Development and Validation of a Model to Determine Risk of Progression of Barrett's Esophagus to Neoplasia

Endoscopy and Barrett's Esophagus: Current Perspectives in the US and Japan

Barrett's esophagus (BE) is a precancerous disease that can lead to esophageal adenocarcinoma (EAC). Recently, the incidence of EAC arising from BE has been increasing, and EAC has now become a threat in many countries. However, there are many gaps among the various countries in terms of definitions and concepts and these gaps prevent discussing BE on the same footing. In order to eradicate BE, it is a global necessity to fill in these remaining gaps. We focused on the gaps and reviewed recent evidence and trends as well as the background of gaps between the US and Japan as two of the leading countries in the field of medical research. We also review the rapid advances in endoscopic techniques in relation to both diagnosis and therapy that are considered to be useful to eliminate the gaps between countries.

Epidemiology of Barrett's Esophagus and Esophageal Adenocarcinoma: Implications for Screening and Surveillance

In the United States, the incidence of esophageal adenocarcinoma increased markedly since the 1970s with a recent stabilization. Despite evolving screening and surveillance strategies to diagnose, risk triage, and intervene in Barrett's esophagus patients to prevent esophageal adenocarcinoma, most cases present with advanced disease and poor resultant survival. Epidemiologic studies have identified the main risk factors for these conditions, including increasing age, male sex, white race, gastroesophageal reflux disease, abdominal obesity, cigarette smoking, and lack of infection with Helicobacter pylori. This review summarizes the current epidemiologic evidence with implications for screening and surveillance in Barrett's esophagus and esophageal adenocarcinoma.

Reduced Esophageal Contractility Is Associated with Dysplasia Progression in Barrett's Esophagus: A Multicenter Cohort Study

BACKGROUND

The incidence of Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) continues to rise, and risk stratification of patients with BE is needed. Impaired esophageal motility is associated with gastroesophageal reflux disease; however, whether esophageal dysmotility is a risk factor for dysplasia progression in BE is incompletely understood. This study aimed to characterize esophageal motility patterns in patients with BE and identify physiologic factors associated with dysplasia progression in BE.

METHODS

This multicenter retrospective study assessed data from adult patients with histologically confirmed BE who underwent high-resolution esophageal manometry from 1/2014 to 1/2018 at four tertiary care centers. Longitudinal data were collected when available among patients with non-dysplastic BE (NDBE) and separated as: no dysplastic progression or positive dysplastic progression. Multivariable logistic regression assessed for independent predictors of dysplasia progression.

RESULTS

Among 193 patients, histology at index endoscopy identified 152 (79%) NDBE, 23 (12%) low-grade dysplasia, 14 (7%) high-grade dysplasia, and 4 (2%) EAC. Ninety-eight (51%) had abnormal esophageal motor function on manometry. Longitudinal data were available for 84 of 152 patients with initial NDBE. Twelve (14%) exhibited dysplastic progression to low-grade (6) or high-grade (6) dysplasia. Mean esophageal distal contractile integral was lower for patients that progressed [455 mmHg s cm (SD 515)] compared with patients who did not progress [987 mmHg s cm (SD 953); aOR 1.21 (95% CI 1.01, 1.44)].

CONCLUSION

In this retrospective study of 193 BE patients, the majority exhibited abnormal esophageal motor function. Reduced esophageal contractility was independently associated with dysplastic progression in BE. Characterizing esophageal physiology in BE may help to risk stratify patients.

Systematic review of the published guidelines on Barrett's esophagus: should we stress the consensus or the differences?

Multiple guidelines on Barrett's esophagus (BE) have being published in order to standardize and improve clinical practice. However, studies have shown poor adherence to them. Our aim was to synthetize, compare, and assess the quality of recommendations from recently published guidelines, stressing similarities and differences. We conducted a search in Pubmed and Scopus. When different guidelines from the same society were identified, the most recent one was considered. We used the GRADE system to assess the quality of evidence. We included 24 guidelines and position/consensus statements from the European Society of Gastrointestinal Endoscopy, British Society of Gastroenterology, American Society for Gastrointestinal Endoscopy, American Gastroenterological Association, American College of Gastroenterology, Australian guidelines, and Asia-Pacific consensus. All guidelines defend that BE should be diagnosed when there is an extension of columnar epithelium into the distal esophagus. However, there is still some controversy regarding length and histology criteria for BE diagnosis. All guidelines recommend expert pathologist review for dysplasia diagnosis. All guidelines recommend surveillance for non-dysplastic BE, and some recommend surveillance for indefinite dysplasia. While the majority of guidelines recommend ablation therapy for low-grade dysplasia without visible lesion, others recommend ablation therapy or endoscopic surveillance. However, controversy exists regarding surveillance intervals and biopsy protocols. All guidelines recommend endoscopic resection followed by ablation therapy for neoplastic visible lesion. Several guidelines use the GRADE system, but the majority of recommendations are based on low and moderate quality of evidence. Although there is considerable consensus among guidelines, there are some discrepancies resulting from low-quality evidence. The lack of high-quality evidence for the majority of recommendations highlights the importance of continued well-conducted research in this field.

Practical early cancer detection: distinguishing stable from unstable genomes in pre-cancerous tissues

Barrett’s oesophagus has been known for many years to display early changes to the genome consistent with the risk for oesophageal adenocarcinoma. Recently we have shown that this information can be used without knowledge of individual gene mutations to accurately predict a patient’s future risk of malignant progression.

An Analysis of the GIQuIC Nationwide Quality Registry Reveals Unnecessary Surveillance Endoscopies in Patients With Normal and Irregular Z-Lines

INTRODUCTION

Population-based estimates of adherence to Barrett's esophagus (BE) guidelines are not available. Using a national registry, we assessed surveillance intervals for patients with normal and irregular Z-lines based on the presence or absence of intestinal metaplasia (IM) and among patients with suspected or confirmed BE.

METHODS

We analyzed data from the GI Quality Improvement Consortium Registry. Endoscopy data, including procedure indication, demographics, endoscopy and histology findings, and recommendations for further endoscopy, were assessed from January 2013 through December 2019. Patients with an indication of BE screening or surveillance or an endoscopic finding of BE were included. Biopsy and surveillance practices were assessed based on the length of columnar epithelium (0 cm, <1 cm, 1-3 cm, and >3 cm) and diagnosis based on histology findings.

RESULTS

A total of 1,907,801 endoscopies were assessed; 135,704 endoscopies (7.1%) performed in 114,894 patients met the inclusion criteria (men 61.4%, Whites 91%, and mean age of 61.7 years [SD 12.5]). Among patients with normal Z-lines, surveillance endoscopy was recommended for 81% of patients with IM and 20% of individuals without IM. Among patients with irregular Z-lines, surveillance endoscopy was recommended for 81% with IM and 24% without IM. Approximately 30% of patients with confirmed nondysplastic BE (lengths 1-3 and >3 cm) had recommended surveillance intervals of <3 years.

DISCUSSION

An analysis of data from a nationwide quality registry demonstrated that patients without BE are receiving recommendations for surveillance endoscopies and many patients with nondysplastic BE are reexamined too soon.

Is Malignant Potential of Barrett's Esophagus Predictable by Endoscopy Findings?

Given that endoscopic findings can be used to predict the potential of neoplastic progression in Barrett's esophagus (BE) cases, the detection rate of dysplastic Barrett's lesions may become higher even in laborious endoscopic surveillance because a special attention is consequently paid. However, endoscopic findings for effective detection of the risk of neoplastic progression to esophageal adenocarcinoma (EAC) have not been confirmed, though some typical appearances are suggestive. In the present review, endoscopic findings that can be used predict malignant potential to EAC in BE cases are discussed. Conventional results obtained with white light endoscopy, such as length of BE, presence of esophagitis, ulceration, hiatal hernia, and nodularity, are used as indicators of a higher risk of neoplastic progression. However, there are controversies in some of those findings. Absence of palisade vessels may be also a new candidate predictor, as that reveals degree of intense inflammation and of cyclooxygenase-2 protein expression with accelerated cellular proliferation. Furthermore, an open type of mucosal pattern and enriched stromal blood vessels, which can be observed by image-enhanced endoscopy, including narrow band imaging, have been confirmed as factors useful for prediction of neoplastic progression of BE because they indicate more frequent cyclooxygenase-2 protein expression along with accelerated cellular proliferation. Should the malignant potential of BE be shown predictable by these endoscopic findings, that would simplify methods used for an effective surveillance, because patients requiring careful monitoring would be more easily identified. Development in the near future of a comprehensive scoring system for BE based on clinical factors, biomarkers and endoscopic predictors is required.

Genomic copy number predicts esophageal cancer years before transformation

Recent studies show that aneuploidy and driver gene mutations precede cancer diagnosis by many years^1-4. We assess whether these genomic signals can be used for early detection and pre-emptive cancer treatment using the neoplastic precursor lesion Barrett's esophagus as an exemplar⁵. Shallow whole-genome sequencing of 777 biopsies, sampled from 88 patients in Barrett's esophagus surveillance over a period of up to 15 years, shows that genomic signals can distinguish progressive from stable disease even 10 years before histopathological transformation. These findings are validated on two independent cohorts of 76 and 248 patients. These methods are low-cost and applicable to standard clinical biopsy samples. Compared with current management guidelines based on histopathology and clinical presentation, genomic classification enables earlier treatment for high-risk patients as well as reduction of unnecessary treatment and monitoring for patients who are unlikely to develop cancer.

What is the optimal surveillance strategy for non-dysplastic Barrett's esophagus?

PURPOSE OF REVIEW

There is conflicting data on the effectiveness of the currently recommended endoscopic surveillance strategy in non-dysplastic BE patients. We reviewed the literature to evaluate the (cost) effectiveness of the current surveillance strategy. We also reviewed critical strategies and new technologies which could improve dysplasia detection.

RECENT FINDINGS

Adherence to the current EGD surveillance guidelines is suboptimal with high rates of missed dysplasia/EAC. The influence of surveillance on EAC mortality appears modest. Careful cleansing, inspection and sampling of the BE mucosa using high resolution while light and (electronic) chromoendoscopy is critical. Newer sampling techniques coupled with computer aided diagnosis and emerging imaging technologies have shown promise in improving dysplasia detection. Personalized surveillance with risk stratification based on risk factors for progression may be on the horizon.

SUMMARY

Current BE surveillance strategy will likely be further refined and optimized by emerging new technologies in tissue sampling, advanced imaging and risk stratification.

A narrative review of Barrett's esophagus in 2020, molecular and clinical update

Barrett’s esophagus (BE) is a condition resulting from an acquired metaplastic epithelial change in the esophagus in response to gastroesophageal reflux. BE is the only known precursor lesion to esophageal adenocarcinoma, and can progress from non-dysplastic BE (NDBE) to low grade dysplasia (LGD) and high grade dysplasia (HGD), and ultimately invasive carcinoma. Although the risk of developing esophageal adenocarcinoma (EAC) in NBDE is less than 0.5% per year, there has been a rising incidence of EAC in Western countries, which continue to drive efforts to optimize screening and surveillance methods. The current gold standard for diagnosis is esophagogastroduodenoscopy (EGD), and there has been significant interest in alternative, minimally invasive methods for screening which would be more readily accessible in the primary care setting. Surveillance endoscopy in 3–5 years is recommended for NDBE given the low progression to EAC. The mainstay of treatment for LGD and HGD is endoscopic eradication therapy (EET). Visible lesions are treated with endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD). Radiofrequency ablation (RFA) is considered first line therapy for flat dysplastic BE and cryotherapy has shown promising results as an alternate form of treatment for of dysplasia. The molecular progression of BE to EAC is a complex process involving multiple pathways involving genetic and epigenetic modifications. Genomic studies have further led to the understanding of the complex molecular landscape that occurs early and late in the disease process. Promising biomarker panels have been investigated to help with the diagnosis of BE as well as aid in the risk stratification of BE during surveillance. In addition, clinical prediction models have been developed to categorize BE patients in low, intermediate, and high risk for progression to HGD and EAC. Further clinical and translational research is needed to help refine markers and techniques in diagnosis, screening, and surveillance.

The role of esophagectomy in the management of Barrett's esophagus with high-grade dysplasia

Barrett's esophagus (BE) with high-grade dysplasia (HGD) has previously been a routine indication for esophagectomy. Recent advances in endoscopic therapy have resulted in a shift away from surgery. Current international guidelines recommend endoscopic therapy for BE with HGD irrespective of recurrence or progression of dysplasia. Current guidelines do not address the ongoing role of esophagectomy as an adjunct in the setting of failed endoscopic therapy. This review examines the role of esophagectomy as an adjunct to endoscopy in the management of patients with BE and HGD, with a specific focus on patients with persistent, progressive, or recurrent disease, disease resistant to endoscopic therapy, in patients with concomitant esophageal pathology, and in those patients in whom lifelong surveillance may not be possible or desired.

Individuals' Preferences for Esophageal Cancer Screening: A Discrete Choice Experiment

OBJECTIVES

The increasing incidence of esophageal adenocarcinoma (EAC) and the dismal prognosis has stimulated interest in the early detection of EAC. Our objective was to determine individuals' preferences for EAC screening and to assess to what extent procedural characteristics of EAC screening tests predict willingness for screening participation.

METHODS

A discrete choice experiment questionnaire was sent by postal mail to 1000 subjects aged 50 to 75 years who were randomly selected from the municipal registry in the Netherlands. Each subject answered 12 discrete choice questions of 2 hypothetical screening tests comprising 5 attributes: EAC-related mortality risk reduction, procedure-related pain and discomfort, screening location, test specificity, and costs. A multinomial logit model was used to estimate individuals' preferences for each attribute level and to calculate expected rates of uptake.

RESULTS

In total, 375 individuals (37.5%) completed the questionnaire. Test specificity, pain and discomfort, mortality reduction, and out-of-pocket costs all had a significant impact on respondents' preferences. The average expected uptake of EAC screening was 62.8% (95% confidence interval [CI] 61.1-64.5). Severe pain and discomfort had the largest impact on screening uptake (-22.8%; 95% CI -26.8 to -18.7). Male gender (β 2.81; P < .001), cancer worries (β 1.96; P = .01), endoscopy experience (β 1.46; P = .05), and upper gastrointestinal symptoms (β 1.50; P = .05) were significantly associated with screening participation.

CONCLUSIONS

EAC screening implementation should consider patient preferences to maximize screening attendance uptake. Based on our results, an optimal screening test should have high specificity, cause no or mild to moderate pain or discomfort, and result in a decrease in EAC-related mortality.

Recent insights into the biology of Barrett's esophagus

Barrett's esophagus (BE) is the only known precursor to esophageal adenocarcinoma (EAC), an aggressive cancer with a poor prognosis. Our understanding of the pathogenesis and Barrett's metaplasia is incomplete, and this has limited the development of new therapeutic targets and agents, risk stratification ability, and management strategies. This review outlines current insights into the biology of BE and addresses controversies surrounding cell of origin, cellular reprogramming theories, updates on esophageal epithelial barrier function, and the significance of goblet cell metaplasia and its association with malignant change. Further research into the basic biology of BE is vital as it will underpin novel therapies and improve our ability to predict malignant progression and help identify the minority of patients who will develop EAC.

Independent Blinded Validation of a Tissue Systems Pathology Test to Predict Progression in Patients With Barrett's Esophagus

INTRODUCTION

A risk prediction test was previously validated to predict progression to high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) in patients with Barrett's esophagus (BE). The aim of our study was to independently validate this test to predict the risk of progression to HGD/EAC in BE patients with nondysplastic (ND), indefinite for dysplasia and low-grade dysplasia (LGD).

METHODS

A single-blinded, case-control study was conducted to stratify patients with BE as low, intermediate, or high risk for progression to HGD/EAC within 5 years using a previously described risk prediction test. Patients with BE who progressed to HGD/EAC after at least 1 year (n = 58) were matched to patients undergoing surveillance without progression (n = 210, median surveillance 7 years). Baseline biopsies with subspecialist diagnoses of ND, indefinite for dysplasia, or LGD were tested in a blinded manner, and the predictive performance of the test was assessed.

RESULTS

This risk prediction test stratified patients with BE based on progression risk with the high-risk group at 4.7-fold increased risk for HGD/EAC compared with the low-risk group (95% confidence interval 2.5-8.8, P < 0.0001). Prevalence-adjusted positive predictive value at 5 years was 23%. The high-risk class and male sex provided predictive power that was independent of pathologic diagnosis, age, segment length, and hiatal hernia. Patients with ND BE who scored high risk progressed at a higher rate (26%) than patients with subspecialist-confirmed LGD (21.8%) at 5 years.

DISCUSSION

A risk prediction test identifies patients with ND BE who are at high risk for progression to HGD/EAC and may benefit from early endoscopic therapy or increased surveillance.

Predicting Progression in Barrett's Esophagus: Is the Holy Grail Within Reach?

Risk stratification in Barrett's esophagus may allow aggressive management of those at "high risk" and reduction in surveillance in at "low" risk. Davison et al. report the results of the independent validation of a multibiomarker panel (TissueCypher assay) performed on biopsy tissue, in a case control study. "High-risk" patients progressed 5 times more than those at "low risk." Sensitivity and specificity for "high-risk" patients were 29% and 86% with a positive predictive value of 23%. A negative predictive value of a "low-risk" score was 96%. These findings may allow more intensive surveillance in those at "high risk." Despite some limitations, this assay is a potentially major advance in the management of Barrett's esophagus patients without dysplasia.

Indications, contraindications and limitations of endoscopic therapy for Barrett's esophagus and early esophageal adenocarcinoma

Endoscopic eradication therapy (EET) has revolutionized management of Barrett's esophagus (BE)-associated neoplasia, traditionally treated by esophagectomy, which carries very high mortality and morbidity. EET, usually performed in the outpatient setting, has a safe risk profile. It is indicated in patients with BE with high-grade dysplasia and intramucosal cancer, confirmed, and persistent low-grade dysplasia, and in highly selected cases of non-dysplastic BE and submucosal cancers. Multiple EET modalities are available and can be categorized into two groups: ablation therapies and resection techniques with resection techniques usually reserved for nodular/raised lesions or lesions with suspected neoplasia. Patients usually require multiple ablation sessions with a goal of achieving complete eradication of metaplasia. Despite very good results, EET has its limitations and is not 100% effective: it targets a small subset of patients along the spectrum of BE and esophageal adenocarcinoma, as most patients with esophageal adenocarcinoma remain asymptomatic until the disease has progressed to advanced stages. Post-ablation surveillance is mandatory, as recurrences are common. An area of concern is buried metaplasia reported to occur following ablation therapy and thought to be from de novo growth of metaplastic tissue underneath the neosquamous epithelium, following ablation. The focus of this review article is to present the indications, contraindications and limitations of EET.

Aneuploidy in targeted endoscopic biopsies outperforms other tissue biomarkers in the prediction of histologic progression of Barrett's oesophagus: A multi-centre prospective cohort study

Background

The cancer risk in Barrett's oesophagus (BO) is difficult to estimate. Histologic dysplasia has strong predictive power, but can be missed by random biopsies. Other clinical parameters have limited utility for risk stratification. We aimed to assess whether a molecular biomarker panel on targeted biopsies can predict neoplastic progression of BO.

Methods

203 patients with BO were tested at index endoscopy for 9 biomarkers (p53 and cyclin A expression; aneuploidy and tetraploidy; CDKN2A (p16), RUNX3 and HPP1 hypermethylation; 9p and 17p loss of heterozygosity) on autofluorescence-targeted biopsies and followed-up prospectively. Data comparing progressors to non-progressors were evaluated by univariate and multivariate analyses using survival curves, Cox-proportional hazards and logistic regression models.

Findings

127 patients without high-grade dysplasia (HGD) or oesophageal adenocarcinoma (OAC) at index endoscopy were included, of which 42 had evidence of any histologic progression over time. Aneuploidy was the only predictor of progression from non-dysplastic BO (NDBO) to any grade of neoplasia (p = 0.013) and HGD/OAC (p = 0.002). Aberrant p53 expression correlated with risk of short-term progression within 12 months, with an odds ratio of 6.0 (95% CI: 3.1–11.2). A panel comprising aneuploidy and p53 had an area under the receiving operator characteristics curve of 0.68 (95% CI: 0.59–0.77) for prediction of any progression.

Interpretation

Aneuploidy is the only biomarker that predicts neoplastic progression of NDBO. Aberrant p53 expression suggests prevalent dysplasia, which might have been missed by random biopsies, and warrants early follow up.

Epidemiologic Risk Factors in a Comparison of a Barrett Esophagus Registry (BarrettNET) and a Case-Control Population in Germany

Endoscopic screening for Barrett's esophagus as the major precursor lesion for esophageal adenocarcinoma is mostly offered to patients with symptoms of gastroesophageal reflux disease (GERD). However, other epidemiologic risk factors might affect the development of Barrett's esophagus and esophageal adenocarcinoma. Therefore, efforts to improve the efficiency of screening to find the Barrett's esophagus population "at risk" compared with the normal population are needed. In a cross-sectional analysis, we compared 587 patients with Barrett's esophagus from the multicenter German BarrettNET registry to 1976 healthy subjects from the population-based German KORA cohort, with and without GERD symptoms. Data on demographic and lifestyle factors, including age, gender, smoking, alcohol consumption, body mass index, physical activity, and symptoms were collected in a standardized epidemiologic survey. Increased age, male gender, smoking, heavy alcohol consumption, low physical activity, low health status, and GERD symptoms were significantly associated with Barrett's esophagus. Surprisingly, among patients stratified for GERD symptoms, these associations did not change. Demographic, lifestyle, and clinical factors as well as GERD symptoms were associated with Barrett's esophagus development in Germany, suggesting that a combination of risk factors could be useful in developing individualized screening efforts for patients with Barrett's esophagus and GERD in Germany.

Barrett Esophagus

Barrett esophagus is a metaplastic change in the lining of the distal esophageal epithelium, characterized by replacement of the normal squamous epithelium by specialized intestinal metaplasia. The presence of Barrett esophagus increases the risk of esophageal adenocarcinoma several-fold. Esophageal adenocarcinoma is a malignancy with rapidly rising incidence and persistently poor outcomes when diagnosed after the onset of symptoms. Risk factors for Barrett esophagus include chronic gastroesophageal reflux, central obesity, white race, male gender, older age, smoking, and a family history of Barrett esophagus or esophageal adenocarcinoma. Screening for Barrett esophagus in those with several risk factors followed by endoscopic surveillance to detect dysplasia or adenocarcinoma is currently recommended by society guidelines. Minimally invasive nonendoscopic tools for the early detection of Barrett esophagus are currently being developed. Multimodality endoscopic therapy-using a combination of endoscopic resection and ablation techniques-for the treatment of dysplasia and early adenocarcinoma is successful in eliminating intestinal metaplasia and preventing progression to adenocarcinoma, with outcomes comparable to those after esophagectomy. Risk stratification of those diagnosed with Barrett esophagus is a challenge at present, with active research focused on identifying clinical and biomarker panels to identify those with low and high risk of progression. This narrative review highlights some of the challenges and recent progress in this field.

What Quality Metrics Should We Apply in Barrett's Esophagus?

A GI Quality improvement consortium registry study published in this issue of The American Journal of Gastroenterology confirms the lack of adherence to surveillance intervals and guidelines in patients with Barrett's esophagus (BE). Given the widespread use of upper endoscopy for evaluation of patients with gastroesophageal reflux disease and surveillance of BE, the lack of well-defined standard criteria for performing a high quality upper endoscopy calls for the establishment of valid quality indicators in BE endoscopy. These quality metrics should be able to help define and rate endoscopist performance for screening, surveillance, and management of patients with BE. Neoplasia detection rate and Barrett's inspection time could serve as key benchmarks. The issue of nonadherence and overutilization of endoscopy can be addressed by continuing education, feedback, and incorporation of better healthcare models.

Interactive decision support for esophageal adenocarcinoma screening and surveillance

BACKGROUND

A key barrier to controlling esophageal adenocarcinoma (EAC) is identifying those most likely to benefit from screening and surveillance. We aimed to develop an online educational tool, termed IC-RISC™, for providers and patients to estimate more precisely their absolute risk of developing EAC, interpret this estimate in the context of risk of dying from other causes, and aid in decision-making.

RESULTS

U.S. incidence and mortality data and published relative risk estimates from observational studies and clinical trials were used to calculate absolute risk of EAC over 10 years adjusting for competing risks. These input parameters varied depending on presence of the key precursor, Barrett's esophagus. The open source application works across common devices to gather risk factor data and graphically illustrate estimated risk on a single page. Changes to input data are immediately reflected in the colored graphs. We used the calculator to compare the risk distribution between EAC cases and controls from six population-based studies to gain insight into the discrimination metrics of current practice guidelines for screening, observing that current guidelines sacrifice a significant amount of specificity to identify 78-86% of eventual cases in the US population.

CONCLUSIONS

This educational tool provides a simple and rapid means to graphically communicate risk of EAC in the context of other health risks, facilitates "what-if" scenarios regarding potential preventative actions, and can inform discussions regarding screening, surveillance and treatment options. Its generic architecture lends itself to being easily extended to other cancers with distinct pathways and/or intermediate stages, such as hepatocellular cancer. IC-RISC™ extends current qualitative clinical practice guidelines into a quantitative assessment, which brings the possibility of preventative actions being offered to persons not currently targeted for screening and, conversely, reducing unnecessary procedures in those at low risk. Prospective validation and application to existing well-characterized cohort studies are needed.

Barrett oesophagus

Barrett oesophagus (BE), the only known histological precursor of oesophageal adenocarcinoma (EAC), is a condition in which the squamous epithelium of the oesophagus is replaced by columnar epithelium as an adaptive response to gastro-oesophageal reflux. EAC has one of the fastest rising incidences of cancers in Western countries and has a dismal prognosis. BE is usually detected during endoscopic examination, and diagnosis is confirmed by the histological presence of intestinal metaplasia. Advances in genomics and transcriptomics have improved our understanding of the pathogenesis and malignant progression of intestinal metaplasia. As the majority of EAC cases are diagnosed in individuals without a known history of BE, screening for BE could potentially decrease disease-related mortality. Owing to the pre-malignant nature of BE, endoscopic surveillance of patients with BE is imperative for early detection and treatment of dysplasia to prevent further progression to invasive EAC. Developments in endoscopic therapy have resulted in a major shift in the treatment of patients with BE who have dysplasia or early EAC, from surgical resection to endoscopic resection and ablation. In addition to symptom control by optimization of lifestyle and pharmacological therapy with proton pump inhibitors, chemopreventive strategies based on NSAIDs and statins are currently being investigated for BE management.

Evolving screening and surveillance techniques for Barrett's esophagus

Barrett’s esophagus (BE) is a change in the esophageal lining and is known to be the major precursor lesion for most cases of esophageal adenocarcinoma (EAC). Despite an understanding of its association with BE for many years and the falling incidence rates of squamous cell carcinoma of the esophagus, the incidence for EAC continues to rise exponentially. In association with this rising incidence, if the delay in diagnosis of EAC occurs after the onset of symptoms, then the mortality at 5 years is greater than 80%. Appropriate diagnosis and surveillance strategies are therefore vital for BE. Multiple novel optical technologies and other advanced approaches are being utilized to assist in making screening and surveillance more cost effective. We review the current guidelines and evolving techniques that are currently being evaluated.

External validation of a model to determine risk of progression of Barrett's oesophagus to neoplasia

BACKGROUND

A risk prediction model containing sex, smoking history, Barrett's oesophagus length and presence of low-grade dysplasia was found to identify individuals at a higher risk of progression to oesophageal adenocarcinoma or high-grade dysplasia.

AIM

To externally validate the model predicting risk of progression from Barrett's oesophagus to neoplasia and assess the predictive utility of additional factors.

METHODS

We conducted a retrospective cohort study among individuals from the population-based Northern Ireland Barrett's register with a histologically confirmed diagnosis of Barrett's oesophagus (with intestinal metaplasia) between 1993 and 2005. The association between a points based model and risk of progression to high-grade dysplasia or oesophageal adenocarcinoma until 2010 was assessed using Cox Proportional Hazards model. Model performance was assessed using area under the receiver operating characteristics curves (AUROC), sensitivity and specificity.

RESULTS

We identified 1198 individuals with Barrett's oesophagus of whom 54 progressed. The model discriminated reasonably well between progressors and nonprogressors, with an AUROC of 0.70 (95% CI 0.63-0.78). When categorised into low, intermediate and high risk groups, the AUROC was 0.68 (95% CI 0.61-0.74). Compared to using data on dysplasia and segment length for risk stratification, the model resulted in a net reclassification improvement of 20.9%.

CONCLUSIONS

This external validation provides further evidence that a model based on sex, smoking, Barrett's segment length and baseline low-grade dysplasia may help to risk stratify patients after an initial diagnosis of Barrett's oesophagus. The model also performed better than the use of low-grade dysplasia status alone for risk-stratification.

Economic value of narrow-band imaging versus white light endoscopy for the diagnosis and surveillance of Barrett's esophagus: Cost-consequence model

Barrett’s esophagus (BE) is an abnormality arising from gastroesophageal reflux disease that can progressively evolve into a sequence of dysplasia and adenocarcinoma. Progression of Barrett’s esophagus into dysplasia is monitored with endoscopic surveillance. The current surveillance standard requests random biopsies plus targeted biopsies of suspicious lesions under white-light endoscopy, known as the Seattle protocol. Recently, published evidence has shown that narrow-band imaging (NBI) can guide targeted biopsies to identify dysplasia and reduce the need for random biopsies. We aimed to assess the health economic implications of adopting NBI-guided targeted biopsy vs. the Seattle protocol from a National Health Service England perspective. A decision tree model was developed to undertake a cost-consequence analysis. The model estimated total costs (i.e. staff and overheads; histopathology; adverse events; capital equipment) and clinical implications of monitoring a cohort of patients with known/suspected BE, on an annual basis. In the simulation, BE patients (N = 161,657 at Year 1; estimated annual increase: +20%) entered the model every year and underwent esophageal endoscopy. After 7 years, the adoption of NBI with targeted biopsies resulted in cost reduction of £458.0 mln vs. HD-WLE with random biopsies (overall costs: £1,966.2 mln and £2,424.2 mln, respectively). The incremental investment on capital equipment to upgrade hospitals with NBI (+£68.3 mln) was offset by savings due to the reduction of histological examinations (-£505.2 mln). Reduction of biopsies also determined savings for avoided adverse events (-£21.1 mln). In the base-case analysis, the two techniques had the same accuracy (number of correctly identified cases: 1.934 mln), but NBI was safer than HD-WLE. Budget impact analysis and cost-effectiveness analyses confirmed the findings of the cost-consequence analysis. In conclusion, NBI-guided targeted biopsies was a cost-saving strategy for NHS England, compared to current practice for detection of dysplasia in patients with BE, whilst maintaining at least comparable health outcomes for patients.

Recent advances in Barrett's esophagus

Barrett's esophagus (BE) is the only known precursor of esophageal adenocarcinoma, one of the few cancers with increasing incidence in developed countries. The pathogenesis of BE is unclear with regard to either the cellular origin of this metaplastic epithelium or the manner in which malignant transformation occurs, although recent data indicate a possible junctional origin of stem cells for BE. Treatment of BE may be achieved using endoscopic eradication therapy; however, there is a lack of discriminatory tools to identify individuals at sufficient risk for cancer development in whom intervention is warranted. Reduction in gastroesophageal reflux of gastric contents including acid is mandatory to achieve remission from BE after endoscopic ablation, and can be achieved using medical or nonmedical interventions. Research topics of greatest interest include the mechanism of BE development and transformation to cancer, risk stratification methods to identify individuals who may benefit from ablation of BE, optimization of eradication therapy, and surveillance methods to ensure that remission is maintained after eradication is achieved.

Natural History of Barrett's Esophagus

Barrett's esophagus (BE) is a very common condition. We have obtained fairly profound knowledge of the natural history of this condition. This results from many cross-sectional and cohort studies, many describing patients undergoing long-term surveillance. Their consent to use their clinical data has improved our knowledge to the benefit of these same and other patients. The prevalence of BE increases with age both in men and in women. This increase starts at a younger age in men than in women. The incidence of high-grade dysplasia and cancer in BE depends on segment length, gender, and age. The latter two likely indicate the duration of the presence of BE in an individual patient. Other factors that influence the incidence of dysplasia and cancer are smoking behavior and use of certain medications such as PPIs, statins, and NSAIDs. Surveillance of BE and treatment of dysplasia can impact the incidence of and mortality due to esophageal adenocarcinoma. This is of major benefit to a subgroup of BE patients. The epidemiology and burden of disease ask for further efforts to develop targeted screening, surveillance, and intervention techniques in coming years.