Diagnosis and management of Barrett's esophagus for the endoscopist

Understanding the Columnar Lined Esophagus and Its Variations in Length With Age: A Cadaveric Study

Introduction Columnar lined epithelium (CLE) of the esophagus holds particular importance in diagnosing Barrett's esophagus (BE). In Asia, the prevalence of BE ranges from 0.06% to 6.2%. In India, prevalence estimates vary from 2.6% to 23%. The frequency of esophageal adenocarcinoma has also been observed to be increasing alarmingly over the past few decades. The length of CLE as a criterion for diagnosing BE is the subject of considerable debate. Changes in CLE length among different age groups may exist. Our study aims to measure the length of CLE, or the distance between the angle of His and the Z Line (AZ distance), in normal individuals from Northeast India, and to analyze its variation across different age groups. Materials and methods The study was conducted in the Department of Anatomy and the Department of Forensic Medicine and Toxicology at Gauhati Medical College, Guwahati, Assam, India, during the period 2017-2019. Once opened, each specimen was laid flat on a board. The distance between the A and Z lines was measured using a pair of vernier calipers. This distance was recorded as the AZ distance in millimeters (mm). Results The mean AZ Distance was found to be 12.4 ± 5.3 mm. A significant correlation between age and AZ distance was observed. Conclusion Our present study suggests that the length of the CLE increases with age. This observation offers an opportunity to revisit or revise the diagnostic criteria based on CLE length, taking into account the age of the individual.

Guide mapping for effective superficial photothermal coagulation of the esophagus using computer simulations with ex vivo sheep model validation study

OBJECTIVES

The transfer and widespread acceptance of laser-induced thermal therapy into gastroenterology remain a topic of interest. However, a practical approach to the quantitative effect of photothermal injury in the esophagus needs further investigation. Here, we aim to perform computer simulations that simulate laser scanning and calculate the laser-induced thermal damage area. The simulation engine offers the results in a guide map for laser coagulation with a well-confined therapeutic area according to laser irradiance and surface scanning speed. The study also presents validation experiments that include histology analyses in an ex vivo sheep esophagus model.

METHODS

The simulation engine was developed based on the Monte-Carlo method and the Arrhenius damage integral. The computational model mimicked laser scanning by shifting the position of the calculated heat source in the grating system along the axis to be scanned. The performance of the simulations was tested in an ex vivo sheep esophagus model at a laser wavelength of 1505 nm. Histological analysis, hematoxylin-eosin staining, light microscope imaging, and block-face scanning electron microscopy were used to assess thermal damage to the tissue model.

RESULTS

The developed simulation engine estimated the photothermal coagulation area for a surface scanning speed range of 0.5-8 mm/second and laser power of up to 0.5 W at a 0.9-nm laser diameter in a tissue model with a volume of 4 × 4 × 4 mm³ . For example, the optimum laser irradiation for effective photothermal coagulation in the mucosa and superficial submucosa depths was estimated to be between 16.4 and 31.8 W/cm² , 23.2 and 38.1 W/cm² at 0.5 and 1 mm/second, respectively. The computational results, summarized as a guide map, were directly compared with the results of ex vivo tissue experiments. In addition, it was pointed out that the comparative theoretical and experimental data overlap significantly in terms of energy density.

CONCLUSIONS

Our results suggest that the developed simulation approach could be a seed algorithm for further preclinical and clinical trials and a complementary tool to the laser-induced photothermal coagulation technique for superficial treatments in the gastrointestinal tract. In future preclinical studies, it is thought that the simulation engine can be enriched by combining it with an in vivo model for different laser wavelengths.

Genome-wide tracts of homozygosity and exome analyses reveal repetitive elements with Barrets esophagus/esophageal adenocarcinoma risk

BACKGROUND

Barrett's esophagus (BE) is most commonly seen as the condition in which the normal squamous epithelium lining of the esophagus is replaced by goblet cells. Many studies show that BE is a predisposing factor for the development of esophageal adenocarcinoma (EAC), a particularly lethal cancer. The use of single nucleotide polymorphisms (SNPs) to map BE/EAC genes has previously provided insufficient genetic information to fully characterize the heterogeneous nature of the disease. We therefore hypothesize that rigorous interrogation of other types of genomic changes, e.g. tracts of homozygosity (TOH), repetitive elements, and insertion/deletions, may provide a comprehensive understanding of the development of BE/EAC.

RESULTS

First, we used a case-control framework to identify TOHs by using SNPs and tested for association with BE/EAC. Second, we used a case only approach on a validation series of eight samples subjected to exome sequencing to identify repeat elements and insertion/deletions. Third, insertion/deletions and repeat elements identified in the exomes were then mapped onto genes in the significant TOH regions. Overall, 24 TOH regions were significantly differentially represented among cases, as compared to controls (adjusted-P = 0.002-0.039). Interestingly, four BE/EAC-associated genes within the TOH regions consistently showed insertions and deletions that overlapped across eight exomes. Predictive functional analysis identified NOTCH, WNT, and G-protein inflammation pathways that affect BE and EAC.

CONCLUSIONS

The integration of common TOHs (cTOHs) with repetitive elements, insertions, and deletions within exomes can help functionally prioritize factors contributing to low to moderate penetrance predisposition to BE/EAC.

EXPRESSION OF MUC2 GLYCOPROTEIN ANTIBODY AND VASCULAR ENDOTHELIAL GROWTH FACTOR IN BARRETT'S MUCOSA

Higher expression of the mucin 2 (MUC2) glycoprotein and vascular endothelial growth factor (VEGF) in Barrett's mucosa may be associated with a higher risk of esophageal adenocarcinoma development. Thirty-six patients diagnosed with Barrett's esophagus (BE), short-segment, were included in the study due to unsuccessful treatment with proton pump inhibitors. The diagnosis was confirmed by histopathologic analysis of the tissue obtained by esophagogastric junction biopsy. Expression of MUC2 and VEGF was determined by immunohistochemistry. We found four patients in early stage of adenocarcinoma and 32 patients with BE; five of them had indication for argon plasma coagulation treatment, one for radiofrequency ablation and one for endoscopic mucosal resection; 25 patients were treated with proton pump inhibitors. Regression of BE occurred in 25 (69.44%) patients. MUC2 positivity is unique for goblet cells in patients with BE, but it is not the only marker. VEGF is an indicator of angiogenesis in the mucosa of patients with BE and adenocarcinoma.

Mucosal Ablation Techniques for Barrett's Esophagus and Early Esophageal Cancer

Patients with esophageal intestinal metaplasia, or Barrett's esophagus, may undergo dysplastic changes that eventually lead to invasive adenocarcinoma. Endoscopic therapy in the form of radiofrequency ablation and cryoablation has been described as a minimally invasive intervention to halt this sequence of dysplasia to carcinoma. Studies demonstrate that the use of radiofrequency ablation and cryoablation is highly successful at eradicating intestinal metaplasia and dysplasia and reducing the risk of disease progression. Furthermore, these modalities also may be used in combination with endoscopic mucosal resection, or as stand-alone therapy, for the treatment of intramucosal carcinoma, potentially circumventing the need for surgery.

Weight Loss and Resolution of Comorbidities After Sleeve Gastrectomy: A Review of Long-Term Results

BACKGROUND AND AIMS:

Laparoscopic sleeve gastrectomy (SG) has massively increased in numbers over the last decade and is the most frequently performed bariatric procedure worldwide today. The aim of this review is to evaluate SG in terms of weight loss and resolution of comorbidities, based on data gained from the latest long-term studies available.

MATERIAL AND METHODS:

This review includes the results of any long-term studies on SG available at this point as well as a selection of short- and mid-term studies.

RESULTS:

There are only a handful of studies on sleeve gastrectomy with long-term follow-up available at this point. Conversion rates in these long-term studies amount to up to one-third of their cohorts; however, excess weight loss in patients maintaining their sleeve is over 50%. Results on the resolution of comorbidities vary among the studies available today.

SUMMARY:

Sleeve gastrectomy is a valid bariatric method but one has to be aware of its limitations.

Incidence, Survival, and Predictors of Lymph Node Involvement in Early-Stage Gastric Signet Ring Cell Carcinoma in the US

INTRODUCTION

The incidence, survival, and propensity for nodal metastasis in early-stage gastric signet ring cell carcinoma have not been defined in the United States. These data are critical determinants for treatment allocation.

METHODS

Cases of gastric signet ring cell carcinoma were extracted from the national SEER database for the years 2004-2013. Age-standardized incidence was derived. Survival was calculated using the Kaplan-Meier method. Univariate and multivariate analyses were performed to identify predictors of nodal metastasis. Exclusion criteria included neoadjuvant radiotherapy and lack of histologic or nodal data.

RESULTS

A total of 10,624 cases were initially identified. The analysis cohort included 506 cases with early T-stage N0M0 disease following exclusions. The incidence was 0.094 per 100,000 person-years. The 5-year survival rate was 82.8%. Tumor stage (p < 0.001) and size (p < 0.001) were independent predictors of nodal metastasis. The incidence of nodal involvement for T1a tumors <2 cm was 5.4% (p < 0.004).

CONCLUSION

The incidence of potentially resectable signet ring gastric carcinoma has not changed significantly over the past decade. While presenting with predominantly high-grade histology, early T-stage disease has a high survival rate. Small T1a tumors have low rates of nodal metastasis, suggesting that an endoscopic resection could be considered in this subset.

Immunohistochemical assessment of Survivin and Bcl3 expression as potential biomarkers for NF-κB activation in the Barrett metaplasia-dysplasia-adenocarcinoma sequence

Non-dysplastic Barrett's oesophagus (NDBE) occurs as a consequence of an inflammatory response triggered through prolonged gastro-oesophageal reflux and it may precede the development of oesophageal adenocarcinoma. NF-κB activation as a result of the inflammatory response has been shown in NDBE, but the possible mechanism involved in the process is unknown. The aim of this study was to assess, using immunohistochemistry, Survivin and Bcl3 expression as potential biomarkers for NF-κB activation along the oesophageal metaplasia-dysplasia-adenocarcinoma sequence. Survivin is an NF-κB-inducible anti-apoptotic protein, and Bcl3 is a negative regulator of NF-κB. There was progressive upregulation of Survivin expression along the oesophageal metaplasia-dysplasia-adenocarcinoma sequence. Bcl3 expression was upregulated in non-dysplastic Barrett's oesophagus, low-grade, high-grade dysplasia and oesophageal adenocarcinoma when compared to squamous group. The study shows the differential expression of Bcl3 between the squamous and Barrett's stage, suggesting that Bcl3 could be a surrogate marker for early event involving constitutive NF-κB activation. In addition, the study suggests that NF-κB activation may infer resistance to apoptosis through the expression of anti-apoptotic genes such as Survivin, which showed progressive increase in expression throughout the oesophageal metaplasia-dysplasia-adenocarcinoma sequence. This ability to avoid apoptosis may underlie the persistence and malignant predisposition of Barrett's metaplasia.

Diagnosis and Endoscopic Management of Barrett's Esophagus: an Italian Experts' Opinion based document

BACKGROUND

Barrett's esophagus (BE) is recognized as a risk factor for esophageal adenocarcinoma. An expert panel was organized in Italy with the aim of drafting a series of statements on BE to guide diagnosis and management of patients with BE.

METHODS

The working Group Coordinators worked on a literature search to identify key topics regarding critical steps of the endoscopic approach to BE. Based on the search and their expert opinion, a list of most meaningful questions was prepared and emailed to all members who were asked to vote the questions. When the survey was completed a consensus meeting was organized. According to the survey results, Group Coordinators proposed a draft statement that was voted. By definition, the statement was formulated when there was an agreement of ≥50% among participants.

RESULTS

Twenty nine participants deliberated 18 questions. The agreement was reached for 16 questions for which a recommendation was formulated.

CONCLUSION

The generated statements highlight the Italian contribution to the European Position Statement of the European Society of Gastrointestinal Endoscopy. The Italian statements preserve peculiarities when dealing with the endoscopic management of BE and wishes to be considered as a contribution for the care of BE patients even with a low risk of progression to esophageal neoplasia.

Barrett Esophagus and Intramucosal Esophageal Adenocarcinoma

Barrett esophagus (BE) is a precursor lesion for esophageal adenocarcinoma (EAC). Developments in imaging and molecular markers, and endoscopic eradication therapy, are available to curb the increase of EAC. Endoscopic surveillance is recommended, despite lack of data. The cancer risk gets progressively downgraded, raising questions about the understanding of risk factors and molecular biology involved. Recent data point to at least 2 carcinogenic pathways operating in EAC. The use of p53 overexpression and high-risk human papillomavirus may represent the best chance to detect progressors. Genome-wide technology may provide molecular signatures to aid diagnosis and risk stratification in BE.

Chemico-mechanical imaging of Barrett's oesophagus

Barrett's oesophagus is a condition characterized by a change in the lining of the oesophagus that markedly increases the risk of adenocarcinoma. We demonstrate the first site-matched application of Brillouin microscopy, Raman microscopy and FTIR micro-spectroscopic imaging to ex-vivo epithelial tissue - Barrett's oesophagus. The mechanical and chemical characters of the epithelium were assessed in histological sections from a patient subjected to endoscopic oesophageal biopsy. Previous studies have shown that both these properties change within the oesophageal wall, owing to the presence of distinct cellular and extracellular constituents which are putatively affected by oesophageal cancer. Brillouin microscopy enables maps of elasticity of the epithelium to be obtained, whilst Raman and FTIR imaging provide 'chemical images' without the need for labelling or staining. This site-matched approach provides a valuable platform for investigating the structure, biomechanics and composition of complex heterogeneous systems. A combined Brillouin-Raman device has potential for in-vivo diagnosis of pathology. First application of site-matched micro Brillouin, Raman and FTIR spectroscopic imaging to epithelial tissue in Barrett's oesophagus.

Advances in upper gastrointestinal endoscopy

The rapidly moving technological advances in gastrointestinal endoscopy have enhanced an endoscopist's ability to diagnose and treat lesions within the gastrointestinal tract. The improvement in image quality created by the advent of high-definition and magnification endoscopy, alongside image enhancement, produces images of superb quality and detail that empower the endoscopist to identify important lesions that have previously been undetectable. Additionally, we are now seeing technologies emerge, such as optical coherence tomography and confocal laser endomicroscopy, that allow the endoscopist to visualize individual cells on a microscopic level and provide a real time, in vivo histological assessment. Within this article we discuss these technologies, as well as some of the results from their early use in clinical studies.

Negative surveillance endoscopy occurs frequently in patients with short-segment non-dysplastic Barrett's esophagus

Surveillance endoscopy of non-dysplastic Barrett's esophagus (NDBE) that fails to detect intestinal metaplasia (IM), or negative surveillance, is known to occur in clinical practice, although the frequency and possible outcomes in a large cohort in clinical practice is not well described. The goals of this study were to define frequency in which negative surveillance occurs and endoscopic outcomes in a screening cohort of short segment NDBE. A retrospective cohort (n = 184) of patients newly diagnosed with short segment NDBE at an outpatient academic tertiary care center between 2003 and 2011 were reviewed. Only those with one or more surveillance endoscopies were included to define a frequency of negative surveillance. Included patients were further assessed if they had two or more surveillance endoscopies and were classified into groups as sampling error or negative IM on consecutive surveillances based on the results of their surveillance endoscopies. The frequency of a negative surveillance endoscopy in all short-segment NDBE patients was 19.66% (92 endoscopic exams were negative for IM of 468 total surveillance exams). A negative surveillance endoscopy occurred in 40.76% (n = 75) patients. Sampling error occurred in 44.12% and negative IM on consecutive surveillance endoscopies in 55.88% of those with ≥ 2 surveillance endoscopies and an initially negative surveillance exam. The frequency of negative IM on consecutive surveillances was 19.00% of all patients who had two surveillance endoscopies. When the index diagnostic Barrett's esophagus segment length was < 1 cm, 32.14% (18/56) of all patients (with ≥ 2 surveillance endoscopies) had negative IM on consecutive surveillance endoscopies. Negative surveillance occurs frequently in short-segment NDBE. When an initial negative surveillance endoscopy occurs, it may be due to either a sampling error or lack of detectable IM on surveillance exam. When a <1 cm segment of NDBE is diagnosed, a significant proportion of patients may go on to have continuously undetected IM on consecutive surveillance endoscopic exams without intervention.

Conversion of one cell type into another: implications for understanding organ development, pathogenesis of cancer and generating cells for therapy

Metaplasia is the irreversible conversion of one differentiated cell or tissue type into another. Metaplasia usually occurs in tissues that undergo regeneration, and may, in a pathological context, predispose to an increased risk of disease. Studying the conditions leading to the development of metaplasia is therefore of significant clinical interest. In contrast, transdifferentiation (or cellular reprogramming) is a subset of metaplasia that describes the permanent conversion of one differentiated cell type into another, and generally occurs between cells that arise from neighbouring regions of the same germ layer. Transdifferentiation, although rare, has been shown to occur in Nature. New insights into the signalling pathways involved in normal tissue development may be obtained by investigating the cellular and molecular mechanisms in metaplasia and transdifferentiation, and additional identification of key molecular regulators in transdifferentiation and metaplasia could provide new targets for therapeutic treatment of diseases such as cancer, as well as generating cells for transplantation into patients with degenerative disorders. In the present review, we focus on the transdifferentiation of pancreatic cells into hepatocyte-like cells, the development of Barrett's metaplasia in the oesophagus, and the cellular and molecular mechanisms underlying both processes.

Dysplasia detection rate of confirmatory EGD in nondysplastic Barrett's esophagus

Current guidelines for endoscopic surveillance of Barrett's esophagus (BE) recommend that patients with newly diagnosed BE undergo confirmatory esophagogastroduodenoscopy (EGD) to exclude the presence of dysplasia. The extent to which confirmatory endoscopy alters management and detects missed dysplasia in newly diagnosed BE has not been reported. The frequency with which confirmatory endoscopy changed surveillance management in patients with newly diagnosed BE was assessed. A two center cohort analysis was conducted on patients newly diagnosed with BE. The rate of dysplasia on confirmatory endoscopy for patients who had nondysplastic BE was obtained. Demographic and endoscopic variables were assessed for association with dysplasia detection using Firth logistic regression model. Out of the 146 patients newly diagnosed with BE and initially determined to be without dysplasia, 12 had dysplasia on the confirmatory second EGD (8.2%). Eleven of 12 cases with dysplasia on confirmatory endoscopy had long-segment BE (LSBE). Among all the LSBE cases in our cohort, 11 had newly diagnosed dysplasia on confirmatory EGD, 29.7% (11/37). The average number of biopsies obtained from the 11 LSBE cases with dysplasia was comparable with the rest of the LSBE cases without dysplasia (6.73 and 5.42, respectively, P-value 0.205). The rate of dysplasia detection in short-segment BE (SSBE) was much lower, 0.95% (1 out of 105). There were no cases of high-grade dysplasia (HGD) or cancer detected in any SSBE case. HGD was detected on confirmatory EGD in two cases, both were LSBE. Segment length was the only statistically significant factor to predict the presence of dysplasia on confirmatory endoscopy (odds ratio 9.158, P. 0.008). Confirmatory EGD in newly diagnosed LSBE had significant rate of dysplasia detection (29.7%) in this cohort. Among patients with SSBE, there was a low rate of dysplasia detection with confirmatory EGD, less than 1% of cases. No additional cases of HGD or esophageal carcinoma in SSBE cases were detected. This suggests that the yield of confirmatory EGD is greater in patients with LSBE.

Clinical outcomes of endoscopic submucosal dissection for superficial Barrett's adenocarcinoma

BACKGROUND

Advances in diagnostic techniques have allowed early stage detection of superficial Barrett's adenocarcinoma (SBA) as well as resection by endoscopic submucosal dissection (ESD). Few reports exist, however, on the safety and efficacy of ESD for SBA.

OBJECTIVE

To analyze outcomes of ESD for SBA in relation to clinicopathological features of the lesions.

DESIGN

Retrospective study.

SETTING

University hospital.

PATIENTS

Twenty-three patients (21 men, 2 women; mean age, 63 years) with 26 SBAs.

INTERVENTION ESD MAIN OUTCOME MEASUREMENTS

We examined outcomes of ESD in relation to the clinicopathological features of SBAs. The main outcomes assessed were en bloc resection rate, operation time, adverse event rates, additional resection rate, and time between ESD and any recurrence.

RESULTS

Twenty lesions (87%) derived from short-segment Barrett's esophagus, and 3 lesions (13%) derived from long-segment Barrett's esophagus. The majority of SBAs (54%) were located in the 0 to 3 o'clock circumferential quadrant. Median tumor size was 15 mm (range 5-60 mm). Macroscopic types were flat elevated (n = 13, 50%), depressed (n = 12, 46%), and protruded (n = 1, 4%). The SBAs appeared red (n = 23, 88%) or normally pale (n = 3, 12%). Under magnifying narrow-band imaging, all SBAs showed an irregular mucosal pattern and an irregular vascular pattern. The endoscopic en bloc resection rate was 100% (26/26), and the pathological en bloc resection rate was 85% (22/26). The median procedure time was 95 minutes (range, 30-210 minutes). Delayed bleeding occurred in 1 case, but there was no perforation. The SBAs were of the differentiated type (n = 25, 96%) or poorly differentiated type (n = 1, 4%). The tumor had invaded the superficial muscularis mucosa (n = 3, 12%), lamina propria mucosa (n = 5, 19%, deep muscularis mucosa (n = 9, 34%), SM1 (n = 3, 12%), and SM2 (n = 6, 23%). Additional surgical resection after ESD was performed in 9 cases, and there were no residual tumors, but 1 lymph node metastasis was found. There were no recurrent tumors; however, 1 metachronous adenocarcinoma was diagnosed 42 months after ESD.

LIMITATIONS

Single-center, retrospective study.

CONCLUSIONS

ESD appears to be a safe and effective treatment strategy for early stage SBA.

Barrett's Esophagus

OPINION STATEMENT

Barrett's esophagus (BE) is the most important and recognizable precursor lesion for esophageal adenocarcinoma (EAC), which is the one of the fastest-growing cancers in the Western world (600 % in the U.S. in the last 40 years), and therefore it is critical to manage the risk of cancer present in BE. New developments in imaging and molecular markers, as well as an armamentarium of novel and effective endoscopic eradication therapy - especially radio-frequency ablation (RFA) and endoscopic mucosal resection (EMR) - are now available to the interventional endoscopist to help curb the significant rise of esophageal adenocarcinoma (EAC). Endoscopic surveillance is currently recommended by most gastroenterology societies worldwide, although there is no data to support this practice in relation to reducing mortality from EAC. Paradoxically, the cancer risk in Barrett's esophagus is being progressively downgraded, which raises fundamental questions about our understanding of the risk factors and molecular biology of the Barrett's metaplasia-dysplasia-adenocarcinoma sequence. The recent discovery of a strong association of transcriptionally active high-risk human papillomavirus (hr-HPV) with Barrett's dysplasia (BD) and EAC may shed some light on this anomaly. It is imperative that we identify the high-risk group of progressors to EAC. While p53 immunohistochemistry is currently probably the best clinical molecular marker for predicting disease progression in BD, we must think outside the box and cast the net wide in search of additional biomarkers (e.g., high-risk human papilloma virus (hr-HPV)].

Barrett's esophagus and esophageal cancer: an overview

Although esophageal cancer (EC) is the eighth most common cancer in several European countries, it is one of deadliest worldwide. The most frequent predisposing factor implicated in its development is Barrett's esophagus (BE), an acquired metaplastic transformation of the esophageal lining cells from normal squamous epithelium into specialised or intestinal-like columnar epithelium. The major risk factor for BE is gastroesophageal reflux disease. Although BE is in itself a benign and often asymptomatic disorder, its clinical importance stems from the recognition that it represents the main precursor lesion for the development of esophageal adenocarcinoma (AC), a tumor that is rapidly increasing especially in developed countries and is associated with a low survival rate. This paper provides an overview of the epidemiology and natural history of BE as well as of the possible pathogenetic mechanisms underlying the development of BE and its progressive transition to AC. New diagnostic tests are described, recommendations for screening and surveillance are provided and surgical and ablative procedures to treat dysplastic lesions and early neoplasia are discussed. Claimed chemopreventive agents and biomarkers that in the near future may help identify people with a higher risk of EC are also considered.