori) gastritis and gastroesophageal reflux disease (GERD).

METHODS: Biopsy specimens were taken from 32 SSBE patients and 41 CIM patients with normal appearance of the esophagogastric junction. Eight biopsy specimens from the lower esophagus, cardia, and gastric antrum were stained with hematoxylin/eosin, Alcian blue/periodic acid-Schiff, Alcian blue/high iron diamine and Gimenez dye. Results were graded independently by one pathologist.

RESULTS: The SSBE patients were younger than the CIM patients (P < 0.01). The incidence of dysplasia and incomplete intestinal metaplasia subtype was higher in SSBE patients than in CIM patients (P < 0.01). H. pylori infection was correlated with antral intestinal metaplasia (P < 0.05), but not with reflux symptomatic, endoscopic, or histological markers of GERD in CIM patients. SSBE was correlated with reflux symptomatic and endoscopic esophagitis (P < 0.01), but not with H. pylori infection and antral intestinal metaplasia.

CONCLUSION: Dysplasia risk is significantly greater in SSBE patients than in CIM patients. CIM is a manifestation of H. pylori-associated and multifocal atrophic gastritis, whereas SSBE may result from GERD.

The value of epigenetic markers in esophageal cancer

Developing esophageal cancer is a multi-step process that begins with the accumulation of genetic and epigenetic alterations, and leads to the activation of oncogenes and the inactivation or loss of tumor suppressor genes (TSG). In addition to genetic alteration, epigenetic modifications, and in particular DNA methylation, are recognized as a common molecular alteration in human tumors. In esophageal cancer, aberrant methylation of promoter regions occurs not only in advanced cancer, but also in premalignant lesions. DNA methylation is related to survival time and sensitivity of chemoradiotherapy. This review is mainly focused on epigenetic changes in esophageal cancer and the value of early detection for patient prognosis, treatment choices, and potential targeting therapy.

Biomarkers and molecular diagnosis of gastrointestinal and pancreatic neoplasms

Standard protocols for the diagnosis of neoplasms in the gastrointestinal tract are based on histopathologic analysis in combination with clinical information. With the completion of the Human Genome Project in 2003, our understanding of the contribution of genetics to human disease has increased exponentially. This knowledge is gradually being incorporated into clinical decision-making. However, the rate at which molecular biomarkers are validated for use in mainstream clinical applications has lagged far behind that of biomarker discovery. Nevertheless, a number of molecular biomarkers are available for use in the diagnosis and management of gastrointestinal tract neoplasms. This article reviews the most common molecular biomarkers currently available for neoplasms of the luminal gastrointestinal tract and pancreas. In neoplasms of the esophagus, for which no biomarkers are currently used in routine clinical practice, those that have shown the most promise in early clinical validation studies are discussed.

Barrett's surveillance identifies patients with early esophageal adenocarcinoma

BACKGROUND

Barrett's surveillance for dysplasia is recommended, but few studies have documented the benefit of endoscopic surveillance for dysplasia or cancer.

OBJECTIVES

Using a retrospective study design, we aim to demonstrate the impact of a Barrett's surveillance program on the stage of esophageal adenocarcinoma and identify factors for progression of metaplasia to cancer.

SUBJECTS

The Institutional Review Board at Veterans Affairs Connecticut Healthcare approved the study. We report a retrospective review of a prospectively followed Barrett's cohort in a surveillance program and compared their outcome with patients with a new diagnosis of esophageal adenocarcinoma, identified at the same center between 1999 and 2005.

RESULTS

There were 248 patients with Barrett's esophagus entered into a surveillance program from 1999 to 2005. During the surveillance period of 987 patient-years, 5 (0.5% patient-year) patients developed esophageal adenocarcinoma. During the same period, 46 patients were diagnosed with new-onset esophageal adenocarcinoma outside of our surveillance program. Only 5% of these patients had a history of gastroesophageal reflux disease. There were 248 patients who underwent a mean number of 2.7+/-1.7 upper endoscopic procedures, with 26 (10%) patients developing dysplasia. Compared with nonsurveillance, more patients had early stage of cancer in the surveillance group (P <.001). All 5 patients with cancer diagnosed from Barrett's esophagus surveillance endoscopy were alive, compared with 20 of 46 (43%) patients with cancer diagnosed outside of the surveillance program. The length of Barrett's segment >3 cm was found to be associated with development of dysplasia, P=.004 (odds ratio 1.2; 95% confidence interval, 1.07-1.34).

CONCLUSION

Patients with Barrett's esophagus undergoing endoscopic surveillance benefit from early-stage cancer diagnosis. Progression to adenocarcinoma is low, but long-segment and high-grade dysplasias have an increased risk of cancer. A significant number of patients with newly diagnosed esophageal adenocarcinoma do not complain of gastroesophageal reflux disease and are therefore not investigated for Barrett's esophagus nor entered into surveillance. Patients and physicians can use this information in making a decision about surveillance.

Time trends of endoscopic and pathological diagnoses related to gastroesophageal reflux disease in a Chinese population: eight years single institution experience

The discrepancy between Eastern and Western countries exists regarding the time trends of Barrett's esophagus (BE)/adenocarcinoma. We aimed to elucidate this issue through a retrospective review of the endoscopic and pathological diagnoses of gastroesophageal reflux disease (GERD) over time in a Chinese population. All records were analyzed from 2000 to 2007. Records included demographic data, clinical indication for endoscopy, and endoscopic findings. The total number of endoscopic procedures increased over time. The indications for referral endoscopy secondary to GERD increased from 366 cases (4.9%) in the beginning of the study to 1439 cases (14.1%) at the end. Concomitant GERD symptoms did not significantly change (range, 13-15.1%) in screening endoscopic studies. Endoscopic detection of erosive esophagitis increased in referral populations from 1546 (20.7%) to 5207 cases (51%) and by screening endoscopy from 791 (14.5%) to 1983 cases (23.5%). The prevalence of nonerosive reflux disease and BE did not change over time. BE-associated dysplasia and adenocarcinoma were rare. The detection of Los Angeles class A disease increased with time in referral endoscopy cases with a focus on erosive esophagitis composition. The endoscopic demand for GERD investigation and the GERD endoscopic diagnosis increased in our population. The results were related to a higher prevalence of low-grade erosive disease diagnosed. The incidence of BE-associated dysplasia and adenocarcinoma has been the same and the increased screening did not detect more cancers.

Barrett's oesophagus and oesophageal adenocarcinoma: time for a new synthesis

The public health importance of Barrett's oesophagus lies in its association with oesophageal adenocarcinoma. The incidence of oesophageal adenocarcinoma has risen at an alarming rate over the past four decades in many regions of the Western world, and there are indications that the incidence of this disease is on the rise in Asian populations in which it has been rare. Much has been learned of host and environmental risk factors that affect the incidence of oesophageal adenocarcinoma, and data indicate that patients with Barrett's oesophagus rarely develop oesophageal adenocarcinoma. Given that 95% of oesophageal adenocarcinomas arise in individuals without a prior diagnosis of Barrett's oesophagus, what strategies can be used to reduce late diagnosis of oesophageal adenocarcinoma?

Preemptive surgery for premalignant foregut lesions

INTRODUCTION

Preemptive surgery is the prophylactic removal of an organ at high risk for malignant transformation or the resection of a precancerous or "early" malignant neoplasm in an individual with a hereditary predisposition to cancer. Recent advances in molecular diagnostic techniques have improved our understanding of the biologic behavior of these conditions. Predictive testing is an emerging field that attempts to assess the potential risk of cancer development in predisposed individuals. Despite substantial improvement in these forms of testing, all results are imperfect. This information often becomes an important tool that is used by healthcare providers to evaluate the risk-benefit ratio of various risk modifying strategies (i.e., intensive surveillance or preemptive surgery).

METHODS

A systematic literature review was performed using Medline and the bibliographies of all referenced publications to identify articles relating to preemptive surgery for premalignant foregut lesions.

RESULTS AND DISCUSSION

In this review, we outline the controversies surrounding predictive risk assessment, surveillance strategies, and preemptive surgery in the management of high-grade dysplasia (HGD) in Barrett's esophagus (BE), hereditary diffuse gastric cancer (HDGC), bile duct cysts, primary sclerosing cholangitis (PSC), and pancreatic cystic neoplasms. Resection of BE is supported by the progressive nature of the disease, the risk of occult carcinoma, and the lethality of esophageal cancer. Prophylactic total gastrectomy for HDGC appears reasonable in the absence of accurate screening tests but must be balanced by the impact of surgical complications and altered quality of life. Surgical resection of biliary cysts theoretically eliminates the exposed epithelium to decrease the lifetime risk of cholangiocarcinoma. Liver transplantation for PSC remains controversial given the scarcity of donor organs and inability to accurately identify high-risk individuals. Given the uncertain natural history of pancreatic cystic neoplasms, the merits of selective versus obligatory resection will continue to be debated.

CONCLUSIONS

Preemptive operations require optimal judgment and surgical precision to maximize function and enhance survival. Ultimately, balancing the risk of surgical intervention with less invasive interventions or observation must be individualized on a case-by-case basis.

MicroRNAs in Barrett's esophagus and esophageal adenocarcinoma

The molecular genetics of Barrett's esophagus (BE) and its evolution to esophageal adenocarcinoma (EAC) have been widely studied; however, the molecular mechanism of BE-EAC carcinogenesis has not been completely understood. MicroRNA (miRNA) is now essential to understand the molecular mechanism of cancer progression. Recent findings include the following: firstly, miRNA expression profiles can distinguish between BE and EAC; secondly, miR-196a is upregulated in EAC tissues targeting annexin A1, thereby exerting antiapoptotic effects and contributing to EAC cell survival; miR-196a may also constitute a good biomarker of progression during BE-EAC carcinogenesis; and thirdly, The miR-106b-25 polycistron is activated by genomic amplification and is involved in esophageal neoplastic progression and proliferation via the suppression of two target genes, p21 and Bim.

Differences in genetic instability and cellular phenotype among Barrett's, cardiac, and gastric intestinal metaplasia in a Japanese population with Helicobacter pylori

AIMS

Intestinal metaplasia is considered to be a precursor lesion in both Barrett's and intestinal-type gastric cancer. The aim was to clarify the differences in molecular pathology between specialized intestinal metaplasia (SIM) in Barrett's oesophagus (BO), cardiac (CIM) and gastric intestinal metaplasia (GIM).

METHODS AND RESULTS

Eighty-eight SIM cases with BO, 30 CIM cases and 52 GIM cases in patients with or without Helicobacter pylori infectionwere analysed for genetic instability and Das-1. Microsatellite instability and a loss of heterozygosity were evaluated at five microsatellite loci. The incidence of genetic instability was 55.7% in SIM, 40.0% in CIM and 23.1% in GIM, revealing a significant difference between SIM and GIM (P < 0.0005). For each microsatellite marker analysed, there were obvious differences in frequency among the three conditions. Das-1 reactivity was significantly higher in SIM than in CIM or GIM (P < 0.0001, both). Interestingly, both genetic instability and Das-1 reactivity in SIM showed a significantly higher incidence in patients with H. pylori infection than in those without (P < 0.005 and P < 0.01, respectively).

CONCLUSIONS

SIM is distinct from CIM and GIM, and the pathogenesis of SIM, like that of GIM, is associated to some degree with H. pylori infection in a Japanese population.