Barrett's esophagus: pathogenesis, epidemiology, functional abnormalities, malignant degeneration, and surgical management

Management of high risk T1 esophageal adenocarcinoma following endoscopic resection

High-risk T1 esophageal adenocarcinoma (HR-T1 EAC) is defined as T1 cancer, with one or more of the following histological criteria: submucosal invasion, poorly or undifferentiated cancer, and/or presence of lympho-vascular invasion. Esophagectomy has long been the only available treatment for these HR-T1 EACs and was considered necessary because of a presumed high risk of lymph node metastases up to 46%. However, endoscopic submucosal disscection have made it possible to radically remove HR-T1 EAC, irrespective of size, while leaving the esophageal anatomy intact. Parallel to this development, new publications demonstrated that the risk of lymph node metastases for HR-T1 EAC may be even <24%. Therefore, indications for endoscopic treatment of HR-T1 EAC are being reconsidered and current research aims at finding the optimal management strategy for this indication, where watchful waiting may proof to be an acceptable strategy in selected patients. In this review, we will discuss the latest developments in this field.

Key molecules involved in the Th17/Treg balance are associated with the pathogenesis of reflux esophagitis and Barrett's esophagus

BACKGROUND

Reflux esophagitis (RE) impairs the squamous epithelium that normally lines the esophagus, and contributes to the replacement of the damaged squamous lining by the intestinal metaplasia of Barrett's esophagus (BE), which is considered as a precursor of esophageal adenocarcinoma. This study aimed to investigate the changes in the balance of Th17/Treg and the related key molecules in the pathogenesis of RE and BE and evaluate the diagnostic and predictive value of the molecules in patients with these diseases.

METHODS

The proportions of Th17 and Treg in RE and BE patients were estimated using flow cytometric analysis. Key molecules involving in the Th17/Treg balance, including RORγt, Foxp3, IL-17, IL-6, IL-10, and TGF-β, were measured using quantitative real-time PCR (qRT-PCR) and ELISA analyses. The diagnostic and predictive value of the Th17/Treg ratio and its key regulators was evaluated using a receiver operating characteristic assay (ROC). In addition, the Spearman correlation analysis explored the relationship between the Th17/Treg ratio and the clinical characteristics.

RESULTS

An increased ratio of Th17/Treg was observed in RE and BE compared with the normal controls, and the proportion of Th17/Treg in BE was further increased compared with RE patients. Moreover, the expression levels of RORγt, IL-17, IL-6, and TGF-β were elevated, while the levels of Foxp3 and IL-10 were reduced in patients when compared to the controls. Compared with the RE groups, the levels of IL-17 were significantly higher in BE patients, while the Foxp3 levels were significant decreased. In addition, the Th17/Treg ratio also showed high diagnostic significance and considerable predictive value for the clinical outcomes in patients with RE and BE.

CONCLUSION

The balance of Th17/Treg was impaired in patients with RE and BE. Th17/Treg may be involved in the development of both RE and BE through regulating the release of inflammatory cytokines, but the concrete mechanisms maybe different in the two diseases. The imbalance of Th17/Treg ratio and the related key molecules had a certain clinical diagnosis and prediction potential for RE and BE.

Optimizing Outcomes with Radiofrequency Ablation of Barrett's Esophagus: Candidates, Efficacy and Durability

The treatment of early Barrett's esophagus (BE) has undergone a paradigm shift from surgical subtotal esophagectomy to organ-saving endoluminal treatment. Over the past 15 years, several high-quality studies were conducted to assess safe oncological outcome of endoscopic resection of mucosal adenocarcinoma and high-grade dysplasia. It became clear that add-on ablative therapy with radiofrequency ablation (RFA) significantly reduces recurrence risk of neoplasia after resection. In this review, we highlight the most essential elements to optimize outcomes of RFA of BE, addressing the correct indication and patient selection in combination with the most efficient and safest treatment protocols to obtain long-term durability.

G. H, Macleod A, Prasanth M, Zafar M, Hemadasa N, Neagle G, Rosindell I, Apollos J. A predictive Bayesian network that risk stratifies patients undergoing Barrett's surveillance for personalized risk of developing malignancy

BACKGROUND

Barrett's esophagus is strongly associated with esophageal adenocarcinoma. Considering costs and risks associated with invasive surveillance endoscopies better methods of risk stratification are required to assist decision-making and move toward more personalised tailoring of Barrett's surveillance.

METHODS

A Bayesian network was created by synthesizing data from published studies analysing risk factors for developing adenocarcinoma in Barrett's oesophagus through a two-stage weighting process.

RESULTS

Data was synthesized from 114 studies (n = 394,827) to create the Bayesian network, which was validated against a prospectively maintained institutional database (n = 571). Version 1 contained 10 variables (dysplasia, gender, age, Barrett's segment length, statin use, proton pump inhibitor use, BMI, smoking, aspirin and NSAID use) and achieved AUC of 0.61. Version 2 contained 4 variables with the strongest evidence of association with the development of adenocarcinoma in Barrett's (dysplasia, gender, age, Barrett's segment length) and achieved an AUC 0.90.

CONCLUSION

This Bayesian network is unique in the way it utilizes published data to translate the existing empirical evidence surrounding the risk of developing adenocarcinoma in Barrett's esophagus to make personalized risk predictions. Further work is required but this tool marks a vital step towards delivering a more personalized approach to Barrett's surveillance.

Evidence that dysplasia related microRNAs in Barrett's esophagus target PD-L1 expression and contribute to the development of esophageal adenocarcinoma

Esophageal adenocarcinoma (EAC) is the cancer arising from the esophagus, which frequently develop from Barrett's esophagus (BE). Extracellular vesicles (EVs), particularly exosomes, are nanosized vesicles of endosomal origin released from various types of cells that have been implicated in cancers. However, the significance of circulating exosomes during the progression of BE to EAC remains unknown. Sera exosmal microRNAs were profiled from 13 EAC and 12BE patients compared to 12 healthy controls. We found a substantial dysregulation of exosomal miRNA levels in BE compared to healthy control, and identified a unique signature of 24 up regulated and 14 down regulated miRNAs. Further validation showed exosomal miR-196a, -26b, -21, and -143 expression was significantly higher in BE and continued to have higher levels in EAC compared to healthy controls; while sera exosomal miR-378, -210, -205, and -200c-3p were significantly lower expressed in BE patients compared to compared to controls. Further, miR-378, -210, -205, and -200c-3p continue to have even lower levels in EAC patients compared to BE. Interestingly, sera expression levels of exosomal miR-15a, -16, and -193a-3p were significantly down regulated in BE PD-L1(+) patients; Sera exosomal miR-15a, -15b, -16, and -193a-3p expression levels in EAC PD-L1(+) patients were significantly lower (all p < 0.01) when compared to EAC PD-L1(-) patients. More importantly, the BE-EAC group had longitudinally decreased exosomal expression levels of miR-15a, -15b, -16, and -193a-3p from BE status to their EAC progression. In conclusion, distinct microRNA expression patterns were demonstrated in circulating exosomes from Barrett's esophagus and esophageal adenocarcinoma; Furthermore exosomal microRNAs potentially targeting PD-L1 mRNA were down regulated in PD-L1 (+) BE and EAC patients.

A Systematic Review and Meta-Analysis of the Effect of Roux-en-Y Gastric Bypass on Barrett's Esophagus

BACKGROUND

Obesity is associated with a twofold risk of gastroesophageal reflux disease (GERD) and thrice the risk of Barrett's esophagus (BE). Roux-en-Y gastric bypass (RYGB) leads to weight loss and improvement of GERD in population with obesity, but its effect on BE is less clear.

METHODS

Bibliographic databases were searched systematically for relevant articles till January 31, 2019. Studies evaluating the effect of RYGB on BE with preoperative and postoperative endoscopy and biopsy were included. Study quality was assessed using the Methodological Index for Non-Randomized Studies (MINORS) tool. Meta-analysis was conducted using Mantel-Haenszel, random effects model and presented as risk difference (RD) or odds ratio (OR) with 95% confidence intervals.

RESULTS

Eight studies with 10,779 patients undergoing RYGB reported on 117 patients with BE with follow-up of > 1 year. Significant regression of BE after RYGB was observed (RD - 0.56.95% c.i. - 0.69 to - 0.43; P < 0.001). Subgroup analysis showed regression of both short-segment BE [ssBE] (RD - 0.51.95% c.i. - 0.68 to - 0.33; P < 0.001) and long-segment BE [lsBE] (RD - 0.46.95% c.i. - 0.71 to - 0.21; P < 0.001). RYGB also caused improvement in GERD in patients of BE (RD - 0.93, 95% c.i. - 1.04 to - 0.81; P < 0.001). RYGB was strongly associated with regression of BE compared with progression (OR 31.2.95% c.i. 11.37 to 85.63; P < 0.001).

CONCLUSIONS

RYGB leads to significant improvement of BE at > 1 year after surgery in terms of regression and resolution of the associated GERD. Both ssBE and lsBE improve after RYGB significantly.

Attention-Based Deep Neural Networks for Detection of Cancerous and Precancerous Esophagus Tissue on Histopathological Slides

Importance

Deep learning-based methods, such as the sliding window approach for cropped-image classification and heuristic aggregation for whole-slide inference, for analyzing histological patterns in high-resolution microscopy images have shown promising results. These approaches, however, require a laborious annotation process and are fragmented.

Objective

To evaluate a novel deep learning method that uses tissue-level annotations for high-resolution histological image analysis for Barrett esophagus (BE) and esophageal adenocarcinoma detection.

Design, Setting, and Participants

This diagnostic study collected deidentified high-resolution histological images (N = 379) for training a new model composed of a convolutional neural network and a grid-based attention network. Histological images of patients who underwent endoscopic esophagus and gastroesophageal junction mucosal biopsy between January 1, 2016, and December 31, 2018, at Dartmouth-Hitchcock Medical Center (Lebanon, New Hampshire) were collected.

Main Outcomes and Measures

The model was evaluated on an independent testing set of 123 histological images with 4 classes: normal, BE-no-dysplasia, BE-with-dysplasia, and adenocarcinoma. Performance of this model was measured and compared with that of the current state-of-the-art sliding window approach using the following standard machine learning metrics: accuracy, recall, precision, and F1 score.

Results

Of the independent testing set of 123 histological images, 30 (24.4%) were in the BE-no-dysplasia class, 14 (11.4%) in the BE-with-dysplasia class, 21 (17.1%) in the adenocarcinoma class, and 58 (47.2%) in the normal class. Classification accuracies of the proposed model were 0.85 (95% CI, 0.81-0.90) for the BE-no-dysplasia class, 0.89 (95% CI, 0.84-0.92) for the BE-with-dysplasia class, and 0.88 (95% CI, 0.84-0.92) for the adenocarcinoma class. The proposed model achieved a mean accuracy of 0.83 (95% CI, 0.80-0.86) and marginally outperformed the sliding window approach on the same testing set. The F1 scores of the attention-based model were at least 8% higher for each class compared with the sliding window approach: 0.68 (95% CI, 0.61-0.75) vs 0.61 (95% CI, 0.53-0.68) for the normal class, 0.72 (95% CI, 0.63-0.80) vs 0.58 (95% CI, 0.45-0.69) for the BE-no-dysplasia class, 0.30 (95% CI, 0.11-0.48) vs 0.22 (95% CI, 0.11-0.33) for the BE-with-dysplasia class, and 0.67 (95% CI, 0.54-0.77) vs 0.58 (95% CI, 0.44-0.70) for the adenocarcinoma class. However, this outperformance was not statistically significant.

Conclusions and Relevance

Results of this study suggest that the proposed attention-based deep neural network framework for BE and esophageal adenocarcinoma detection is important because it is based solely on tissue-level annotations, unlike existing methods that are based on regions of interest. This new model is expected to open avenues for applying deep learning to digital pathology.

Definition of Barrett Esophagus in the United States: Support for Retention of a Requirement for Goblet Cells

Barrett esophagus (BE) predisposes patients to the development of esophageal adenocarcinoma (EAC). However, the global definition of BE is controversial. Pathologists in Europe and the United States require intestinal metaplasia (IM) within columnar-lined mucosa (CLM) in the tubular esophagus to diagnose BE, whereas in the UK and Japan only the presence of CLM is required. To aid in establishing an appropriate definition for BE, we evaluated whether IM accompanies EAC in a US patient cohort. We examined a series of 139 consecutive patients who underwent endoscopic mucosal resections or esophagectomies for EAC performed at a US tertiary care center. The resection specimens were evaluated for the presence (IM+) or absence (IM-) of IM within CLM. Ninety-seven (70%) patients were IM+. Tumors found in IM- patients tended to be advanced at the time of resection (57% pT3 or greater, IM-; 31% pT3 or greater, IM+; P=0.02) such that the tumor may have "overgrown" zones of IM. We hypothesized that changes as a result of neoadjuvant chemotherapy or radiation might mask preexisting IM. When evaluating this hypothesis, we found that 34 of 39 of treatment-naive patients were IM+. Two of the 5 IM- patients had prior IM+ biopsies resulting in 92% of treatment-naive patients who were IM+. In our US hospital population, CLM with IM in the tubular esophagus is found in association with EAC in 70% to 92% of patients. We believe that based on these data the United States definition of BE should continue to require the presence of IM.

Buried Barrett's Esophagus with High-Grade Dysplasia after Radiofrequency Ablation

Radiofrequency ablation therapy is an effective endoscopic option for the eradication of Barrett’s esophagus that appears to reduce the risk of esophageal cancer. A concern associated with this technique is the development of subsquamous/buried intestinal metaplasia, whose clinical relevance and malignant potential have not yet been fully elucidated. Fewer than 20 cases of subsquamous neoplasia after the successful radiofrequency ablation of Barrett’s esophagus have been reported to date. Here, we describe a new case of subsquamous neoplasia (high-grade dysplasia) following radiofrequency ablation that was managed with endoscopic resection. Our experience suggests that a meticulous endoscopic inspection prior to and after radiofrequency ablation is fundamental to reduce the risk of buried neoplasia development.

LKB1 inactivation occurs in a subset of esophageal adenocarcinomas and is sufficient to drive tumor cell proliferation

BACKGROUND

The incidence of esophageal adenocarcinoma (EAC) has increased over the last several decades. Apart from mutations in TP53 gene, there are little data on genetic drivers of EAC. Liver kinase B1 (LKB1) has emerged as a multifunctional tumor suppressor regulating cell growth, differentiation, and metabolism. Somatic inactivation of LKB1 has been described in several tumor types; however, whether LKB1 inactivation has a role in EAC is unknown. Here we analyzed patient tumors to assess the prevalence of LKB1 loss in EAC.

METHODS

Chromosomal deletion and expression of LKB1 in EAC were investigated using publicly available genomic data. Protein expression was assessed by immunohistochemistry (IHC) analysis for LKB1 in a tissue microarray (TMA) containing esophageal tumor specimens, including EAC. LKB1 was suppressed in EAC cells to determine the effects on cell growth in vitro.

RESULTS

Analysis of EAC data in The Cancer Genome Atlas dataset revealed significant deletion of chromosome 19p13.3, containing the LKB1 gene locus. Single copy loss (shallow deletion) of LKB1 was present in 58% of EAC samples. Expression of LKB1 was significantly lower in EAC tumors compared with normal esophagus. IHC analysis showed reduced LKB1 protein expression in EAC. Suppression of LKB1 was sufficient to enhance EAC cell growth in vitro.

CONCLUSIONS

Our data suggest that inactivation of LKB1 frequently occurs in EAC. Based on the reported oncogenic effects of LKB1 inactivation, our data indicate that LKB1 loss may play a significant role in EAC tumorigenesis, and point to the need for future studies.

Does physical activity protect against the development of gastroesophageal reflux disease, Barrett's esophagus, and esophageal adenocarcinoma? A review of the literature with a meta-analysis

Physical activity affects the functioning of the gastrointestinal system through both local and systemic effects and may play an important role in reducing the risk of esophageal adenocarcinoma. This review assesses the biological mechanisms and epidemiological evidence for the relationship between physical activity and the development of esophageal adenocarcinoma and its precursor diseases: gastroesophageal reflux disease (GORD) and Barrett's esophagus. A search of PubMed, Medline, Embase, and CINAHL was conducted from their inceptions to 25th March 2017 for analytical studies that examined associations between recreational and/or occupational levels of physical activity and the risk of GORD, Barrett's esophagus, and esophageal adenocarcinoma. Where appropriate, a meta-analysis of effects was undertaken. Seven studies were included (2 cohort, 5 case control). For GORD, there were three case-control studies with 10 200 cases among 78 034 participants, with a pooled estimated OR of 0.67 (95% CI 0.57-0.78) for high versus low levels of recreational physical activity. In Barrett's esophagus, there was a single case-control study, which reported no association, OR 1.19 (95% CI 0.82-1.73). For esophageal adenocarcinoma, there were three studies (two prospective cohort, one case control) with 666 cases among 910 376 participants. The largest cohort study reported an inverse association for high versus low levels of recreational physical activity, RR 0.68, 95% CI 0.48-0.96. The remaining two studies reported no associations with either occupational or combined recreational and occupational activity. Heterogeneity in the measurement of exposure (recreational, occupational, and both) made a pooled estimate for esophageal adenocarcinoma inappropriate. Although limited, there is some evidence that higher levels of recreational physical activity may reduce the risk of both GORD and esophageal adenocarcinoma, but further large cohort studies examining the type, intensity and duration of activities that may be beneficial are needed.

Obesity-associated digestive cancers: A review of mechanisms and interventions

The prevalence of obesity has steadily increased over the past few decades. Previous studies suggest that obesity is an oncogenic factor and that over 20% of all cancers are obesity-related. Among such cancers, digestive system malignancies (including esophageal adenocarcinomas, colorectal cancers, and cancers of the gastric cardia, liver, and pancreas) are reported most frequently. While the 5-year survival rates of cancers of the breast and prostate are 90%, that rate is only 45% for digestive cancers. In this review, the mechanisms of obesity-associated digestive cancers are discussed, with an emphasis on obesity-related gene mutations, insulin and insulin-like growth factor signaling pathways, chronic inflammation, and altered adipokine levels. Evidence that these factors often function interdependently rather than independently in carcinogenesis is presented. Recommended interventions that may reduce the burden of obesity-associated digestive cancers, such as participation in physical activity, diet modulation, and calorie restriction, are also described.

Advances in the Endoscopic Diagnosis of Barrett Esophagus

BACKGROUND

Barrett esophagus (BE) continues to be a major risk factor for developing esophageal adenocarcinoma.

METHODS

We review the risk factors, diagnosis, and management of BE, with an emphasis on the most current endoscopic diagnostic modalities for BE.

RESULTS

Novel diagnostic modalities have emerged to address the inadequacies of standard, untargeted biopsies, such as dye-based and virtual chromoendoscopy, endoscopic mucosal resection, molecular biomarkers, optical coherence tomography, confocal laser endomicroscopy, volumetric laser endomicroscopy, and endocytoscopy. Treatment of BE depends on the presence of intramucosal cancer or dysplasia, particularly high-grade dysplasia with or without visible mucosal lesions.

CONCLUSIONS

Recent advances in endoscopic diagnostic tools demonstrate promising results and help to mitigate the shortcomings of the Seattle protocol. Future research as well as refining these tools may help aid them in replacing standard untargeted biopsies.

Acetylsalicylic Acid Exhibits Antitumor Effects in Esophageal Adenocarcinoma Cells In Vitro and In Vivo

BACKGROUND AND AIM

Recent observational studies have shown therapeutic benefits of acetylsalicylic acid (ASA) in several types of cancer. We examined whether ASA exerts antitumor activity in esophageal adenocarcinoma (EAC).

METHODS

Human EAC cells (OE33) were treated with ASA (0-5 mM) to evaluate proliferation, apoptosis, and migration. In vivo model: OE33-derived tumors were subcutaneously implanted into athymic mice which were allocated to ASA (5 or 50 mg/kg/day)/vehicle (5-6 animals/group). Tumor growth was assessed every 2-3 days, and after 40 days, mice were euthanized. Plasma drug levels were determined by high-performance liquid chromatography. Histological and immunohistochemical (Ki67, activated caspase-3) analysis of tumors were performed. The effect of ASA on tumor prostaglandin E2 (PGE2) levels was also evaluated.

RESULTS

In vitro cell proliferation and migration were significantly inhibited while apoptosis increased (p < 0.05) by ASA. Although ASA did not induce tumor remission, tumor progression was significantly lower in ASA-treated mice when compared to non-treated animals (478 % in mice treated with 5 mg/kg/day ASA vs. 2696 % control; 748 % in mice treated with 50 mg/kg/day ASA vs. 2670 % control). Maximum tumor inhibition was 92 and 85 %, respectively. This effect was associated with a significant decrease of proliferation index in tumors. ASA 5 mg/kg/day did not modify tumor PGE2 levels. Whereas tumor PGE2 content in mice treated with ASA 50 mg/kg was lower than in control mice, the difference was not significant.

CONCLUSION

Although these results need to be confirmed in other EAC cells, our data suggest a role for ASA in the treatment of this tumor.

A meta-analysis of confocal laser endomicroscopy for the detection of neoplasia in patients with Barrett's esophagus

BACKGROUND AND AIMS

Barrett's esophagus (BE) is considered the most important risk factor for development of esophageal adenocarcinoma. Confocal laser endomicroscopy (CLE) is a recently developed technique used to diagnose neoplasia in BE. This meta-analysis was performed to assess the accuracy of CLE for diagnosis of neoplasia in BE.

METHODS

We searched EMBASE, PubMed, Cochrane Library, and Web of Science to identify relevant studies for all articles published up to June 27, 2015 in English. The quality of included studies was assessed using QUADAS-2. Per-patient and per-lesion pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio with 95% confidence intervals (CIs) were calculated.

RESULTS

In total, 14 studies were included in the final analysis, covering 789 patients with 4047 lesions. Seven studies were included in the per-patient analysis. Pooled sensitivity and specificity were 89% (95% CI: 0.82-0.94) and 83% (95% CI: 0.78-0.86), respectively. Ten studies were included in the per-lesion analysis. Compared with the PP analysis, the corresponding pooled sensitivity declined to 77% (95% CI: 0.73-0.81) and specificity increased to 89% (95% CI: 0.87-0.90). Subgroup analysis showed that probe-based CLE (pCLE) was superior to endoscope-based CLE (eCLE) in pooled specificity [91.4% (95% CI: 89.7-92.9) vs 86.1% (95% CI: 84.3-87.8)] and AUC for the sROC (0.885 vs 0.762).

CONCLUSION

Confocal laser endomicroscopy is a valid method to accurately differentiate neoplasms from non-neoplasms in BE. It can be applied to BE surveillance and early diagnosis of esophageal adenocarcinoma.

Acetic acid chromoendoscopy for the diagnosis of early neoplasia and specialized intestinal metaplasia in Barrett's esophagus: a meta-analysis

BACKGROUND AND AIMS

Barrett's esophagus (BE) surveillance with random biopsies is time-consuming, invasive, and can lead to sampling error. Acetic acid chromoendoscopy (AAC) with targeted biopsies has been proposed as an effective alternative. The aim of this study was to assess the diagnostic accuracy of AAC for the detection of early neoplasia (high-grade dysplasia [HGD] or early cancer [EC]) and specialized intestinal metaplasia (SIM) in patients with BE.

METHODS

We performed a meta-analysis of all primary studies that compared AAC-based diagnoses (index test) with histopathology as the reference standard. The data were extracted on a per-patient, per-area, and per-procedure basis whenever available.

RESULTS

Thirteen prospective studies met the inclusion criteria. For the diagnosis of HGD/EC, the pooled sensitivity, specificity, positive likelihood ratio (LR+), and negative likelihood ratio (LR-) for all included studies (9 studies, 1379 patients) were 0.92 (95% confidence interval [CI], 0.83-0.97), 0.96 (95% CI, 0.85-0.99), 25.0 (95% CI, 5.9-105.3), and 0.08 (95% CI, 0.04-0.18), respectively. Results were not significantly different when considering only studies with a per-patient analysis. For the characterization of SIM, the pooled sensitivity, specificity, LR+, and LR- for all the included studies (8 studies, 516 patients) were 0.96 (95% CI, 0.83-0.99), 0.69 (95% CI, 0.54-0.81), 3.0 (95% CI, 2.0-4.7), and 0.06 (95% CI, 0.01-0.26), respectively. No significant sources of heterogeneity were identified on subgroup analysis.

CONCLUSION

AAC has an overall high diagnostic accuracy for detecting HGD/EC in patients with BE. For SIM characterization, AAC sensitivity is very high but has poor specificity, suggesting that histological confirmation is necessary when AAC is positive.

The feasibility of an exercise intervention in males at risk of oesophageal adenocarcinoma: a randomized controlled trial

Objective

To investigate the feasibility and safety of a 24-week exercise intervention, compared to control, in males with Barrett’s oesophagus, and to estimate the effect of the intervention, compared to control, on risk factors associated with oesophageal adenocarcinoma development.

Methods

A randomized controlled trial of an exercise intervention (60 minutes moderate-intensity aerobic and resistance exercise five days/week over 24 weeks; one supervised and four unsupervised sessions) versus attention control (45 minutes stretching five days/week over 24 weeks; one supervised and four unsupervised sessions) in inactive, overweight/obese (25.0–34.9 kg/m²) males with Barrett’s oesophagus, aged 18–70 years. Primary outcomes were obesity-associated hormones relevant to oesophageal adenocarcinoma risk (circulating concentrations of leptin, adiponectin, interleukin-6, tumour necrosis factor-alpha, C-reactive protein, and insulin resistance [HOMA]). Secondary outcomes included waist circumference, body composition, fitness, strength and gastro-oesophageal reflux symptoms. Outcomes were measured at baseline and 24-weeks. Intervention effects were analysed using generalised linear models, adjusting for baseline value.

Results

Recruitment was difficult in this population with a total of 33 participants recruited (target sample size: n = 80); 97% retention at 24-weeks. Adherence to the exercise protocol was moderate. No serious adverse events were reported. A statistically significant intervention effect (exercise minus control) was observed for waist circumference (-4.5 [95% CI -7.5, -1.4] cm; p < 0.01). Effects on primary outcomes were not statistically significant.

Conclusion

This small, exploratory trial provides important information to inform future trial development including recruitment rates and estimates of effect sizes on outcomes related to oesophageal adenocarcinoma risk. Future trials should investigate a combined dietary and exercise intervention to achieve greater weight loss in this population and relax inclusion criteria to maximize recruitment.

Trial Registration

Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12609000401257

Achalasia: a risk factor that must not be forgotten for esophageal squamous cell carcinoma

Alcohol and tobacco abuse are the main risk factors for esophageal squamous cell carcinoma (ESCC), but other conditions that induce chronic irritation of the esophageal mucosa have also been attributed to it. For example, long-standing achalasia increases 16 times the risk of developing ESCC. We report the case of a patient with long-standing achalasia who developed ESCC. Although this complication is infrequent, it should be remembered by clinicians who treat patients with achalasia to detect early stages cancer.

Evaluation of Barrett esophagus by multiphoton microscopy

CONTEXT

Multiphoton microscopy (MPM) based on 2-photon excitation fluorescence and second-harmonic generation allows simultaneous visualization of cellular details and extracellular matrix components of fresh, unfixed, and unstained tissue. Portable multiphoton microscopes, which could be placed in endoscopy suites, and multiphoton endomicroscopes are in development, but their clinical utility is unknown.

OBJECTIVE

To examine fresh, unfixed endoscopic biopsies obtained from the distal esophagus and gastroesophageal junction to (1) define the MPM characteristics of normal esophageal squamous mucosa and gastric columnar mucosa, and (2) evaluate whether diagnosis of intestinal metaplasia/Barrett esophagus (BE) could be made reliably with MPM.

DESIGN

The study examined 35 untreated, fresh biopsy specimens from 25 patients who underwent routine upper endoscopy. A Zeiss LSM 710 Duo microscope (Carl Zeiss, Thornwood, New York) coupled to a Spectra-Physics (Mountain View, California) Tsunami Ti:sapphire laser was used to obtain a MPM image within 4 hours of fresh specimen collection. After obtaining MPM images, the biopsy specimens were placed in 10% buffered formalin and submitted for routine histopathologic examination. Then, the MPM images were compared with the findings in the hematoxylin-eosin-stained, formalin-fixed, paraffin-embedded sections. The MPM characteristics of the squamous, gastric-type columnar and intestinal-type columnar epithelium were analyzed. In biopsies with discrepancy between MPM imaging and hematoxylin-eosin-stained sections, the entire tissue block was serially sectioned and reevaluated. A diagnosis of BE was made when endoscopic and histologic criteria were satisfied.

RESULTS

Based on effective 2-photon excitation fluorescence of cellular reduced pyridine nucleotides and flavin adenine dinucleotide and lack of 2-photon excitation fluorescence of mucin and cellular nuclei, MPM could readily identify and distinguish among squamous epithelial cells, goblet cells, gastric foveolar-type mucous cells, and parietal cells in the area of gastroesophageal junction. Based on the cell types identified, the mucosa was defined as squamous, columnar gastric type (cardia/fundic-type), and metaplastic columnar intestinal-type/BE. Various types of mucosa seen in the study of 35 biopsies included normal squamous mucosa only (n = 14; 40%), gastric cardia-type mucosa only (n = 2; 6%), gastric fundic mucosa (n = 6; 17%), and both squamous and gastric mucosa (n = 13; 37%). Intestinal metaplasia was identified by the presence of goblet cells in 10 of 25 cases (40%) leading to a diagnosis of BE on MPM imaging and only in 7 cases (28%) by histopathology. In 3 of 35 biopsies (9%), clear-cut goblet cells were seen by MPM imaging but not by histopathology, even after the entire tissue block was sectioned. Based on effective 2-photon excitation fluorescence of elastin and second-harmonic generation of collagen, connective tissue in the lamina propria and the basement membrane was also visualized with MPM.

CONCLUSIONS

Multiphoton microscopy has the ability to accurately distinguish squamous epithelium and different cellular elements of the columnar mucosa obtained from biopsies around the gastroesophageal junction, including goblet cells that are important for the diagnosis of BE. Thus, use of MPM in the endoscopy suite might provide immediate microscopic images during endoscopy, improving screening and surveillance of patients with BE.

Utility of confocal laser endomicroscopy in identifying high-grade dysplasia and adenocarcinoma in Barrett's esophagus: a systematic review and meta-analysis

Confocal laser endomicroscopy (CLE) is a novel endoscopic technique that has emerged as an important tool in the in-vivo visualization and detailed assessment of the mucosal layer and subcellular structures in Barrett's esophagus. Current guidelines recommend four-quadrant random biopsies for identification of high-grade dysplasia (HGD) in Barrett's esophagus. However, random biopsies are associated with sampling error and inconsistent histopathologic interpretation. CLE, by providing targeted biopsies, could decrease the sampling error and increase the yield of detection of HGD/adenocarcinoma [esophageal adenocarcinoma (EAC)]. We carried out a meta-analysis to evaluate the diagnostic accuracy of the CLE-based targeted biopsies in detecting HGD/adenocarcinoma compared with four-quadrant random biopsies. A search using medical subject headings (MeSH) terms and keywords was performed in the MEDLINE and Cochrane review databases and relevant studies were identified. All the studies that compared the diagnostic yield from CLE-based targeted biopsies to detect HGD/adenocarcinoma with a gold standard of histopathology were included and a meta-analysis was carried out to estimate the pooled sensitivity, specificity, and positive and negative likelihood ratios using Meta-Disc software. There were a total of seven studies with 345 patients and 3080 lesions that were finally included in the meta-analysis. All the studies had reported per-lesion analyses; however, only four of the seven studies had data reported on per-patient analyses. 'Per-lesion' analysis for the diagnosis of HGD/adenocarcinoma yielded a pooled sensitivity and specificity of 68% [95% confidence interval (CI) of 64-73%] and 88% (95% CI of 87-89%), respectively. The pooled positive and negative likelihood ratios were 6.56 (95% CI of 3.61-11.90) and 0.24 (95% CI of 0.09-0.63), respectively. Similar numbers were calculated on the basis of 'per-patient' basis, which showed a pooled sensitivity and specificity of 86% (95% CI of 74-96%) and 83% (95% CI of 77-88%), respectively. The pooled positive and negative likelihood ratios were 5.61 (95% CI of 2.00-15.69) and 0.21 (95% CI of 0.08-0.59), respectively. CLE, by providing targeted biopsies, has a good diagnostic accuracy in identifying HGD/EAC; however, the overall prevalence of HGD/EAC in the studies included was much higher than what would be seen in clinical practice and these results should be interpreted with caution. Because of its relatively low sensitivity and negative predictive value, CLE may currently not replace standard biopsy techniques for the diagnosis of HGD/EAC in Barrett's esophagus.

Immunohistochemical features of the gastrointestinal tract tumors

Gastrointestinal tract tumors include a wide variety of vastly different tumors and on a whole are one of the most common malignancies in western countries. These tumors often present at late stages as distant metastases which are then biopsied and may be difficult to differentiate without the aid of immunohistochemical stains. With the exception of pancreatic and biliary tumors where there are no distinct immunohistochemical patterns, most gastrointestinal tumors can be differentiated by their unique immunohistochemical profile. As the size of biopsies decrease, the role of immunohistochemical stains will become even more important in determining the origin and differentiation of gastrointestinal tract tumors.

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.).

Preferential up-regulation of heparanase and cyclooxygenase-2 in carcinogenesis of Barrett's oesophagus and intestinal-type gastric carcinoma

AIMS

Metaplastic changes secondary to chronic inflammation at the gastro-oesophageal junction and at the pyloric antrum are recognized as the premalignant conditions of Barrett's oesophageal adenocarcinoma and intestinal-type gastric carcinoma (GC), respectively. Heparanase (HPSE) and cyclooxygenase (COX)-2 have been proved to play critical roles in inflammation as well as in cancer. The aim was to examine the meaning of their expression in inflammation-related carcinogenesis.

METHODS AND RESULTS

First, expression of HPSE and COX-2 in 78 clinical tissues of Barrett's oesophagus was examined by immunohistochemistry and in situ hybridization. Their expression was increased during the metaplasia-dysplasia sequence with increased neovascularization. Successively, their expression in Barrett's dysplasia was compared with that of GC (22 cases of diffuse-type and 10 of intestinal-type). Interestingly, the expression pattern in Barrett's dysplasia was similar to that in intestinal-type GC, which mainly arises from chronic inflammation. Furthermore, cultured cell lines isolated from differentiated GC tissues, which are often found to be of intestinal-type, revealed up-regulated mRNA expression of HPSE and COX-2.

CONCLUSIONS

HPSE and COX-2 are preferentially up-regulated in Barrett's oesophagus and intestinal-type GC. These molecules may play an important role during the development of inflammation-related adenocarcinoma of the upper gastrointestinal tract.

The pathogenesis of Barrett's metaplasia and the progression to esophageal adenocarcinoma

The most important risk factor for the development of Barrett's esophagus is the reflux of both gastric and duodenal contents into the esophagus. The reason why Barrett's metaplasia develops only in a minority of patients suffering from gastroesophageal reflux disease remains unknown.The exact mechanism behind the transition of normal squamous epithelium into specialized columnar epithelium is also unclear. It is likely that stem cells are involved in this metaplastic change, as they are the only permanent residents of the epithelium. Several tumorigenic steps that lead to the underlying genetic instability, which is indispensable in the progression from columnar metaplasia to esophageal adenocarcinoma have been described. This review outlines the process of pathogenesis of Barrett's metaplasia and its progression to esophageal adenocarcinoma.

Era of Barrett’s surveillance: Does equipment matter?

Barrett’s esophagus is a consequence of long standing gastro-esophageal reflux disease and predisposes to the development of esophageal adenocarcinoma. Regular surveillance endoscopies can detect curable early neoplasia in asymptomatic patients, which in turn could improve the prognosis compared to symptomatic cancer. Early neoplastic lesions, which are amenable for local therapy, could be treated endoscopically, avoiding a major surgery. However, in the absence of obvious mucosal lesions, random four quadrant biopsies are done, which is associated with significant sampling error. Newer imaging modalities, such as autofluorescence endoscopy, are helpful in detecting subtle lesions that could be examined in detail with narrow band imaging to characterize and target biopsies. This has the potential benefit of reducing the number of random biopsies with a better yield of dysplasia. Confocal endomicroscopy provides “optical biopsies” and is a valuable tool in targeting biopsies to improve dysplasia detection; however, this is technically challenging. Fuji intelligent chromoendoscopy and I-Scan are recent additions to the imaging armamentarium that have produced notable early results. While all these additional new imaging techniques are promising, a thorough examination by high resolution white light endoscopy after clearing the mucosa with mucolytics should be the minimum standard to improve dysplasia detection during Barrett’s surveillance.

Mucosal dendritic cell diversity in the gastrointestinal tract

The discovery of dendritic cells (DCs) in skin by Paul Langerhans in 1868 identified a cell type which has since been recognized as a key link between innate and adaptive immunity. DCs originate from bone marrow and disseminate through blood to all tissues in the body, and distinct DC subpopulations have been identified in many different tissues. DC diversity is apparent throughout all mucosal surfaces of the body, but the focus of this review article is DC diversity throughout the gastro-intestinal tract (GIT). DC subpopulations have been well characterized in the oral cavity and small intestine, but DC characterization in other regions, such as the esophagus and stomach, is limited. Substantial research has focused on DC function during disease, but understanding the regulation of inflammation and the induction of acquired immune responses requires combined phenotypic and functional characterization of individual DC subpopulations. Furthermore, little is known regarding mucosal DC subpopulations in the GIT of the neonate and how these DC populations change following colonization by commensal microflora. The current review will highlight mucosal DC diversity and discuss factors that may influence mucosal DC differentiation.

Cryotherapy in the management of esophageal dysplasia and malignancy

Accumulating evidence highlights the promising results seen with endoscopic spray cryotherapy in the treatment of dysplasia associated with Barrett esophagus and esophageal carcinoma. Published studies show that the success of spray cryotherapy to eradicate Barrett high-grade dysplasia is comparable to that for other therapies, with a favourable safety profile and high levels of patient comfort. For patients with untreatable esophageal cancer, spray cryotherapy offers a therapeutic option with the potential for complete eradication in early-stage disease and palliation in advanced cases. The mechanism of tissue injury in cryotherapy is unique, with direct cytotoxic effects and ischemic effects from vascular injury. Increased tumor cell death through induction of apoptosis and immunologic effects require further study.

Acid-related disorders in the elderly

Diseases of the upper gastrointestinal tract such as gastroesophageal reflux disease (GERD), peptic ulcer and gastric cancer become more common and more severe with advancing age. Older individuals also tend to have a higher prevalence of co-morbid factors, such as Helicobacter pylori infection, presence of other diseases, or use of medications (e.g., nonsteroidal anti-inflammatory drugs, bisphosphonates) that increase their risk for acid-related disorders. Unfortunately, in the elderly patient with these disorders symptom presentation may be slight or atypical, resulting in a delayed diagnosis. In general, the treatment of older individuals with peptic ulcer or GERD and its complications is similar to that of younger individuals. Proton pump inhibitors are the basis of therapy for symptom relief, healing of erosive esophagitis and peptic ulceration, reduction of the risk for NSAID induced mucosal damage, and prevention of disease relapses. The strongest prevalence of H.pylori infection in the elderly, as well as the role of H.pylori in the occurrence of gastric lesions, in particular ulcer diseases, gastric precancerous lesions and gastric cancer, make the diagnosis and the eradication of H.pylori in this population of the utmost importance. Strategies to improve the management of upper gastrointestinal diseases in older people will reduce mortality and improve quality of life.

Management of Barrett's oesophagus

Barrett's oesophagus, which is thought to be a consequence of gastro-oesophageal reflux disease (GORD), is a well-recognized precursor of oesophageal adenocarcinoma. Medical therapies and anti-reflux surgeries for GORD have shown conflicting results regarding the progression of Barrett's metaplasia to neoplasia. After high-grade dysplasia or intramucosal cancer is identified, it has been standard practice to conduct an oesophagectomy, despite this having an associated risk of morbidity and mortality. In recent years however, endoscopic therapy has become a viable alternative to oesophagectomy in treating early neoplasia.

Squamous overgrowth is not a safety concern for photodynamic therapy for Barrett's esophagus with high-grade dysplasia

BACKGROUND & AIMS

Photodynamic therapy with porfimer sodium combined with acid suppression (PHOPDT) is used to treat patients with Barrett's esophagus (BE) with high-grade dysplasia (HGD). A 5-year phase 3 trial was conducted to determine the extent of squamous overgrowth of BE with HGD after PHOPDT.

METHODS

Squamous overgrowth was compared in patients with BE with HGD randomly assigned (2:1) to receive PHOPDT (n=138) or 20 mg omeprazole twice daily (n=70). Patients underwent 4-quadrant jumbo esophageal biopsies every 2 cm throughout the pretreatment length of BE until 4 consecutive quarterly follow-up results were negative for HGD and then biannually up to 5 years or treatment failure. Endoscopies were reviewed by blinded gastroenterology pathologists.

RESULTS

Histologic assessment of 33,658 biopsies showed no significant difference (P> .05) in squamous overgrowth between groups when compared per patient (30% vs 33%) or per biopsy (0.5% vs 1.3%), or when the average number of biopsies with squamous overgrowth were compared per patient (0.48 vs 0.66). The highest grade of neoplasia per endoscopy was not found exclusively beneath squamous mucosa in any patient.

CONCLUSIONS

No difference was observed in squamous overgrowth between patients given PHOPDT plus omeprazole compared with only omeprazole. Squamous overgrowth did not obscure the most advanced neoplasia in any patient. Treatment of HGD with PHOPDT in patients with BE does not present a long-term risk of failure to detect subsquamous dysplasia or carcinoma.

The incidence of esophageal cancer and high-grade dysplasia in Barrett's esophagus: a systematic review and meta-analysis

Barrett's esophagus is a well-recognized precursor of esophageal adenocarcinoma. Surveillance of Barrett's esophagus patients is recommended to detect high-grade dysplasia (HGD) or early cancer. Because of wide variation in the published cancer incidence in Barrett's esophagus, the authors undertook a systematic review and meta-analysis of cancer and HGD incidence in Barrett's esophagus. Ovid Medline (Ovid Technologies, Inc., New York, New York) and EMBASE (Elsevier, Amsterdam, the Netherlands) databases were searched for papers published between 1950 and 2006 that reported the cancer/HGD risk in Barrett's esophagus. Where possible, early incident cancers/HGD were excluded, as were patients with HGD at baseline. Forty-seven studies were included in the main analysis, and the pooled estimate for cancer incidence in Barrett's esophagus was 6.1/1,000 person-years, 5.3/1,000 person-years when early incident cancers were excluded, and 4.1/1,000 person-years when both early incident cancer and HGD at baseline were excluded. Corresponding figures for combined HGD/cancer incidence were 10.0 person-years, 9.3 person-years, and 9.1/1,000 person-years. Compared with women, men progressed to cancer at twice the rate. Cancer or HGD/cancer incidences were lower when only high-quality studies were analyzed (3.9/1,000 person-years and 7.7/1,000 person-years, respectively). The pooled estimates of cancer and HGD incidence were low, suggesting that the cost-effectiveness of surveillance is questionable unless it can be targeted to those with the highest cancer risk.

Cyclooxygenase-2 and inducible nitric oxide synthase gene polymorphisms and risk of reflux esophagitis, Barrett's esophagus, and esophageal adenocarcinoma

The incidence of esophageal adenocarcinoma has increased in recent years, and Barrett's esophagus is a recognized risk factor. Gastroesophageal reflux of acid and/or bile is linked to these conditions and to reflux esophagitis. Inflammatory disorders can lead to carcinogenesis through activation of "prosurvival genes," including cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). Increased expression of these enzymes has been found in esophageal adenocarcinoma, Barrett's esophagus, and reflux esophagitis. Polymorphic variants in COX-2 and iNOS genes may be modifiers of risk of these conditions. In a population-based case-control study, we examined associations of the COX-2 8473 T>C and iNOS Ser(608) Leu (C>T) polymorphisms with risk of esophageal adenocarcinoma, Barrett's esophagus, and reflux esophagitis. Genomic DNA was extracted from blood samples collected from cases of esophageal adenocarcinoma (n = 210), Barrett's esophagus (n = 212), and reflux esophagitis (n = 230) and normal population controls frequency matched for age and sex (n = 248). Polymorphisms were genotyped using TaqMan allelic discrimination assays. Odds ratios and 95% confidence intervals were obtained from logistic regression models adjusted for potential confounding factors. The presence of at least one COX-2 8473 C allele was associated with a significantly increased risk of esophageal adenocarcinoma (adjusted odds ratio, 1.58; 95% confidence interval, 1.04-2.40). There was no significant association between this polymorphism and risk of Barrett's esophagus or reflux esophagitis or between the iNOS Ser 608 Leu polymorphism and risk of these esophageal conditions. Our study suggests that the COX-2 8473 C allele is a potential genetic marker for susceptibility to esophageal adenocarcinoma.

Incidence of esophageal adenocarcinoma in patients with Barrett's esophagus and high-grade dysplasia: a meta-analysis

BACKGROUND

Patients with Barrett's esophagus (BE) and high-grade dysplasia (HGD) are at a high risk for developing esophageal adenocarcinoma. However, the reported rate of cancer development in patients with HGD who were undergoing surveillance has varied among published studies.

OBJECTIVE

To determine an overall precise estimate of cancer incidence in patients with HGD who were undergoing surveillance endoscopy.

DESIGN

Systematic review and meta-analysis.

METHODS

We conducted a systematic search of the published literature and selected original articles that examined patients with histologically proven BE and HGD, patients who had not undergone endoscopic ablation or surgical therapy, patients with 6 months' follow-up, no esophageal cancer at the time of enrollment or within 6 months, and studies in which follow-up was reported in person-time. Two investigators independently conducted the search and abstraction.

MAIN OUTCOME MEASUREMENT

The weighted mean event rate was calculated and expressed as the weighted incidence rate, and its CIs were calculated.

RESULTS

The search yielded 4 articles that met the inclusion criteria, and these were analyzed. A total of 236 patients with HGD were followed for 1241 patient-years, and esophageal adenocarcinoma was reported in 69 patients, providing a crude incidence rate of 5.57 per 100 patient-years. The weighted incidence rate was 6.58 per 100 patient-years (95% CI, 4.97-8.19).

LIMITATIONS

A small number of studies that met inclusion criteria.

CONCLUSIONS

In patients with BE and with HGD who were undergoing surveillance, esophageal adenocarcinoma develops in approximately 6 per 100 patient-years during the first few years of follow-up. These data may better inform physicians and patients in management decisions.

Columnar lined (Barrett's) esophagus: future perspectives

Columnar lined esophagus (CLE) or Barrett's esophagus is the precursor for esophageal adenocarcinoma. Future advances in understanding and management of this condition as well as improving the quality of care of CLE patients depends on answering essential questions. It is important to standardize the criteria for CLE definition. The rapid increase in incidence of CLE and adenocarcinoma raises serious concerns that the current management of gastroesophageal reflux disease (GERD) needs reassessment. The risk factors that determine who will and will not develop CLE are as yet undetermined. There is a need to develop a clinical risk stratification tool, which will help in determining who should be screened. The impact of elimination of GERD on the natural history of CLE is one important area for future research. The benefit of surveillance strategies remains unproven and the ideal endoscopic frequency, protocols and markers of cancer risk are unknown. Dysplasia may not provide the gold standard marker of cancer risk because of some inherited problems. A better technique than the current endoscopic pinch biopsy protocol is needed. To overcome the limitations of histological markers, many other markers of cancer risk needs to be developed and validated. The key question as to whether cancer risk is actually reduced by the new ablation modalities remains unanswered. The natural history of dysplasia and its management needs to be clarified. Although many questions have to be answered, it seems, however, that at least some answers exist, and these and proposals for answering some of these questions are underlined throughout this review.

Multicentric Adenocarcinomas in a Long-Segment of Barrett's Esophagus

This report describes a complicated course of a 58-year-old patient with multicentric Barrett's carcinoma within a long-segment of Barrett metaplasia. After abdominal-thoracic resection of the cancer, with incomplete removal of the long-segment metaplastic lesion, invasive carcinoma was diagnosed in the remnant Barrett's segment. Endoscopic mucosal resection was done, but Barrett's mucosa was left in situ again. Recurrent tumor growth was diagnosed only few months later. Finally, transthoracic complete resection on the remnant Barrett's segment was performed. Thus, our case demonstrates impressively the appearance of multicentric adenocarcinomas in Barrett's esophagus and underlines the necessity of resection of the complete Barrett mucosa.

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.

Characteristics of patients with columnar-lined Barrett’s esophagus and risk factors for progression to esophageal adenocarcinoma

AIM: To determine the risk factors for the development of esophageal adenocarcinoma in these patients with columnar-lined esophagus (CLE).

METHODS: Data collected retrospectively on 597 consecutive patients diagnosed at endoscopy and histology to have CLE at Leeds General Infirmary between 1984 and 1995 were analyzed. Factors evaluated included age, sex, length of columnar segment, smoking, and drinking habits, history of non-steroidal ingestion, presence of endoscopic esophagitis, ulceration or benign strictures and presence of Helicobacter pylori in esophageal biopsies. Univariate and multivariate analyses were performed to identify risk factors for the development of adenocarcinoma.

RESULTS: Forty-four patients presented or developed esophageal adenocarcinoma during follow-up. Independent risk factors for the development of adenocarcinoma in patients with CLE were males (OR 5.12, 95%CI 2.04-12.84, P = 0.0005), and benign esophageal stricture (OR 4.37, 95%CI 2.02-9.45, P = 0.0002). Male subjects and patients who developed benign esophageal stricture constituted 86% (n = 38) of all patients who presented or developed esophageal adenocarcinoma. The presence of esophagitis was associated with a significant reduction in the development of esophageal carcinoma (OR 0.28, 95%CI 0.13-0.57, P = 0.0006). No other clinical characteristics differentiate between the non-malignant and malignant group.

CONCLUSION: In patients with CLE, endoscopic surveillance for the early detection of adenocarcinoma may be restricted to male subjects, as well as patients who develop benign esophageal strictures.

Increased Barrett's esophagus for the decade between 1991 and 2000 at a single university medical center

Barrett's esophagus is being diagnosed increasingly in the United States. The aim of this study was to determine whether the increased diagnosis of Barrett's esophagus is due to endoscopic reporting and/or a truly increasing rate. This retrospective study reviewed 18,183 endoscopy reports at Temple University Hospital from January 1991 through December 2000. Annual rates of new cases of endoscopically suspected Barrett's esophagus were determined. Biopsy results were reviewed for the diagnosis of Barrett's esophagus (i.e., specialized intestinal metaplasia). Rates of Barrett's esophagus increased from 3.22 to 8.28 per 100 endoscopies (257%; P < 0.01) on endoscopy and from 0.67 to 2.76 per 100 endoscopies (412%; P < 0.01) on histology from 1991 to 2000. Twenty-four and seven-tenths percent (252/1020) of patients suspected at endoscopy to have Barrett's esophagus were confirmed by histology. This study demonstrates an increasing rate of new cases of suspected Barrett's esophagus on endoscopy and confirmed Barrett's esophagus on histology over the last decade. The endoscopic impression of Barrett's esophagus was about four times higher than the confirmed diagnosis of Barrett's esophagus (intestinal metaplasia) on histology.

Photodynamic therapy with porfimer sodium for ablation of high-grade dysplasia in Barrett's esophagus: international, partially blinded, randomized phase III trial

BACKGROUND

Barrett's esophagus (BE) may lead to high-grade dysplasia (HGD) and adenocarcinoma. The objective was to examine the impact of treating patients with BE and with HGD by using porfimer sodium (POR) and photodynamic therapy (PDT) for ablating HGD and reducing the incidence of esophageal adenocarcinoma.

METHODS

The design was a multicenter, partially blinded (pathology), randomized clinical trial conducted in patients with BE who have HGD. There were 30 contributing centers. A total of 485 patients were screened, with 208 in the intent-to-treat population and 202 in the safety population. Patients were randomized on a 2:1 basis to compare PDT with POR plus omeprazole (PORPDT) with omeprazole only (OM). The main outcome measurement was complete HGD ablation occurring at any time during the study period.

RESULTS

There was a significant difference (p < 0.0001) in favor of PORPDT (106/138 [77%]) compared with OM (27/70 [39%]) in complete ablation of HGD at any time during the study period. The occurrence of adenocarcinoma in the PORPDT group (13%) (n=18) was significantly lower (p < 0.006) compared with the OM group (28%) [corrected] (n=20). The safety profile showed 94% of patients in the PORPDT group and 13% of patients in the OM group had treatment-related adverse effects. The limitations of the study were that PDT therapy may have had to be applied more than once and that patients spent more time in treatment. The patients and the physicians were not blinded to the treatment.

CONCLUSIONS

PORPDT in conjunction with omeprazole is an effective therapy for ablating HGD in patients with BE and in reducing the incidence of esophageal adenocarcinoma.

Progression of Barrett's metaplasia to adenocarcinoma is associated with the suppression of the transcriptional programs of epidermal differentiation

We did expressional profiling on 24 paired samples of normal esophageal epithelium, Barrett's metaplasia, and esophageal adenocarcinomas. Matching tissue samples representing the three different histologic types were obtained from each patient undergoing esophagectomy for adenocarcinoma. Our analysis compared the molecular changes accompanying the transformation of normal squamous epithelium with Barrett's esophagus and adenocarcinoma in individual patients rather than in a random cohort. We tested the hypothesis that expressional profiling may reveal gene sets that can be used as molecular markers of progression from normal esophageal epithelium to Barrett's esophagus and adenocarcinoma. Expressional profiling was done using U133A GeneChip (Affymetrix), which represent approximately two thirds of the human genome. The final selection of 214 genes permitted the discrimination of differential gene expression of normal esophageal squamous epithelium, Barrett's esophagus, and adenocarcinoma using two-dimensional hierarchical clustering of selected genes. These data indicate that transformation of Barrett's esophagus to adenocarcinoma is associated with suppression of the genes involved in epidermal differentiation, including genes in 1q21 loci and corresponding to the epidermal differentiation complex. Correlation analysis of genes concordantly expressed in Barrett's esophagus and adenocarcinoma revealed 21 genes that represent potential genetic markers of disease progression and pharmacologic targets for treatment intervention. PCR analysis of genes selected based on DNA array experiments revealed that estimation of the ratios of GATA6 to SPRR3 allows discrimination among normal esophageal epithelium, Barrett's dysplasia, and adenocarcinoma.

Surveillance for Barrett's oesophagus: is there light the end of the metaplastic tunnel?

Metaplastic change of the oesophageal epithelium from normal stratified squamous to columnar-lined with intestinal metaplasia results in an increased risk of development of adenocarcinoma. As a result, endoscopic surveillance has been recommended for the surgically-fit patient. The evidence that these programmes are altering clinical outcome to any major degree, however, is weak. This review highlights some of the areas of controversy and outstanding points that need to be clarified to allow establishment of evidence-based medicine for this condition.

Screening for Barrett's esophagus in colonoscopy patients with and without heartburn

BACKGROUND & AIMS

The population prevalence of Barrett's esophagus (BE) is uncertain. Our aim was to describe the prevalence of BE in a volunteer population.

METHODS

Upper endoscopy (EGD) was performed in 961 persons with no prior history of EGD who were scheduled for colonoscopy. Symptom questionnaires were completed prior to endoscopy. Biopsy specimens were taken from the gastric cardia and any columnar mucosa extending > or =5 mm into the tubular esophagus and from the stomach for H. pylori infection in the last 812 patients.

RESULTS

The study sample was biased toward persons undergoing colonoscopy, males, and persons with upper GI symptoms. The prevalence of BE was 65 of 961 (6.8%) patients, including 12 (1.2%) with long-segment BE (LSBE). Among 556 subjects who had never had heartburn, the prevalences of BE and LSBE were 5.6% and 0.36%, respectively. Among 384 subjects with a history of any heartburn, the prevalences of BE and LSBE were 8.3% and 2.6%, respectively. In a univariate analysis, LSBE was more common in those with any heartburn vs. those with no heartburn (P = 0.01), but the sample size was insufficient to allow multivariate analysis of predictors of LSBE. In a multivariate analysis, BE was associated with increasing age (P = 0.02), white race (P = 0.03), and negative H. pylori status (P = 0.04). Overall, BE was not associated with heartburn, although heartburn was more common in persons with LSBE or circumferential short segments.

CONCLUSIONS

LSBE is very uncommon in patients who have no history of heartburn. SSBE is relatively common in persons age > or =40 years with no prior endoscopy, irrespective of heartburn history.

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

Most available information on the epidemiology of Barrettacute;s esophagus (BE) relates to patients with long segments (> 3 cm) of specialized intestinal metaplasia (SIM). Its prevalence is 3% in patients undergoing endoscopy for reflux symptoms and 1% in those undergoing endoscopy for any clinical indication. The latter prevalence is similar to the 1% found in autopsy series. A "silent majority" with BE remain unrecognized in the general population. BE is more common in men, and the prevalence rises with age. Recent endoscopic series document a rise in the diagnosis of endoscopically apparent short segments (< 3 cm) of BE (SSBE). The prevalence of SSBE in both unselected and reflux patients is 8% to 12%. Specialized intestinal metaplasia at the cardia, below a normal-appearing squamocolumnar junction, has been reported to vary from 6% to 25% in patients presenting for upper endoscopy. Unlike patients with long segment Barrett's esophagus (LSBE), the role of gastroesophageal reflux disease in the pathogenesis of SSBE and SIM of the cardia is controversial. Recent data suggest that the etiology of SIM of the cardia might be secondary to Helicobacter pylori infection, although the role of other environmental factors cannot be ruled out. The incidence of adenocarcinoma of the esophagus and esophagogastric juction (EGJ) has been increasing over the past 15 years in Western countries. Surgical series and population-based studies show that by 1994 adenocarcinomas of the esophagus accounted for half of all esophageal cancer among white men. LSBE and SSBE predispose to the development of adenocarcinoma of the esophagus and EGJ. The role of SIM of the cardia as a precursor lesion for EGJ adenocarcinoma is still unclear. The prevalences of dysplasia in LSBE and SSBE are around 6% and 8%, respectively. The incidence of adenocarcinoma in patients with LSBE is about 1 in 100 patient-years. Cancer risk for SSBE and SIM at the cardia is unknown. Smoking and obesity increase the risk for esophageal and EGJ adenocarcinomas.

Barrett's esophagus prevalence and epidemiology

These epidemiologic studies suggest that gastroesophageal reflux and incompetence of the LES are the most important factors in development of this condition. An unexplained genetic factor must be present, however, to explain the predominance of BE in white middle-aged men.

Upper endoscopy as a screening and surveillance tool in esophageal adenocarcinoma: a review of the evidence

Esophageal adenocarcinoma is a rare cancer that is increasing rapidly in incidence. Because gastroesophageal reflux disease (GERD) is a risk factor for the development of this cancer, endoscopic screening of individuals with GERD symptoms and endoscopic surveillance of those who are found to have Barrett's esophagus (BE), the presumed precursor to adenocarcinoma, have been proposed. Although no direct data support endoscopic screening or surveillance, several lines of indirect evidence are available. We apply a set of criteria for the evaluation of screening programs to endoscopic screening of subjects with reflux and endoscopic surveillance of subjects with BE. A critical examination of the data supporting these practices shows that considerable gaps exist in our knowledge regarding endoscopy as a screening test in GERD, making us unable to support this practice based on current evidence. Although no controlled trials exist to substantiate the effectiveness of surveillance programs for subjects with BE, some stronger indirect evidence does support this practice. However, further studies are necessary to substantiate the effectiveness and cost-effectiveness of endoscopic surveillance in BE. Based on the currently available data, consideration should be given to expanding the intervals between endoscopic surveillance sessions.

Prevalence of intestinal metaplasia in the distal oesophagus, oesophagogastric junction and gastric cardia in symptomatic patients in north-east Italy: a prospective, descriptive survey. The Italian Ulcer Study Group "GISU"

BACKGROUND

Incidence of adenocarcinoma of distal oesophagus and gastric cardia, probably arising from areas of intestinal metaplasia, has been increasing rapidly.

AIMS

To define prevalence of intestinal metaplasia of distal oesophagus, oesophagogastric junction and gastric cardia and to evaluate potential associated factors, by means of a prospective multicentre study including University and teaching hospitals, and primary and tertiary care centres.

PATIENTS

Each of 24 institutions involved in study enrolled 10 consecutive patients undergoing first-time routine endoscopy for dyspeptic symptoms.

METHODS

Patients answered symptom questionnaires and underwent gastroscopy Three biopsies were taken from distal oesophagus, oesophago-gastric junction and gastric cardia, and were stained with haematoxylin and eosin. Specimens were also evaluated for Helicobacter pylori infection.

RESULTS

A total of 240 patients (124 male, 116 female; median age 56 years, range 20-90) were enrolled in study. Intestinal metaplasia affected distal oesophagus in 5, oesophago-gastric junction in 19 and gastric cardia in 10 patients. Low-grade dysplasia was found at distal oesophagus and/or oesophago-gastric junction of 3/24 patients with intestinal metaplasia vs 2/216 without intestinal metaplasia (p<0.05). A significant association was found between symptoms and presence of intestinal metaplasia, regardless of location, and between Helicobacter pylori infection and intestinal metaplasia at oesophago-gastric junction.

CONCLUSIONS

Intestinal metaplasia of distal oesophagus, oesophagogastric-junction and gastric cardia is found in a significant proportion of symptomatic patients undergoing gastroscopy and is associated with dysplasia in many cases. Although prevalence of dysplasia seems to decrease when specialized columnar epithelium is found in short segment, or even focally in oesophago-gastric junction, these small foci of intestinal metaplastic cells may represent source of most adenocarcinomas of cardia.