Variable pathologic interpretation of columnar lined esophagus by general pathologists in community practice

Development of a deep learning model for the histologic diagnosis of dysplasia in Barrett's esophagus

BACKGROUND AND AIMS

The risk of progression in Barrett's esophagus (BE) increases with development of dysplasia. There is a critical need to improve the diagnosis of BE dysplasia, given substantial interobserver disagreement among expert pathologists and overdiagnosis of dysplasia by community pathologists. We developed a deep learning model to predict dysplasia grade on whole-slide imaging.

METHODS

We digitized nondysplastic BE (NDBE), low-grade dysplasia (LGD), and high-grade dysplasia (HGD) histology slides. Two expert pathologists confirmed all histology and digitally annotated areas of dysplasia. Training, validation, and test sets were created (by a random 70/20/10 split). We used an ensemble approach combining a "you only look once" model to identify regions of interest and histology class (NDBE, LGD, or HGD) followed by a ResNet101 model pretrained on ImageNet applied to the regions of interest. Diagnostic performance was determined for the whole slide.

RESULTS

We included slides from 542 patients (164 NDBE, 226 LGD, and 152 HGD) yielding 8596 bounding boxes in the training set, 1946 bounding boxes in the validation set, and 840 boxes in the test set. When the ensemble model was used, sensitivity and specificity for LGD was 81.3% and 100%, respectively, and >90% for NDBE and HGD. The overall positive predictive value and sensitivity metric (calculated as F1 score) was .91 for NDBE, .90 for LGD, and 1.0 for HGD.

CONCLUSIONS

We successfully trained and validated a deep learning model to accurately identify dysplasia on whole-slide images. This model can potentially help improve the histologic diagnosis of BE dysplasia and the appropriate application of endoscopic therapy.

Prevention Strategies for Esophageal Cancer-An Expert Review

In the last 30 years, we have witnessed a rapid increase in the incidence and prevalence of esophageal cancer in many countries around the word. However, despite advancements in diagnostic technologies, the early detection of this cancer is rare, and its prognosis remains poor, with only about 20% of these patients surviving for 5 years. The two major forms are the esophageal squamous cell carcinoma (ESCC), which is particularly frequent in the so-called Asian belt, and the esophageal adenocarcinoma (EAC), which prevails in Western populations. This review provides a summary of the epidemiological features and risk factors associated with these tumors. Moreover, a major focus is posed on reporting and highlighting the various preventing strategies proposed by the most important international scientific societies, particularly in high-risk populations, with the final aim of detecting these lesions as early as possible and therefore favoring their definite cure. Indeed, we have conducted analysis with attention to the current primary, secondary and tertiary prevention guidelines in both ESCC and EAC, attempting to emphasize unresolved research and clinical problems related to these topics in order to improve our diagnostic strategies and management.

Best Practices in Surveillance for Barrett's Esophagus

Barrett's esophagus is the precursor lesion for esophageal adenocarcinoma. The goals of endoscopic surveillance are to detect dysplasia and early esophageal adenocarcinoma in order to improve patient outcomes. Despite the ongoing debate regarding the efficacy of surveillance, all current gastrointestinal societies recommend surveillance at this time. Optimal surveillance technique includes adequate inspection time, evaluation using high-definition white light and chromoendoscopy, appropriate documentation of the metaplastic segment using the Prague C & M criteria as well as the Paris classification should lesions be found, utilization of the Seattle biopsy protocol, and endoscopic resection of visible lesions.

Indian consensus on gastroesophageal reflux disease in adults: A position statement of the Indian Society of Gastroenterology

The Indian Society of Gastroenterology developed this evidence-based practice guideline for management of gastroesophageal reflux disease (GERD) in adults. A modified Delphi process was used to develop this consensus containing 58 statements, which were generated by electronic voting iteration as well as face-to-face meeting and review of the supporting literature primarily from India. These statements include 10 on epidemiology, 8 on clinical presentation, 10 on investigations, 23 on treatment (including medical, endoscopic, and surgical modalities), and 7 on complications of GERD. When the proportion of those who voted either to accept completely or with minor reservation was 80% or higher, the statement was regarded as accepted. The prevalence of GERD in India ranges from 7.6% to 30%, being  < 10% in most population studies, and higher in cohort studies. The dietary factors associated with GERD include use of spices and non-vegetarian food. Helicobacter pylori is thought to have a negative relation with GERD; H. pylori negative patients have higher grade of symptoms of GERD and esophagitis. Less than 10% of GERD patients in India have erosive esophagitis. In patients with occasional or mild symptoms, antacids and histamine H2 receptor blockers (H2RAs) may be used, and proton pump inhibitors (PPI) should be used in patients with frequent or severe symptoms. Prokinetics have limited proven role in management of GERD.

Substantial Interobserver Agreement in the Diagnosis of Dysplasia in Barrett Esophagus Upon Review of a Patient's Entire Set of Biopsies

The pathologic diagnosis of dysplasia in Barrett esophagus (BE) suffers from interobserver disagreement. Many of the studies demonstrating disagreement in the diagnosis of dysplasia have pathologists review individual biopsy slides in isolation. To more closely mimic daily practice, 3 pathologists reviewed hematoxylin and eosin slides made from 549 individual biopsy jars obtained from 129 unique patients with a diagnosis of BE. Each pathologist reviewed the entirety of a given patient's biopsy material. The grade of dysplasia present in each biopsy jar was given as well as an overall highest grade of dysplasia from the patient's entire set of biopsies. The interobserver agreement in the diagnosis of dysplasia per biopsy jar and per patient's set of biopsies was measured by Fleiss κ statistic for multiple raters. The κ values for each diagnosis was higher in the per patient analysis compared with the per biopsy jar analysis indicating that pathologists are more likely to agree on the overall grade of dysplasia compared with the grade in an individual biopsy jar. In the per patient analysis, the interobserver agreement in the diagnosis of nondysplastic BE and high-grade dysplasia were substantial (κ=0.66; 95% confidence interval [CI], 0.56-0.76 and κ=0.76; 95% CI, 0.66-0.86, respectively). The interobserver agreement in the diagnosis of low-grade dysplasia (LGD) was fair (κ=0.31; 95% CI, 0.21-0.42). When LGD and high-grade dysplasia were collapsed into 1 category of positive for dysplasia, the interobserver agreement in the per patient analysis remained substantial (κ=0.70; 95% CI, 0.60-0.80), suggesting that much of the disagreement in LGD is not due to lack of recognition of dysplastic Barrett's mucosa, but rather the degree of dysplasia. These results indicate that pathologists can reliably distinguish between nondysplastic BE and dysplastic BE when a patient's entire set of biopsies is reviewed as a group. When second opinions are obtained, all available slides from that endoscopic procedure should be sent for review.

Low-grade dysplasia diagnosis ratio and progression metrics identify variable Barrett's esophagus risk stratification proficiency in independent pathology practices

BACKGROUND AND AIMS

The diagnosis of low-grade dysplasia (LGD) in Barrett's esophagus (BE) is subject to substantial interobserver variation. Our central aim in this study is to compare independent pathology practices using objective measures of BE risk stratification proficiency, including frequency of diagnosis and rate of progression, with high-grade dysplasia (HGD) or adenocarcinoma (EAC) after the first diagnosis of LGD.

METHODS

We retrospectively evaluated over 29,000 endoscopic biopsy cases to identify 4734 patients under endoscopic biopsy surveillance for BE in a healthcare system with multiple independent pathology practices: a subspecialized GI pathology group (SSGI; 162 BE cases per pathologist annually), 3 high BE volume general surgical pathology practices (GSPs; >50 BE cases per pathologist annually), and multiple low BE volume GSPs (10.6 BE cases per pathologist annually). We measured LGD diagnosis frequencies and rates of diagnostic progression to HGD or EAC in patients diagnosed with LGD.

RESULTS

The proportion of all BE cases diagnosed as LGD (LGD/BE diagnosis ratio) ranged from 1.1% to 6.8% in the different hospital settings (P < .001). The cumulative proportion of patients with HGD or EAC within 2 years of the first diagnosis of LGD was 35.3% in the SSGI and ranged from 1.4% to 14.3% in the GSPs (P < .001). LGD diagnosed by the GSP with the lowest LGD/BE diagnosis ratio had an adjusted risk of progression similar to LGD diagnosed by subspecialists (hazard ratio, .42; 95% CI, .06-3.03). However, when LGD was diagnosed by other generalists, the adjusted risk of progression was 79% to 91% lower than subspecialists (P < .001). When LGD was diagnosed in a low-volume GSP practice, the risk of progression was not significantly increased relative to patients with nondysplastic BE (hazard ratio, 1.3; 95% CI, .4-3.9).

CONCLUSIONS

General surgical pathologists and subspecialists show highly significant differences with respect to LGD/BE ratio, risk of progression relative to nondysplastic BE, crude annual progression rates, and the cumulative 2-year progression rate after LGD. These metrics can be used to assess proficiency in BE risk stratification in historical cases. Some general practitioners were able to achieve results similar to subspecialists. General surgical pathologists with little annual experience evaluating BE biopsy specimens did not successfully risk stratify patients with BE.

Screening and Surveillance for Barrett's Esophagus: Is It Cost-Effective?

The cost-effectiveness of screening and surveillance for Barrett's esophagus continues to evolve as the incidence of esophageal adenocarcinoma increases, biomarkers enhance the identification of individuals at highest risk for developing cancer, and endoscopic eradication of Barrett's esophagus improves. Screening to detect Barrett's esophagus may be cost-effective in selected high-risk groups based on age, race, sex and other factors such as symptoms of heartburn. Currently, endoscopic eradication therapy for Barrett's esophagus and high-grade dysplasia is a cost-effective intervention, while endoscopic therapy for non-dysplastic Barrett's esophagus is not a cost-effective strategy. As diagnosis of low-grade dysplasia improves, endoscopic eradication therapy may also prove to be a cost-effective intervention.

Suboptimal Agreement Among Cytopathologists in Diagnosis of Malignancy Based on Endoscopic Ultrasound Needle Aspirates of Solid Pancreatic Lesions: A Validation Study

BACKGROUND & AIMS

Despite the widespread use of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) to sample pancreatic lesions and the standardization of pancreaticobiliary cytopathologic nomenclature, there are few data on inter-observer agreement among cytopathologists evaluating pancreatic cytologic specimens obtained by EUS-FNA. We developed a scoring system to assess agreement among cytopathologists in overall diagnosis and quantitative and qualitative parameters, and evaluated factors associated with agreement.

METHODS

We performed a prospective study to validate results from our pilot study that demonstrated moderate to substantial inter-observer agreement among cytopathologists for the final cytologic diagnosis. In the first phase, 3 cytopathologists refined criteria for assessment of quantity and quality measures. During phase 2, EUS-FNA specimens of solid pancreatic lesions from 46 patients were evaluated by 11 cytopathologists at 5 tertiary care centers using a standardized scoring tool. Individual quantitative and qualitative measures were scored and an overall cytologic diagnosis was determined. Clinical and EUS parameters were assessed as predictors of unanimous agreement. Inter-observer agreement (IOA) was calculated using multi-rater kappa (κ) statistics and a logistic regression model was created to identify factors associated with unanimous agreement.

RESULTS

The IOA for final diagnoses, based on cytologic analysis, was moderate (κ = 0.56; 95% CI, 0.43-0.70). Kappa values did not increase when categories of suspicious for malignancy, malignant, and neoplasm were combined. IOA was slight to moderate for individual quantitative (κ = 0.007; 95% CI, -0.03 to -0.04) and qualitative parameters (κ = 0.5; 95% CI, 0.47-0.53). Jaundice was the only factor associated with agreement among all cytopathologists on multivariate analysis (odds ratio for unanimous agreement, 5.3; 95% CI, 1.1-26.89).

CONCLUSIONS

There is a suboptimal level of agreement among cytopathologists in the diagnosis of malignancy based on analysis of EUS-FNA specimens obtained from solid pancreatic masses. Strategies are needed to refine the cytologic criteria for diagnosis of malignancy and enhance tissue acquisition techniques to improve diagnostic reproducibility among cytopathologists.

Longitudinal outcomes of radiofrequency ablation versus surveillance endoscopy for Barrett's esophagus with low-grade dysplasia

Radiofrequency ablation of Barrett's esophagus with low-grade dysplasia is recommended in recent American College of Gastroenterology guidelines, with endoscopic surveillance considered a reasonable alternative. Few studies have directly compared outcomes of radiofrequency ablation to surveillance and those that have are limited by short duration of follow-up. This study aims to compare the long-term effectiveness of radiofrequency ablation versus endoscopic surveillance in a large, longitudinal cohort of patients with Barrett's esophagus, and low-grade dysplasia.We conducted a retrospective analysis of patients with confirmed low-grade dysplasia at a single academic medical center from 1991 to 2014. Patients progressing to high-grade dysplasia or esophageal adenocarcinoma within one year of index LGD endoscopy were defined as missed dysplasia and excluded. Risk factors for progression were assessed via Cox proportional hazards model. Comparison of progression risk was conducted using a Kaplan-Meier analysis. Subset analyses were conducted to examine the effect of reintroducing early progressors and excluding patients diagnosed prior to the advent of ablative therapy. Of 173 total patients, 79 (45.7%) underwent radiofrequency ablation while 94 (54.3%) were untreated, with median follow up of 90 months. Seven (8.9%) patients progressed to high-grade dysplasia or adenocarcinoma despite ablation, compared with 14 (14.9%) undergoing surveillance (P = 0.44). This effect was preserved when patients diagnosed prior to the introduction of radiofrequency ablation were excluded (8.9% vs 13%, P = 0.68). Reintroduction of patients progressing within the first year of follow-up resulted in a trend toward significance for ablation versus surveillance (11.1% vs 23.8%, P = 0.053).In conclusion, progression to high-grade dysplasia or adenocarcinoma was not significantly reduced in the radiofrequency ablation cohort when compared to surveillance. Despite recent studies suggesting the superiority of radiofrequency ablation in reducing progression, diligent endoscopic surveillance may provide similar long-term outcomes.

From Heartburn to Barrett's Esophagus, and Beyond

BACKGROUND

Gastroesophageal reflux disease (GERD) affects an estimated 20% of the population in the USA, and its prevalence is increasing worldwide. About 10-15% of patients with GERD will develop Barrett's esophagus (BE).

AIMS

The aims of this study were to review the available evidence of the pathophysiology of BE and the role of anti-reflux surgery in the treatment of this disease.

RESULTS

The transformation of the squamous epithelium into columnar epithelium with goblet cells is due to the chronic injury produced by repeated reflux episodes. It involves genetic mutations that in some patients may lead to high-grade dysplasia and cancer. There is no strong evidence that anti-reflux surgery is associated with resolution or improvement in BE, and its indications should be the same as for other GERD patients without BE.

CONCLUSIONS

Patients with BE without dysplasia require endoscopic surveillance, while those with low- or high-grade dysplasia should have consideration of endoscopic eradication therapy followed by surveillance. New endoscopic treatment modalities are being developed, which hold the promise to improve the management of patients with BE.

FABP1 and Hepar expression levels in Barrett's esophagus and associated neoplasia in an Asian population

INTRODUCTION

Barrett's esophagus (BE) is a premalignant condition associated with esophageal adenocarcinoma (EAC). Evidence highlights that EAC is associated with an estimated 5-year survival of approximately 10-15%. Therefore, there is a need to determine which biomarkers are of value in the diagnosis of BE and beyond. The aim of our study was to evaluate the clinical significance of markers known to be expressed across BE and associated neoplasia.

METHODS

Retrospective tissues were obtained from columnar lined esophagus (CLE) without goblet cells (n=22), BE (n=29), dysplasia (n=14), and EAC (n=10). Standardised immunohistochemistry for FABP1, Hepar, CDH17, and CDX2 were performed followed by quantitative staining and statistical analysis.

RESULTS

FABP1 expression was negligible in CLE and was highest in BE, with a further decrease in expression in dysplasia and EAC. Hepar expression was also negligible in CLE and was highest in dysplasia and BE, with a reduced expression in EAC. CDH17 and CDX2 showed a significantly higher expression in BE, dysplasia, and EAC compared to CLE.

CONCLUSION

All 4 markers were excellent diagnostic panels to clearly discriminate BE from CLE. Moreover, as FABP1 and Hepar have different expression levels in dysplasia and EAC, these markers could function as key diagnostic aids in helping to determine the state of disease progression.

Current Concepts in Treatment of Barrett's Esophagus With and Without Dysplasia

BACKGROUND

Around 10-15% of patients with gastroesophageal reflux disease will develop Barrett's esophagus (BE). The development of novel endoscopic modalities has changed the management of BE in the last decade.

AIM

The aim of this study was to review the current evidence for the treatment of BE with and without dysplasia.

RESULTS

In patients with BE without dysplasia, antireflux surgery should not be suggested as a modality to prevent the malignant transformation of BE, but its indications should be the same as for other patients with gastroesophageal reflux. Endoscopic surveillance at intervals of 3-5 years is recommended for these patients. For patients with BE with low-grade dysplasia, radiofrequency ablation (RFA) is the preferred treatment modality, while endoscopic surveillance every 12 months is an acceptable alternative in patients with life-limiting comorbidities. For most patients with BE and high-grade dysplasia, RFA is the preferred treatment strategy. Patients with intramucosal adenocarcinoma (T1a), should be treated with EMR followed by ablative therapy, in order to eradicate the remaining intestinal metaplasia. Endoscopic resection may be suitable for low-risk T1b tumors (well-differentiated, without lymphovascular invasion, and with superficial submucosal invasion); however, further data are necessary to better risk stratify this group.

CONCLUSIONS

Patients with BE without dysplasia should undergo endoscopic surveillance every 3-5 years. Endoscopic ablative therapy (RFA) is the preferred treatment modality for dysplastic BE. Patients with T1a adenocarcinoma should be treated with EMR followed by ablative therapy. Low-risk T1b tumors may be suitable for endoscopic resection.

CEACAM 6, a novel marker for the diagnosis of Barrett's esophagus

Barrett's esophagus (BE) is a premalignant condition associated with the development of esophageal adenocarcinoma (EAC). Despite the low risk of progression to EAC, evidence highlights the notably poor survival rates of this malignancy. The mainstay form of diagnosis of BE is endoscopy and biopsy sampling. However, research emphasizes limitations with regards to the histological detection of BE and associated dysplasia. The aim of this study is to evaluate the clinical significance of CEACAM6 as a potential biomarker for the diagnosis of BE and beyond. Retrospective tissue samples were obtained from columnar lined esophagus without goblet cells (n = 27), BE (n = 18), BE associated dysplasia (n = 16), and EAC (n = 24). Standardized immunohistochemistry for CEACAM6 was performed followed by quantitative staining analysis. Statistical analysis across the BE spectrum for CEACAM6 was undertaken and a P value <0.05 was considered significant. CEACAM6 expression increased from columnar lined epithelium (CLE) to BE with a subsequent decrease to dysplasia and adenocarcinoma. The expression of CEACAM6 was significant from CLE to BE at p 0.001, CLE to dysplasia at p 0.001, BE to dysplasia at p 0.006, CLE to adenocarcinoma at p 0.001 and BE to adenocarcinoma at p 0.001. There was no significant difference in expression between dysplasia and adenocarcinoma (P = 0.15). Our findings highlight the increasing expression of CEACAM6 from CLE to BE with a subsequent decrease to dysplasia and adenocarcinoma. In view of this, we advocate the utilization of this marker for the enhanced diagnosis of BE and for the distinction of BE and dysplasia.

Effectiveness and Cost-Effectiveness of Endoscopic Screening and Surveillance

Guidelines for the screening and surveillance of Barrett's esophagus continue to evolve as the incidence of esophageal adenocarcinoma increases, identification of individuals at highest risk for cancer improves, and management of dysplasia evolves. This article reviews related studies and economic analyses. Advances in diagnosis offer promising strategies to help focus screening efforts on those individuals who are most likely to develop esophageal adenocarcinoma.

Meta-analysis of biomarkers predicting risk of malignant progression in Barrett's oesophagus

BACKGROUND

Barrett's oesophagus is a precursor to the development of oesophageal adenocarcinoma. This study sought to clarify the role of genetic, chromosomal and proliferation biomarkers that have been the subjects of multiple studies through meta-analysis.

METHODS

MEDLINE, Embase, PubMed and the Cochrane Library were searched for clinical studies assessing the value of p53, p16, Ki-67 and DNA content abnormalities in Barrett's oesophagus. The main outcome measure was the risk of development of high-grade dysplasia (HGD) or oesophageal adenocarcinoma.

RESULTS

Some 102 studies, with 12 353 samples, were identified. Mutation (diagnostic odds ratio (DOR) 10·91, sensitivity 47 per cent, specificity 92 per cent, positive likelihood ratio (PLR) 4·71, negative likelihood ratio (NLR) 0·65, area under the curve (AUC) 0·792) and loss (DOR 16·16, sensitivity 31 per cent, specificity 98 per cent, PLR 6·66, NLR 0·41, AUC 0·923) of p53 were found to be superior to the other p53 abnormalities (loss of heterozygosity (LOH) and overexpression). Ki-67 had high sensitivity in identifying high-risk patients (DOR 5·54, sensitivity 82 per cent, specificity 48 per cent, PLR 1·59, NLR 0·42, AUC 0·761). Aneuploidy (DOR 12·08, sensitivity 53 per cent, specificity 87 per cent, PLR 4·26, NLR 0·42, AUC 0·846), tetraploidy (DOR 5·87, sensitivity 46 per cent, specificity 85 per cent, PLR 3·47, NLR 0·65, AUC 0·793) and loss of Y chromosome (DOR 9·23, sensitivity 68 per cent, specificity 80 per cent, PLR 2·67, NLR 0·49, AUC 0·807) also predicted malignant development, but p16 aberrations (hypermethylation, LOH, mutation and loss) failed to demonstrate any advantage over the other biomarkers studied.

CONCLUSION

Loss and mutation of p53, and raised level of Ki-67 predicted malignant progression in Barrett's oesophagus.

Endoscopic ablation is a cost-effective cancer preventative therapy in patients with Barrett's esophagus who have elevated genomic instability

BACKGROUND

The surveillance of patients with nondysplastic Barrett's esophagus (NDBE) has a high cost and is of limited effectiveness in preventing esophageal adenocarcinoma (EAC). Ablation for NDBE remains expensive and controversial. Biomarkers of genomic instability have shown promise in identifying patients with NDBE at high risk for progression to EAC. Here, we evaluate the cost-effectiveness of using such biomarkers to stratify patients with NDBE by risk for EAC and, subsequently, the cost-effectiveness of ablative therapy.

METHODS

A Markov decision tree was used to evaluate four strategies in a hypothetical cohort of 50-year old patients with NDBE over their lifetime: strategy I, natural history without surveillance; strategy II, surveillance per current guidelines; strategy III, ablation for all patients; strategy IV, risk stratification with use of a biomarker panel to assess genomic instability (i. e., mutational load [ML]). Patients with no ML underwent minimal surveillance, patients with low ML underwent standard surveillance, and patients with high ML underwent ablation. The incremental cost-effectiveness ratio (ICER) and incremental net health benefit (INHB) were assessed.

RESULTS

Strategy IV provided the best values for quality-adjusted life years (QALYs), ICER, and INHB in comparison with strategies II and III. RESULTS were robust in sensitivity analysis. In a Monte Carlo analysis, the relative risk for the development of cancer in the patients managed with strategy IV was decreased. Critical determinants of strategy IV cost-effectiveness were the complete response rate, cost of ablation, and surveillance interval in patients with no ML.

CONCLUSION

The use of ML to stratify patients with NDBE by risk was the most cost-effective strategy for preventive EAC treatment. Targeting ablation toward patients with high ML presents an opportunity for a paradigm shift in the management of NDBE.

ACG Clinical Guideline: Diagnosis and Management of Barrett's Esophagus

Barrett's esophagus (BE) is among the most common conditions encountered by the gastroenterologist. In this document, the American College of Gastroenterology updates its guidance for the best practices in caring for these patients. These guidelines continue to endorse screening of high-risk patients for BE; however, routine screening is limited to men with reflux symptoms and multiple other risk factors. Acknowledging recent data on the low risk of malignant progression in patients with nondysplastic BE, endoscopic surveillance intervals are attenuated in this population; patients with nondysplastic BE should undergo endoscopic surveillance no more frequently than every 3-5 years. Neither routine use of biomarker panels nor advanced endoscopic imaging techniques (beyond high-definition endoscopy) is recommended at this time. Endoscopic ablative therapy is recommended for patients with BE and high-grade dysplasia, as well as T1a esophageal adenocarcinoma. Based on recent level 1 evidence, endoscopic ablative therapy is also recommended for patients with BE and low-grade dysplasia, although endoscopic surveillance continues to be an acceptable alternative. Given the relatively common recurrence of BE after ablation, we suggest postablation endoscopic surveillance intervals. Although many of the recommendations provided are based on weak evidence or expert opinion, this document provides a pragmatic framework for the care of the patient with BE.

Cost considerations in implementing a screening and surveillance strategy for Barrett's oesophagus

There is increasing concern over the rising costs of healthcare leading to debate regarding the use of resources to implement preventive strategies. Oesophageal adenocarcinoma and its precursor, Barrett's oesophagus provides an excellent opportunity to highlight this issue since cancer is uncommon even among individuals with documented Barrett's oesophagus. This review provides a brief introduction to economic analysis in healthcare and summarizes published studies of the cost-effectiveness of strategies to reduce mortality from cancer. Current best estimates highlight the cost-effectiveness of endoscopic ablation among patients with Barrett's oesophagus and high-grade dysplasia and the low cost-effectiveness of ablation among patients without dysplasia. The cost-effectiveness of ablation among patients with Barrett's and low-grade dysplasia is poorly defined due to the ambiguity of diagnosing dysplasia, the unknown risk of cancer among patients with low-grade dysplasia, and the uncertain durability of ablation to maintain remission from metaplasia and dysplasia and prevent cancer.

Barrett's oesophagus: frequency and prediction of dysplasia and cancer

The incidence of oesophageal adenocarcinoma is continuing to increase at an alarming rate in the Western world today. Barrett's oesophagus is a clearly recognized risk factor for the development of oesophageal adenocarcinoma, but the overwhelming majority of patients with Barrett's oesophagus will never develop oesophageal cancer. A number of endoscopic, histologic and epidemiologic risk factors identify Barrett's oesophagus patients at increased risk for progression to high-grade dysplasia and oesophageal adenocarcinoma. Endoscopic factors include segment length, mucosal abnormalities as seemingly trivial as oesophagitis and the 12 to 6 o'clock hemisphere of the oesophagus. Both intestinal metaplasia and low grade dysplasia, the latter only if confirmed by a pathologist with expertise in Barrett's oesophagus pathologic interpretation are the histologic risk factors for progression. Epidemiologic risk factors include ageing, male gender, obesity, and smoking. Factors that may protect against the development of adenocarcinoma include a diet rich in fruits and vegetables, and the use of proton pump inhibitors, aspirin/NSAIDs and statins.

Evidence-based endoscopic management of Barrett's esophagus

Barrett’s esophagus (BE) develops as a consequence of chronic esophageal acid exposure, and is the major risk factor for esophageal adenocarcinoma (EAC). The practices of endoscopic screening for—and surveillance of—BE, while widespread, have failed to reduce the incidence of EAC. The majority of EACs are diagnosed in patients without a known history of BE, and current diagnostic tools are lacking in their ability to stratify patients with BE into those at low risk and those at high risk for progression to malignancy. Nonetheless, advances in endoscopic imaging and mucosal therapeutics have provided unprecedented opportunities for intervention for BE, and have vastly altered the approach to management of BE-associated mucosal neoplasia.

Progression of Barrett oesophagus: role of endoscopic and histological predictors

Barrett oesophagus is an important precursor lesion for the development of oesophageal adenocarcinoma (OAC). Upper gastrointestinal endoscopy is the modality most widely used to visualize and biopsy the oesophagus to establish a diagnosis. Additional clues are available at the time of endoscopy that can identify high-risk features known to increase the risk of progression to OAC, such as the length of the Barrett oesophagus segment, length of hiatal hernia and the presence of nodularity or visible endoscopic lesions in this segment. Until molecular biomarkers are identified and validated as adjunctive tools for risk stratification, knowledge of endoscopic features could complement dysplasia grading for risk stratification of patients with Barrett oesophagus and identify subgroups at risk of progression to OAC. This approach would, in turn, facilitate more rational tailoring of endoscopic surveillance. This Review summarizes the current role of endoscopic and histological factors involved in neoplastic progression of Barrett oesophagus to OAC, and provides an overview of the risk-prediction models that have utilized endoscopic and histological factors for risk stratification in patients with Barrett oesophagus.

Low grade dysplasia in Barrett’s esophagus: Should we worry?

The optimal management for low-grade dysplasia (LGD) in Barrett’s esophagus is unclear. In this article the importance of LGD is discussed, including the significant risk of progression to esophageal adenocarcinoma. Endoscopic surveillance is a management option but is plagued by sampling error and issues of suboptimal endoscopy. Furthermore endoscopic surveillance has not been demonstrated to be cost-effective or to reduce cancer mortality. The emergence of endoluminal therapy over the past decade has resulted in a paradigm shift in the management of LGD. Ablative therapy, including radiofrequency ablation, has demonstrated promising results in the management of LGD with regards to safety, cost-effectiveness, durability and reduction in cancer risk. It is, however, vital that a shared-decision making process occurs between the physician and the patient as to the preferred management of LGD. As such the management of LGD should be “individualised.”

Cost-effectiveness of endoscopic surveillance of non-dysplastic Barrett's esophagus

BACKGROUND

Endoscopic surveillance for non-dysplastic Barrett's esophagus (BE) is contentious and its cost effectiveness unclear.

OBJECTIVE

To perform an economic analysis of endoscopic surveillance strategies.

DESIGN

Cost-utility analysis by using a simulation Markov model to synthesize evidence from large epidemiologic studies and clinical data for surveillance, based on international guidelines, applied in a coordinator-managed surveillance program.

SETTING

Tertiary care hospital, South Australia.

PATIENTS

A total of 2040 patient-years of follow-up.

INTERVENTION

(1) No surveillance, (2) 2-yearly endoscopic surveillance of patients with non-dysplastic BE and 6-monthly surveillance of patients with low-grade dysplasia, (3) a hypothetical strategy of biomarker-modified surveillance.

MAIN OUTCOME MEASUREMENTS

U.S. cost per quality-adjusted life year (QALY) ratios.

RESULTS

Compared with no surveillance, surveillance produced an estimated incremental cost per QALY ratio of $60,858. This was reduced to $38,307 when surveillance practice was modified by a hypothetical biomarker-based strategy. Sensitivity analyses indicated that the likelihood that surveillance alone was cost-effective compared with no surveillance was 16.0% and 60.6% if a hypothetical biomarker-based strategy was added to surveillance, at an acceptability threshold of $100,000 per QALY gained.

LIMITATIONS

Treatment options for BE that overlap those for symptomatic GERD were omitted.

CONCLUSION

By using best available estimates of the malignant potential of BE, endoscopic surveillance of patients with non-dysplastic BE is unlikely to be cost-effective for the majority of patients and depends heavily on progression rates between dysplasia grades. However, strategies that modify surveillance according to cancer risk might be cost-effective, provided that high-risk individuals can be identified and prioritized for surveillance.

I-SCAN targeted versus random biopsies in Barrett's oesophagus

BACKGROUND

The accuracy and effectiveness of targeted oesophageal biopsies in Barrett's oesophagus to detect dysplasia using new magnification techniques are unknown. Aim of this study was to investigate whether the combined use of acetic acid, magnification and electronic filters allows the same accuracy as the four-quadrant random biopsies pattern; pathologist interobserver agreement both in low grade and high grade dysplasia was also assessed.

METHODS

Fifty-four consecutive patients newly diagnosed with Barrett's oesophagus were enrolled in a prospective study from a single endoscopy unit. Biopsies were evaluated by the local pathologist and by an expert pathologist from another pathology unit.

MAIN OUTCOME MEASUREMENT

Dysplasia detection rate and interobserver agreement for the histologic diagnosis of dysplasia.

RESULTS

The use of acetic acid, magnification and electronic filters showed an unacceptably low dysplasia detection rate by the two pathologists (9.2% and 5.5% for targeted biopsies, respectively). The interobserver agreement for low grade dysplasia between pathologists was low (Cohen's K weighted=0.45).

CONCLUSIONS

In an average setting, the standard four-quadrant method should still be preferred, along with the implementation of a routine second evaluation by an expert pathologist.

Optimized endoscopic autofluorescence spectroscopy for the identification of premalignant lesions in Barrett's oesophagus

OBJECTIVE

Fluorescence spectroscopy has the potential to detect early cellular changes in Barrett's oesophagus before these become visible. As the technique is based on varying concentrations of intrinsic fluorophores, each with its own optimal excitation wavelength, it is important to assess the optimal excitation wavelength(s) for identification of premalignant lesions in patients with Barrett's oesophagus.

METHODS

The endoscopic spectroscopy system used contained five (ultra)violet light sources (λexc=369-416 nm) to generate autofluorescence during routine endoscopic surveillance. Autofluorescence spectroscopy was followed by a biopsy for histological assessment and spectra correlation. Three intensity ratios (r1, r2, r3) were calculated by dividing the area, A, under the spectral curve of selected emission wavelength ranges for each spectrum generated by each excitation wavelength λexc as follows (Equation is included in full-text article.). Double intensity ratios were calculated using two excitation wavelengths.

RESULTS

Fifty-eight tissue areas from 22 patients were used for autofluorescence spectra analysis. Excitation with 395, 405 or 410 nm showed a significant (P≤0.0006) differentiation between intestinal metaplasia and grouped high-grade dysplasia/early carcinoma for intensity ratios r2 and r3. A sensitivity of 80.0% and specificity of 89.5% with an area under the ROC curve of 0.85 was achieved using 395 nm excitation and intensity ratio r3.

CONCLUSION

Double excitation showed no additional value over single excitation. The combination of 395 nm excitation and intensity ratio r3 showed optimal conditions to discriminate nondysplastic from early neoplasia in Barrett's oesophagus.

Cost-effectiveness of Barrett's oesophagus screening and surveillance

Endoscopic screening and surveillance of patients with Barrett's oesophagus to detect oesophageal cancer at earlier stages is contentious. As a consequence, their cost-effectiveness is also debatable. Current health economic evidence shows mixed results for demonstrating their value, mainly due to varied assumptions around progression rates to cancer, quality of life and treatment pathways. No randomized controlled trial exists to definitively support the efficacy of surveillance programs and one is unlikely to be undertaken. Contemporary treatment, cost and epidemiological data to contribute to cost-effectiveness analyses are needed. Risk assessment to stratify patients at low- or high-risk of developing cancer should improve cost-effectiveness outcomes as higher gains will be seen for those at higher risk, and medical resource use will be avoided in those at lower risk. Rapidly changing technologies for imaging, biomarker testing and less-invasive endoscopic treatments also promise to lower health system costs and avoid adverse events in patients.

Endocytoscopic visualization of squamous cell islands within Barrett's epithelium

AIM

To study the endocytoscopic visualization of squamous cell islands within Barrett's epithelium.

METHODS

Endocytoscopy (ECS) has been studied in the surveillance of Barrett's esophagus, with controversial results. In initial studies, however, a soft catheter type endocytoscope was used, while only methylene blue dye was used for the staining of Barrett's mucosa. Integrated type endocytoscopes (GIF-Q260 EC, Olympus Corp, Tokyo, Japan) have been recently developed, with the incorporation of a high-power magnifying endocytoscope into a standard endoscope together with narrow-band imaging (NBI). Moreover, double staining with a mixture of 0.05% crystal violet and 0.1% of methylene blue (CM) during ECS enables higher quality images comparable to conventional hematoxylin eosin histopathological images.

RESULTS

In vivo endocytoscopic visualization of papillary squamous cell islands within glandular Barrett's epithelium in a patient with long-segment Barrett's esophagus is reported. Conventional white light endoscopy showed typical long-segment Barrett's esophagus, with small squamous cell islands within normal Barrett's mucosa, which were better visualized by NBI endoscopy. ECS after double CM staining showed regular Barrett's esophagus, while higher magnification (× 480) revealed the orifices of glandular structures better. Furthermore, typical squamous cell papillary protrusion, classified as endocytoscopic atypia classification (ECA) 2 according to ECA, was identified within regular glandular Barrett's mucosa. Histological examination of biopsies taken from the same area showed squamous epithelium within glandular Barrett's mucosa, corresponding well to endocytoscopic findings.

CONCLUSION

To our knowledge, this is the first report of in vivo visualization of esophageal papillary squamous cell islands surrounded by glandular Barrett's epithelium.

Expert pathology review and endoscopic mucosal resection alters the diagnosis of patients referred to undergo therapy for Barrett's esophagus

BACKGROUND

Endoscopic therapy has emerged as an alternative to surgical esophagectomy for the management of Barrett's esophagus (BE)-associated neoplasia. Accurate pretreatment staging is essential to ensure an appropriate choice of therapy and optimal long-term outcomes. This study aimed to assess the frequency with which expert histopathologic review of biopsies combined with endoscopic mucosal resection (EMR) would alter the pretreatment diagnosis of BE-associated neoplasia.

METHODS

Patients referred to the Vanderbilt Barrett's Esophagus Endoscopic Treatment Program (V-BEET) were retrospectively identified. Demographic, histopathologic, and endoscopic data were extracted from the medical record.

RESULTS

For this study, 29 subjects referred for endoscopic staging of BE fulfilled the entry criteria. The referral diagnosis was low-grade dysplasia (LGD) in 3 % (1/29), high-grade dysplasia (HGD) in 62 % (18/29), intramucosal adenocarcinoma (T1a) adenocarcinoma in 17 % (5/29), and invasive adenocarcinoma in 17 % (5/29) of the subjects. Expert histopathologic review of available referral biopsy specimens altered the diagnosis in 33 % (5/15) of the cases. Further diagnostic staging with EMR showed BE without dysplasia in 10 % (3/29), LGD in 14 % (4/29), HGD in 34 % (10/29), T1a adenocarcinoma in 28 % (8/29), and invasive adenocarcinoma in 14 % (4/29) of the patients. The combination of expert histopathologic review and EMR altered the initial diagnosis for 55 % (16/29) of the subjects, with 56 % (9/16) upstaged to more advanced disease and 44 % (7/16) downstaged to less advanced disease.

CONCLUSIONS

The practice of combined expert histopathologic review and EMR alters the pretreatment diagnosis for the majority of patients with BE-associated neoplasia. Caution is advised for those embarking on endoscopic or surgical treatment for BE-associated neoplasia in the absence of these staging methods.

Diagnosis and management of Barrett's esophagus

Barrett esophagus is characterized by the replacement of squamous mucosa in the esophagus by specialized intestinal metaplasia. Its clinical significance lies in it being the strongest risk factor for and known precursor for esophageal adenocarcinoma. Diagnosis requires endoscopic confirmation of columnar metaplasia in the distal esophagus and histologic confirmation of specialized intestinal metaplasia. Recommendations for the management of subjects diagnosed with Barrett esophagus include periodic endoscopic surveillance to detect the development of high-grade dysplasia or adenocarcinoma. Careful endoscopic evaluation with high-resolution endoscopy and endoscopic resection is recommended in the evaluation of subjects with high-grade dysplasia and early adenocarcinoma.

Diagnosis and management of Barrett's esophagus

Barrett esophagus is characterized by the replacement of squamous mucosa in the esophagus by specialized intestinal metaplasia. Its clinical significance lies in it being the strongest risk factor for and known precursor for esophageal adenocarcinoma. Diagnosis requires endoscopic confirmation of columnar metaplasia in the distal esophagus and histologic confirmation of specialized intestinal metaplasia. Recommendations for the management of subjects diagnosed with Barrett esophagus include periodic endoscopic surveillance to detect the development of high-grade dysplasia or adenocarcinoma. Careful endoscopic evaluation with high-resolution endoscopy and endoscopic resection is recommended in the evaluation of subjects with high-grade dysplasia and early adenocarcinoma.

Radiofrequency ablation associated to mucosal resection in the oesophagus: experience in a single centre

Endoscopic resection (EMR) and radiofrequency ablation (RFA) form part of the treatment of Barrett's oesophagus (BO), dysplasia, superficial adenocarcinoma (OAC) associated with BO.

PATIENTS AND METHODS

Between June 2008 and April 2011, 34 patients underwent treatment with RFA (HALO system(®)), in a tertiary centre. For the study, patients were divided into two groups. Group 1 (16 patients of average 60 years old; 14 men, two women) received EMR and RFA. Group 2 (18 patients averaging 59 years age; 14 men, four women) received RFA without EMR in the year preceding the RFA.

RESULTS

In group 1, high grade dysplasia (HGD) was eradicated in 12 cases (92%), low grade dysplasia (LGD) in three cases (100%). Complete response occurred in nine cases (56%), partial response in 100% of cases. Mean follow-up was 15 months. In group 2, HGD was eradicated in one patient (100%), LGD in three patients (64%). A complete response was achieved in eight patients, partial response in four cases (77%). Mean follow-up was 10 months. The complication rate for groups 1 and 2 was of 18% and 10% respectively. No complication prevented completion of treatment or continued monitoring. Recurrence was evaluated to 5% in both groups.

CONCLUSION

RFA associated with EMR is feasible, offering probably better results and a very important advantage: a more complete histology before follow-up. Our results show effective treatment of BO and associated dysplasia with a low rate of complication. Nevertheless, when new techniques of BO ablation are used, the need to obtain histology before treatment should not be forgotten.

Endotherapy for Barrett's esophagus

Endotherapy is now the mainstay of therapy for Barrett's associated neoplasia. The approach should begin with confirmation of neoplasia by a gastrointestinal pathologist, patient counseling, and appropriate endoscopic work up. Detailed examination with high-resolution white light endoscopy is the most important tool for detection of neoplasia. Further validation studies are needed for many enhanced imaging modalities before being recommended as part of the standard work up and assessment of patients with Barrett's esophagus (BE). Endoscopic mucosal resection is required for any visible lesion in the setting of dysplasia for accurate histological diagnosis. The remainder of the epithelium may be treated with resection or ablative therapy, followed by adequate surveillance. Patients with nondysplastic Barrett's require further risk stratification before incorporation of ablative therapy for this population. The future will fortify the endoscopic role in Barrett's with validation trials for endoscopic assessment, further long-term results for each of the treatment modalities, potential risk stratification for patients with BE, and improved guidelines for surveillance after therapy.

Clinical implications of molecular changes in pediatric Barrett's esophagus

Barrett's esophagus (BE) is a preneoplastic condition that predisposes to esophageal adenocarcinoma. Although data on the occurrence of BE in children are limited, recent studies have suggested an increase in the pediatric population. BE is thought to be a complex disease in which individual genetic predisposition interacts with environmental stimuli. Early premalignant clones produce biological and genetic heterogeneity, resulting in stepwise changes in differentiation, proliferation, and apoptosis, allowing disease progression under selective pressure. The value of endoscopic surveillance biopsy for dysplasia and carcinoma in patients with BE is controversial. Thus, the recognition of early and objective alternative risk markers, less susceptible of sampling error, will be of relevance in the management of BE patients. The possibility of performing molecular genetics on paraffin-embedded biopsies will expand our understanding of the natural history of BE and may lead to the use of biomarkers to inform treatment strategies.

Biomarkers in exploring the frontiers of diagnosis, prognosis, and therapy of Barrett's esophagus

Barrett's esophagus (BE) is the principal risk factor for esophageal adenocarcinoma. BE patients currently undergo periodic endoscopic surveillance with tissue sampling and histopathologic assessment for dysplasia. They frequently are prescribed proton pump inhibitors to pharmacologically suppress gastric acid that is the cause of BE. These standard endoscopic and pharmacologic approaches for managing BE are crude at best. Identification of novel tissue biomarkers within BE may allow for more accurate endoscopic risk stratification and provide potential targets for chemoprevention.

Comparison of nuclear texture analysis and image cytometric DNA analysis for the assessment of dysplasia in Barrett's oesophagus

Background:

Dysplasia is a marker of cancer risk in Barrett's oesophagus (BO), but this risk is variable and diagnosis is subject to inter-observer variability. Cancer risk in BO is increased when chromosomal instability is present. Nucleotyping (NT) is a new method that uses high-resolution digital images of nuclei to assess chromatin organisation both quantitatively and qualitatively. We aimed to evaluate NT as a marker of dysplasia in BO and compare with image cytometric DNA analysis (ICM).

Methods:

In all, 120 patients with BO were studied. The non-dysplastic group (n=60) had specialised intestinal metaplasia only on two consecutive endoscopies after 51 months median follow-up (IQR=25–120 months). The dysplastic group (n=60) had high-grade dysplasia or carcinoma in situ. The two groups were then randomly assigned to a training set and a blinded test set in a 1 : 1 ratio. Image cytometric DNA analysis and NT was then carried out on Feulgen-stained nuclear monolayers.

Results:

The best-fit model for NT gave a correct classification rate (CCR) for the training set of 83%. The test set was then analysed using the same textural features and yielded a CCR of 78%. Image cytometric DNA analysis alone yielded a CCR of 73%. The combination of ICM and NT yielded a CCR of 84%.

Conclusion:

Nucleotyping differentiates dysplastic and non-dysplastic BO, with a greater sensitivity than ICM. A combination score based on both techniques performed better than either test in isolation. These data demonstrate that NT/ICM on nuclear monolayers is a very promising single platform test of genomic instability, which may aid pathologists in the diagnosis of dysplasia and has potential as a biomarker in BO.

Is endoscopic surveillance for non-dysplastic Barrett's esophagus cost-effective? Review of economic evaluations

BACKGROUND AND AIM

  Several health economic evaluations have explored the cost-effectiveness of endoscopic surveillance for patients with non-dysplastic Barrett's esophagus, with conflicting results. By comparing results across studies and highlighting key methodological and data limitations a platform for future, more rigorous analyses, can be developed.

METHODS

  A systematic literature review was undertaken of studies evaluating cost-effectiveness of surveillance for non-dysplastic Barrett's esophagus. Articles were included if they assessed both cost and health outcomes for surveillance versus no surveillance. A descriptive review was undertaken and the quality of the studies appraised against best-practice recommendations for economic evaluations and modeling studies.

RESULTS

  Seven publications met the inclusion criteria. All used decision-analytic Markov models. Half of the evaluations found surveillance was not cost-effective. At best, surveillance produced improved outcomes at a cost of US$16 640 per quality-adjusted life-year, and at worst it did more harm than good and at a greater cost. The quality of the evaluations and generalizability to the Asia-Pacific region was diminished as a result of inadequate or inconsistent evidence supporting parameter estimates, such as quality of life, endoscopic sensitivity and specificity and cancer recurrence rates.

CONCLUSIONS

  Unless newly emerging technologies improve the quality-adjusted survival benefit conferred by endoscopic surveillance, this strategy is unlikely to be cost-effective. Obsolete assumptions and incomplete analyses reduce the quality of published evaluations. For these reasons new evaluations are required that encompass the growing evidence base for new technologies, such as new endoscopic therapies for high-grade dysplasia and intramucosal cancer.

Barrett's esophagus: A historical perspective, an update on core practicalities and predictions on future evolutions of management

Interpretation of exploding knowledge about Barrett's esophagus is impaired by use of several conflicting definitions. Because any histological type of esophageal columnar metaplasia carries risk for esophageal adenocarcinoma, the diagnosis of Barrett's esophagus should no longer require demonstration of intestinal-type metaplasia. Endoscopic recognition and grading of Barrett's esophagus remains a significant source of ambiguity. Reflux disease is a key factor for development of Barrett's esophagus, but other factors must underlie its development, since it occurs in only a minority of reflux disease patients. Neither antireflux surgery nor proton pump inhibitor (PPI) therapy has major impacts on cancer risk. Within a year, a major trial should indicate whether low-dose aspirin usefully reduces cancer risk. The best referral centers have transformed the accuracy of screening and surveillance for early curable esophageal adenocarcinoma by use of enhanced and novel endoscopic imaging, visually-guided, rather than blind biopsies and by partnership with expert pathologists. General endoscopists now need to upgrade their skills and equipment so that they can rely mainly on visual targeting of biopsies on mucosal areas of concern in their surveillance practice. General pathologists need to greatly improve their interpretation of biopsies. Endoscopic therapy now achieves very high rates of cure of high-grade dysplasia and esophageal adenocarcinoma with minimal morbidity and risk. Such results will only be achieved by skilled interventional endoscopists. Esophagectomy should now be mainly restricted to patients whose cancer has extended into and beyond the submucosa. Weighing risks and benefits in the management of Barrett's esophagus is difficult, as is the process of adequately informing patients about their specific cancer risk.

A study of indefinite for dysplasia in Barrett's oesophagus: reproducibility of diagnosis, clinical outcomes and predicting progression with AMACR (alpha-methylacyl-CoA-racemase)

AIMS

To assess interobserver variation in the diagnosis of dysplasia in Barrett's oesophagus, especially indefinite dysplasia (IND) using the revised Vienna classification. A secondary aim was to study clinical outcome of IND cases and to evaluate expression of alpha-methyl-CoA racemase (AMACR) as a marker predictive of progression.

METHODS AND RESULTS

Cases of Barrett's oesophagus and dysplasia over a 20 year period were assessed. Three experienced histopathologists reviewed 101 cases on set criteria in a blinded fashion. Slides were immunostained for AMACR and evaluated for the presence, extent and location of AMACR expression. Clinical and progression data were collected. Overall agreement for the diagnosis of dysplasia was fair (k = 0.35) but that for IND was poor (k = 0.18). 6 IND cases progressed after a median follow-up of 31.4 months to a higher grade. The sensitivity of AMACR for the detection of abnormality was 22% for IND and specificity 100%. The positive predictive value of AMACR for progression was 0.44 and the negative predictive value was 0.92.

CONCLUSION

Fair agreement was achieved for the diagnosis of dysplasia but poor agreement for IND. A proportion of IND cases progress. Re-diagnosis or consensus diagnosis did not predict progression. AMACR shows promise as a marker to indicate IND patients in need of more intensive surveillance.

Esophageal resection for high-grade dysplasia and intramucosal carcinoma: When and how?

High-grade dysplasia (HGD) and intramucosal carcinoma (IMC) in the setting of Barrett’s esophagus have traditionally been treated with esophagectomy. However, with the advent of endoscopic mucosal resection and endoscopic ablative therapies, endoscopic therapy at centers with expertise is now an established treatment of Barrett’s-esophagus-related neoplasia, including HGD and IMC. Esophagectomy is today reserved for more selected cases with submucosal invasion, evidence for lymph node metastasis, or unsuccessful endoscopic therapy.

Pathophysiology and treatment of Barrett’s esophagus

Gastroesophageal reflux disease (GERD) affects an estimated 20% of the population in the United States. About 10%-15% of patients with GERD develop Barrett’s esophagus, which can progress to adenocarcinoma, currently the most prevalent type of esophageal cancer. The esophagus is normally lined by squamous mucosa, therefore, it is clear that for adenocarcinoma to develop, there must be a sequence of events that result in transformation of the normal squamous mucosa into columnar epithelium. This sequence begins with gastroesophageal reflux, and with continued injury metaplastic columnar epithelium develops. This article reviews the pathophysiology of Barrett’s esophagus and implications for its treatment. The effect of medical and surgical therapy of Barrett’s esophagus is compared.

Predictors of progression in Barrett's esophagus: current knowledge and future directions

Barrett's esophagus (BE) is the strongest risk factor for esophageal adenocarcinoma (EAC), a malignancy with persistently poor long-term outcomes. EAC is thought to develop through progression of metaplasia to dysplasia to invasive carcinoma. Identification of factors predicting progression to EAC would help in focusing surveillance, chemoprevention, or ablation for those deemed to be at highest risk of progression. We performed a comprehensive review of the literature and summarized current evidence on risk factors for progression in subjects with known BE. Clinical and demographic factors (age, male gender, length of BE segment) are associated with modestly increased odds of progression to EAC in some studies. Biomarkers such as aneuploidy and p53 loss of heterozygosity have been associated with increased risk of progression to high-grade dysplasia and/or EAC in single-center prospective cohort studies. Promising newer techniques and markers have been recently reported with the potential to help risk stratify BE subjects. Development of a comprehensive BE risk progression score comprised of both clinical and biomarker variables should be the ultimate goal and can be achieved by multicenter prospective collaborative efforts. Although it would be challenging, creation of such a score has the potential to improve outcomes and make the management of patients with BE more cost-effective.