Long-term endoscopic surveillance of patients with Barrett's esophagus. Incidence of dysplasia and adenocarcinoma: a prospective study

Post-endoscopy Barrett's neoplasia after a negative index endoscopy: a systematic review and proposal for definitions and performance measures in endoscopy

BACKGROUND

A high rate of neoplasia, both high grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) has been reported in Barrett's esophagus at index endoscopy, but precise rates of post-endoscopy Barrett's neoplasia (PEBN) are unknown.

METHODS

A systematic review and meta-analysis was performed examining electronic databases (inception to October 2021) for studies reporting PEBN. Consistent with the definitions of post-colonoscopy colorectal cancer proposed by the World Endoscopy Organization, we defined neoplasia (HGD/EAC) detected at index endoscopy and/or within 6 months of a negative index endoscopy as "prevalent" neoplasia, that detected after 6 months of a negative index endoscopy and prior to next surveillance interval (i. e. 3 years) as PEBN or "interval" neoplasia, and that detected after 36 months from a negative index endoscopy as "incident" neoplasia. The pooled incidence rates and proportions relative to total neoplasia were analyzed.

RESULTS

11 studies (n = 59 795; 61 % men; mean [SD] age 62.3 [3.3] years) met the inclusion criteria. The pooled incidence rates were: prevalent neoplasia 4.5 % (95 %CI 2.2 %-8.9 %) at baseline and an additional 0.3 % (0.1 %-0.7 %) within the first 6 months, PEBN 0.52 % (0.46 %-0.58 %), and incident neoplasia 1.4 % (0.9 %-2.1 %). At 3 years from the index endoscopy, PEBN accounted for 3 % of total Barrett's neoplasia, while prevalent neoplasia accounted for 97 %.

CONCLUSION

Neoplasia detected at or within 6 months of index endoscopy accounts for most cases of Barrett's neoplasia (> 90 %). PEBN accounts for ~3 % of cases and can be used for validation in future. This highlights the importance of a high quality index endoscopy in Barrett's esophagus and the need to establish quality benchmarks to measure endoscopists' performance.

Endoscopic Diagnosis and Management of Barrett's Esophagus with Low-Grade Dysplasia

Barrett’s Esophagus is a common condition associated with chronic gastroesophageal reflux disease. It is well known that it has an association with a higher incidence of esophageal adenocarcinoma, but this neoplastic transformation is first preceded by the onset of low and high-grade dysplasia. The evaluation of low grade dysplastic esophageal mucosa is still controversial; although endoscopic surveillance is preferred, several minimally invasive endoscopic therapeutic approaches are available. Endoscopic mucosal resection and radiofrequency ablation are the most used endoscopic treatments for the eradication of low-grade dysplasia, respectively, for nodular and flat dysplasia. Novel endoscopic treatments are cryotherapy ablation and argon plasma coagulation, that have good rates of eradication with less complications and post-procedural pain.

Barrett’s esophagus: Review of natural history and comparative efficacy of endoscopic and surgical therapies

Barrett's esophagus (BE) is the precursor to esophageal adenocarcinoma (EAC). Progression to cancer typically occurs in a stepwise fashion through worsening dysplasia and ultimately, invasive neoplasia. Established EAC with deep involvement of the esophageal wall and/or metastatic disease is invariably associated with poor long-term survival rates. This guides the rationale of surveillance of Barrett’s in an attempt to treat lesions at an earlier, and potentially curative stage. The last two decades have seen a paradigm shift in management of Barrett’s with rapid expansion in the role of endoscopic eradication therapy (EET) for management of dysplastic and early neoplastic BE, and there have been substantial changes to international consensus guidelines for management of early BE based on evolving evidence. This review aims to assist the physician in the therapeutic decision-making process with patients by comprehensive review and summary of literature surrounding natural history of Barrett’s by histological stage, and the effectiveness of interventions in attenuating the risk posed by its natural history. Key findings were as follows. Non-dysplastic Barrett’s is associated with extremely low risk of progression, and interventions cannot be justified. The annual risk of cancer progression in low grade dysplasia is between 1%-3%; EET can be offered though evidence for its benefit remains confined to highly select settings. High-grade dysplasia progresses to cancer in 5%-10% per year; EET is similarly effective to and less morbid than surgery and should be routinely performed for this indication. Risk of nodal metastases in intramucosal cancer is 2%-4%, which is comparable to operative mortality rate, so EET is usually preferred. Submucosal cancer is associated with nodal metastases in 14%-41% hence surgery remains standard of care, except for select situations.

Magnitude and Time-Trend Analysis of Postendoscopy Esophageal Adenocarcinoma: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Identification of postendoscopy esophageal adenocarcinoma (PEEC) among Barrett's esophagus (BE) patients presents an opportunity to improve survival of esophageal adenocarcinoma (EAC). We aimed to estimate the proportion of PEEC within the first year after BE diagnosis.

METHODS

Multiple databases (Medline, Embase, Scopus, and Cochrane databases) were searched until September 2020 for original studies with at least 1-year follow-up evaluation that reported EAC and/or high-grade dysplasia (HGD) in the first year after index endoscopy in nondysplastic BE, low-grade dysplasia, or indefinite dysplasia. The proportions of PEEC defined using EAC alone and EAC+HGD were calculated by dividing EAC or EAC+HGD in the first year over the total number of EAC or EAC+HGD, respectively.

RESULTS

We included 52 studies with 145,726 patients and a median follow-up period of 4.8 years. The proportion of PEEC (EAC) was 21% (95% CI, 13-31) and PEEC (EAC+HGD) was 26% (95% CI, 19-34). Among studies with nondysplastic BE only, the PEEC (EAC) proportion was 17% (95% CI, 11-23) and PEEC (EAC+HGD) was 14% (95% CI, 8-19). Among studies with 5 or more years of follow-up evaluation, the PEEC (EAC) proportion was 10% and PEEC (EAC+HGD) was 19%. Meta-regression analysis showed a strong inverse relationship between PEEC and incident EAC (P < .001). The PEEC (EAC) proportion increased from 5% in studies published before 2000 to 30% after 2015. Substantial heterogeneity was observed for most analyses.

CONCLUSIONS

PEEC accounts for a high proportion of HGD/EACs and is proportional to reduction in incident EAC. Using best endoscopic techniques now and performing future research on improving neoplasia detection through implementation of quality measures and educational tools is needed to reduce PEEC.

Long-term endoscopic surveillance for Barrett's esophagus in Japan: Multicenter prospective cohort study

OBJECTS

Although a recent study showed the cancer incidence of Barrett's esophagus (BE) to be 1.2%/year in 251 patient-years in Japan, the long-term outcomes remain unclear. The present study estimated the cancer risk of BE in Japan using our original prospective multicenter cohort.

METHODS

A total of 98 patients with BE of maximum length of ≥2 cm were enrolled during the period of 2010-2012 and received at least one follow-up endoscopy over 5 years thereafter. Cancer incidence rates with 95% confidence interval for occurrence of esophageal adenocarcinoma (EAC) were calculated as the number of events divided by patient-years of follow-up and were expressed as %/year.

RESULTS

Overall, the median endoscopic follow-up period was 59.9 (first and third quartiles, 48.5-60.8) months, constituting a total of 427 patient-years of observation. Since two EAC cases developed, the cancer incidence was 0.47% (0.01%-1.81%)/year. The cancer incidence was 0.39% (-0.16% to 2.44%) in 232 patient-years and 0.31% (-0.13% to 1.95%)/year in 318 patient-years for 55 cases with specialized intestinal metaplasia and 70 with BE ≥3 cm (maximum), respectively. At the end of follow-up, 12 of 92 patients (13.0%) died, but none died from EAC.

CONCLUSION

This is the largest prospective follow-up study with endoscopy to investigate the incidence of EAC in unequivocal BE with the maximum length of ≥2 cm in Japan. Although a further large-scale study will be required to validate our results, the cancer risk of BE in Japan would be lower than previously reported (0.47% vs 1.2%/year).

Inhibition of the BMP pathway prevents development of Barrett's-associated adenocarcinoma in a surgical rat model

INTRODUCTION

Esophageal adenocarcinoma (EAC) is an aggressive cancer, associated with reflux esophagitis and intestinal metaplasia (IM). One underlying biological mechanism, which possibly drives the development of EAC, is the dysregulated expression of Bone Morphogenetic Proteins (BMPs).

AIM

To investigate if local delivery of Noggin, a BMP antagonist, reduced EAC.

METHODS

After obtaining proof of principal on local delivery of a Noggin/Sucralfate substance, a randomized controlled trial to test the effects of Noggin on EAC development was performed in a surgical rat model. In the model, an esophago-jejunostomy leads to development of reflux-esophagitis, IM and eventually EAC. Rats were treated by Noggin/Sucralfate or Sucralfate alone. Treatment was administered from 26 to 29 weeks after the operation.

RESULTS

Of the 112 operated rats, 52 survived beyond 26 weeks. Finally, 25 rats treated with Noggin/Sucralfate and 21 with Sucralfate, were evaluated. At the end, 39 (85%) of the animals had IM while 28 (61%) developed cancer. There were significantly more cancers in the Noggin/Sucralfate arm (50%) versus the Sucralfate group (73%) (Chi square, P < 0.05). Most cancers were mucous producing T3 adenocarcinomas. There were no significant differences in the amount of IM, size or grade of the cancers, or expression of columnar and squamous markers between the two groups.

CONCLUSION

In this study, we demonstrated that inhibition of BMPs by Noggin reduced development of EAC in a surgical esophagitis-IM-EAC rat model. In future, effective targeting of the BMP pathway with selective BMP-inhibitors could become an important asset to improve EAC patient outcome.

Barrett's Epithelium to Esophageal Adenocarcinoma: Is There a "Point of No Return"?

Background: Esophageal adenocarcinoma (EA) arises from Barrett's epithelium (BE), and chronic gastroesophageal reflux disease is considered the strongest risk factor for disease progression. All BE patients undergo acid suppressive therapy, surveillance, and BE removal by surgery or endoscopic ablation, yet the incidence of EAC continues to increase. Despite the known side effects and mortality, the one-size-fits-all approach is the standard clinical management as there are no reliable methods for risk stratification. Methods: Paired-end Illumina NextSeq500 RNA sequencing was performed on total RNA extracted from 20-week intervals (0, 20, 40, and 60 W) of an in vitro BE carcinogenesis (BEC) model to construct time series global gene expression patterns (GEPs). The cells from two strategic time points (20 and 40 W) based on the GEPs were grown for another 20 weeks, with and without further acid and bile salt (ABS) stimulation, and the recurrent neoplastic cell phenotypes were evaluated. Results: Hierarchical clustering of 866 genes with ≥ twofold change in transcript levels across the four time points revealed maximum variation between the BEC20W and BEC40W cells. Enrichment analysis confirmed that the genes altered ≥ twofold during this window period associated with carcinogenesis and malignancy. Intriguingly, the BEC20W cells required further ABS exposure to gain neoplastic changes, but the BEC40W cells progressed to malignant transformation after 20 weeks even in the absence of additional ABS. Discussion: The transcriptomic gene expression patterns in the BEC model demonstrate evidence of a clear threshold in the progression of BE to malignancy. Catastrophic transcriptomic changes during a window period culminate in the commitment of the BE cells to a "point of no return," and removal of ABS is not effective in preventing their malignant transformation. Discerning this "point of no return" during BE surveillance by tracking the GEPs has the potential to evaluate risk of BE progression and enable personalized clinical management.

Ingestible Sensors and Sensing Systems for Minimally Invasive Diagnosis and Monitoring: The Next Frontier in Minimally Invasive Screening

Ingestible electronic systems that are capable of embedded sensing, particularly within the gastrointestinal (GI) tract and its accessory organs, have the potential to screen for diseases that are difficult if not impossible to detect at an early stage using other means. Furthermore, these devices have the potential to (1) reduce labor and facility costs for a variety of procedures, (2) promote research for discovering new biomarker targets for associated pathologies, (3) promote the development of autonomous or semiautonomous diagnostic aids for consumers, and (4) provide a foundation for epithelially targeted therapeutic interventions. These technological advances have the potential to make disease surveillance and treatment far more effective for a variety of conditions, allowing patients to lead longer and more productive lives. This review will examine the conventional techniques, as well as ingestible sensors and sensing systems that are currently under development for use in disease screening and diagnosis for GI disorders. Design considerations, fabrication, and applications will be discussed.

Interaction of epidermal growth factor with COX-2 products and peroxisome proliferator-activated receptor-γ system in experimental rat Barrett's esophagus

Mixed acidic-alkaline refluxate is a major pathogenic factor in chronic esophagitis progressing to Barrett's esophagus (BE). We hypothesized that epidermal growth factor (EGF) can interact with COX-2 and peroxisome proliferator-activated receptor-γ (PPARγ) in rats surgically prepared with esophagogastroduodenal anastomosis (EGDA) with healthy or removed salivary glands to deplete salivary EGF. EGDA rats were treated with 1) vehicle, 2) EGF or PPARγ agonist pioglitazone with or without EGFR kinase inhibitor tyrphostin A46, EGF or PPARγ antagonist GW9662 respectively, 3) ranitidine or pantoprazole, and 4) the selective COX-2 inhibitor celecoxib combined with pioglitazone. At 3 mo, the esophageal damage and the esophageal blood flow (EBF) were determined, the mucosal expression of EGF, EGFR, COX-2, TNFα, and PPARγ mRNA and phospho-EGFR/EGFR protein was analyzed. All EGDA rats developed chronic esophagitis, esophageal ulcerations, and intestinal metaplasia followed by a fall in the EBF, an increase in the plasma of IL-1β, TNFα, and mucosal PGE₂ content, the overexpression of COX-2-, and EGF-EGFR mRNAs, and proteins, and these effects were aggravated by EGF and attenuated by pioglitazone. The rise in EGF and COX-2 mRNA was inhibited by pioglitazone but reversed by pioglitazone cotreated with GW9662. We conclude that 1) EGF can interact with PG/COX-2 and the PPARγ system in the mechanism of chronic esophagitis; 2) the deleterious effect of EGF involves an impairment of EBF and the overexpression of COX-2 and EGFR, and 3) agonists of PPARγ and inhibitors of EGFR may be useful in the treatment of chronic esophagitis progressing to BE.NEW & NOTEWORTHY Rats with EGDA exhibited chronic esophagitis accompanied by a fall in EBF and an increase in mucosal expression of mRNAs for EGF, COX-2, and TNFα, and these effects were exacerbated by exogenous EGF and reduced by removal of a major source of endogenous EGF with salivectomy or concurrent treatment with tyrphostin A46 or pioglitazone combined with EGF. Beneficial effects of salivectomy in an experimental model of BE were counteracted by PPARγ antagonist, whereas selective COX-2 inhibitor celecoxib synergistically with pioglitazone reduced severity of esophageal damage and protected esophageal mucosa from reflux. We propose the cross talk among EGF/EGFR, PG/COX-2, and proinflammatory cytokines with PPARγ pathway in the mechanism of pathogenesis of chronic esophagitis progressing to BE and EAC.

Upper gastrointestinal involvement in systemic sclerosis: Findings in a real-life setting

Gastrointestinal tract involvement is the most common visceral affectation in systemic sclerosis (SSc), but the manifestations may vary in extension and severity. Endoscopic and histopathological gastroesophageal findings were investigated in patients with SSc. A total of 79 consecutive patients with definite SSc were enrolled in a cross sectional study. Clinical data were collected, upper gastrointestinal endoscopy and biopsies from gastric mucosa were performed in all cases. Fifty-seven (72.1%) out of 79 SSc patients had gastroesophageal symptoms. The most frequent were dysphagia, present in 33 (41.7%) and gastroesophageal reflux symptoms in 23 (29.1%) patients. Out of the 79 patients, 22 were asymptomatic, but in 16 esophageal and gastric mucosa changes were endoscopically detected. Reflux esophagitis was found in 39 (49.3%) patients. The presence of esophageal manifestations was not related to the disease duration or with its other variables. Signs of gastritis were endoscopically described in 47 (59.4%) and confirmed on histopathologic examinations in 45 patients. In 31 patients without any endoscopic changes, 18 (22.7%) showed signs of gastritis on histopathologic examination. No significant statistical differences were found between symptomatic and asymptomatic patients or between those with limited cutaneous SSc and those with diffuse cutaneous SSc in terms of clinical, endoscopic or histopathological findings, except the higher proportion of hiatal hernia in symptomatic patients. The results of this study might suggest that upper gastrointestinal endoscopy should be performed during the early stage of the disease and then periodically in patients diagnosed with SSc, even in the absence of typical symptoms.

Inflammatory bowel disease- and Barrett's esophagus-associated neoplasia: the old, the new, and the persistent struggles

Early diagnosis of and adequate therapy for premalignant lesions in patients with inflammatory bowel disease (IBD) and Barrett's esophagus (BE) has been shown to decrease mortality. Endoscopic examination with histologic evaluation of random and targeted biopsies remains the gold standard for early detection and adequate treatment of neoplasia in both these diseases. Although eventual patient management (including surveillance and treatment) depends upon a precise histologic assessment of the initial biopsy, accurately diagnosing and grading IBD- and BE-associated dysplasia is still considered challenging by many general as well as subspecialized pathologists. Additionally, there are continuing updates in the literature regarding the diagnosis, surveillance, and treatment of these disease entities. This comprehensive review discusses the cancer risk, detailed histopathological features, diagnostic challenges, and updates as well as the latest surveillance and treatment recommendations in IBD- and BE-associated dysplasia.

CD80 expression promotes immune surveillance in Barrett's metaplasia

Esophageal adenocarcinoma (EAC) is the final step of a pathway starting with esophageal reflux disease, Barrett’s metaplasia and Barrett’s dysplasia. Positive costimulatory ligands such as CD80 have been suggested to contribute to anti-tumor T-cell efficacy. Here we report for the first time the role of CD80 in the inflammatory esophageal carcinogenesis and characterize the immune environment of EAC. Mucosa samples from cancer were obtained during esophagectomy from patients affected by EAC. Fresh biopsies were obtained from patients who underwent endoscopy for screening or follow-up. A rodent model of reflux induced esophageal carcinogenesis was created with an esophago-gastro-jejunostomy. CD80 expression was increased in epithelial cells during metaplasia in the inflammatory esophageal carcinogenesis cascade. Cd80 null mice as well as WT mice that received antiCD80 antibodies showed a higher rate of dysplasia and KI-67+ cells. These results suggest that CD80 mediates an active immune surveillance process in early inflammation-driven esophageal carcinogenesis.

Microsatellite instability in metaplasia-dysplasia-adenocarcinoma sequence of Barrett esophagus: a retrospective study

Aim

To analyze the loss of mismatch repair (MMR) system protein expression in metaplasia-dysplasia-adenocarcinoma sequence of Barrett esophagus (BE).

Methods

This study retrospectively analyzed the data from 70 patients with pathohistological diagnosis of BE or esophageal adenocarcinoma (EAC) treated at the Clinical Department of Pathology and Cytology, University Hospital Center Zagreb, from January 2009 to January 2011. Patients were divided into three groups: BE without dysplasia (22 patients), BE with dysplasia (37 patients), and EAC (11 patients). Immunohistochemical expression of MutL homologue 1 (MLH1), MutS homologue 2 (MSH2), postmeiotic segregation increased 2 (PMS2), and MutS homologue 6 (MSH6) of DNA MMR system was measured and compared with tumor protein p53 expression.

Results

A total of 81.8% and 81.8% patients with EAC, 32.4% and 35.1% patients with dysplasia, and 50% and 54.5% patients without dysplasia had loss of MLH1 and PMS2 expression, respectively. Patients with EAC and patients with dysplasia did not have loss of MSH2 and MSH6 expression, and 18.2% patients without dysplasia had loss of MSH2 and MSH6 expression. There was a strong positive correlation between MLH1 and PMS2 expression (Spearman ρ 0.97; P < 0.001) and between MSH2 and MSH6 expression (Spearman ρ 0.90, P < 0.001) in the entire sample and in all BE groups. No significant correlations of MLH1 and PMS2 with p53 expression were found, except in dysplasia group (φ 0.402, P = 0.030 for MSH1; φ 0.371, P = 0.042 for PMS2).

Conclusion

Although we demonstrated considerable loss of MLH1 and PMS2 expression in BE-associated carcinoma sequence, due to the retrospective study design and low number of patients we cannot conclude that MLH1 and PMS2 can be used as biomarkers for patient surveillance and therapy-making decisions.

Oxford Centre for Evidence-based Medicine level of evidence: 3

Histological assessment & use of immunohistochemical markers for detection of dysplasia in Barrett's esophageal mucosa

BACKGROUND

Histological assessment of dysplasia in Barrett's esophagus (BE) has high inter-observer variability. Hence, use of ancillary markers for early detection of dysplasia in BE is an important clinical question.

METHODS

In this retrospective study consecutive cases of BE (n = 59), over a period of 4 years were included. Hematoxylin and eosin stained sections were reviewed independently by 3 senior qualified pathologists, who graded the dysplasia according to the Vienna Classification system and inter-observer agreement was analysed using the Kappa statistics. Subsequently Alpha-Methyl Acyl-CoA Racemase (AMACR), p53, CyclinD1, β-catenin, H2AX and M30 immunohistochemical (IHC) stains were examined on the following disease categories: BE with no dysplasia [NFD] (45), BE with indefinite for dysplasia (IFD) (4), low grade dysplasia (LGD) (3), high grade dysplasia (HGD) (2) and in adenocarcinomas (5). H score was calculated by adding up products of different grades of stain distribution and stain intensities (range of scores 0-300).

RESULTS

Among the 3 pathologists, overall agreement was poor (k 0.06; 95% CI -0.089 to 0.145), with highest disagreement noted for differentiating the LGD and IFDs (k = 0.21). After revising the histological criteria, the kappa improved to 0.53. Among the IHC stains performed, p53, β-catenin, H2AX and M30 stains were significantly useful to differentiate between IFD and LGD (P values: 0.04, 0.004, 0.05 & 0.04, respectively). AMACR and β-catenin stains though were up-regulated in HGD/adenocarcinomas than in other categories, their expression were not statistically different between the IFD and LGDs.

CONCLUSIONS

A detail histological scoring system may bring uniformity in histological interpretation of dysplasia in BE. Using a combined panel of IHC stains seems helpful in detection of dysplasia in BE, especially to differentiate the IFD and LGD changes in BE.

Disease Progression in Barrett's Low-Grade Dysplasia With Radiofrequency Ablation Compared With Surveillance: Systematic Review and Meta-Analysis

OBJECTIVES

Barrett's esophagus (BE) is the only identifiable premalignant condition for esophageal adenocarcinoma (EAC). Management of BE with low-grade dysplasia continues to be controversial. We aimed to conduct a systematic review and meta-analysis comparing the risk of progression to high-grade dysplasia or EAC among patients with BE with low-grade dysplasia treated with radiofrequency ablation (RFA) compared with surveillance endoscopy.

METHODS

Our search included Medline, Embase, and Cochrane Central, was limited to English language articles, and was last searched on 31 December 2015. Studies were reviewed by title and abstract, and then full text by two independent reviewers. Two independent reviewers extracted data. Differences were resolved by consensus. The primary outcome of interest was the relative risk of disease progression among patients with BE with low-grade dysplasia treated with RFAcompared with surveillance.

RESULTS

Our search resulted in 2,029 citations, 19 studies were included in the final analysis, totaling 2,746 patients. Relative risk of disease progression in RFA compared with surveillance was 0.14% (95% confidence interval: 0.04-0.45), P=0.001. This measure was stable when only all studies were included. Absolute risk reduction was 10.9% and the number needed to treat was 9.2. Results were stable over several quality measures, overtime, and when excluding randomized trials. The cumulative rate of progression to high-grade dysplasia/EAC was lower in RFA compared with surveillance (1.7% vs. 12.6%, P<0.001).

CONCLUSIONS

Similarly, the incidence rate of progression among patients with surveillance was significantly higher from those treated with RFA (0.022 vs. 0.005, P<0.001). RFA results in a significant reduction risk of disease progression to high-grade dysplasia/EAC among patients with BE with low-grade dysplasia.

Evolutionary dynamics in pre-invasive neoplasia

Mutational processes occur in normal tissues from conception throughout life. Field cancerization describes the preconditioning of an area of epithelium to tumor growth. Pre-invasive lesions may arise in these fields, however only a minority of pre-invasive neoplasia progresses to overt malignancy. Within this review we discuss recent advances in our understanding of genomic instability processes in normal tissue, describe evolutionary dynamics in pre-invasive disease and highlight current evidence describing how increasing genomic instability may drive the transition from pre-invasive to invasive disease. Appreciation of the evolutionary rulebooks that operate in pre-invasive neoplasia may facilitate screening strategies, risk-stratification of pre-invasive lesions and precipitate novel preventative treatments in at-risk patient populations.

Diagnosis and Management of Low-Grade Dysplasia in Barrett's Esophagus: Expert Review From the Clinical Practice Updates Committee of the American Gastroenterological Association

The purpose of this clinical practice update expert review is to define the key principles in the diagnosis and management of low-grade dysplasia (LGD) in Barrett's esophagus patients. The best practices outlined in this review are based on relevant publications, including systematic reviews and expert opinion (when applicable). Practice Advice 1: The extent of Barrett's esophagus should be defined using a standardized grading system documenting the circumferential and maximal extent of the columnar lined esophagus (Prague classification) with a clear description of landmarks and visible lesions (nodularity, ulceration) when present. Practice Advice 2: Given the significant interobserver variability among pathologists, the diagnosis of Barrett's esophagus with LGD should be confirmed by an expert gastrointestinal pathologist (defined as a pathologist with a special interest in Barrett's esophagus-related neoplasia who is recognized as an expert in this field by his/her peers). Practice Advice 3: Expert pathologists should report audits of their diagnosed cases of LGD, such as the frequency of LGD diagnosed among surveillance patients and/or the difference in incidence of neoplastic progression among patients diagnosed with LGD vs nondysplastic Barrett's esophagus. Practice Advice 4: Patients in whom the diagnosis of LGD is downgraded to nondysplastic Barrett's esophagus should be managed as nondysplastic Barrett's esophagus. Practice Advice 5: In Barrett's esophagus patients with confirmed LGD (based on expert gastrointestinal pathology review), repeat upper endoscopy using high-definition/high-resolution white-light endoscopy should be performed under maximal acid suppression (twice daily dosing of proton pump inhibitor therapy) in 8-12 weeks. Practice Advice 6: Under ideal circumstances, surveillance biopsies should not be performed in the presence of active inflammation (erosive esophagitis, Los Angeles grade C and D). Pathologists should be informed if biopsies are obtained in the setting of erosive esophagitis and if pathology findings suggest LGD, or if no biopsies are obtained, surveillance biopsies should be repeated after the anti-reflux regimen has been further intensified. Practice Advice 7: Surveillance biopsies should be performed in a four-quadrant fashion every 1-2 cm with target biopsies obtained from visible lesions taken first. Practice Advice 8: Patients with a confirmed histologic diagnosis of LGD should be referred to an endoscopist with expertise in managing Barrett's esophagus-related neoplasia practicing at centers equipped with high-definition endoscopy and capable of performing endoscopic resection and ablation. Practice Advice 9: Endoscopic resection should be performed in Barrett's esophagus patients with LGD with endoscopically visible abnormalities (no matter how subtle) in order to accurately assess the grade of dysplasia. Practice Advice 10: In patients with confirmed Barrett's esophagus with LGD by expert GI pathology review that persists on a second endoscopy, despite intensification of acid-suppressive therapy, risks and benefits of management options of endoscopic eradication therapy (specifically adverse events associated with endoscopic resection and ablation), and ongoing surveillance should be discussed and documented. Practice Advice 11: Endoscopic eradication therapy should be considered in patients with confirmed and persistent LGD with the goal of achieving complete eradication of intestinal metaplasia. Practice Advice 12: Patients with LGD undergoing surveillance rather than endoscopic eradication therapy should undergo surveillance every 6 months times 2, then annually unless there is reversion to nondysplastic Barrett's esophagus. Biopsies should be obtained in 4-quadrants every 1-2 cm and of any visible lesions. Practice Advice 13: In patients with Barrett's esophagus-related LGD undergoing ablative therapy, radiofrequency ablation should be used. Practice Advice 14: Patients completing endoscopic eradication therapy should be enrolled in an endoscopic surveillance program. Patients who have achieved complete eradication of intestinal metaplasia should undergo surveillance every year for 2 years and then every 3 years thereafter to detect recurrent intestinal metaplasia and dysplasia. Patients who have not achieved complete eradication of intestinal metaplasia should undergo surveillance every 6 months for 1 year after the last endoscopy, then annually for 2 years, then every 3 years thereafter. Practice Advice 15: Following endoscopic eradication therapy, the biopsy protocol of obtaining biopsies in 4 quadrants every 2 cm throughout the length of the original Barrett's esophagus segment and any visible columnar mucosa is suggested. Practice Advice 16: Endoscopists performing endoscopic eradication therapy should report audits of their rates of complete eradication of dysplasia and intestinal metaplasia and adverse events in clinical practice.

Sex and Gender Differences in Gastroesophageal Reflux Disease

It is important to understand sex and gender-related differences in gastroesophageal reflux disease (GERD) because gender-related biologic factors might lead to better prevention and therapy. Non-erosive reflux disease (NERD) affects more women than men. GERD symptoms are more frequent in patients with NERD than in those with reflux esophagitis. However, men suffer pathologic diseases such as reflux esophagitis, Barrett’s esophagus (BE), and esophageal adenocarcinoma (EAC) more frequently than women. The prevalence of reflux esophagitis is significantly increased with age in women, especially after their 50s. The mean age of EAC incidence in women is higher than in men, suggesting a role of estrogen in delaying the onset of BE and EAC. In a chronic rat reflux esophagitis model, nitric oxide was found to be an aggravating factor of esophageal injury in a male-predominant way. In addition, the expression of esophageal occludin, a tight junction protein that plays an important role in the esophageal defense mechanism, was up-regulated in women. This explains the male predominance of reflux esophagitis and delayed incidence of BE or EAC in women. Moreover, the symptoms such as heartburn, regurgitation, and extra-esophageal symptoms have been more frequently reported by women than by men, suggesting that sex and gender play a role in symptom perception. Differential sensitivity with augmented symptoms in women might have diagnostic and therapeutic influence. Furthermore, recent studies have suggested that hormone replacement therapy has a protective effect against esophageal cancer. However, an anti-inflammatory role of estrogen remains compelling, which means further study is necessary in this area.

Current management of the gastrointestinal complications of systemic sclerosis

Systemic sclerosis is a multisystem autoimmune disorder that involves the gastrointestinal tract in more than 90% of patients. This involvement can extend from the mouth to the anus, with the oesophagus and anorectum most frequently affected. Gut complications result in a plethora of presentations that impair oral intake and faecal continence and, consequently, have an adverse effect on patient quality of life, resulting in referral to gastroenterologists. The cornerstones of gastrointestinal symptom management are to optimize symptom relief and monitor for complications, in particular anaemia and malabsorption. Early intervention in patients who develop these complications is critical to minimize disease progression and improve prognosis. In the future, enhanced therapeutic strategies should be developed, based on an ever-improving understanding of the intestinal pathophysiology of systemic sclerosis. This Review describes the most commonly occurring clinical scenarios of gastrointestinal involvement in patients with systemic sclerosis as they present to the gastroenterologist, with recommendations for the suggested assessment protocol and therapy in each situation.

Barrett’s esophagus in 2016: From pathophysiology to treatment

Esophageal complications caused by gastroesophageal reflux disease (GERD) include reflux esophagitis and Barrett’s esophagus (BE). BE is a premalignant condition with an increased risk of developing esophageal adenocarcinoma (EAC). The carcinogenic sequence may progress through several steps, from normal esophageal mucosa through BE to EAC. A recent advent of functional esophageal testing (particularly multichannel intraluminal impedance and pH monitoring) has helped to improve our knowledge about GERD pathophysiology, including its complications. Those findings (when properly confirmed) might help to predict BE neoplastic progression. Over the last few decades, the incidence of EAC has continued to rise in Western populations. However, only a minority of BE patients develop EAC, opening the debate regarding the cost-effectiveness of current screening/surveillance strategies. Thus, major efforts in clinical and research practice are focused on new methods for optimal risk assessment that can stratify BE patients at low or high risk of developing EAC, which should improve the cost effectiveness of screening/surveillance programs and consequently significantly affect health-care costs. Furthermore, the area of BE therapeutic management is rapidly evolving. Endoscopic eradication therapies have been shown to be effective, and new therapeutic options for BE and EAC have emerged. The aim of the present review article is to highlight the status of screening/surveillance programs and the current progress of BE therapy. Moreover, we discuss the recent introduction of novel esophageal pathophysiological exams that have improved the knowledge of the mechanisms linking GERD to BE.

Impact of surveillance for Barrett's oesophagus on tumour stage and survival of patients with neoplastic progression

OBJECTIVE

Endoscopic surveillance for Barrett's oesophagus (BO) is under discussion given the overall low incidence of neoplastic progression and lack of evidence that it prevents advanced oesophageal adenocarcinoma (OAC). The aim of this study was to evaluate the impact of endoscopic BO surveillance on tumour stage and survival of patients with neoplastic progression.

DESIGN

783 patients with BO of at least 2 cm were included in a multicentre prospective cohort and followed during surveillance according to the American College of Gastroenterology guidelines. Cases of high-grade dysplasia and OAC were identified during follow-up. OAC staging was performed according to the 7th UICC-AJCC classification. Survival data were collected and crosschecked using death and municipal registries. Data from patients with OAC in the general population were obtained from the Dutch cancer registry. We compared survival of patients with BO with neoplastic progression during surveillance with those of patients without neoplastic progression and patients with OAC in the general population.

RESULTS

53 patients with BO developed high-grade dysplasia or OAC during surveillance. Thirty-five (66%) were classified as stage 0, 14 (26%) as stage 1 and 4 (8%) as stage 2. OAC was diagnosed at an earlier stage during BO surveillance than in the general population (p<0.001). Survival of patients with BO with neoplastic progression was not significantly worse than those of patients without neoplastic progression and similar to survival of patients with stage 0 or stage 1 OAC in the general population.

CONCLUSIONS

OAC is detected at an earlier stage during BO surveillance than in the general population with good survival rates.

Magnitude of Missed Esophageal Adenocarcinoma After Barrett's Esophagus Diagnosis: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

A proportion of patients with Barrett's esophagus (BE) are diagnosed with esophageal adenocarcinoma (EAC) within 1 year of an endoscopic examination that produced negative findings. These cases of missed cancers have not been well studied, despite current surveillance strategies for BE. We performed a systematic review and meta-analysis to determine the magnitude of missed EAC in cohorts of patients with BE.

METHODS

We searched MEDLINE, EMBASE, and Web of Science from their inception to May 31, 2015 to identify cohort studies of adults with BE (baseline nondysplastic BE ± BE with low-grade dysplasia) and at least a 3-year follow-up period, providing data on missed and incident EACs (diagnosed within 1 year and diagnosed more than 1 year after the initial endoscopy in which BE was diagnosed, respectively). The main outcome measure was pooled proportion of missed and incident EACs (of all EACs detected after initial endoscopy) among BE cohorts, using a random effects model.

RESULTS

In a meta-analysis of 24 studies reporting on 820 missed and incident EACs, 25.3% were classified as missed (95% confidence interval: 16.4%-36.8%) and 74.7% as incident EACs (95% CI: 63.2%-83.6%), although there was substantial heterogeneity among studies (I2 = 74%). When the analysis was restricted to nondysplastic BE cohorts (15 studies), 23.9% of EACs were classified as missed (95% confidence interval: 15.3%-35.4%; I2 = 0%). In a meta-analysis of 10 studies with follow-up periods of ≥5 years (a total of 239 EACs), 22.0% were classified as missed (95% confidence interval: 8.7%-45.5%), with substantial heterogeneity (I2 = 68%).

CONCLUSIONS

Among adults with nondysplastic BE (or BE with low-grade dysplasia) at their index endoscopy and at least a 3-year follow-up period, 25% of EACs are diagnosed within 1 year after the index endoscopy. Additional resources should be allocated to detect missed EAC.

Gender difference in gastro-esophageal reflux diseases

The incidence of esophageal adenocarcinoma (EAC) has risen sharply in western countries over the past 4 decades. This type of cancer is considered to follow a transitional process that goes from gastro-esophageal reflux disease (GERD) to Barrett's esophagus (BE, a metaplastic condition of the distal esophagus), a precursor lesion and ultimately adenocarcinoma. This spectrum of GERD is strongly predominant in males due to an unidentified mechanism. Several epidemiologic studies have described that the prevalence of GERD, BE and EAC in women is closely related to reproductive status, which suggests a possible association with the estrogen level. Recently, we revealed in an in vivo study that the inactivation of mast cells by the anti-inflammatory function of estrogen may account for the gender difference in the GERD spectrum. Other studies have described the contribution of female steroid hormones to the gender difference in these diseases. Estrogen is reported to modulate the metabolism of fat, and obesity is a main risk factor of GERDs. Moreover, estrogen could confer esophageal epithelial resistance to causative refluxate. These functions of estrogen might explain the approximately 20-year delay in the incidence of BE and the subsequent development of EAC in women compared to men, and this effect may be responsible for the male predominance. However, some observational studies demonstrated that hormone replacement therapy exerts controversial effects in GERD patients. Nevertheless, the estrogen-related endocrine milieu may prevent disease progression toward carcinogenesis in GERD patients. The development of innovative alternatives to conventional acid suppressors may become possible by clarifying the mechanisms of estrogen.

Mechanisms of esophageal adenocarcinoma formation and approaches to chemopreventive intervention

The incidence of esophageal adenocarcinoma (EAC), a debilitating and highly lethal malignancy, has risen dramatically over the past 40 years in the United States and other Western countries. To reverse this trend, EAC prevention and early detection efforts by clinicians, academic researchers and endoscope manufacturers have targeted Barrett's esophagus (BE), the widely accepted EAC precursor lesion. Data from surgical, endoscopic and pre-clinical investigations strongly support the malignant potential of BE. For patients with BE, the risk of developing EAC has been estimated at 11- to 125-fold greater than that of the individual at average risk. Nevertheless, screening for BE in symptomatic patients (ie, with symptoms of reflux) and surveillance in patients diagnosed with BE have not had a substantial impact on the incidence, morbidity or mortality of EAC; the overwhelming majority of EAC patients are diagnosed without a pre-operative diagnosis of BE. This article will discuss the current state of the science of esophageal adenocarcinoma prevention, including ideas about carcinogenesis and its underlying genomic and molecular level mechanisms, and suggest strategies for a systems approach to targeted preventive management.

Surveillance in Patients With Barrett's Esophagus for Early Detection of Esophageal Adenocarcinoma: A Systematic Review and Meta-Analysis

Objectives:

Although endoscopic surveillance of patients with Barrett's esophagus (BE) has been widely implemented for early detection of esophageal adenocarcinoma (EAC), its justification has been debated. This systematic review aimed to evaluate benefits, safety, and cost effectiveness of surveillance for patients with BE.

Methods:

MEDLINE, EMBASE, EconLit, Scopus, Cochrane, and CINAHL were searched for published human studies that examined screening practices, benefits, safety, and cost effectiveness of surveillance among patients with BE. Reviewers independently reviewed eligible full-text study articles and conducted data extraction and quality assessment, with disagreements resolved by consensus. Random effects meta-analyses were performed to assess the incidence of EAC, EAC/high-grade dysplasia (HGD), and annual stage-specific transition probabilities detected among BE patients under surveillance, and relative risk of mortality among EAC patients detected during surveillance compared with those not under surveillance.

Results:

A total of 51 studies with 11,028 subjects were eligible; the majority were of high quality based on the Newcastle–Ottawa quality scale. Among BE patients undergoing endoscopic surveillance, pooled EAC incidence per 1,000 person-years of surveillance follow-up was 5.5 (95% confidence interval (CI): 4.2–6.8) and pooled EAC/HGD incidence was 7.7 (95% CI: 5.7–9.7). Pooled relative mortality risk among surveillance-detected EAC patients compared with nonsurveillance-detected EAC patients was 0.386 (95% CI: 0.242–0.617). Pooled annual stage-specific transition probabilities from nondysplastic BE to low-grade dysplasia, high-grade dysplasia, and EAC were 0.019, 0.003, and 0.004, respectively. There was, however, insufficient scientific evidence on safety and cost effectiveness of surveillance for BE patients.

Conclusions:

Our findings confirmed a low incidence rate of EAC among BE patients undergoing surveillance and a reduction in mortality by 61% among those who received regular surveillance and developed EAC. Because of knowledge gaps, it is important to assess safety of surveillance and health-care resource use and costs to supplement existing evidence and inform a future policy decision for surveillance programs.

Detection and characterization of early malignancy in the esophagus: what is the best management algorithm?

Barrett's esophagus is a known precursor for esophageal adenocarcinoma. Early detection of dysplasia provides a window of opportunity for curative intervention. Several image-enhanced technologies have been developed to improve visualization of neoplasia. These however have not been found to be superior to the standard four quadrant random biopsy protocol. Patients are risk-stratified based on the degree of dysplasia found on biopsies and undergo either surveillance or treatment. Endoscopic therapy has become the mainstay of treatment for early neoplasia.

Epidemiology of Barrett's Esophagus and Esophageal Adenocarcinoma

Barrett's esophagus (BE) is the precursor to esophageal adenocarcinoma (EAC), a disease with increasing burden in the Western world, especially in white men. Risk factors for BE include obesity, tobacco smoking, and gastroesophageal reflux disease (GERD). EAC is the most common form of esophageal cancer in the United States. Risk factors include GERD, tobacco smoking, and obesity, whereas nonsteroidal antiinflammatory drugs and statins may be protective. Factors predicting progression from nondysplastic BE to EAC include dysplastic changes on esophageal histology and length of the involved BE segment. Biomarkers have shown promise, but none are approved for clinical use.

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.

BOB CAT: A Large-Scale Review and Delphi Consensus for Management of Barrett's Esophagus With No Dysplasia, Indefinite for, or Low-Grade Dysplasia

OBJECTIVES

Barrett's esophagus (BE) is a common premalignant lesion for which surveillance is recommended. This strategy is limited by considerable variations in clinical practice. We conducted an international, multidisciplinary, systematic search and evidence-based review of BE and provided consensus recommendations for clinical use in patients with nondysplastic, indefinite, and low-grade dysplasia (LGD).

METHODS

We defined the scope, proposed statements, and searched electronic databases, yielding 20,558 publications that were screened, selected online, and formed the evidence base. We used a Delphi consensus process, with an 80% agreement threshold, using GRADE (Grading of Recommendations Assessment, Development and Evaluation) to categorize the quality of evidence and strength of recommendations.

RESULTS

In total, 80% of respondents agreed with 55 of 127 statements in the final voting rounds. Population endoscopic screening is not recommended and screening should target only very high-risk cases of males aged over 60 years with chronic uncontrolled reflux. A new international definition of BE was agreed upon. For any degree of dysplasia, at least two specialist gastrointestinal (GI) pathologists are required. Risk factors for cancer include male gender, length of BE, and central obesity. Endoscopic resection should be used for visible, nodular areas. Surveillance is not recommended for <5 years of life expectancy. Management strategies for indefinite dysplasia (IND) and LGD were identified, including a de-escalation strategy for lower-risk patients and escalation to intervention with follow-up for higher-risk patients.

CONCLUSIONS

In this uniquely large consensus process in gastroenterology, we made key clinical recommendations for the escalation/de-escalation of BE in clinical practice. We made strong recommendations for the prioritization of future research.

Risk stratification of patients with barrett's esophagus and low-grade dysplasia or indefinite for dysplasia

BACKGROUND & AIMS

In patients with Barrett's esophagus (BE), low-grade dysplasia (LGD) is a risk factor for esophageal adenocarcinoma (EAC), progressing at variable rates. Patients at higher risk for progression could benefit from intervention. We assessed rates of progression of LGD and indefinite for dysplasia (IND) and risk factors for progression to high-grade dysplasia (HGD) and EAC.

METHODS

We analyzed data from Cleveland Clinic Barrett's Registry on patients with BE and LGD or IND at least 1 year of follow-up from January 1, 2002 through December 31, 2012. Prevalent cases were those diagnosed at or within 1 year of the first endoscopy, and the rest were incident cases.

RESULTS

Among 299 patients with BE and LGD or IND, there were 32 cases of HGD and 10 cases of EAC during a follow-up period of 1577.4 patient-years. The annual incidence rates were 2.4% (95% confidence interval [CI], 1.7%-3.3%) for HGD, 0.6% (95% CI, 0.3%-1.2%) for EAC, and 2.7% (95% CI, 1.9%-3.6%) for HGD or EAC. The rates were higher in men than in women with BE and LGD or IND. Prevalent cases were 3-fold more likely to progress than incident cases. Multifocality and nodules were associated with higher risk of progression to HGD or EAC. None of the patients with IND at index biopsy developed EAC. For every 5-year increase in age, chance of regression increased by 7% (P = .04). Also, for every 1-cm increase in BE length, probability of regression decreased by 6% (P = .016). LGD at index biopsy was associated with 56% lower chance of regression compared with IND (P < .001).

CONCLUSIONS

On the basis of a database analysis of patients with BE, prevalent LGD, male sex, multifocality, and nodules were associated with higher risk for progression to EAC. Older age at LGD diagnosis, IND at index biopsy, and shorter BE length were associated with regression. These findings help in risk stratification of patients with BE and LGD or IND.

Acetic acid chromoendoscopy in Barrett's esophagus surveillance is superior to the standardized random biopsy protocol: results from a large cohort study (with video)

BACKGROUND

Currently, various advanced endoscopic techniques are available with varying success rates. These technologies are manufacturer dependent, which has financial implications in the current era of austerity. Acetic acid is a commonly available dye that has been used in the detection of neoplasia within Barrett's esophagus. It has been shown to be effective in detecting neoplasia in high-risk subgroups, but its efficacy in a low-prevalence surveillance population remains unproven.

OBJECTIVE

This study aimed to investigate the effectiveness of acetic acid chromoendoscopy in a Barrett's esophagus surveillance population. We aimed to compare the neoplasia yield of acetic acid chromoendoscopy (AAC) with the neoplasia yield from standardized random biopsy (SBP) protocol-guided biopsies in the routine surveillance of patients with Barrett's esophagus.

DESIGN

Retrospective cohort study.

SETTING

Tertiary referral hospital in the United Kingdom.

PATIENTS

Patients 18 years of age and older with a diagnosis of Barrett's esophagus undergoing surveillance gastroscopy.

INTERVENTIONS

AAC versus standardized random biopsy protocol (SBP) for Barrett's esophagus surveillance.

MAIN OUTCOME MEASUREMENTS

Neoplasia detection in 2 groups.

RESULTS

The overall neoplasia detection rates for all grades of neoplasia were 13 of 655 (2%) in the SBP-guided biopsy cohort and 41 of 327 (12.5%) in the AAC cohort (P = .0001). On per-patient analysis, a 6.5-fold gain in neoplasia detection was seen in the AAC cohort compared with the SBP cohort (0.13 vs 0.02, P = .000). In the SBP cohort, a total of 13 of 655 (2%) neoplasias were detected, of which 3 of 655 patients (0.5%) had low-grade dysplasia, 7 of 655 (1%) had high-grade dysplasia, and 3 of 655 (0.5%) were found to have superficial cancer (T1a/T1b). In the AAC cohort, a total of 41 of 327 neoplasias (12.5%) were found, of which 9 of 327 patients (2.7%) had low-grade dysplasia, 18 of 327 (5.5%) had high-grade dysplasia, and 14 of 327 (4.2%) were found to have superficial cancer. The number of biopsies required to detect 1 neoplasia was 15 times lower in the AAC cohort (40 biopsies) than in the SBP cohort (604 biopsies). On per-biopsy analysis, a 14.7-fold increase in neoplasia detection was seen in the AAC cohort per biopsy compared with the SBP cohort (0.025 vs 0.0017; P = .000).

LIMITATIONS

Not a randomized, controlled study.

CONCLUSIONS

Our study demonstrates that acetic acid detects more neoplasias than conventional protocol-guided mapping biopsies and requires 15 times fewer biopsies per neoplasia detected.

The patterns of reflux can affect regression of non-dysplastic and low-grade dysplastic Barrett's esophagus after medical and surgical treatment: a prospective case-control study

BACKGROUND

To date, therapeutic guidelines and pattern of reflux for patients with no-dysplasia (ND) or low-grade dysplasia (LGD) Barrett's esophagus (BE) remain unclear. We aimed to analyze pattern of reflux and regression of ND- or LGD-BE after medical and surgical treatment.

METHODS

We studied a cohort of ND- and LGD-BE patients who underwent laparoscopic total fundoplication and a cohort of ND- and LGD-BE patients managed medically. Patients were matched for age, sex, and disease duration. After 1 year of follow-up at least, all patients underwent upper endoscopy with esophageal biopsies to evaluate any histological changes, as well as manometry and impedance-pH-metry to re-assess reflux patterns.

RESULTS

Thirty-seven patients (20 LGD, 17 ND) undergoing laparoscopic fundoplication were enrolled and compared with 25 patients (13 LGD, 12 ND) managed with proton pump inhibitors (PPI). Laparoscopic fundoplication resulted in a better control of both acidic and weakly acidic reflux (P < 0.001) and was associated with a higher probability of reversion for LGD (P < 0.01). Esophageal motility did not differ between surgically and medically treated patients.

CONCLUSIONS

In patients with ND- or LGD-BE, laparoscopic fundoplication seems to warrant a better control of all kinds of refluxate and it is associated with a higher likelihood of reversion of both LGD- and ND-BE, compared with PPI therapy.

Incidence of esophageal adenocarcinoma in Barrett's esophagus with low-grade dysplasia: a systematic review and meta-analysis

BACKGROUND

The natural history of low-grade dysplasia (LGD) in patients with Barrett's esophagus (BE) is unclear.

OBJECTIVE

We performed a systematic review and meta-analysis of studies that reported the incidence of esophageal adenocarcinoma (EAC) and/or high-grade dysplasia (HGD) among patients with BE with LGD.

DESIGN

Systematic review and meta-analysis of cohort studies.

PATIENTS

Patients with BE-LGD, with mean cohort follow-up ≥ 2 years.

MAIN OUTCOME MEASUREMENTS

Pooled incidence rates with 95% confidence intervals (CI) of EAC and/or BE-HGD.

RESULTS

We identified 24 studies reporting on 2694 patients with BE-LGD, with 119 cases of EAC. Pooled annual incidence rates of EAC alone and EAC and/or HGD in patients with BE-LGD were 0.54% (95% CI, 0.32-0.76; 24 studies) and 1.73% (95% CI, 0.99-2.47; 17 studies). The results were stable across study setting and location and in high-quality studies. Substantial heterogeneity was observed, which could be explained by stratifying based on LGD/BE ratio as a surrogate for quality of pathology; the pooled annual incidence rates of EAC were 0.76% (95% CI, 0.44-1.09; 14 studies) for LGD/BE ratio <0.15 and 0.32% (95% CI, 0.07-0.58; 10 studies) for LGD/BE ratio >0.15. The annual rate of mortality not related to esophageal disease in patients with BE-LGD was 4.7% (95% CI, 3.2-6.2; 4 studies).

LIMITATIONS

Substantial heterogeneity was observed in the overall analysis.

CONCLUSION

The incidence of EAC among patients with BE-LGD is 0.54% annually. The LGD/BE ratio appears to explain the variation observed in the reported incidence of EAC in different cohorts. Conditions not related to esophageal disease are a major cause of mortality in patients with BE-LGD, although additional studies are warranted.

Development of a program to train physician extenders to perform transnasal esophagoscopy and screen for Barrett's esophagus

BACKGROUND & AIMS

Screening for Barrett's esophagus (BE) and esophageal adenocarcinoma is not recommended because it was not found to be cost effective. However, physician extenders (PEs) are able to perform unsedated procedures; their involvement might reduce the costs of BE screening. We examined the feasibility of training PEs to independently perform transnasal esophagoscopy (TNE) and screen patients for BE and measured their learning curve.

METHODS

Two PEs at a Veterans Affairs (VA) medical center underwent a structured didactic training program and observed nasopharyngoscopies before performing TNE under the supervision of attending endoscopists. Individual technical and cognitive components of TNE were rated on a 9-point structured scale. Learning curves were constructed using cumulative summation. Once the PEs were judged to be technically competent, each PE performed 10 independent videotaped TNEs, which were graded.

RESULTS

Both PEs identified anatomic landmarks after 18 consecutive procedures. PE1 and PE2 performed satisfactory nasal intubations after 20 and 25 procedures and esophageal intubations after 29 and 35 procedures, respectively. They acquired overall competence after supervised training on 43 and 47 procedures, respectively.

CONCLUSIONS

We developed a program at a VA medical center to train PEs to perform TNE to screen for BE. The PEs were able to perform TNE and recognize esophageal landmarks independently after a modest number of supervised procedures.

Carcinogenesis of Barrett's esophagus: a review of the clinical literature

Barrett's esophagus (BE) is a premalignant condition of esophageal adenocarcinoma (EAC). Although the incidence of BE has risen rapidly in the West, it is rare in Asia despite a recent increase in the prevalence of gastroesophageal reflux disease. Controversies over the definition of BE are presented because most cases show short-segment BE, especially ultra-short BE, in Asia. Here we review possible risk factors for the development of EAC, particularly possible roles of ethnicity, specialized intestinal metaplasia (SIM), BE length, and environmental factors, such as Helicobacter pylori infection and obesity. Additionally, we summarize recent studies on the effect of chemoprevention including proton pump inhibitors, nonsteroidal anti-inflammatory drugs or aspirin in order to reduce the risk of neoplastic progression in BE patients. Although substantial knowledge of risk factors of dysplasia/EAC in BE is shown, the risk for neoplastic development may be influenced by geographic variation, study population, the presence or absence of SIM or dysplasia at baseline, and the small number of BE patients investigated. Recently, the efficiency of surveillance for BE patients has been discussed from the standpoint of cost-effectiveness. It may be too difficult to draw conclusions because no randomized clinical trials of BE surveillance have been performed.

Magnifying endoscopy for the diagnosis of specialized intestinal metaplasia in short-segment Barrett’s esophagus

AIM: To determine whether magnified observation of short-segment Barrett’s esophagus (BE) is useful for the detection of specialized intestinal metaplasia (SIM).

METHODS: Thirty patients with suspected short-segment BE underwent magnifying endoscopy up to × 80. The magnified images were analyzed with respect to their pit-patterns, which were simultaneously classified into five epithelial types [I (small round), II (straight), III (long oval), IV (tubular), V (villous)] by Endo’s classification. Then, a 0.5% solution of methylene blue (MB) was sprayed over columnar mucosa. The patterns of the magnified image and MB staining were analyzed. Biopsies were obtained from the regions previously observed by magnifying endoscopy and MB chromoendoscopy.

RESULTS: Three of five patients with a type V (villous) epithelial pattern had SIM, whereas 21 patients with a non-type V epithelial patterns did not have SIM. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of pit-patterns in detecting SIM were 100%, 91.3%, 92.3%, 60% and 100%, respectively (P = 0.004). Three of the 12 patients with positive MB staining had SIM, whereas 14 patients with negative MB staining did not have SIM. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MB staining in detecting SIM were 100%, 60.9%, 65.4%, 25% and 100%, respectively (P = 0.085). The specificity and accuracy of pit-pattern evaluation were significantly superior compared with MB staining for detecting SIM by comparison with the exact McNemar’s test (P = 0.0391).

CONCLUSION: The magnified observation of a short-segment BE according to the mucosal pattern and its classification can be predictive of SIM.

Cause-specific mortality of people with Barrett's esophagus compared with the general population: a population-based cohort study

BACKGROUND & AIMS

Understanding the causes of death in people with Barrett's esophagus (BE) could guide evidence-based practice in the follow-up of these patients.

METHODS

We identified individuals diagnosed with BE in the UK's Clinical Practice Research Datalink and linked their information with that from England's Hospital Episode Statistics database. Eligible patients (N = 8448) were matched with individuals without BE for age, sex, and general practice (controls, N = 155,212). Causes of death were obtained from the UK's Office for National Statistics. Cox proportional hazard regression, excluding data from the first year of follow-up, was used to estimate hazard ratios and cumulative mortality. Absolute excess risks were calculated by subtracting cause-specific mortality values of controls from those of patients with BE.

RESULTS

Compared with the control population, patients with BE had increased risks of death from neoplasms and from respiratory and digestive causes but not from circulatory disorders. The annual mortality rate from esophageal cancer among patients with BE was 0.14%; 4.5% of deaths among these patients resulted from this cancer, leading to a cumulative 10-year risk of almost 2%. Nonetheless, the largest single cause of death among patients with BE was ischemic heart disease (5.6 per 1000 patients); 168 patients with BE died of this cause, nearly 4-fold the number that died of esophageal cancer.

CONCLUSIONS

Among patients with BE, approximately 2% will die of esophageal cancer within 10 years. However, patients with BE died more frequently of other causes, such as ischemic heart disease. Evidence-based strategies are available to prevent this disease and might be more cost-effective for reducing mortality among patients with BE.

Systemic sclerosis and the gut

Gastrointestinal involvement (GI) is increasingly recognized as a major cause of both morbidity and mortality in systemic sclerosis (SSc). GI complications are common, second only to skin involvement, and affect up to 90% of patients. Although treatment modalities have changed little for upper gut symptoms such as GI reflux, there are emerging treatment modalities for the common lower gut symptoms (constipation and fecal incontinence), which will be reviewed. The important link between reflux and interstitial lung disease in SSc is also addressed. The aim of this review is to help the clinician understand and manage GI symptoms in SSc.

Endoscopic therapy of Barrett esophagus

Barrett esophagus (BE) is a well-established premalignant condition for esophageal adenocarcinoma (EAC), a lethal cancer with a dismal survival rate. The current guidelines recommend surveillance of patients with BE to detect dysplasia or early cancer before the development of invasive EAC. Recently, endoscopic eradication therapies have been shown to be safe and effective in the treatment of BE-related high-grade dysplasia and early EAC. This article reviews the various treatment options for BE and discusses the current evidence and gaps in knowledge in the understanding of treatment of this condition. In addition, recommendations are provided in context to the recently published guidelines by the American Gastroenterological Association.

Potential benefits of pH 8.8 alkaline drinking water as an adjunct in the treatment of reflux disease

OBJECTIVES

At the cellular level, tissue-bound pepsin is fundamental to the pathophysiologic mechanism of reflux disease, and although the thresholds for laryngeal damage in laryngopharyngeal reflux and for esophageal damage in gastroesophageal reflux disease differ, both forms of damage are due to pepsin, which requires acid for its activation. In addition, human pepsin remains stable at pH 7.4 and may be reactivated by hydrogen ions from any source. Thus, most tap and bottled waters (typically pH 6.7 to 7.4) would not be expected to affect pepsin stability. The purposes of these in vitro studies were to investigate whether artesian well water containing natural bicarbonate (pH 8.8) might irreversibly denature (inactivate) human pepsin, and to establish its potential acid-buffering capacity.

METHODS

Laboratory studies were performed to determine whether human pepsin was inactivated by pH 8.8 alkaline water. In addition, the buffering capacity of the alkaline water was measured and compared to that of the two most popular commercially available bottled waters.

RESULTS

The pH 8.8 alkaline water irreversibly inactivated human pepsin (in vitro), and its hydrochloric acid-buffering capacity far exceeded that of the conventional-pH waters.

CONCLUSIONS

Unlike conventional drinking water, pH 8.8 alkaline water instantly denatures pepsin, rendering it permanently inactive. In addition, it has good acid-buffering capacity. Thus, the consumption of alkaline water may have therapeutic benefits for patients with reflux disease.

Management of low-grade dysplasia in Barrett's esophagus

PURPOSE OF REVIEW

This article discusses the various controversies that surround the management of low-grade dysplasia (LGD) in Barrett's esophagus.

RECENT FINDINGS

Data on the clinical course of LGD patients with regards to rates of progression to high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) are highly variable. Recent data suggest that the rate of progression to EAC may be similar to that of patients with nondysplastic Barrett's esophagus (0.4-0.5% per year). There is significant interobserver variability in the diagnosis of LGD even among expert gastrointestinal pathologists. Data on various endoscopic eradication therapies (EET) specifically in this patient population are limited. Eradication of LGD and intestinal metaplasia can be achieved by radiofrequency ablation as demonstrated in a randomized controlled trial. Although treatment appears to be durable for up to 3 years, progression to HGD and EAC can occur, highlighting the need for close endoscopic surveillance even after EET.

SUMMARY

There is a need to risk stratify Barrett's esophagus patients with LGD to identify patients most likely to progress using a reliable and objective system that incorporates clinical features, advanced imaging techniques and biomarkers. If such a high risk group could be identified, they may benefit from EET, whereas, the majority may be managed conservatively.

African Americans with Barrett's esophagus are less likely to have dysplasia at biopsy

BACKGROUND

Barrett's Esophagus (BE) is a pre-malignant condition. Limited data on BE dysplasia prevalence exists among United States ethnic groups.

AIM

The purpose of this study was to determine if the frequency of BE with dysplasia varies among the major ethnic groups presenting to our institution.

METHODS

The University of Florida-Jacksonville endoscopy database was searched for all cases of endoscopic BE from September 2002 to August 2007. Histologic BE was diagnosed if salmon colored esophageal mucosa was endoscopically seen at least 1 cm above the top of the gastric folds and biopsy revealed intestinal metaplasia with Alcian blue-containing goblet cells. Demographic data collected for all included: age at diagnosis, ethnicity, sex, previous history of esophageal reflux, atypical manifestations (chronic cough, aspiration), endoscopic length of BE, presence or absence of hiatal hernia, esophageal stricture or ulcer, and presence or absence of dysplasia.

RESULTS

Salmon colored esophageal mucosa was observed in 405 of 7,308 patients (5.5%) and histologically confirmed in 115 of 405 patients (28%) reflecting an overall prevalence of BE of 115/7308 (1.6%) in this cohort. Ethnic distribution of histologic BE patients was as follows: 95 (83%) non-Hispanic white (nHw), 16 (14%) African American (AA) and 4 (3%) other. Long segment BE (LSBE) and any form of dysplasia was observed less frequently in AA than nHw (LSBE: 12% vs. 26% and dysplasia: 0% vs. 7%).

CONCLUSIONS

LSBE and dysplasia are less frequent in AA than nHw. Studies in AA with BE may illustrate factors limiting dysplasia and LSBE risk.

Molecular mechanisms of Barrett's esophagus and adenocarcinoma

The following on molecular mechanisms of Barrett's esophagus and adenocarcinoma contains commentaries on the mechanism of bile and gastric acid induced damage; the roles of BMP-4 and CDX-2 in the development of intestinal metaplasia; the transcription factors driving intestinalization in Barrett's esophagus; the contribution of bone marrow to metaplasia and adenocarcinoma; activation and inactivation of transcription factors; and a novel study design targeting molecular pathways in Barrett's esophagus.

Incidence of adenocarcinoma among patients with Barrett's esophagus

BACKGROUND

Accurate population-based data are needed on the incidence of esophageal adenocarcinoma and high-grade dysplasia among patients with Barrett's esophagus.

METHODS

We conducted a nationwide, population-based, cohort study involving all patients with Barrett's esophagus in Denmark during the period from 1992 through 2009, using data from the Danish Pathology Registry and the Danish Cancer Registry. We determined the incidence rates (numbers of cases per 1000 person-years) of adenocarcinoma and high-grade dysplasia. As a measure of relative risk, standardized incidence ratios were calculated with the use of national cancer rates in Denmark during the study period.

RESULTS

We identified 11,028 patients with Barrett's esophagus and analyzed their data for a median of 5.2 years. Within the first year after the index endoscopy, 131 new cases of adenocarcinoma were diagnosed. During subsequent years, 66 new adenocarcinomas were detected, yielding an incidence rate for adenocarcinoma of 1.2 cases per 1000 person-years (95% confidence interval [CI], 0.9 to 1.5). As compared with the risk in the general population, the relative risk of adenocarcinoma among patients with Barrett's esophagus was 11.3 (95% CI, 8.8 to 14.4). The annual risk of esophageal adenocarcinoma was 0.12% (95% CI, 0.09 to 0.15). Detection of low-grade dysplasia on the index endoscopy was associated with an incidence rate for adenocarcinoma of 5.1 cases per 1000 person-years. In contrast, the incidence rate among patients without dysplasia was 1.0 case per 1000 person-years. Risk estimates for patients with high-grade dysplasia were slightly higher.

CONCLUSIONS

Barrett's esophagus is a strong risk factor for esophageal adenocarcinoma, but the absolute annual risk, 0.12%, is much lower than the assumed risk of 0.5%, which is the basis for current surveillance guidelines. Data from the current study call into question the rationale for ongoing surveillance in patients who have Barrett's esophagus without dysplasia. (Funded by the Clinical Institute, University of Aarhus, Aarhus, Denmark.).

Risk factors for progression of low-grade dysplasia in patients with Barrett's esophagus

BACKGROUND & AIMS

Data vary on the progression of low-grade dysplasia (LGD) in patients with Barrett's esophagus (BE); in patients with LGD, we investigated the incidence of high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) and compared progression in patients with different forms of LGD (prevalent vs incident and multifocal vs unifocal). We assessed the effects of consensus diagnosis of LGD on progression rates to HGD and EAC among expert pathologists.

METHODS

In a multicenter outcomes project, 210 patients with BE and LGD (classified as incident, prevalent, or persistent) were included. Patients were followed up for an average of 6.2 years (959.6 patient-years). Persistent LGD was defined as detection of LGD on ≥2 consecutive occasions during the follow-up period and extent as either unifocal (LGD at one level of BE segment) or multifocal (>1 level). Histology specimens were reviewed by 2 blinded pathologists.

RESULTS

Six patients developed EAC (incidence of 0.44%/year), and 21 developed HGD (incidence of 1.6%/year). The incidence of the combination of HGD and EAC was 1.83%/year. There were no associations between presence of prevalent, incident, or persistent LGD and the extent of LGD with progression rates. Based on consensus diagnosis of 88 reviewed specimens, there was no difference in the progression of LGD to either EAC (the incidence based on analyses by the local pathologist was 0.18%/year, the incidence when there was agreement between the local and one central pathologist was 0.21%/year, and the incidence when all 3 pathologists were in agreement was 0.39%/year) or combined HGD and EAC (0.94%/year, 0.87%/year, and 0.84%/year, respectively).

CONCLUSIONS

Overall, patients with BE and LGD have a low annual incidence of EAC, similar to nondysplastic BE. There are no risk factors for progression and there is significant interobserver variation in diagnosis, even among expert pathologists.

Evaluation of difluoromethylornithine for the chemoprevention of Barrett's esophagus and mucosal dysplasia

Patients with Barrett's esophagus (BE) and dysplasia are candidates for chemopreventive strategies to reduce cancer risk. We determined the effects of difluoromethylornithine (DMFO) on mucosal polyamines, gene expression, and histopathology in BE. Ten patients with BE and low-grade dysplasia participated in a single-arm study of DFMO (0.5 g/m(2)/d) given continuously for 6 months. Esophagoscopy with biopsies was conducted at baseline, 3, 6, and 12 months. Dysplasia was graded by a gastrointestinal pathologist. Audiology was assessed (at baseline and at 6 months). Mucosal polyamines were measured by high-performance liquid chromatography. Microarray-based gene expression was analyzed using a cDNA two-color chip. DFMO suppressed levels of the polyamines putrescine (P = 0.02) and spermidine (P = 0.02) and the spermidine/spermine ratio (P < 0.01) in dysplastic BE (6 months vs. baseline) that persisted at 6 months following drug cessation. Among the top 25 modulated genes, we found those regulating p53-mediated cell signaling (RPL11), cell-cycle regulation (cyclin E2), and cell adhesion and invasion (Plexin1). DFMO downregulated Krüppel-like factor 5 (KLF5), a transcription factor promoting cell proliferation, and suppressed RFC5 whose protein interacts with proliferating cell nuclear antigen. Histopathology showed regression of dysplasia (n = 1), stable disease (n = 8), and progression to high-grade dysplasia (n = 1). Polyamines were suppressed in the responder to a greater extent than in stable cases. DFMO was well tolerated, and one patient had subclinical, unilateral ototoxicity. DFMO suppressed mucosal polyamines and modulated genes that may be mechanistically related to its chemopreventive effect. Further study of DFMO for the chemoprevention of esophageal cancer in BE patients is warranted.