Editorial: Best Practices in Surveillance of Barrett's Esophagus

Barrett's Esophagus: An Updated Review

Barrett’s esophagus (BE) is a change in the distal esophageal mucosal lining, whereby metaplastic columnar epithelium replaces squamous epithelium of the esophagus. This change represents a pre-malignant mucosal transformation which has a known association with the development of esophageal adenocarcinoma. Gastroesophageal reflux disease is a risk factor for BE, other risk factors include patients who are Caucasian, age > 50 years, central obesity, tobacco use, history of peptic stricture and erosive gastritis. Screening for BE remains selective based on risk factors, a screening program in the general population is not routinely recommended. Diagnosis of BE is established with a combination of endoscopic recognition, targeted biopsies, and histologic confirmation of columnar metaplasia. We aim to provide a comprehensive review of the epidemiology, pathogenesis, screening and advanced techniques of detecting and eradicating Barrett’s esophagus.

Artificial intelligence and early esophageal cancer

The development of esophageal cancer (EC) from early to advanced stage results in a high mortality rate and poor prognosis. Advanced EC not only poses a serious threat to the life and health of patients but also places a heavy economic burden on their families and society. Endoscopy is of great value for the diagnosis of EC, especially in the screening of Barrett’s esophagus and early EC. However, at present, endoscopy has a low diagnostic rate for early tumors. In recent years, artificial intelligence (AI) has made remarkable progress in the diagnosis of digestive system tumors, providing a new model for clinicians to diagnose and treat these tumors. In this review, we aim to provide a comprehensive overview of how AI can help doctors diagnose early EC and precancerous lesions and make clinical decisions based on the predicted results. We analyze and summarize the recent research on AI and early EC. We find that based on deep learning (DL) and convolutional neural network methods, the current computer-aided diagnosis system has gradually developed from in vitro image analysis to real-time detection and diagnosis. Based on powerful computing and DL capabilities, the diagnostic accuracy of AI is close to or better than that of endoscopy specialists. We also analyze the shortcomings in the current AI research and corresponding improvement strategies. We believe that the application of AI-assisted endoscopy in the diagnosis of early EC and precancerous lesions will become possible after the further advancement of AI-related research.

Barrett's esophagus: current standards in advanced imaging

Esophageal adenocarcinoma (EAC) continues to be one of the fastest rising incident cancers in the Western population with the majority of patients presenting with late stage disease and associated with a dismal 5-year survival rate. Barrett's esophagus (BE) is the only identifiable precursor lesion to EAC. Strategies to screen for and survey BE are critical to detect earlier cancers and reduce morbidity and mortality related to EAC. A high-quality endoscopic examination with careful inspection of the Barrett's segment and adherence to the Seattle protocol for tissue sampling are critical. Advanced imaging modalities offer the potential to improve dysplasia detection, predict histopathology in real time and guide endoscopic eradication therapy (EET). Several technologies have been studied and although most are not yet recommended for routine clinical practice, high definition white light endoscopy (HD-WLE) as well as chromoendoscopy (including virtual chromoendoscopy) improved dysplasia detection in numerous studies supporting their use. Future studies should evaluate the role of artificial intelligence in optimizing detection of dysplasia in BE patients.

Endoscopic Eradication Therapy for Barrett's Neoplasia: Where Do We Stand a Decade Later?

PURPOSE OF REVIEW

Barrett's esophagus (BE) is the only known precursor to esophageal adenocarcinoma (EAC), a cancer associated with increasing incidence and poor survival. Early identification and effective treatment of BE-related neoplasia prior to the development of invasive adenocarcinoma are essential to limiting the morbidity and mortality associated with this cancer. In this review, we summarized the recent evidence guiding endoscopic eradication therapies (EET) for neoplastic BE.

RECENT FINDINGS

New sampling technologies and the application of artificial intelligence (AI) systems have potential to revolutionize early neoplasia detection in BE. EET for BE are safe and effective in achieving complete eradication of intestinal metaplasia (CE-IM) and reducing the progression to EAC, a practice endorsed by all GI society guidelines. EET should be considered in patients with high-grade dysplasia (HGD), intramucosal carcinoma (IMC), and select cases with low-grade dysplasia (LGD). The increasing use of endoscopic submucosal dissection (ESD) in the West may allow EET of select cases with submucosal EAC. Post-EET surveillance strategies will continue to evolve as knowledge of specific risk factors and long-term neoplasia recurrence rates improve. In the last decade, major advancements in EET for neoplastic BE have been achieved. These now represent the standard of care in the management of BE-related dysplasia and intramucosal cancer.

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.

Endoscopic eradication therapy for Barrett's oesophagus: state of the art

PURPOSE OF REVIEW

Barrett's oesophagus is the only identifiable precursor lesion to oesophageal adenocarcinoma. The stepwise progression of Barrett's oesophagus to dysplasia and invasive carcinoma provides the opportunity to intervene and reduce the morbidity and mortality associated with this lethal cancer. Several studies have demonstrated the efficacy and safety of endoscopic eradication therapy (EET) for the management of Barrett's oesophagus related neoplasia. The primary goal of EET is to achieve complete eradication of intestinal metaplasia (CE-IM) followed by enrolment of patients in surveillance protocols to detect recurrence of Barrett's oesophagus and Barrett's oesophagus related neoplasia.

RECENT FINDINGS

EET depends on early and accurate detection and diagnosis of Barrett's oesophagus related neoplasia. All visible lesions should be resected followed by ablation of the remaining Barrett's epithelium. After treatment, patients should be enrolled in endoscopic surveillance programmes. For nondysplastic Barrett's oesophagus, surveillance alone is recommended. For low-grade dysplasia, both surveillance and ablation are reasonable options and should be decided on an individual basis according to patient risk factors and preferences. EET is preferred for high-grade dysplasia and intramucosal carcinoma. For T1b oesophageal adenocarcinoma, esophagectomy remains the standard of care, but endoscopic therapy can be considered in select cases.

SUMMARY

EET is now standard of care and endorsed by societal guidelines for the treatment of Barrett's oesophagus related neoplasia. Future studies should focus on risk stratification models using a combination of clinical data and biomarkers to identify ideal candidates for EET, and to predict recurrence. Optimal therapy for T1b cancer and surveillance strategy after CE-IM are topics that require further study.

Endoscopists systematically undersample patients with long-segment Barrett's esophagus: an analysis of biopsy sampling practices from a quality improvement registry

BACKGROUND AND AIMS

Guidelines recommend systematic biopsy sampling in Barrett's esophagus (BE) to reduce sampling error. Adherence to this biopsy sampling protocol has been suggested as a quality indicator; however, estimates of adherence are not available. Using a national registry, we assessed adherence and identified predictors of adherence to biopsy sampling protocols.

METHODS

We analyzed data from the GI Quality Improvement Consortium Registry that included procedure indication, demographics, endoscopy, and pathology results. Patients with an indication of BE screening/surveillance or an endoscopic finding of BE were included. Adherence to the Seattle protocol was assessed by dividing BE length by number of pathology jars, with a ratio ≤2.0 with rounding down (lenient definition) or rounding up (stringent definition) for odd BE lengths considered adherent. Variables associated with adherence were assessed using generalized estimating equations to control for clustering within individual physicians.

RESULTS

Of 786,712 EGDs assessed, 58,709 (7.5%) EGDs in 53,541 patients met inclusion criteria (mean age, 61.3 years; 60.4% men; 90.2% white; mean BE length, 2.3 cm). When the lenient and stringent definitions for adherence were used, 87.8% and 82.7% of EGDs were adherent, respectively. Increasing BE length was the most significant predictor of nonadherence (odds ratio, .69; 95% confidence interval, .67-.71). Other predictors were increasing age, male gender, increasing American Society of Anesthesiologists class, and practice location. Performance of EGD by nongastroenterologist physicians was associated with nonadherence (odds ratio, .07; 95% confidence interval, .06-.10).

CONCLUSIONS

Nearly 20% of endoscopies performed in BE patients were not adherent to the Seattle protocol. As BE length increases, endoscopists become less compliant with odds of nonadherence increasing by 31% with every 1-cm increase in length.

Over-Utilization of Repeat Upper Endoscopy in Patients with Non-dysplastic Barrett's Esophagus: A Quality Registry Study

INTRODUCTION

Guidelines recommend that patients with non-dysplastic Barrett's esophagus (NDBE) undergo surveillance endoscopy every 3-5 years. Using a national registry, we assessed compliance to recommended surveillance intervals in patients with NDBE and identified factors associated with compliance.

METHODS

We analyzed data from the GI Quality Improvement Consortium registry. Data abstracted include procedure indication, demographics, endoscopy/pathology results, and recommendations for future endoscopy. Patients with an indication of Barrett's esophagus (BE) screening or surveillance, or an endoscopic finding of BE, with non-dysplastic intestinal metaplasia on pathological examination, were included. Compliance was defined as a recommendation to undergo subsequent endoscopy between 3 and 5 years. Multivariate logistic regression was conducted to assess variables associated with compliance.

RESULTS

Of 786,712 endoscopies assessed, 58,709 (7.5%) endoscopies in 53,541 patients met inclusion criteria (mean age 61.3 years, 60.4% men, 90.2% white, mean BE length was 2.3 cm). Most cases were performed by Gastroenterologists (92.3%) with propofol (78.7%). A total of 29,978 procedures (55.8%) resulted in pathology-confirmed BE. Among procedures with NDBE (n = 25,945), 29.9% were noncompliant with the 3-year threshold; most (26.9%) recommended surveillance at 1- to 2-year intervals. Patient factors such as extremes of age, black race, geographic region, type of sedation, and increasing BE length were associated with noncompliance.

DISCUSSION

Approximately 30% of patients with NDBE are recommended to undergo surveillance endoscopy too soon. Patient factors associated with inappropriate utilization include extremes of age, black race, and increasing BE length. Compliance with appropriate endoscopic follow-up as a quality measure in BE is poor.

Biomarker identification and trans-regulatory network analyses in esophageal adenocarcinoma and Barrett's esophagus

BACKGROUND

Esophageal adenocarcinoma (EAC) is an aggressive disease with high mortality and an overall 5-year survival rate of less than 20%. Barrett's esophagus (BE) is the only known precursor of EAC, and patients with BE have a persistent and excessive risk of EAC over time. Individuals with BE are up to 30-125 times more likely to develop EAC than the general population. Thus, early detection of EAC and BE could significantly improve the 5-year survival rate of EAC. Due to the limitations of endoscopic surveillance and the lack of clinical risk stratification strategies, molecular biomarkers should be considered and thoroughly investigated.

AIM

To explore the transcriptome changes in the progression from normal esophagus (NE) to BE and EAC.

METHODS

Two datasets from the Gene Expression Omnibus (GEO) in NCBI Database (https://www.ncbi.nlm.nih.gov/geo/) were retrieved and used as a training and a test dataset separately, since NE, BE, and EAC samples were included and the sample sizes were adequate. This study identified differentially expressed genes (DEGs) using the R/Bioconductor project and constructed trans-regulatory networks based on the Transcriptional Regulatory Element Database and Cytoscape software. Enrichment of Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) terms was identified using the Database for Annotation, Visualization, and Integrated Discovery (DAVID) Bioinformatics Resources. The diagnostic potential of certain DEGs was assessed in both datasets.

RESULTS

In the GSE1420 dataset, the number of up-regulated DEGs was larger than that of down-regulated DEGs when comparing EAC vs NE and BE vs NE. Among these DEGs, five differentially expressed transcription factors (DETFs) displayed the same trend in expression across all the comparison groups. Of these five DETFs, E2F3, FOXA2, and HOXB7 were up-regulated, while PAX9 and TFAP2C were down-regulated. Additionally, the majority of the DEGs in trans-regulatory networks were up-regulated. The intersection of these potential DEGs displayed the same direction of changes in expression when comparing the DEGs in the GSE26886 dataset to the DEGs in trans-regulatory networks above. The receiver operating characteristic curve analysis was performed for both datasets and found that TIMP1 and COL1A1 could discriminate EAC from NE tissue, while REG1A, MMP1, and CA2 could distinguish BE from NE tissue. DAVID annotation indicated that COL1A1 and MMP1 could be potent biomarkers for EAC and BE, respectively, since they participate in the majority of the enriched KEGG and GO terms that are important for inflammation and cancer.

CONCLUSION

After the construction and analyses of the trans-regulatory networks in EAC and BE, the results indicate that COL1A1 and MMP1 could be potential biomarkers for EAC and BE, respectively.

A Survey of Expert Practice and Attitudes Regarding Advanced Imaging Modalities in Surveillance of Barrett's Esophagus

BACKGROUND

Published guidelines do not address what the minimum incremental diagnostic yield (IDY) for detection of dysplasia/cancer is required over the standard Seattle protocol for an advanced imaging modality (AIM) to be implemented in routine surveillance of Barrett's esophagus (BE) patients. We aimed to report expert practice patterns and attitudes, specifically addressing the minimum IDY in the use of AIMs in BE surveillance.

METHODS

An international group of BE experts completed an anonymous electronic survey of domains relevant to surveillance practice patterns and use of AIMs. The evaluated AIMs were conventional chromoendoscopy (CC), virtual chromoendoscopy (VC), volumetric laser endomicroscopy (VLE), confocal laser endomicroscopy (CLE), and wide-area transepithelial sampling (WATS3D). Responses were recorded using five-point balanced Likert items and analyzed as continuous variables.

RESULTS

The survey response rate was 84% (61/73)-41 US and 20 non-US. Experts were most comfortable with and routinely use VC and CC, and least comfortable with and rarely use VLE, CLE, and WATS3D. Experts rated data from randomized controlled trials (1.4 ± 0.9) and guidelines (2.6 ± 1.2) as the two most influential factors for implementing AIMs in clinical practice. The minimum IDY of AIMs over standard biopsies to be considered of clinical benefit was lowest for VC (15%, IQR 10-29%) and highest for VLE (30%, IQR 20-50%). Compared to US experts, non-US experts reported higher use of CC for BE surveillance (p < 0.001).

CONCLUSION

These results should inform benchmarks that need to be met for guidelines to recommend the routine use of AIMs in the surveillance of BE patients.

Controversies in Endoscopic Eradication Therapy for Barrett's Esophagus

Advances in endoscopic eradication therapy for Barrett's Esophagus-associated neoplasia have resulted in a significant paradigm shift in the diagnosis and management of this complex disease. A robust body of literature critically evaluating outcomes of resection and ablative strategies has allowed gastroenterologists to make quality, evidence-based decisions for their patients. Despite this progress, there are still many unanswered questions and challenges that remain. Ultimately, identification of a cost-effective screening modality, biomarkers for risk stratification, and strides to eliminate post surveillance endoscopy after endoscopic eradication therapy are essential to reach our long-term goal for eradication of esophageal adenocarcinoma.