Do 40% of patients resected for barrett esophagus with high-grade dysplasia have unsuspected adenocarcinoma?

High Risk of Persistence and Risk of Dysplasia After Diagnosis of Ultrashort Barrett's Esophagus

INTRODUCTION

The management of ultrashort (<1 cm) Barrett's esophagus (BE) remains unclear. We aimed to determine the prevalence of ultrashort BE (USBE) at index diagnosis, identify factors associated with persistent BE after USBE diagnosis, and identify risk of dysplasia after initial USBE in a population of US veterans.

METHODS

This was a retrospective cohort study at the Veterans Affairs hospital in Houston, TX, of consecutive patients with new BE diagnosis from November 1990 to June 2022 with follow-up through April 2023. Using a pathology database, we identified patients with a new USBE diagnosis and any subsequent follow-up esophagogastroduodenoscopy (EGD). We examined the association of sociodemographic and clinical risk factors of persistent USBE cohort compared with longer-length segment BE and those with a negative follow-up EGD after index USBE with χ 2 tests and logistic regression models. Last, we calculated the prevalence and incidence of any dysplasia in persistent BE after USBE at index diagnosis compared with BE ≥1 cm. We excluded patients without at least 1 follow-up endoscopy.

RESULTS

Of 739 patients with BE, 167 (22.6%) had USBE on index EGD. Of those with index USBE, 86 (51.5%) had persistent BE and 67 (40.1%) had negative intestinal metaplasia on follow-up EGD. There was a greater proportion of non-Hispanic White and Hispanic than non-Hispanic Black patients with persistent BE after index USBE and the negative follow-up of EGD cohorts ( P = 0.012), but no significant difference in age, sex, smoking status, alcohol status, and body mass index between the 2 groups. White race (adjusted odds ratio [aOR] 3.80; 95% confidence interval [CI] 1.35-10.7) and Hispanic ethnicity (aOR 4.85; 95% CI 1.19-19.7; ref: non-Hispanic Black) were associated with an increased likelihood of persistent BE. During 3,880.7 person-years of follow-up, 112 patients (10 persistent BE after index USBE) developed definite dysplasia/neoplasia. The incidence rate of definite dysplasia/neoplasia was 19.5 per 1,000 person-years (95% CI 10.5-36.3 per 1,000 person-years) in those with persistent BE after USBE and 33.8 per 1,000 person-years (95% CI 27.9-41.1 per 1,000 person-years) in those with longer segment BE ( P value by log-rank test = 0.23; hazard ratio 0.67; 95% CI 0.35-1.29). We did not identify any significant predictors of dysplasia in persistent BE after index endoscopy with USBE.

DISCUSSION

The prevalence of persistent BE after index USBE is high, and there is a risk of developing dysplasia/neoplasia in persistent BE after USBE. We were unable to detect a difference in the risk of dysplasia/neoplasia between persistent BE after index USBE and BE ≥1 cm on index endoscopy in a cohort of US veterans. White race and Hispanic ethnicity are associated with persistent BE after index USBE and may be target demographics for surveillance.

Latest Advances in Endoscopic Detection of Oesophageal and Gastric Neoplasia

Endoscopy is the gold standard for the diagnosis of cancers and cancer precursors in the oesophagus and stomach. Early detection of upper GI cancers requires high-quality endoscopy and awareness of the subtle features these lesions carry. Endoscopists performing surveillance of high-risk patients including those with Barrett's oesophagus, previous squamous neoplasia or chronic atrophic gastritis should be familiar with endoscopic features, classification systems and sampling techniques to maximise the detection of early cancer. In this article, we review the current approach to diagnosis of these conditions and the latest advanced imaging and diagnostic techniques.

A new artificial intelligence system successfully detects and localises early neoplasia in Barrett's esophagus by using convolutional neural networks

BACKGROUND AND AIMS

Seattle protocol biopsies for Barrett's Esophagus (BE) surveillance are labour intensive with low compliance. Dysplasia detection rates vary, leading to missed lesions. This can potentially be offset with computer aided detection. We have developed convolutional neural networks (CNNs) to identify areas of dysplasia and where to target biopsy.

METHODS

119 Videos were collected in high-definition white light and optical chromoendoscopy with i-scan (Pentax Hoya, Japan) imaging in patients with dysplastic and non-dysplastic BE (NDBE). We trained an indirectly supervised CNN to classify images as dysplastic/non-dysplastic using whole video annotations to minimise selection bias and maximise accuracy. The CNN was trained using 148,936 video frames (31 dysplastic patients, 31 NDBE, two normal esophagus), validated on 25,161 images from 11 patient videos and tested on 264 iscan-1 images from 28 dysplastic and 16 NDBE patients which included expert delineations. To localise targeted biopsies/delineations, a second directly supervised CNN was generated based on expert delineations of 94 dysplastic images from 30 patients. This was tested on 86 i-scan one images from 28 dysplastic patients.

FINDINGS

The indirectly supervised CNN achieved a per image sensitivity in the test set of 91%, specificity 79%, area under receiver operator curve of 93% to detect dysplasia. Per-lesion sensitivity was 100%. Mean assessment speed was 48 frames per second (fps). 97% of targeted biopsy predictions matched expert and histological assessment at 56 fps. The artificial intelligence system performed better than six endoscopists.

INTERPRETATION

Our CNNs classify and localise dysplastic Barrett's Esophagus potentially supporting endoscopists during surveillance.

Advanced imaging and artificial intelligence for Barrett's esophagus: What we should and soon will do

Barrett's esophagus (BE) is a well-established risk factor for esophageal adenocarcinoma. It is recommended that patients have regular endoscopic surveillance, with the ultimate goal of detecting early-stage neoplastic lesions before they can progress to invasive carcinoma. Detection of both dysplasia or early adenocarcinoma permits curative endoscopic treatments, and with this aim, thorough endoscopic assessment is crucial and improves outcomes. The burden of missed neoplasia in BE is still far from being negligible, likely due to inappropriate endoscopic surveillance. Over the last two decades, advanced imaging techniques, moving from traditional dye-spray chromoendoscopy to more practical virtual chromoendoscopy technologies, have been introduced with the aim to enhance neoplasia detection in BE. As witnessed in other fields, artificial intelligence (AI) has revolutionized the field of diagnostic endoscopy and is set to cover a pivotal role in BE as well. The aim of this commentary is to comprehensively summarize present evidence, recent research advances, and future perspectives regarding advanced imaging technology and AI in BE; the combination of computer-aided diagnosis to a widespread adoption of advanced imaging technologies is eagerly awaited. It will also provide a useful step-by-step approach for performing high-quality endoscopy in BE, in order to increase the diagnostic yield of endoscopy in clinical practice.

Evolutionary dynamics in Barrett oesophagus: implications for surveillance, risk stratification and therapy

Cancer development is a dynamic evolutionary process characterized by marked intratumoural heterogeneity at the genetic, epigenetic and phenotypic levels. Barrett oesophagus, the pre-malignant condition to oesophageal adenocarcinoma (EAC), is an exemplary system to longitudinally study the evolution of malignancy. Evidence has emerged of Barrett oesophagus lesions pre-programmed for progression to EAC many years before clinical detection, indicating a considerable window for therapeutic intervention. In this Review, we explore the mechanisms underlying clonal expansion and contraction that establish the Barrett oesophagus clonal mosaicism over time and space and discuss intrinsic genotypic and extrinsic environmental drivers that direct the evolutionary trajectory of Barrett oesophagus towards a malignant phenotype. We propose that understanding and exploiting the evolutionary dynamics of Barrett oesophagus will identify novel therapeutic targets, improve prognostic tools and offer the opportunity for personalized surveillance programmes geared to prevent progression to EAC.

Barrett's esophagus: The pathomorphological and molecular genetic keystones of neoplastic progression

Barrett's esophagus is a widespread chronically progressing disease of heterogeneous nature. A life threatening complication of this condition is neoplastic transformation, which is often overlooked due to lack of standardized approaches in diagnosis, preventative measures and treatment. In this essay, we aim to stratify existing data to show specific associations between neoplastic transformation and the underlying processes which predate cancerous transition. We discuss pathomorphological, genetic, epigenetic, molecular and immunohistochemical methods related to neoplasia detection on the basis of Barrett's esophagus. Our review sheds light on pathways of such neoplastic progression in the distal esophagus, providing valuable insight into progression assessment, preventative targets and treatment modalities. Our results suggest that molecular, genetic and epigenetic alterations in the esophagus arise earlier than cancerous transformation, meaning the discussed targets can help form preventative strategies in at-risk patient groups.

Prospective development and validation of a volumetric laser endomicroscopy computer algorithm for detection of Barrett's neoplasia

BACKGROUND AND AIMS

Volumetric laser endomicroscopy (VLE) is an advanced imaging modality used to detect Barrett's esophagus (BE) dysplasia. However, real-time interpretation of VLE scans is complex and time-consuming. Computer-aided detection (CAD) may help in the process of VLE image interpretation. Our aim was to train and validate a CAD algorithm for VLE-based detection of BE neoplasia.

METHODS

The multicenter, VLE PREDICT study, prospectively enrolled 47 patients with BE. In total, 229 nondysplastic BE and 89 neoplastic (high-grade dysplasia/esophageal adenocarcinoma) targets were laser marked under VLE guidance and subsequently underwent a biopsy for histologic diagnosis. Deep convolutional neural networks were used to construct a CAD algorithm for differentiation between nondysplastic and neoplastic BE tissue. The CAD algorithm was trained on a set consisting of the first 22 patients (134 nondysplastic BE and 38 neoplastic targets) and validated on a separate test set from patients 23 to 47 (95 nondysplastic BE and 51 neoplastic targets). The performance of the algorithm was benchmarked against the performance of 10 VLE experts.

RESULTS

Using the training set to construct the algorithm resulted in an accuracy of 92%, sensitivity of 95%, and specificity of 92%. When performance was assessed on the test set, accuracy, sensitivity, and specificity were 85%, 91%, and 82%, respectively. The algorithm outperformed all 10 VLE experts, who demonstrated an overall accuracy of 77%, sensitivity of 70%, and specificity of 81%.

CONCLUSIONS

We developed, validated, and benchmarked a VLE CAD algorithm for detection of BE neoplasia using prospectively collected and biopsy-correlated VLE targets. The algorithm detected neoplasia with high accuracy and outperformed 10 VLE experts. (The Netherlands National Trials Registry (NTR) number: NTR 6728.).

Expert assessment on volumetric laser endomicroscopy full scans in Barrett's esophagus patients with or without high grade dysplasia or early cancer

BACKGROUND

Volumetric laser endomicroscopy (VLE) allows for near-microscopic imaging of the superficial esophageal wall and may improve detection of early neoplasia in Barrett's esophagus (BE). Interpretation of a 6-cm long, circumferential VLE "full scan" may however be challenging for endoscopists. We aimed to evaluate the accuracy of VLE experts in correctly diagnosing VLE full scans of early neoplasia and non-dysplastic BE (NDBE).

METHODS

29 VLE full scan videos (15 neoplastic and 14 NDBE) were randomly evaluated by 12 VLE experts using a web-based module. Experts were blinded to the endoscopic BE images and histology. The 15 neoplastic cases contained a subtle endoscopically visible lesion, which on endoscopic resection showed high grade dysplasia or cancer. NDBE cases had no visible lesions and an absence of dysplasia in all biopsies. VLE videos were first scored as "neoplastic" or "NDBE." If neoplastic, assessors located the area most suspicious for neoplasia. Primary outcome was the performance of VLE experts in differentiating between non-dysplastic and neoplastic full scan videos, calculated by accuracy, sensitivity, and specificity. Secondary outcomes included correct location of neoplasia, interobserver agreement, and level of confidence.

RESULTS

VLE experts correctly labelled 73 % (95 % confidence interval [CI] 67 % - 79 %) of neoplastic VLE videos. In 54 % (range 27 % - 66 %) both neoplastic diagnosis and lesion location were correct. NDBE videos were consistent with endoscopic biopsies in 52 % (95 %CI 46 % - 57 %). Interobserver agreement was fair (kappa 0.28). High level of confidence was associated with a higher rate of correct neoplastic diagnosis (81 %) and lesion location (73 %).

CONCLUSIONS

Identification of subtle neoplastic lesions in VLE full scans by experts was disappointing. Future studies should focus on improving methodologies for reviewing full scans, development of refined VLE criteria for neoplasia, and computer-aided diagnosis of VLE scans.

Alteration of protein expression and spliceosome pathway activity during Barrett's carcinogenesis

BACKGROUND

Barrett's esophagus (BE) is a known precursor lesion and the strongest risk factor for esophageal adenocarcinoma (EAC), a common and lethal type of cancer. Prediction of risk, the basis for efficient intervention, is commonly solely based on histologic examination. This approach is challenged by problems such as inter-observer variability in the face of the high heterogeneity of dysplastic tissue. Molecular markers might offer an additional way to understand the carcinogenesis and improve the diagnosis-and eventually treatment. In this study, we probed significant proteomic changes during dysplastic progression from BE into EAC.

METHODS

During endoscopic mucosa resection, epithelial and stromal tissue samples were collected by laser capture microdissection from 10 patients with normal BE and 13 patients with high-grade dysplastic/EAC. Samples were analyzed by mass spectrometry-based proteomic analysis. Expressed proteins were determined by label-free quantitation, and gene set enrichment was used to find differentially expressed pathways. The results were validated by immunohistochemistry for two selected key proteins (MSH6 and XPO5).

RESULTS

Comparing dysplastic/EAC to non-dysplastic BE, we found in equal volumes of epithelial tissue an overall up-regulation in terms of protein abundance and diversity, and determined a set of 226 differentially expressed proteins. Significantly higher expressions of MSH6 and XPO5 were validated orthogonally and confirmed by immunohistochemistry.

CONCLUSIONS

Our results demonstrate that disease-related proteomic alterations can be determined by analyzing minute amounts of cell-type-specific collected tissue. Further analysis indicated that alterations of certain pathways associated with carcinogenesis, such as micro-RNA trafficking, DNA damage repair, and spliceosome activity, exist in dysplastic/EAC.

A computer-assisted algorithm for narrow-band imaging-based tissue characterization in Barrett's esophagus

BACKGROUND AND AIMS

The endoscopic evaluation of narrow-band imaging (NBI) zoom imagery in Barrett's esophagus (BE) is associated with suboptimal diagnostic accuracy and poor interobserver agreement. Computer-aided diagnosis (CAD) systems may assist endoscopists in the characterization of Barrett's mucosa. Our aim was to demonstrate the feasibility of a deep-learning CAD system for tissue characterization of NBI zoom imagery in BE.

METHODS

The CAD system was first trained using 494,364 endoscopic images of general endoscopic imagery. Next, 690 neoplastic BE and 557 nondysplastic BE (NDBE) white-light endoscopy overview images were used for refinement training. Subsequently, a third dataset of 112 neoplastic and 71 NDBE NBI zoom images with histologic correlation was used for training and internal validation. Finally, the CAD system was further trained and validated with a fourth, histologically confirmed dataset of 59 neoplastic and 98 NDBE NBI zoom videos. Performance was evaluated using fourfold cross-validation. The primary outcome was the diagnostic performance of the CAD system for classification of neoplasia in NBI zoom videos.

RESULTS

The CAD system demonstrated accuracy, sensitivity, and specificity for detection of BE neoplasia using NBI zoom images of 84%, 88%, and 78%, respectively. In total, 30,021 individual video frames were analyzed by the CAD system. Accuracy, sensitivity, and specificity of the video-based CAD system were 83% (95% confidence interval [CI], 78%-89%), 85% (95% CI, 76%-94%), and 83% (95% CI, 76%-90%), respectively. The mean assessment speed was 38 frames per second.

CONCLUSION

We have demonstrated promising diagnostic accuracy of predicting the presence/absence of Barrett's neoplasia on histologically confirmed unaltered NBI zoom videos with fast corresponding assessment time.

Wide-area transepithelial sampling in adjunct to forceps biopsy increases the absolute detection rates of Barrett's oesophagus and oesophageal dysplasia: a meta-analysis and systematic review

BACKGROUND

Wide-area transepithelial sampling (WATS) is a new technique that uses an abrasive brush to obtain samples from a larger surface area of the oesophagus. Studies have shown promising results that WATS in adjunct to forceps biopsy (FB) increases the detection rate of Barrett's oesophagus (BE) as well as oesophageal dysplasia (ED). We conducted a systematic review and meta-analysis to compare the detection rates of BE and ED between FB and WATS in adjunct to FB.

METHODS

A Literature search was done using electronic databases, including PubMed, Embase, Scopus, Cochrane and CINAHL from inception to 26 April 2020. A meta-analysis comparing detection rates of WATS in adjunct to FB versus FB using the random-effects model was done using RevMan V.5.3.

RESULTS

Pooled data from 20 392 endoscopies across 11 studies showed an absolute increase in detection of 16% (95% CI 0.10% to 0.22%, p<0.00001). A relative increase of 1.62 was seen in detection rates of BE (95% CI 1.28 to 2.05, p<0.0001) when WATS was used with FB with the number needed to test (NNT) of 6.1 patients. For ED, a 2% absolute increase (95% CI 0.01 to 0.03, p=0.001) in additional diagnostic yield from WATS. A relative increase of 2.05 was seen in the detection rate of ED (95% CI 1.42 to 2.98, p=0.0001) yielding an NNT of 50 patients.

CONCLUSION

Our study shows that WATS, as an adjunct to FB, improves both the absolute detection rate and relative detection rate of both BE and ED as compared to FB alone.

Multicenter study on the diagnostic performance of multiframe volumetric laser endomicroscopy targets for Barrett's esophagus neoplasia with histopathology correlation

Volumetric laser endomicroscopy (VLE) has been shown to improve detection of early neoplasia in Barrett's esophagus (BE). However, diagnostic performance using histopathology-correlated VLE regions of interest (ROIs) has not been adequately studied. We evaluated the diagnostic accuracy of VLE assessors for identification of early BE neoplasia in histopathology-correlated VLE ROIs. In total, 191 ROIs (120 nondysplastic and 71 neoplastic) from 50 BE patients were evaluated in a random order using a web-based module. All ROIs contained histopathology correlations enabled by VLE laser marking. Assessors were blinded to endoscopic BE images and histology. ROIs were first scored as nondysplastic or neoplastic. Level of confidence was assigned to the predicted diagnosis. Outcome measures were: (i) diagnostic performance of VLE assessors for identification of BE neoplasia in all VLE ROIs, defined as accuracy, sensitivity, and specificity; (ii) diagnostic performance of VLE assessors for only high level of confidence predictions; and (iii) interobserver agreement. Accuracy, sensitivity, and specificity for BE neoplasia identification were 79% (confidence interval [CI], 75-83), 75% (CI, 71-79), and 81% (CI, 76-86), respectively. When neoplasia was identified with a high level of confidence, accuracy, sensitivity, and specificity were 88%, 83%, and 90%, respectively. The overall strength of interobserver agreement was fair (k = 0.29). VLE assessors can identify BE neoplasia with reasonable diagnostic accuracy in histopathology-correlated VLE ROIs, and accuracy is enhanced when BE neoplasia is identified with high level of confidence. Future work should focus on renewed VLE image reviewing criteria and real-time automatic assessment of VLE scans.

Improved Barrett's neoplasia detection using computer-assisted multiframe analysis of volumetric laser endomicroscopy

Volumetric laser endomicroscopy (VLE) is a balloon-based technique, which provides a circumferential near-microscopic scan of the esophageal wall layers, and has potential to improve Barrett's neoplasia detection. Interpretation of VLE imagery in Barrett's esophagus (BE) however is time-consuming and complex, due to a large amount of visual information and numerous subtle gray-shaded VLE images. Computer-aided detection (CAD), analyzing multiple neighboring VLE frames, might improve BE neoplasia detection compared to automated single-frame analyses. This study is to evaluate feasibility of automatic data extraction followed by CAD using a multiframe approach for detection of BE neoplasia. Prospectively collected ex-vivo VLE images from 29 BE-patients with and without early neoplasia were retrospectively analyzed. Sixty histopathology-correlated regions of interest (30 nondysplastic vs. 30 neoplastic) were assessed using different CAD systems. Multiple neighboring VLE frames, corresponding to 1.25 millimeter proximal and distal to each region of interest, were evaluated. In total, 3060 VLE frames were analyzed via the CAD multiframe analysis. Multiframe analysis resulted in a significantly higher median AUC (median level = 0.91) compared to single-frame (median level = 0.83) with a median difference of 0.08 (95% CI, 0.06-0.10), P < 0.001. A maximum AUC of 0.94 was reached when including 22 frames on each side using a multiframe approach. In total, 3060 VLE frames were automatically extracted and analyzed by CAD in 3.9 seconds. Multiframe VLE image analysis shows improved BE neoplasia detection compared to single-frame analysis. CAD with multiframe analysis allows for fast and accurate VLE interpretation, thereby showing feasibility of automatic full scan assessment in a real-time setting during endoscopy.

The Amsterdam ReBus progressor cohort: identification of 165 Barrett's surveillance patients who progressed to early neoplasia and 723 nonprogressor patients

Patient selection is suboptimal in most studies focused on identifying biological markers for neoplastic progression in Barrett's esophagus (BE). This study aims to describe a stringently selected community-based case-control cohort of non-dysplastic BE (NDBE) patients who progressed to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) and BE patients who never progressed to be used for future biomarker studies. We identified all patients referred for endoscopic work-up of BE neoplasia at three tertiary referral centers for treatment of BE neoplasia between 2000 and 2013. We performed a detailed registration of any endoscopic surveillance history before neoplastic progression. Controls were selected from a retrospective BE surveillance registration in 10 community hospitals. A total of 887 patients were referred for endoscopic work-up of BE neoplasia. Based on predefined selection criteria, we identified 165 progressor patients (82% men; mean age 55 years ± 10.4) with a baseline endoscopy demonstrating NDBE > 2 years before neoplastic progression. Using the same predefined selection criteria, 723 nonprogressor patients (67% men; mean age 57 years ± 11.3) with >2 years of endoscopic surveillance were identified. Median length of the BE segment was 5 cm (IQR 4-7) in progressors and 4 cm (IQR 2-6) in controls. Median duration of surveillance was 89 months (IQR 54-139) in progressors and 76 months (IQR 47-116) in nonprogressors. Paraffin embedded biopsies are available for biomarker research in all patients. Ethical approval was obtained and material transfer agreements were signed with all 58 contributing pathology labs. This is the largest community-based case-control cohort of BE patients with and without progression to early neoplasia. The stringent selection criteria and the availability of paraffin embedded biopsy specimens make this a unique cohort for biomarker studies.

Minichromosomal Maintenance Component Complex 5 (MCM5) as a Marker of Barrett's Esophagus-Related Neoplasia: A Feasibility Study

BACKGROUND

The endoscopic detection of esophageal cancer is suboptimal in both patients referred with dyspeptic symptoms and those enrolled in Barrett's surveillance programs. MCM5 expression in cells collected from gastric fluid may be correlated with the presence of dysplasia or adenocarcinoma. Analysis of this biomarker may improve the detection of cancer.

METHODS

Sixty-one patients were enrolled at a single UK referral center. From each patient, 5-10 ml of gastric fluid was aspirated endoscopically. Patients were categorized according to their histology, normal, non-dysplastic Barrett's (NDBE), high-grade dysplastic Barrett's (HGD), and esophageal adenocarcinoma (EAC). All histology was confirmed by Seattle protocol biopsies or endoscopic mucosal resection. Samples were centrifuged, and the cell pellet was lysed. MCM5 expression levels were quantified using a proprietary immunoassay. The mean MCM5 expression was compared between groups by Kruskal-Wallis test. ROC curves were also used to assess diagnostic utility.

RESULTS

The mean expression of MCM5 increases as patients progress from a normal esophagus to NDBE, HGD, and EAC (14.4; 49.8; 112.3; and 154.1, respectively). There was a significant difference in the MCM5 expression of patients with a normal esophagus compared to those with EAC (p = 0.04). There was a trend toward higher MCM5 expression in patients with EAC compared to those with NDBE (p = 0.34). MCM5 expression was a fair discriminator (AUC 0.70 [95% CI 0.57-0.83]) between patients without neoplasia (normal and NDBE) and those with early neoplasia (HGD and EAC).

CONCLUSION

MCM5 expression in gastric fluid samples can differentiate patients with a histologically normal esophagus compared to those with early adenocarcinoma. Larger, powered studies are needed to assess whether it can be used to differentiate those with HGD from NDBE.

Advances in the diagnosis and surveillance of Barrett's esophagus (with videos)

BACKGROUND AND AIMS

Most patients diagnosed with esophageal adenocarcinoma do not carry a known diagnosis of Barrett's esophagus (BE), suggesting that an improved approach to screening may potentially be of benefit. The use of dysplasia as a biomarker and random biopsy protocols for its detection has limitations. In addition, detecting and appropriately classifying dysplasia in patients with known BE can be difficult.

METHODS

This document reviews several technologies with a recently established or potential role in the diagnosis and/or surveillance of BE as well as risk stratification for progression to esophageal adenocarcinoma.

RESULTS

Two technologies were reviewed for imaging or tissue sampling: (1) wide-area transepithelial sampling and (2) volumetric laser endomicroscopy. Four technologies were reviewed for molecular and biomarker technologies for diagnosis and risk stratification: (1) Cytosponge, (2) mutational load, (3) fluorescence in situ hybridization, and (4) immunohistochemistry.

CONCLUSION

Several technologies discussed in this document may improve dysplasia detection in BE in a wide-field manner. Moreover, the addition of different biomarkers may aid in enhanced risk stratification to optimize approaches to surveillance or treatment for patients with BE.

Virtual chromoendoscopy by using optical enhancement improves the detection of Barrett's esophagus-associated neoplasia

BACKGROUND AND AIMS

The Seattle protocol for endoscopic Barrett's esophagus (BE) surveillance samples a small portion of the mucosal surface area, risking a potentially high miss rate of early neoplastic lesions. We assessed whether the new iScan Optical Enhancement system (OE) improves the detection of early BE-associated neoplasia compared with high-definition white-light endoscopy (HD-WLE) in both expert and trainee endoscopists to target sampling of suspicious areas. Such a system may both improve early neoplasia detection and reduce the need for random biopsies.

METHODS

A total of 41 patients undergoing endoscopic BE surveillance from January 2016 to November 2017 were recruited from 3 international referral centers. Matched still images in both HD-WLE (n = 130) and iScan OE (n = 132) were obtained from endoscopic examinations. Two experts, unblinded to the videos and histology, delineated known neoplasia, forming a consensus criterion standard. Seven expert and 7 trainee endoscopists marked 1 position per image where they would expect a target biopsy to identify dysplastic tissue. The same expert panel then reviewed magnification images and, using a previously validated classification system, attempted to classify mucosa as dysplastic or nondysplastic, based on the mucosal and vascular (MV) patterns observed on magnification endoscopy. Diagnostic accuracy, sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were calculated. Improvements in dysplasia detection in HD-WLE versus OE and interobserver agreement were assessed by multilevel logistic regression analysis and Krippendorff alpha, respectively. Improvements in diagnostic performance were expressed as an odds ratio between the odds of improvement in OE compared with the odds of improvement in HD-WLE.

RESULTS

Accuracy of neoplasia detection was significantly higher in all trainees who used OE versus HD-WLE (76% vs 63%) and in 6 experts (84% vs 77%). OE improved sensitivity of dysplasia detection compared with HD-WLE in 6 trainees (81% vs 71%) and 5 experts (77% vs 67%). Specificity improved in 6 trainees who used OE versus HD-WLE (70% vs 55%) and in 5 experts (92% vs 86%). PPV improved in both an expert and trainee cohort, but NPV improved significantly only in trainees. By using the MV classification and OE magnification endoscopy compared with HD-WLE, we demonstrated improvements in accuracy (79.9% vs 66.7%), sensitivity (86.3% vs 83.4%), and specificity (71.2% vs 53.6%) of dysplasia detection. PPV improved (62%-76.6%), as did NPV (67.7%-78.5%). Interobserver agreement also improved by using OE from 0.30 to 0.55.

CONCLUSION

iScan OE may improve dysplasia detection on endoscopic imaging of BE as well as the accuracy of histology prediction compared with HD-WLE, when OE magnification endoscopy is used in conjunction with a simple classification system by both expert and non-expert endoscopists.

A biomarker panel predicts progression of Barrett's esophagus to esophageal adenocarcinoma

Progression from Barrett's esophagus (BE) to esophageal adenocarcinoma (EAC) is uncommon but the consequences are serious. Predictors of progression are essential to optimize resource utilization. This study assessed the utility of a promising panel of biomarkers applicable to routine paraffin embedded biopsies (FFPE) to predict progression of BE to EAC in a large population-based, nested case-control study.We utilized the Amsterdam-based ReBus nested case-control cohort. BE patients who progressed to high-grade dysplasia (HGD)/EAC (n = 130) and BE patients who never progressed (n = 130) were matched on age, sex, length of the BE segment, and duration of endoscopic surveillance. All progressors had minimum 2 years of endoscopic surveillance without HGD/EAC to exclude prevalent neoplasia. We assessed abnormal DNA content, p53, Cyclin A, and Aspergillus oryzae lectin (AOL) in FFPE sections. We performed conditional logistic regression analysis to estimate odds ratio (OR) of progression based on biomarker status.Expert LGD (OR, 8.3; 95% CI, 1.7-41.0), AOL (3 vs. 0 epithelial compartments abnormal; OR, 3.6; 95% CI, 1.2-10.6) and p53 (OR, 2.3; 95% CI, 1.2-4.6) were independently associated with neoplastic progression. Cyclin A did not predict progression and DNA ploidy analysis by image cytometry was unsuccessful in the majority of cases, both were excluded from the multivariate analysis. The multivariable biomarker model had an area under the receiver operating characteristic curve of 0.73.Expert LGD, AOL, and p53 independently predict neoplastic progression in BE patients and are applicable to routine practice. These biomarkers can aid in selecting patients for endoscopic ablation or more intensive surveillance.

Evolution of Premalignant Disease

Where does cancer come from? Although the cell-of-origin is difficult to pinpoint, cancer clones harbor information about their clonal ancestries. In an effort to find cells before they evolve into a life-threatening cancer, physicians currently diagnose premalignant diseases at frequencies that substantially exceed those of clinical cancers. Cancer risk prediction relies on our ability to distinguish between which premalignant features will lead to cancer mortality and which are characteristic of inconsequential disease. Here, we review the evolution of cancer from premalignant disease, and discuss the concept that even phenotypically normal cell progenies inherently gain more malignant potential with age. We describe the hurdles of prognosticating cancer risk in premalignant disease by making reference to the underlying continuous and multivariate natures of genotypes and phenotypes and the particular challenge inherent in defining a cell lineage as "cancerized."

Emerging endoscopic techniques for the identification of esophageal disease

Esophageal diseases, both benign and malignant, impose an increasing burden to global health. In the West, gastroesophageal reflux disease (GERD) and Barrett's esophagus are increasing in prevalence and impact. In the East, squamous esophageal cancer remains a large burden, but increasingly, precancerous lesions related to GERD are recognized. We review the various advanced endoscopic techniques that have been developed to improve the accuracy of endoscopic identification of esophageal disease. These techniques are designed to increase the sensitivity of detecting disease and high-risk lesions, enable targeted biopsies, decrease total number of biopsies and costs for surveillance, but also guide therapy in real-time. After proper clinical validation, the widespread use of these technologies will lead to improved outcomes, mostly in cancer prevention.

Novel insights into esophageal diagnostic procedures

The 21st century offers new advances in diagnostic procedures and protocols in the management of esophageal diseases. This review highlights the most recent advances in esophageal diagnostic technologies, including clinical applications of novel endoscopic devices, such as ultrathin endoscopy and confocal laser endomicroscopy for diagnosis and management of Barrett's esophagus; novel parameters and protocols in high-resolution esophageal manometry for the identification and better classification of motility abnormalities; innovative connections between esophageal motility disorder diagnosis and detection of gastroesophageal reflux disease (GERD); impedance-pH testing for detecting the various GERD phenotypes; performance of distensibility testing for better pathophysiological knowledge of the esophagus and other gastrointestinal abnormalities; and a modern view of positron emission tomography scanning in metastatic disease detection in the era of accountability as a model for examining other new technologies. We now have better tools than ever for the detection of esophageal diseases and disorders, and emerging data are helping to define how well these tools change management and provide value to clinicians. This review features novel insights from multidisciplinary perspectives, including both surgical and medical perspectives, into these new tools, and it offers guidance on the use of novel technologies in clinical practice and future directions for research.

Volumetric laser endomicroscopy in Barrett's esophagus: a feasibility study on histological correlation

Volumetric laser endomicroscopy (VLE) is a novel balloon-based optical coherence tomography (OCT) imaging technique that may improve detection of early neoplasia in Barrett's esophagus (BE). Most OCT studies lack a direct correlation between histology and OCT images. The aim is to investigate the optimal approach for achieving one-to-one correlation of ex-vivo VLE images of endoscopic resection (ER) specimens with histology. BE patients with and without early neoplasia underwent ER after delineating areas with electrocoagulation markers (ECM). After ER, specimens underwent additional ex-vivo marking with several different markers (ink, pin, Gold Probe) followed by ex-vivo VLE scanning. ER specimens were carefully sectioned into tissue blocks guided by the markers. Histology and VLE slides were considered a match if ≥ 2 markers were visible on both modalities and mucosal patterns aside from these markers matched on both histology and VLE. From 16 ER specimens 120 tissue blocks were sectioned of which 23 contained multiple markers. Fourteen histology-VLE matches were identified. ECMs and ink markers proved to be the most effective combination for matching. The last 6/16 ER specimens yielded 9/14 matches, demonstrating a learning curve due to methodological improvements in marker placement and tissue block sectioning. One-to-one correlation of VLE and histology is complex but feasible. The groundwork laid in this study will provide high-quality histology-VLE correlations that will allow further research on VLE features of early neoplasia in BE.

Diagnosis by Endoscopy and Advanced Imaging of Barrett's Neoplasia

Evaluation of patients with Barrett's esophagus (BE) using dye-based chromoendoscopy, optical chromoendoscopy, autofluorescence imaging, or confocal laser endomicroscopy does not significantly increase the number of patients with a diagnosis of early neoplasia compared with high-definition white light endoscopy (HD-WLE) with random biopsy analysis. These newer imaging techniques are not more effective in standard surveillance of patients with BE because the prevalence of early neoplasia is low and HD-WLE with random biopsy analysis detects most cases of neoplasia. The evaluation and treatment of patients with BE and early stage neoplasia should be centralized in tertiary referral centers, where procedures are performed under optimal conditions, by expert endoscopists. Lesions that require resection are almost always detected by HD-WLE, although advanced imaging techniques can detect additional flat lesions. However, these are of limited clinical significance because they are effectively eradicated by ablation therapy. No endoscopic imaging technique can reliably assess submucosal or lymphangio invasion. Endoscopic resection of early stage neoplasia in patients with BE is important for staging and management. Optical chromoendoscopy can also be used to evaluate lesions before endoscopic resection and in follow-up after successful ablation therapy.

A Multiscale Model Evaluates Screening for Neoplasia in Barrett's Esophagus

Barrett’s esophagus (BE) patients are routinely screened for high grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) through endoscopic screening, during which multiple esophageal tissue samples are removed for histological analysis. We propose a computational method called the multistage clonal expansion for EAC (MSCE-EAC) screening model that is used for screening BE patients in silico to evaluate the effects of biopsy sampling, diagnostic sensitivity, and treatment on disease burden. Our framework seamlessly integrates relevant cell-level processes during EAC development with a spatial screening process to provide a clinically relevant model for detecting dysplastic and malignant clones within the crypt-structured BE tissue. With this computational approach, we retain spatio-temporal information about small, unobserved tissue lesions in BE that may remain undetected during biopsy-based screening but could be detected with high-resolution imaging. This allows evaluation of the efficacy and sensitivity of current screening protocols to detect neoplasia (dysplasia and early preclinical EAC) in the esophageal lining. We demonstrate the clinical utility of this model by predicting three important clinical outcomes: (1) the probability that small cancers are missed during biopsy-based screening, (2) the potential gains in neoplasia detection probabilities if screening occurred via high-resolution tomographic imaging, and (3) the efficacy of ablative treatments that result in the curative depletion of metaplastic and neoplastic cell populations in BE in terms of the long-term impact on reducing EAC incidence.

Endoscopic screening for detecting cancer and cancer precursors in Barrett’s esophagus (BE) is currently informed by repeated systematic biopsying of the metaplastic BE tissue. Here we present a comprehensive multiscale model of the natural history of esophageal adenocarcinoma (EAC), which describes the entire multistage process beginning with the conversion event of normal squamous esophageal tissue to BE metaplasia, the spatio-temporal formation of independent dysplastic and malignant clones at the cell level, and finally the appearance of symptomatic EAC in BE. This model lends itself to a systematic exploration of the efficacy and sensitivity of current biopsy-based screening methods to detect neoplasia in BE patients, as well as alternative screening techniques based on high-resolution imaging of the BE tissue. Moreover, the model can also be used to predict the impact of ablative treatments on the risk of occurrence or recurrence of dysplasia or cancer. Due to the lack of studies that attempt to explicitly model the physical and biological dimensions of the screening process itself, our computational model provides a unique, publicly-available tool to improve understanding of factors that limit the efficacy of current screening protocols for BE patients.

Diagnosis by endoscopy and advanced imaging

Evaluation of patients with Barrett's oesophagus (BO) using dye-based chromoendoscopy, optical chromoendoscopy, autofluorescence imaging, or confocal laser endomicroscopy does not significantly increase the number of patients with a diagnosis of early neoplasia compared with high-definition white light endoscopy (HD-WLE) with random biopsy analysis. These newer imaging techniques are not more effective in standard surveillance of patients with BO because the prevalence of early neoplasia is low and HD-WLE with random biopsy analysis detects most cases of neoplasia. The evaluation and treatment of patients with BO and early-stage neoplasia should be centralized in tertiary referral centers, where procedures are performed under optimal conditions, by expert endoscopists. Lesions that require resection are almost always detected by HD-WLE, although advanced imaging techniques can detect additional flat lesions. However, these are of limited clinical significance because they are effectively eradicated by ablation therapy. No endoscopic imaging technique can reliably assess submucosal or lymphangio-invasion. Endoscopic resection of early-stage neoplasia in patients with BO is important for staging and management. Optical chromoendoscopy can also be used to evaluate lesions before endoscopic resection and in follow-up after successful ablation therapy.

Endoscopic TriModal imaging and biomarkers for neoplasia conjoined: a feasibility study in Barrett's esophagus

In Barrett's esophagus (BE), the normal squamous lining of the esophagus is replaced by specialized columnar epithelium. Endoscopic surveillance with autofluorescence imaging (AFI) and molecular biomarkers have been studied separately to detect early neoplasia (EN) in BE. The combination of advanced-imaging modalities and biomarkers has not been investigated; AFI may help detecting biomarkers as a risk-stratification tool. We retrospectively evaluated a cohort of patients undergoing endoscopy for EN in BE with AFI and correlated five biomarkers (HPP1, RUNX3, p16, cyclin A, and p53) in tissue samples with AFI and dysplasia status. Fifty-eight samples from a previous prospective study were selected: 15 true-positive (TP: AFI-positive, EN), 21 false-positive (FP: AFI-positive, no EN), 12 true-negative (TN1; AFI-negative, no EN in sample), 10 true-negative (TN2: AFI-negative, no EN in esophagus). Methylation-specific RT-PCR was performed for HPP1, RUNX3, p16, and immunohistochemistry for cyclin A, p53. P < 0.05 was considered statistically significant. Bonferroni correction was used for multiple comparisons. P16, cyclin A, p53 correlated with dysplasia (P < 0.01, P = 0.003, P < 0.001, respectively). Increased p16 methylation was observed between TP versus TN2 (P = 0.003) and TN1 versus TN2 (P = 0.04) subgroups, suggesting a field defect. Only p53 correlated with AFI-status (P = 0.003). After exclusion of EN samples, significance was lost. Although correlation with dysplasia status was confirmed for p16, cyclin A and p53, underlining the importance of these biomarkers as an early event in neoplastic progression, none of the investigated biomarkers correlated with AFI status. A larger prospective study is needed to assess the combination of AFI and a larger panel of biomarkers to improve risk stratification in BE.

State of the art in advanced endoscopic imaging for the detection and evaluation of dysplasia and early cancer of the gastrointestinal tract

Ideally, endoscopists should be able to detect, characterize, and confirm the nature of a lesion at the bedside, minimizing uncertainties and targeting biopsies and resections only where necessary. However, under conventional white-light inspection – at present, the sole established technique available to most of humanity – premalignant conditions and early cancers can frequently escape detection. In recent years, a range of innovative techniques have entered the endoscopic arena due to their ability to enhance the contrast of diseased tissue regions beyond what is inherently possible with standard white-light endoscopy equipment. The aim of this review is to provide an overview of the state-of-the-art advanced endoscopic imaging techniques available for clinical use that are impacting the way precancerous and neoplastic lesions of the gastrointestinal tract are currently detected and characterized at endoscopy. The basic instrumentation and the physics behind each method, followed by the most influential clinical experience, are described. High-definition endoscopy, with or without optical magnification, has contributed to higher detection rates compared with white-light endoscopy alone and has now replaced ordinary equipment in daily practice. Contrast-enhancement techniques, whether dye-based or computed, have been combined with white-light endoscopy to further improve its accuracy, but histology is still required to clarify the diagnosis. Optical microscopy techniques such as confocal laser endomicroscopy and endocytoscopy enable in vivo histology during endoscopy; however, although of invaluable assistance for tissue characterization, they have not yet made transition between research and clinical use. It is still unknown which approach or combination of techniques offers the best potential. The optimal method will entail the ability to survey wide areas of tissue in concert with the ability to obtain the degree of detailed information provided by microscopic techniques. In this respect, the challenging combination of autofluorescence imaging and confocal endomicroscopy seems promising, and further research is awaited.

Third-generation autofluorescence endoscopy for the detection of early neoplasia in Barrett's esophagus: a pilot study

In Barrett's esophagus (BE), second-generation autofluorescence imaging (AFI-II) improves targeted detection of high-grade intra-epithelial neoplasia (HGIN) and early cancer (EC), yet suffers from high false-positive (FP) rates. The newest generation AFI (AFI-III) specifically targets fluorescence in malignant cells and may therefore improve detection of early neoplasia and reduce FP rate. The aim was to compare AFI-III with AFI-II for endoscopic detection of early neoplasia in BE. BE patients with endoscopically inconspicuous neoplasia underwent two diagnostic endoscopies (AFI-II/AFI-III) in a single session. End-points: number of patients and lesions with HGIN/EC detected with AFI-II and AFI-III after white-light endoscopy (WLE) and the value of reinspection of AFI-positive areas with WLE and narrow-band imaging. Forty-five patients were included (38 males, age 65 years). Nineteen patients showed HGIN/EC. AFI-II inspection after WLE increased detection of HGIN/EC from 9 to 15 patients (47 to 79%); AFI-III increased detection from 9 to 17 patients (47 to 89%). WLE plus random biopsies diagnosed 13/19 (68%) HGIN/EC patients. One hundred and four abnormal AFI areas were inspected; 23 (22%) showed HGIN/EC. AFI-II increased detection of HGIN/EC from 10 to 18 lesions (43 to 78%). AFI-III increased detection from 10 to 20 lesions (43-87%). FP rate was 86% for AFI-II and AFI-III. Reinspection with WLE or narrow-band imaging reduced FP rate to 21% and 22%, respectively, but misclassified HGIN/EC lesions as unsuspicious in 54% and 31%, respectively. This first feasibility study on third-generation AFI again showed improved targeted detection of HGIN/EC in BE. However, the results do not suggest AFI-III performs significantly better than conventional AFI-II.

The clinical consequences of advanced imaging techniques in Barrett's esophagus

Evaluation of patients with Barrett's esophagus (BE) using dye-based chromoendoscopy, optical chromoendoscopy, autofluorescence imaging, or confocal laser endomicroscopy does not significantly increase the number of patients with a diagnosis of early neoplasia compared with high-definition white light endoscopy (HD-WLE) with random biopsy analysis. These newer imaging techniques are not more effective in standard surveillance of patients with BE because the prevalence of early neoplasia is low and HD-WLE with random biopsy analysis detects most cases of neoplasia. The evaluation and treatment of patients with BE and early-stage neoplasia should be centralized in tertiary referral centers, where procedures are performed under optimal conditions, by expert endoscopists. Lesions that require resection are almost always detected by HD-WLE, although advanced imaging techniques can detect additional flat lesions. However, these are of limited clinical significance because they are effectively eradicated by ablation therapy. No endoscopic imaging technique can reliably assess submucosal or lymphangio-invasion. Endoscopic resection of early-stage neoplasia in patients with BE is important for staging and management. Optical chromoendoscopy can also be used to evaluate lesions before endoscopic resection and in follow-up after successful ablation therapy.

One-step circumferential endoscopic mucosal cap resection of Barrett's esophagus with early neoplasia

BACKGROUND AND OBJECTIVE

Focal endoscopic mucosal resection (EMR) of visible intraepithelial lesions arising within Barrett's esophagus (BE) may miss synchronous lesions that are not endoscopically apparent. Stepwise radical endoscopic resection would obviate this concern by removing all BE; however, it requires repeated endoscopy which may increase the risk of complications, particularly for patients with circumferential BE. The aim of the study was to evaluate the safety and efficacy of one-step complete circumferential resection of BE by cap-assisted EMR (EMR-C) among patients with circumferential BE and high-grade dysplasia or intramucosal carcinoma.

PATIENTS AND METHODS

Between January 2003 and March 2010, 47 patients with circumferential BE and biopsy-proven high-grade dysplasia or intramucosal cancer underwent EMR-C. We evaluated: (1) complete eradication of neoplasia, (2) complete eradication of metaplasia, and (3) complications including bleeding and esophageal stricture.

RESULTS

Complete eradication of neoplasia and complete eradication of metaplasia were achieved after a median follow-up of 18.4 months in 91% (43/47) of patients. After EMR-C, two patients (one IMC, one invasive cancer) underwent esophagectomy. Histology of the resected specimens showed no residual disease and a T1bN0 lesion, respectively. Two patients had progression of neoplasia. A stenosis occurred in 18 out of 45 patients (40%). All stenoses were treated with dilations and two required temporary placement of a covered stent.

CONCLUSION

One-step complete EMR-C is a safe and effective technique which can be considered in patients with early neoplastic lesions. Although 40% of patients developed dysphagia, this could well be managed endoscopically.

Acetic acid-enhanced chromoendoscopy is more cost-effective than protocol-guided biopsies in a high-risk Barrett's population

To examine the efficacy and potential cost implications of acetic acid (AA) chromoendoscopy in the assessment of Barrett's neoplasia. Our prospective database of patients referred between 2005 and 2010 with suspected early neoplasia was reviewed. High-resolution Fujinon gastroscopes and EPX-4400 processor were used. Inspection of Barrett's neoplasia was carried out using white light followed by AA. Neoplastic areas were noted, and targeted biopsy was carried out. This was followed by quadrantic biopsies of the remaining Barrett's neoplasia. The cost of protocol-guided biopsies was compared with AA-guided biopsy protocols. Two hundred sixty-three procedures on 197 patients were examined. High-risk neoplasia was found during 143 procedures. In 96% of cases it was identified with AA. The cost of histological evaluation by Cleveland protocol would be £139,416.30. The cost by AA-targeted biopsy followed by random biopsies in one pot would be £25,032.50. For AA-targeted biopsies alone the cost would be £9,541.8 but results in a 4% miss rate. AA localizes neoplastic lesions in the majority of patients and could potentially represent a significant cost saving in patients with suspected neoplasia.

Endoscopic therapies for Barrett's-associated dysplasia: a new paradigm for a new decade

The emergence of endoscopic therapies for Barrett's esophagus (BE)-associated dysplasia has significantly altered the management of this complex disease. Over the past decade, there has been a paradigm shift from that of pure surveillance to a more therapeutic approach in eradicating dysplastic BE. This strategy includes less invasive options than esophagectomy for high-grade dysplasia and early eradication of confirmed low-grade dysplasia. Although multiple modalities exist for endoscopic therapy, endoscopic mucosal resection coupled with radiofrequency ablation appears to be the most effective therapy, with minimal complications. Recent advances in endoscopic eradication therapies for dysplastic BE have fueled excitement for a significant weapon against the rising incidence of esophageal cancer.

Current state of endoscopic therapies in Barrett's esophagus and esophageal cancer

Barrett's esophagus (BE) is a premalignant condition that predisposes patients to esophageal adenocarcinoma. This risk increases with increasing dysplasia, especially in patients with BE and high-grade dysplasia. Radical esophagectomy had long been the only option for these patients; however, it has been associated with significant morbidity and mortality. Endoscopic therapies have been increasingly used as an alternative to radical esophagectomy given the minimally invasive nature and tolerability of the procedure relative to surgery. Currently, the most widely used endoscopic therapies include endoscopic mucosal resection, photodynamic therapy, CryoSpray ablation, and radiofrequency ablation. Retrospective and prospective studies on the use of each of these modalities in patients with nondysplastic BE, dysplastic BE, and early esophageal cancer have demonstrated their effectiveness in eradication of dysplasia with or without reversion of Barrett's epithelium to normal squamous epithelium of the esophagus. These modalities are well tolerated, safe, and have few side effects. Ultimately, more research is needed regarding their ability to fully displace surgical intervention as the gold standard, although at this point their role in poor operative candidates or patients seeking conservative approaches remains promising.

Endoscopic tri-modal imaging is more effective than standard endoscopy in identifying early-stage neoplasia in Barrett's esophagus

BACKGROUND & AIMS

Endoscopic tri-modal imaging (ETMI) incorporates high-resolution endoscopy (HRE), autofluorescence imaging (AFI), and narrow band imaging (NBI). A recent uncontrolled study found that ETMI improved the detection of high-grade dysplasia (HGD) and early carcinoma (Ca) in Barrett's esophagus (BE). The aim was to compare ETMI with standard video endoscopy (SVE) for the detection of HGD/Ca with the use of a randomized cross-over design.

METHODS

Patients referred for work-up of inconspicuous HGD/Ca were eligible and underwent both SVE and ETMI in randomized order within an interval of 6-12 weeks. During ETMI, inspection with HRE was followed by AFI. Detected lesions were inspected in detail with NBI and biopsied, followed by random biopsies. During SVE, any visible lesion was biopsied followed by random biopsies.

RESULTS

Eighty-seven patients with BE underwent ETMI and SVE. No significant difference was observed in overall histologic yield between ETMI and SVE. ETMI had a significantly higher targeted yield compared with SVE because of AFI. However, the yield of targeted biopsies of ETMI was significantly inferior to the overall yield of SVE. Detailed inspection with NBI reduced the false-positive rate of HRE + AFI from 71% to 48% but misclassified 17% of HGD/Ca lesions as not suspicious.

CONCLUSIONS

ETMI statistically significant improves the targeted detection of HGD/Ca compared with SVE. Subsequent characterization of lesions with NBI appears to be of limited value. At this stage, ETMI cannot replace random biopsies for detection of lesions or targeted biopsies for characterization of lesions in a high-risk population.

Zooming in on Barrett oesophagus using narrow-band imaging: an international observer agreement study

BACKGROUND

Several classifications of mucosal morphology have been proposed in Barrett oesophagus using narrow-band imaging (NBI). We evaluated a simplified classification in which only the regularity of mucosal and vascular patterns were evaluated.

AIM

To assess the inter and intraobserver agreement and the correlation with histology of a simplified NBI classification of mucosal morphology in Barrett oesophagus combining the experience of two referral centres.

METHODS

Two hundred NBI images [57 high-grade intraepithelial neoplasia (HGIN)/early cancer (EC)] were evaluated twice by four NBI-experienced and four nonexperienced endoscopists in the field of NBI. Endoscopists assessed each image for: quality, suspicion for dysplasia, and regularity of mucosal and vascular patterns. Observer agreement was assessed using kappa statistics.

RESULTS

Overall interobserver agreement for the items evaluated was 'moderate' and varied between 0.42 and 0.44. Overall intraobserver agreement was 'moderate' to 'substantial' (kappa 0.60-0.62). There were no significant differences in agreement between expert and nonexpert endoscopists. Endoscopist correctly identified 71% of the images containing HGIN/EC. Of the areas without HGIN/EC, 68% were correctly identified as not suspicious. Again, there were no significant differences between experts and nonexperts.

CONCLUSION

Our proposed, simplified classification for Barrett mucosal morphology has a moderate interobserver and a moderate to substantial intraobserver agreement. The lack of differences in agreements between expert and nonexpert endoscopists suggests a short learning curve. The disappointing rate for correctly indentifying HGIN/EC, questions, however, whether detailed inspection of Barrett oesophagus with NBI can replace histological sampling.

The Seattle protocol does not more reliably predict the detection of cancer at the time of esophagectomy than a less intensive surveillance protocol

BACKGROUND & AIMS

The optimal management of high-grade dysplasia in Barrett's esophagus remains controversial. A biopsy protocol consisting of 4 quadrant jumbo biopsies (every 1 cm) with biopsies of mucosal abnormalities (the Seattle protocol) is considered to be the optimal method for detecting early cancers in patients with high-grade dysplasia, although it has never been validated. This study aimed to determine the frequency of unsuspected carcinoma at esophagectomy in Barrett's esophagus patients with high-grade dysplasia who underwent the Seattle protocol and to compare the findings with those of a less rigorous biopsy protocol.

METHODS

Thirty-three patients with high-grade dysplasia underwent esophagectomy. None had obvious mass lesions at preoperative endoscopy. Patients were divided into group 1 (preoperative surveillance biopsies according to Seattle protocol) and group 2 (4 quadrant biopsies every 2 cm). Preoperative and postoperative diagnoses were confirmed by 2 expert gastrointestinal pathologists.

RESULTS

Unsuspected intramucosal cancer was found in 8 of 20 (40%) patients in group 1 versus 4 of 13 (30%) in group 2 (P = .6). Preoperative mucosal nodularity was observed in 4 of 8 (50%) postoperative intramucosal cancers from group 1 versus 3 of 4 (75%) from group 2. Multifocal high-grade dysplasia was seen preoperatively in 7 of 8 (87.5%) postoperative intramucosal cancers in group 1 versus 2 of 4 (50%) in group 2. No patient had submucosal cancer or lymph node metastases at surgery.

CONCLUSIONS

Intense preoperative biopsy sampling by the Seattle protocol does not more reliably predict the detection of cancer at the time of esophagectomy than a less intensive surveillance protocol. This calls into question the concept that extensive sampling with the Seattle protocol consistently detects early cancers arising in Barrett's esophagus patients with high-grade dysplasia.

Low prevalence of submucosal invasive carcinoma at esophagectomy for high-grade dysplasia or intramucosal adenocarcinoma in Barrett's esophagus: a 20-year experience

BACKGROUND

The rate of occult adenocarcinoma at esophagectomy in patients with Barrett's esophagus (BE) and high-grade dysplasia (HGD) has been reported to be approximately 40%. Recently, it has been suggested that this risk may be overestimated.

OBJECTIVE

Our purpose was to determine the rate of submucosal invasive adenocarcinoma in patients undergoing esophagectomy for BE after biopsy diagnosis of HGD or intramucosal carcinoma (IMC). A secondary aim was to identify clinical risk factors for submucosal invasive adenocarcinoma in these patients.

DESIGN

A retrospective study.

SETTING

Tertiary referral center.

PATIENTS

All patients with preoperative BE with HGD or IMC treated with esophagectomy over a 20 year period.

INTERVENTIONS

Esophagectomy.

MAIN OUTCOME MEASUREMENTS

Submucosal invasive adenocarcinoma at esophagectomy.

RESULTS

Sixty patients were included (41 with preoperative HGD, 19 with preoperative IMC). The overall rate of submucosal invasive carcinoma was 6.7% (95% CI, 1.8%-16.2%) (n = 4), with a 5% rate of submucosal invasion in patients with preoperative HGD and 11% for patients with preoperative IMC. All 4 patients with submucosal invasion at esophagectomy had either nodular or ulcerated mucosa on preoperative endoscopy. The 1-year and 5-year all-cause risks of death for the entire cohort were 1.9% and 10.9%, respectively.

LIMITATIONS

Retrospective study.

CONCLUSIONS

The rate of submucosal invasive adenocarcinoma at esophagectomy in BE patients with HGD or IMC on biopsy is much lower than 40%. After adequate sampling and staging, patients with BE with HGD and IMC, especially those without endoscopically visible lesions, can potentially be treated by nonsurgical (local) therapies.

Endoscopic OCT with forward-looking probe: clinical studies in urology and gastroenterology

In the current paper we present results of application of endoscopic time-domain OCT (EOCT) with lateral scanning by forward looking miniprobe. We analysed material of clinical studies of 554 patients: 164 patients with urinary bladder pathology, and 390 with gastrointestinal tract pathology. We reviewed the materials obtained in different clinics using the OCT device elaborated at the Institute of Applied Physics. We demonstrate results of EOCT application in detection of early cancer and surgery guidance, examples of combined use of OCT and fluorescence imaging. As a result, we show the diagnostic accuracy of EOCT in specific clinical tasks. The sensitivity of EOCT cancer determination in Barrett's esophagus is from 71% to 85% at different stages of neoplasia with specificity 68% for all stages. As for bladder carcinoma, the sensitivity and specificity are 85% and 68%, respectively. In colon dysplasia EOST demonstrates high efficacy: sensitivity 92% and specificity 84%.

Barrett's Esophagus: Diagnosis, Screening, Surveillance, and Controversies

Barrett's esophagus (BE) is a frequent complication of gastroesophageal reflux disease, an acquired condition resulting from persistent mucosal injury to the esophagus. The incidence of Barrett's metaplasia and Barrett's adenocarcinoma has been increasing, but the prognosis of Barrett's adenocarcinoma is worse because individuals present at a late stage. Attempts have been made to intervene at early stage using surveillance programmes, although proof of efficacy of endoscopic surveillance is lacking. There is much to be learned about BE. Whether adequate control of gastroesophageal reflux early in the disease alters the natural history of Barrett's change once it has developed remains unanswered. Thus there is great need for carefully designed large randomised controlled trials to address these issues in order to determine how best to manage patients with BE. The AspECT and BOSS clinical trials proride this basis.

Extent of low-grade dysplasia is a risk factor for the development of esophageal adenocarcinoma in Barrett's esophagus

OBJECTIVES

Previous studies that evaluated extent of high-grade dysplasia (HGD) as a risk factor for esophageal adenocarcinoma (EA) in Barrett's esophagus (BE) were conflicting, and no prior study has evaluated extent of low-grade dysplasia (LGD) as a risk factor. The aim of this discovery study was to evaluate the hypothesis that extent of LGD and HGD are risk factors for progression to EA.

METHODS

We evaluated baseline biopsies from 77 BE patients with dysplasia including 44 who progressed to EA and 33 who did not progress during follow-up. The total numbers of LGD and HGD crypts were determined separately by counting all crypts and the extent of LGD, HGD, and total dysplasia were correlated with EA outcome.

RESULTS

Thirty-one and 46 patients had a maximum diagnosis of LGD and HGD, respectively. When the crypts were stratified by dysplasia grade, the mean number of LGD crypts per patient was borderline higher in progressors (93.9) compared with nonprogressors (41.2, P= 0.07), and the mean proportion of LGD crypts per patient was significantly higher in progressors (46.4%vs 26.0%, P= 0.037). Neither the mean number of HGD crypts per patient (P= 0.14) nor the mean proportion of HGD crypts per patient (P= 0.20) was significantly associated with EA outcome.

CONCLUSIONS

The extent of LGD is a significant risk factor for the development of EA in BE in this study. Although the presence of HGD is significantly associated with a greater relative risk for development of EA, the extent of HGD was not an independent risk factor for progression.

Office-based unsedated small-caliber endoscopy is equivalent to conventional sedated endoscopy in screening and surveillance for Barrett's esophagus: a randomized and blinded comparison

OBJECTIVES

A major limitation to screening and surveillance of Barrett's esophagus is the complexity, expense, and risk associated with sedation for upper endoscopy. This study examines the feasibility, accuracy, and patient acceptability of office-based unsedated endoscopy as an alternative.

METHODS

Of 274 eligible adults scheduled for endoscopic screening for gastroesophageal reflux symptoms or surveillance of Barrett's esophagus at a tertiary care center, 121 underwent unsedated small-caliber endoscopy and conventional endoscopy in a randomized crossover study. The two procedures were compared with regard to histological detection of Barrett's esophagus and dysplasia and biopsy size. Patients answered questionnaires assessing the tolerability of the procedures.

RESULTS

The prevalence of Barrett's esophagus was 26% using conventional endoscopy and 30% using unsedated endoscopy (P= 0.503). The level of agreement between the two approaches was "moderate" (kappa= 0.591). Each modality detected four cases of low-grade dysplasia with concordance on one case. The tissue samples collected with unsedated endoscopy were smaller than with conventional endoscopy (P < 0.001). The majority of subjects rated their experience with both procedures as being well tolerated with minimal or no difficulty. When asked which procedure they would prefer in the future, 71% (81/114) chose unsedated small-caliber endoscopy.

CONCLUSIONS

Office-based unsedated small-caliber endoscopy is technically feasible, well tolerated, and accurate in screening for Barrett's esophagus, despite yielding a smaller biopsy specimen. This approach bears the potential to eliminate the infrastructure and cost required for intravenous sedation in this application.

Barrett's esophagus and adenocarcinoma of the gastroesophageal junction: a pathologic perspective

Barrett's esophagus is defined clinically by the presence of endoscopically evident columnar mucosa in the distal esophagus with histopathologic confirmation of the presence of intestinal-type epithelium. The etiology of Barrett's esophagus is understood poorly, but chronic gastroesophageal reflux disease is considered a major contributing factor. Barrett's esophagus is associated with the development of adenocarcinoma of the gastroesophageal junction. It is believed that the development of a Barrett-type mucosa with intestinal goblet-type cells is due to an altered process of differentiation of pluripotent epithelial stem cells in response to the local injury and repair process. The potential identification and isolation of markers for screening purposes and possibly prognostic information are areas of considerable clinical and scientific interest.

Acetic acid-enhanced magnification endoscopy in the diagnosis of specialized intestinal metaplasia, dysplasia and early cancer in Barrett's oesophagus

BACKGROUND

Barrett's surveillance is prone to sampling error. Aim To determine whether enhanced magnification endoscopy using acetic acid instillation improves diagnostic accuracy of specialized intestinal metaplasia/dysplasia in Barrett's oesophagus.

METHODS

We examined the detection rate of the specialized intestinal metaplasia/dysplasia in 64 consecutive patients with Barrett's oesophagus using acetic acid to enhance mucosal pit patterns. Histology was compared with the previous findings at recent conventional surveillance in 62 patients. We also examined the inter-/intra-observer agreement in the assessment of the enhanced magnification endoscopy pit pattern findings.

RESULTS

Histology revealed columnar-lined oesophagus in six (9%) patients, specialized intestinal metaplasia in 49 (77%), low-grade dysplasia in five (8%), high-grade dysplasia in one (2%), and adenocarcinoma in three (5%). There was discordance between the histologic findings from conventional surveillance with random biopsy. Fifteen patients (24%) had a histological upgrade with enhanced magnification endoscopy. There was a high detection rate of specialized intestinal metaplasia even in short segment Barrett's oesophagus (74%), and additionally, there were two cancers, one with 2-cm Barrett's oesophagus and one ultra-short (1 cm). The mean kappa values for inter- and intra-observer agreement in assessing the pit patterns were 0.571 (0.041) and 0.709 (0.038), respectively.

CONCLUSIONS

Enhanced magnification endoscopy allows clear visualization of the epithelial pit patterns within Barrett's oesophagus, and targeted biopsy results in a high yield of specialized intestinal metaplasia and dysplasia.

Barrett's esophagus specialist clinic: what difference can it make?

A 'Barrett's specialist clinic' was set up in our institution consisting of a specialist nurse, research fellow, and a consultant gastroenterologist. The aim of our study was to examine the impact of this clinic in the management of patients with Barrett's esophagus (BE). Patients with the diagnosis of BE seen in the outpatient departments or in the endoscopy unit were referred to this clinic. Guidelines were introduced modelling the American College of Gastroenterology recommendation. Patients were assessed based on their comorbidity and willingness to undergo surveillance. Reflux symptom control and acid suppression was addressed. All patients were invited to undergo high-resolution enhanced magnification endoscopy (EME) and targeted biopsy to confirm the diagnosis and to form a management plan. During the appointment in the clinic, patients were given an option to fill a questionnaire that inquired about the information given to them regarding BE. One hundred and forty-three patients (92 men, mean age: 62 years) with a diagnosis of BE were seen in the specialist clinic. In 16 patients surveillance was stopped. In 25 patients treatment was changed due to poor control of reflux symptoms. Sixty-five patients (51%) answered the questionnaire. Seventy-five patients (58%) underwent high resolution EME. Twelve patients, had a histological upgrade after EME, in spite of a short mean screening interval (5.5 months). The 'Barrett's specialist clinic' introduced a more structured approach in our institution and changed the way these patients were managed. Our results indicate the need for local guidelines and Barrett's specialist clinics in the UK, and perhaps in the rest of the Western world, wherein the burden of this condition is increasing.