Clinical Outcomes Following Recurrence of Intestinal Metaplasia After Successful Treatment of Barrett's Esophagus With Radiofrequency Ablation

Multi-focal dysplasia is associated with high recurrence rates after successful ablation of dysplastic Barrett's esophagus

BACKGROUND & AIMS

Barrett's esophagus (BE) might recur after complete eradication of intestinal metaplasia (CEIM). We investigated  factors associated with recurrence of BE after successful Radiofrequency ablation (RFA).

METHODS

A longitudinal study of BE patients with dysplasia treated with RFA from 2014 to 2021 in two large referral centers. Recurrence was identified in histologic specimens. Factors associated with post-RFA recurrence were analyzed using Cox regression analysis.

RESULTS

A total of 728 patients with BE were identified, 118 had underwent RFA, and 113 had sufficient follow up time. Mean age was 63.7 (±11.7) years, 73.5% were males, 59.3% had long segment of BE, and 30.1% had multifocal dysplasia. During 340.8 patient-years of follow-up, 15 patients (13.3%) had recurrence of BE, which represent an incidence rate of 4.41% per patient-year. Incidence rate of recurrence with dysplasia was 1.17% per patient-year. Multifocal dysplasia, number of RFA sessions, and endoscopic resection before RFA were associated with risk of recurrence in univariate analysis. However, in cox regression analysis only multifocal dysplasia (HR 10.99; 95% CI 2.83-22.62, p = 0.001) was associated with post-RFA recurrence.

CONCLUSION

Total recurrence rates after CEIM are low, and multifocal dysplasia before the ablative therapy is significantly associated with BE recurrence after CEIM. Patients with multifocal dysplasia should be monitored rigorously after successful ablation.

Diagnosis and management of Barrett esophagus: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

MR1 : ESGE recommends the following standards for Barrett esophagus (BE) surveillance:- a minimum of 1-minute inspection time per cm of BE length during a surveillance endoscopy- photodocumentation of landmarks, the BE segment including one picture per cm of BE length, and the esophagogastric junction in retroflexed position, and any visible lesions- use of the Prague and (for visible lesions) Paris classification- collection of biopsies from all visible abnormalities (if present), followed by random four-quadrant biopsies for every 2-cm BE length.Strong recommendation, weak quality of evidence. MR2:  ESGE suggests varying surveillance intervals for different BE lengths. For BE with a maximum extent of ≥ 1 cm and < 3 cm, BE surveillance should be repeated every 5 years. For BE with a maximum extent of ≥ 3 cm and < 10 cm, the interval for endoscopic surveillance should be 3 years. Patients with BE with a maximum extent of ≥ 10 cm should be referred to a BE expert center for surveillance endoscopies. For patients with an irregular Z-line/columnar-lined esophagus of < 1 cm, no routine biopsies or endoscopic surveillance are advised.Weak recommendation, low quality of evidence. MR3:  ESGE suggests that, if a patient has reached 75 years of age at the time of the last surveillance endoscopy and/or the patient's life expectancy is less than 5 years, the discontinuation of further surveillance endoscopies can be considered. Weak recommendation, very low quality of evidence. MR4:  ESGE recommends offering endoscopic eradication therapy using ablation to patients with BE and low grade dysplasia (LGD) on at least two separate endoscopies, both confirmed by a second experienced pathologist.Strong recommendation, high level of evidence. MR5:  ESGE recommends endoscopic ablation treatment for BE with confirmed high grade dysplasia (HGD) without visible lesions, to prevent progression to invasive cancer.Strong recommendation, high level of evidence. MR6:  ESGE recommends offering complete eradication of all remaining Barrett epithelium by ablation after endoscopic resection of visible abnormalities containing any degree of dysplasia or esophageal adenocarcinoma (EAC).Strong recommendation, moderate quality of evidence. MR7:  ESGE recommends endoscopic resection as curative treatment for T1a Barrett's cancer with well/moderate differentiation and no signs of lymphovascular invasion.Strong recommendation, high level of evidence. MR8:  ESGE suggests that low risk submucosal (T1b) EAC (i. e. submucosal invasion depth ≤ 500 µm AND no [lympho]vascular invasion AND no poor tumor differentiation) can be treated by endoscopic resection, provided that adequate follow-up with gastroscopy, endoscopic ultrasound (EUS), and computed tomography (CT)/positrion emission tomography-computed tomography (PET-CT) is performed in expert centers.Weak recommendation, low quality of evidence. MR9:  ESGE suggests that submucosal (T1b) esophageal adenocarcinoma with deep submucosal invasion (tumor invasion > 500 µm into the submucosa), and/or (lympho)vascular invasion, and/or a poor tumor differentiation should be considered high risk. Complete staging and consideration of additional treatments (chemotherapy and/or radiotherapy and/or surgery) or strict endoscopic follow-up should be undertaken on an individual basis in a multidisciplinary discussion.Strong recommendation, low quality of evidence. MR10 A: ESGE recommends that the first endoscopic follow-up after successful endoscopic eradication therapy (EET) of BE is performed in an expert center.Strong recommendation, very low quality of evidence. B:  ESGE recommends careful inspection of the neo-squamocolumnar junction and neo-squamous epithelium with high definition white-light endoscopy and virtual chromoendoscopy during post-EET surveillance, to detect recurrent dysplasia.Strong recommendation, very low level of evidence. C:  ESGE recommends against routine four-quadrant biopsies of neo-squamous epithelium after successful EET of BE.Strong recommendation, low level of evidence. D:  ESGE suggests, after successful EET, obtaining four-quadrant random biopsies just distal to a normal-appearing neo-squamocolumnar junction to detect dysplasia in the absence of visible lesions.Weak recommendation, low level of evidence. E:  ESGE recommends targeted biopsies are obtained where there is a suspicion of recurrent BE in the tubular esophagus, or where there are visible lesions suspicious for dysplasia.Strong recommendation, very low level of evidence. MR11:  After successful EET, ESGE recommends the following surveillance intervals:- For patients with a baseline diagnosis of HGD or EAC:at 1, 2, 3, 4, 5, 7, and 10 years after last treatment, after which surveillance may be stopped.- For patients with a baseline diagnosis of LGD:at 1, 3, and 5 years after last treatment, after which surveillance may be stopped.Strong recommendation, low quality of evidence.

Hybrid Argon Plasma Coagulation for Barrett's Esophagus and for Colonic Mucosal Resection-A Systematic Review and Meta-Analysis

Hybrid argon plasma coagulation (hAPC) is a novel technique that combines conventional argon plasma coagulation and waterjet submucosal expansion. The aims of this metanalysis were to evaluate the efficacy and safety of hAPC in the setting of Barret's esophagus (BE) ablation and as an adjunct to colonic endoscopic mucosal resection (EMR). Four electronic databases were searched, and the results were analyzed by two independent authors. Random-effects meta-analyses of the proportions of endoscopic and histologic remission (for BE), recurrence, and post-procedure adverse events were performed using R. Studies' reporting quality was also assessed. From the 979 identified records, 13 studies were included (10 regarding BE and three colonic EMR). The pooled percentages of endoscopic and histologic remission after hAPC for BE were 95% (95% confidence interval [CI] 91-99, I² = 34) and 90% (95%CI 84-95, I² = 46), respectively, while major adverse events and recurrence were registered in 2% (95%CI 0-5, I² = 41) and 11% (95%CI 2-27, I² = 11), respectively. Concerning hAPC-assisted EMR, the pooled percentages of major adverse events and recurrence were 5% (95%CI 2-10, I² = 0) and 1% (95%CI 0-3, I² = 40). Evidence suggests that the main advantages of hAPC are the increase in safety in the setting of BE ablation and the reduction of local recurrence after colonic EMR. Trials comparing hAPC with standard strategies are required to support its use for these indications.

Intestinal metaplasia in progression of Barrett's esophagus to esophageal adenocarcinoma

The incidence of esophageal adenocarcinoma (EAC) has been increasing year by year. The prognosis of EAC is poor, and the 5-year survival rate is less than 20%. Barrett's esophagus (BE) is the only known precancerous lesion of EAC. BE with intestinal metaplasia (IM) has a higher risk of progressing to EAC. Exploring the mechanism of IM and finding targeted therapeutic targets for BE has become an important measure for tumor prevention. Bile acid reflux is considered an important factor in the occurrence of IM and promotes the progression of BE to EAC. However, the molecular regulatory mechanism of bile reflux induced IM and carcinogenesis remains unclear. This article reviews the environment, significance, and cell origin theory of IM, toxic effects of bile reflux, and molecular changes of IM progression to tumor, aiming to improve clinicians' understanding of IM in BE and provide evidence for early intervention of BE and prevention and treatment of EAC.

Surveillance After Treatment of Barrett's Esophagus Benefits Those With High-Grade Dysplasia or Intramucosal Cancer Most

INTRODUCTION

Endoscopic eradication therapy with radiofrequency ablation (RFA) and endoscopic mucosal resection is a safe and effective treatment for Barrett's esophagus. Although the outcomes of surveillance endoscopy after successful endoscopic eradication therapy have been described, no previous studies have modeled the natural history or the effect of surveillance endoscopy after successful ablation to prevent progression to invasive esophageal adenocarcinoma.

METHODS

The US RFA Registry is a multicenter registry consisting of patients treated with RFA for Barrett's esophagus at 148 institutions (113 community-based and 35 academic-affiliated). The authors fit models to impute the natural history of recurrence and neoplastic progression after any recurrence or retreatment. Natural history estimates of invasive adenocarcinoma after ablation therapy were compared with as-treated estimates at 5 years to derive the preventive risk difference for surveillance.

RESULTS

Natural history estimates for the postablation progression of high-grade dysplasia (HGD) or intramucosal adenocarcinoma to invasive adenocarcinoma after treatment were 6.3% at 5 years compared with 1.3% for low-grade dysplasia (LGD). The natural history model found a much higher preventative risk difference for surveillance for HGD/intramucosal adenocarcinoma (-4.8%), compared with LGD (-1.1%). The numbers needed to surveil at 5 years were 21 and 90 for these groups, respectively, to prevent one case of invasive esophageal adenocarcinoma, making surveillance after successful ablation of baseline HGD more than 4 times as effective at preventing invasive cancer than after successful ablation of baseline LGD.

DISCUSSION

Endoscopic surveillance after successful ablation of baseline HGD or intramucosal cancer is much more effective than surveillance after successful treatment of baseline LGD in averting invasive adenocarcinoma. Although the modest benefits of surveillance for treated LGD may be greater than the risks for patients at average risk for adverse effects of endoscopy, clinicians should concentrate on retaining patients with baseline HGD or cancer in endoscopic surveillance programs.

Today's Mistakes and Tomorrow's Wisdom in Endoscopic Treatment and Follow-Up of Barrett's Esophagus

BACKGROUND

Endoscopic therapy has replaced esophagectomy for the management of early Barrett's neoplasia, allowing for the curative treatment of intramucosal adenocarcinoma, dysplastic Barrett's esophagus (BE), and the prevention of metachronous recurrences.

SUMMARY

Endoscopic therapy relies on the resection of any visible lesion, suspicious of harboring cancer, followed by the eradication of the residual BE, potentially harboring dysplastic foci. Currently, endoscopic mucosal resection (EMR) using the multiband mucosectomy technique is the gold standard for the resection of visible lesions. Endoscopic submucosal dissection (ESD) is feasible with comparable complication rates to EMR, but longer procedural times. It is still limited to EMR failures or suspected submucosal adenocarcinoma. Eradication of residual BE mainly relies on radiofrequency ablation, with over 90% efficacy in expert centers. Despite initial complete eradication of BE, intestinal metaplasia and dysplasia recur in time, justifying prolonged endoscopic surveillance.

KEY MESSAGES

The first step of the therapeutic endoscopy for BE is a careful diagnostic evaluation, searching for visible(s) lesion(s). EMR is the recommended resection technique for visible lesions. ESD has not demonstrated its superiority on EMR in routine practice. Endoscopic follow-up after Barrett's eradication therapy is mandatory.

Nitric oxide could promote development of Barrett's esophagus by S-nitrosylation-induced inhibition of Rho-ROCK signaling in esophageal fibroblasts

Barrett's esophagus arises in the process of wound healing in distal esophageal epithelium damaged by gastroesophageal reflux disease. Differentiation of fibroblast into myofibroblasts, a smooth muscle cell-like phenotype and tissue contraction are crucial processes in wound healing. No study has evaluated mechanism by which luminal esophageal nitric oxide (NO) affect Rho-associated coiled coil-forming protein kinase (Rho-ROCK) signaling pathway, a key factor of tissue contraction, in stromal fibroblasts to develop Barrett's esophagus. Using esophageal fibroblasts, we performed collagen-based cell contraction assays and evaluated influence of Rho-ROCK signaling in the exposure to acidic bile salts and NOC-9, which is an NO donor. We found that enhanced cell contraction induced by acidic bile salts was inhibited by NO, accompanied by decrease in phosphorylated myosin light chain expression and stress fiber formation. NO directly S-nitrosylated GTP-RhoA and consequently blocked Rho-ROCK signaling. Moreover, exposure to NO and Y27632, a Rho-ROCK signaling inhibitor, decreased α-SMA expression and increased bone morphogenetic protein-4 (BMP4) expression and secretion. These findings could account for the increased expression of BMP4 in the columnar epithelial cells and stromal fibroblasts in human Barrett's esophagus. NO could impair wound contraction by blocking the Rho-ROCK signaling pathway and promote the development of Barrett's esophagus.NEW & NOTEWORTHY Barrett's esophagus is the condition where esophageal epithelium damaged by gastroesophageal reflux disease (GERD) is abnormally healed via replacing of metaplastic columnar epithelium, but very few studies have conducted focusing wound healing in the development of Barrett's esophagus. Esophageal luminal nitric oxide inhibits Rho-ROCK signaling pathway in esophageal fibroblasts, which leads to delay tissue contraction, a pivotal step in proper wound healing. Moreover, this inhibition increases tissue BMP4 expression. Impaired wound healing could be related to Barrett's esophagus.

Chemoprevention in Barrett's esophagus and esophageal adenocarcinoma

There has been a dramatic increase in the incidence of Barrett's esophagus and esophageal adenocarcinoma over the past several decades with a continued rise expected in the future. Several strategies have been developed for screening and surveillance of patients with Barrett's esophagus and endoscopic treatment of Barrett's associated dysplasia and early esophageal cancer; however, they have not made a substantial impact on the incidence of cancer. Herein, chemoprevention becomes an attractive idea for reducing the incidence of cancer in Barrett's patients. Several agents appear promising in preclinical and observational studies but very few have been evaluated in randomized controlled trials. Strongest evidence to date is available for proton-pump inhibitors and Aspirin that have been evaluated in a large randomized controlled trial. Other agents such as statins, metformin, ursodeoxycholic acid, and dietary supplements have insufficient evidence for chemoprevention in Barrett's patients.

Antireflux and Endoscopic Therapies for Barrett Esophagus and Superficial Esophageal Neoplasia

Barrett esophagus (BE), defined as intestinal metaplasia of the distal esophageal mucosa, typically results from chronic gastroesophageal reflux disease and is the only known precursor of esophageal adenocarcinoma. The standard of care for the management of early esophageal neoplasia in the setting of BE has changed drastically over the past 15 years. Further investigation into diagnostic and therapeutic adjuncts will continue to improve our ability to control or cure BE before its advancement to a life-threatening malignancy.

Clinical significance of recurrent gastroesophageal junction intestinal metaplasia after endoscopic eradication of Barrett's esophagus

BACKGROUND AND AIMS

After endoscopic eradication of Barrett's esophagus (BE), recurrence of intestinal metaplasia at the gastroesophageal junction (GEJIM) is common. The clinical significance of this finding is unclear. We assessed whether recurrent GEJIM is associated with increased risk of subsequent dysplasia and whether endoscopic treatment lowers this risk.

METHODS

A retrospective, multicenter, cohort study was performed of treated BE patients who achieved complete eradication of intestinal metaplasia (IM). Postablation follow-up was performed at standard intervals. Recurrent GEJIM was defined as nondysplastic IM on gastroesophageal junction biopsy specimens without endoscopic evidence of BE. Patients were categorized as "never-GEJIM," "GEJIM-observed," or "GEJIM-treated." Endoscopic treatment for recurrent GEJIM was at the endoscopists' discretion. The primary outcome was dysplasia recurrence. Analyses were performed using log-rank tests and Cox proportional hazards modeling.

RESULTS

Six hundred thirty-three patients were analyzed; median follow-up was 47 months (interquartile range, 24-69). Most patients (81%) had high-grade dysplasia or intramucosal adenocarcinoma before treatment. Dysplasia recurrence was 2.2% per year. GEJIM-observed patients had the lowest rate of recurrence (.6%/y) followed by GEJIM-treated (2.2%/y) and never-GEJIM (2.6%/y) (log-rank P = .07). In multivariate analyses, compared with never-GEJIM, the risk of dysplasia recurrence was significantly lower in GEJIM-observed patients (adjusted hazard ratio, .19; 95% confidence interval, .05-.81) and not different in GEJIM-treated patients (adjusted hazard ratio, .81; 95% confidence interval, .39-1.67). Older age and longer initial BE length were independently associated with recurrence.

CONCLUSIONS

Recurrent GEJIM after endoscopic eradication of BE was not associated with an increased risk of subsequent dysplasia. Future studies are warranted to determine if observation is appropriate for this finding.

Outcomes of radiofrequency ablation by manual versus self-sizing circumferential balloon catheters for the treatment of dysplastic Barrett's esophagus: a multicenter comparative cohort study

BACKGROUND AND AIMS

Radiofrequency ablation (RFA) is the preferred ablative modality for treating dysplastic Barrett's esophagus. The recently introduced self-sizing circumferential ablation catheter eliminates the need for a sizing balloon. Although it enhances efficiency, outcomes have not been compared with the previous manual-sizing catheter. We evaluated the comparative safety and efficacy of these 2 ablation systems in a large, multicenter cohort.

METHODS

Patients undergoing RFA at 3 tertiary care centers from 2005 to 2018 were included. Circumferential RFA was performed in a standard fashion, followed by focal RFA as needed. Outcomes were compared between the self-sizing and manual-sizing groups. The primary outcome was the rate of adverse events, including strictures, perforation, and bleeding. Secondary outcomes were procedure time and treatment efficacy, as assessed by rates and time to complete eradication of dysplasia (CE-D) and intestinal metaplasia (CE-IM).

RESULTS

Three hundred eighteen patients were included, 90 (28.3%) treated with the self-sizing catheter and 228 (71.7%) with the manual-sizing catheter. Twenty-one patients (6.6%) developed strictures (8 [8.9%] in the self-sizing group and 13 [5.7%] in the manual-sizing group, P = .32). Of the self-sizing strictures, 75% occurred at the 12J dose before widespread adoption of the current 10J treatment standard. One patient developed bleeding, and no perforations were encountered. Procedure time was significantly shorter in the self-sizing group. No significant differences were observed in rates of and time to CE-D and CE-IM.

CONCLUSIONS

These findings suggest that both systems are comparable in safety and efficacy. The use of the self-sizing system may enhance the efficiency of RFA for treating dysplastic Barrett's esophagus.

Reflux Control After Barrett’s Esophagus Ablation

Esophageal adenocarcinoma (EAC) is difficult to treat and carries a poor prognosis. Barrett’s esophagus, which develops from long-standing gastroesophageal reflux disease, is the only known precursor to EAC. Endoscopic eradication therapy is a major advancement in the treatment of dysplastic Barrett’s esophagus and early EAC; however, failure to eradicate disease and a high rate of recurrence with risk of progression currently remain unacceptably high with the use of acid suppressive medication for reflux. Herein, we describe the physiology of gastroesophageal reflux and review the current literature on endoscopic eradication therapy for Barrett’s esophagus. We summarize that antireflux surgery for reflux control as an adjunct to endoscopic eradication therapy may decrease the need for multiple endoscopic sessions (to achieve eradication), decrease the risk for recurrence/progression, and potentially decrease the need for surveillance.

A Practical Approach to Refractory and Recurrent Barrett's Esophagus

Endoscopic eradication therapy (EET) is recommended for patients with Barrett's esophagus (BE)-associated neoplasia and is effective in achieving complete eradication of intestinal metaplasia (CE-IM). However, BE that is refractory to EET, defined as partial or no improvement in dysplasia after less than or equal to 3 ablative sessions, and the development of recurrence post-EET is not uncommon. Identification of refractory BE or recurrent intestinal metaplasia should prompt esophageal physiologic testing and modification of antireflux strategy, as appropriate. In patients who ultimately fail standard EET despite optimization of reflux control, salvage EET with alternate modalities may need to be considered.

Optimizing Outcomes with Radiofrequency Ablation of Barrett's Esophagus: Candidates, Efficacy and Durability

The treatment of early Barrett's esophagus (BE) has undergone a paradigm shift from surgical subtotal esophagectomy to organ-saving endoluminal treatment. Over the past 15 years, several high-quality studies were conducted to assess safe oncological outcome of endoscopic resection of mucosal adenocarcinoma and high-grade dysplasia. It became clear that add-on ablative therapy with radiofrequency ablation (RFA) significantly reduces recurrence risk of neoplasia after resection. In this review, we highlight the most essential elements to optimize outcomes of RFA of BE, addressing the correct indication and patient selection in combination with the most efficient and safest treatment protocols to obtain long-term durability.

Recurrence Is Rare Following Complete Eradication of Intestinal Metaplasia in Patients With Barrett's Esophagus and Peaks at 18 Months

BACKGROUND & AIMS

There have been few studies describing the long-term durability of complete eradication of intestinal metaplasia (CE-IM) in patients with Barrett's esophagus (BE)-related neoplasia who received endoscopic eradication therapy (EET). Data are needed to guide surveillance interval protocols and identify patients at risk for recurrence. We assessed the rate of recurrence of intestinal metaplasia and dysplasia, histologic features, and outcomes after recurrence of CE-IM, and identified factors associated with recurrence.

METHODS

We performed a prospective study of 807 patients with BE who underwent EET, which produced CE-IM, at 4 tertiary-care referral centers, from January 2013 to October 2018. Kaplan-Meier estimates of cumulative incidence rates (IR) of recurrence were calculated for up to 5 years following CE-IM and were stratified by baseline level of histology. Density estimates of recurrence were used to determine the change in the rate of recurrence over time. We conducted logistic regression analysis to identify factors associated with recurrence.

RESULTS

Intestinal metaplasia recurred in 121 patients (15%; IR, 5.2/100 person-years), and dysplasia recurred in 41 patients (5.1%; IR, 1.8/100 person-years), after a median follow-up time of 2317 person-years. The rate of recurrence was not constant and the time to any recurrence converged to a normal distribution; recurrences peaked at 1.6 y after patients had CE-IM. Baseline high-grade dysplasia or intramucosal cancer (adjusted odds ratio [aOR], 4.19), presence of reflux symptoms (aOR, 12.1) or hiatal hernia (aOR, 13.8), and number of sessions required to achieve CE-IM (aOR, 1.8) were associated with recurrence.

CONCLUSIONS

In a prospective study of a large cohort of patients with BE undergoing EET, we found a low rate of recurrence after CE-IM. The rate of recurrence peaked at 1-2 y after CE-IM. These findings indicate that aggressive surveillance might not be necessary more than 1 y after CE-IM and should be considered in surveillance guidelines. Clinicaltrials.gov no: NCT02634645.

Approach to the Post-Ablation Barrett's Esophagus Patient

Because of the rising incidence and lethality of esophageal adenocarcinoma, Barrett's esophagus (BE) is an increasingly important premalignant target for cancer prevention. BE-associated neoplasia can be safely and effectively treated with endoscopic eradication therapy (EET), incorporating tissue resection and ablation. Because EET has proliferated, managing patients after complete eradication of intestinal metaplasia has taken on increasing importance. Recurrence after complete eradication of intestinal metaplasia occurs in 8%-10% of the patients yearly, and the incidence may remain constant over time. Most recurrences occur at the gastroesophageal junction, whereas those in the tubular esophagus are endoscopically visible and distally located. A simplified biopsy protocol limited to the distal aspect of the BE segment, in addition to gastroesophageal junction sampling, may enhance efficiency and cost without significantly reducing recurrence detection. Similarly, research suggests that current surveillance intervals may be excessively frequent, failing to reflect the cancer risk reduction of EET. If validated, longer surveillance intervals could reduce the burden of resource-intensive endoscopic surveillance. Several important questions in post-EET management remain unanswered, including surveillance duration, the significance of gastric cardia intestinal metaplasia, and the role of advanced imaging and nonendoscopic sampling techniques in detecting recurrence. These merit further research to enhance quality of care and promote a more evidence-based approach.

Radiofrequency Ablation of Barrett's Esophagus: Have We Gone Too Far, or Not Far Enough?

PURPOSE OF REVIEW

Barrett's esophagus (BE) is a premalignant condition of the esophagus associated with an increased risk for esophageal adenocarcinoma (EAC). Radiofrequency ablation (RFA) is a safe and effective first-line treatment for dysplastic BE and early stage EAC. This report reviews clinically relevant evidence published over the last 3 years regarding RFA for BE.

RECENT FINDINGS

Our use of this technology has simultaneously gone too far, in that many patients who may not derive a benefit from these treatments are receiving them, and not far enough, in that many patients who would be eligible for ablative therapy never undergo screening exams to assess them for dysplastic BE, or do not have endoscopic therapy considered part of the treatment of superficial invasive cancer. Research to better identify patients with BE, risk stratify those patients, improve the quality of RFA treatment, and inform surveillance practices has the potential to optimize the benefit of RFA, and minimize the harms, costs, and risks.

Volumetric laser endomicroscopy in Barrett's esophagus: ready for primetime

Barrett's esophagus (BE) is the condition where intestinal metaplastic changes are found in the normal stratified squamous epithelium of the esophagus predisposing an individual to dysplasia and esophageal adenocarcinoma (EAC). It tends to affect males and is often the result of chronic gastroesophageal reflux disease (GERD). The current standard of therapy for diagnosing Barrett's is white light endoscopy (WLE) with biopsies obtained using the Seattle protocol. Multiple newer advanced modalities have been developed to improve diagnostic abilities, including volumetric laser endomicroscopy (VLE). This technique utilizes second generation optical coherence tomography (OCT) to provide an enhanced circumferential image to a depth of 3 mm with the potential for improved diagnostic yield for dysplasia, particularly submucosal lesions or lesions not seen by WLE. It has also been evaluated in guiding mapping of endotherapy as well as post therapy surveillance for recurrence. Although the results have been promising when used with current diagnostic standards, overall data are limited to support the routine use of VLE.

AGA Clinical Practice Update on Endoscopic Treatment of Barrett's Esophagus With Dysplasia and/or Early Cancer: Expert Review

DESCRIPTION

The purpose of this best practice advice article is to describe the role of Barrett's endoscopic therapy (BET) in patients with Barrett's esophagus (BE) with dysplasia and/or early cancer and appropriate follow-up of these patients.

METHODS

The best practice advice provided in this document is based on evidence and relevant publications reviewed by the committee. BEST PRACTICE ADVICE 1: In BE patients with confirmed low-grade dysplasia, a repeat examination with high-definition white-light endoscopy should be performed within 3-6 months to rule out the presence of a visible lesion, which should prompt endoscopic resection. BEST PRACTICE ADVICE 2: Both BET and continued surveillance are reasonable options for the management of BE patients with confirmed and persistent low-grade dysplasia. BEST PRACTICE ADVICE 3: BET is the preferred treatment for BE patients with high-grade dysplasia (HGD). BEST PRACTICE ADVICE 4: BET should be preferred over esophagectomy for BE patients with intramucosal esophageal adenocarcinoma (T1a). BEST PRACTICE ADVICE 5: BET is a reasonable alternative to esophagectomy in patients with submucosal esophageal adenocarcinoma (T1b) with low-risk features (<500-μm invasion in the submucosa [sm1], good to moderate differentiation, and no lymphatic invasion) especially in those who are poor surgical candidates. BEST PRACTICE ADVICE 6: In all patients undergoing BET, mucosal ablation should be applied to 1) all visible esophageal columnar mucosa; 2) 5-10 mm proximal to the squamocolumnar junction and 3) 5-10 mm distal to the gastroesophageal junction, as demarcated by the top of the gastric folds (ie, gastric cardia) using focal ablation in a circumferential fashion. BEST PRACTICE ADVICE 7: Mucosal ablation therapy should only be performed in the presence of flat BE without signs of inflammation and in the absence of visible abnormalities. BEST PRACTICE ADVICE 8: BET should be performed by experts in high-volume centers that perform a minimum of 10 new cases annually. BEST PRACTICE ADVICE 9: BET should be continued until there is an absence of columnar epithelium in the tubular esophagus on high-definition white-light endoscopy and preferably optical chromoendoscopy. In case of complete endoscopic eradication, the neosquamous mucosa and the gastric cardia are sampled by 4-quadrant biopsies. BEST PRACTICE ADVICE 10: If random biopsies obtained from the neosquamous epithelium demonstrate intestinal metaplasia/dysplasia or subsquamous intestinal metaplasia, a repeat endoscopy should be performed and visible islands or tongues should undergo targeted focal ablation. BEST PRACTICE ADVICE 11: Intestinal metaplasia of the gastric cardia (without residual columnar epithelium in the tubular esophagus) should not warrant additional ablation therapy. BEST PRACTICE ADVICE 12: When consenting patients for BET, the most common complication of therapy to be quoted is post-procedural stricture formation, occurring in about 6% of cases. Bleeding and perforation occur at rates <1%. BEST PRACTICE ADVICE 13: After complete eradication (endoscopic and histologic) of intestinal metaplasia has been achieved with BET, surveillance endoscopy with biopsies should be performed at the following intervals: for baseline diagnosis of HGD/esophageal adenocarcinoma: at 3, 6, and 12 months and annually thereafter; and baseline diagnosis of low-grade dysplasia: at 1 and 3 years. BEST PRACTICE ADVICE 14: Endoscopic surveillance post therapy should be performed with high-definition white-light endoscopy, including careful inspection of the neosquamous mucosal and retroflexed inspection of the gastric cardia. BEST PRACTICE ADVICE 15: The approach to recurrent disease is similar to that of the initial therapy; visible recurrent nodular lesions require endoscopic resection, whereas flat areas of columnar mucosa in the tubular esophagus can be treated with mucosal ablation. BEST PRACTICE ADVICE 16: Patients should be counseled on cancer risk in the absence of BET, as well as after BET, to allow for informed decision-making between the patient and the physician.

Prevalence and Incidence of Intestinal Metaplasia and Dysplasia of Gastric Cardia in Patients With Barrett's Esophagus After Endoscopic Therapy

BACKGROUND & AIMS

Endoscopic eradication therapy (EET) for Barrett's esophagus (BE) has unclear effects on the gastric cardia. We investigated the prevalence of intestinal metaplasia (IM) and dysplasia in the cardia after complete eradication of IM (CEIM) and the incidence of newly diagnosed cardia IM or dysplasia after EET.

METHODS

We performed a prospective study, from 2013 through 2016, of patients with previously successful EET undergoing surveillance after CEIM (cross-sectional group) and treatment-naïve patients with BE undergoing EET (longitudinal group). Standard biopsies were collected from multiple levels in the cardia and analyzed histologically. We calculated the prevalence (cross-sectional group) and the incidence (longitudinal group) of cardia IM or dysplasia after EET.

RESULTS

Of the 116 patients in the cross-sectional group, 17 (15%) had cardia IM or dysplasia after CEIM: 12 patients had IM, 2 patients were indefinite for dysplasia, and 3 patients had low-grade dysplasia. Cardia IM or dysplasia were most commonly found at the tops of gastric folds. Among 42 subjects in the longitudinal group, the pre-treatment prevalence of cardia IM or dysplasia was 28.5% (3 with non-dysplastic IM, 9 with dysplastic IM, 1 indefinite for dysplasia, 2 with low-grade dysplasia, 3 with high-grade dysplasia, and 3 with intramucosal cancer). All achieved CEIM. The incidence of cardia IM or dysplasia was 11.9% after 18 months of follow up. IM or dysplasia was more higher in the cardia after CEIM than in the tubular esophagus (P < .01).

CONCLUSIONS

In a prospective study, we found that cardia dysplasia becomes less, not more, common, after successful EET; recurrence of IM or dysplasia was more frequent in the cardia than the esophagus. Patients with BE undergoing EET should have careful examination of the cardia, with a single set of surveillance biopsies at the top of the gastric folds.

ENDOSCOPIC TREATMENT OF ESOPHAGEAL NEOPLASIA: A DECADE OF EVOLUTION

Traditional therapy for early esophageal neoplasia has been esophagectomy. In the past decade, the approach to these conditions has rapidly evolved, such that endoscopic therapy has become the primary modality to treat patients with esophageal dysplasia and superficial carcinoma. A variety of modalities are available, including thermal methods, such as radiofrequency ablation and argon plasma coagulation; cryotherapy, including spray liquid nitrogen cryotherapy and balloon-based nitrous oxide cryotherapy; and tissue resection methods, such as endoscopic mucosal resection and endoscopic submucosal dissection. Level 1 evidence substantiates that patients treated with these therapies have a low risk of developing invasive cancer. These treatments demonstrate an excellent safety profile. Future work in this area will define the best modalities of treatment, assess the utility of endoscopic therapy in combination with radiation therapy and chemotherapy, and improve current screening regimens to allow earlier detection of neoplasia.

Volumetric laser endomicroscopy features of dysplasia at the gastric cardia in Barrett's oesophagus: results from an observational cohort study

Objective

Volumetric laser endomicroscopy (VLE) is an advanced imaging modality used in Barrett’s oesophagus (BE) to help identify dysplasia in the oesophagus. VLE criteria exist for oesophageal dysplasia but not for dysplasia in the gastric cardia. The aim of this study was to determine if there are in vivo VLE features that can predict gastric cardia dysplasia in BE.

Design

This was a single-centre observational cohort study from August 2016 to August 2018. Patients were included if they had BE, were undergoing a VLE exam as standard of care, and had a suspicious target laser marked at the gastric cardia. The following VLE features were correlated to histology to determine if an association existed between histology subtype and VLE feature: wide crypts, irregular surface, one large isolated gland, multiple glands, and complex glands.

Results

A total of 110 in vivo gastric cardia targets in 77 patients with BE were analysed. The following abnormalities were identified: 61 wide crypts, 34 isolated glands, 16 irregular surfaces, 15 multiple glands, and 11 complex glands. Complex glands were the only VLE feature that correlated to any histology subtype. They were present in 71% of targets with high-grade dysplasia (HGD), T1a cancer or T1b cancer and had a sensitivity, specificity, and accuracy of 71%, 99%, and 85%, respectively. Of the 10 patients with complex glands on VLE and HGD/cancer on histology, 4 had a normal-appearing mucosa (40%) on endoscopy.

Conclusion

Identification of complex glands on VLE may aid in detection of HGD or early cancer in the gastric cardia in BE. This is particularly important, as dysplasia at the gastric cardia can be difficult to see endoscopically.

Anatomic location of Barrett's esophagus recurrence after endoscopic eradication therapy: development of a simplified surveillance biopsy strategy

BACKGROUND AND AIMS

Surveillance endoscopy is recommended after endoscopic eradication therapy (EET) for Barrett's esophagus (BE) because of the risk of recurrence. Currently recommended biopsy protocols are based on expert opinion and consist of sampling visible lesions followed by random 4-quadrant biopsy sampling throughout the length of the original BE segment. Despite this protocol, some recurrences are not visibly identified. We aimed to identify the anatomic location and histology of recurrences after successful EET with the goal of developing a more efficient and evidence-based surveillance biopsy protocol.

METHODS

We performed an analysis of a large multicenter database of 443 patients who underwent EET and achieved complete eradication of intestinal metaplasia (CE-IM) from 2005 to 2015. The endoscopic location of recurrence relative to the squamocolumnar junction (SCJ), visible recurrence identified during surveillance endoscopy, and time to recurrence after CE-IM were assessed.

RESULTS

Fifty patients with BE recurrence were studied in the final analysis. Seventeen patients (34%) had nonvisible recurrences. In this group, biopsy specimens demonstrating recurrence were taken from within 2 cm of the SCJ in 16 of these 17 patients (94%). Overall, 49 of 50 recurrences (98%) occurred either within 2 cm of the SCJ or at the site of a visible lesion. Late recurrences (>1 year) were more likely to be visible than early (<1 year) recurrences (P = .006).

CONCLUSIONS

Recurrence after EET detected by random biopsy sampling is identified predominately in the distal esophagus and occurs earlier than visible recurrences. As such, we suggest a modified biopsy protocol with targeted sampling of visible lesions followed by random biopsy sampling within 2 cm of the SCJ to optimize detection of recurrence after EET. (Clinical trial registration number: NCT02634645.).

Pathogenesis and Cells of Origin of Barrett's Esophagus

In patients with Barrett's esophagus (BE), metaplastic columnar mucosa containing epithelial cells with gastric and intestinal features replaces esophageal squamous mucosa damaged by gastroesophageal reflux disease. This condition is estimated to affect 5.6% of adults in the United States, and is a major risk factor for esophageal adenocarcinoma. Despite the prevalence and importance of BE, its pathogenesis is incompletely understood and there are disagreements over the cells of origin. We review mechanisms of BE pathogenesis, including transdifferentiation and transcommitment, and discuss potential cells of origin, including basal cells of the squamous epithelium, cells of esophageal submucosal glands and their ducts, cells of the proximal stomach, and specialized populations of cells at the esophagogastric junction (residual embryonic cells and transitional basal cells). We discuss the concept of metaplasia as a wound-healing response, and how cardiac mucosa might be the precursor of the intestinal metaplasia of BE. Finally, we discuss shortcomings in current diagnostic criteria for BE that have important clinical implications.

Timeline and location of recurrence following successful ablation in Barrett's oesophagus: an international multicentre study

OBJECTIVE

Surveillance interval protocols after complete remission of intestinal metaplasia (CRIM) post radiofrequency ablation (RFA) in Barrett's oesophagus (BE) are currently empiric and not based on substantial evidence. We aimed to assess the timeline, location and patterns of recurrence following CRIM to inform these guidelines.

DESIGN

Data on patients undergoing RFA for BE were obtained from prospectively maintained databases of five (three USA and two UK) tertiary referral centres. RFA was performed until CRIM was confirmed on two consecutive endoscopies.

RESULTS

594 patients achieved CRIM as of 1 May 2017. 151 subjects developed recurrent BE over a median (IQR) follow-up of 2.8 (1.4-4.4) years. There was 19% cumulative recurrence risk of any BE within 2 years and an additional 49% risk over the next 8.6 years. There was no evidence of a clinically meaningful change in the recurrence hazard rate of any BE, dysplastic BE or high-grade dysplasia/cancer over the duration of follow-up, with an estimated 2% (95% CI -7% to 12%) change in recurrence rate of any BE in a doubling of follow-up time. 74% of BE recurrences developed at the gastro-oesophageal junction (GOJ) (24.1% were dysplastic) and 26% in the tubular oesophagus. The yield of random biopsies from the tubular oesophagus, in the absence of visible lesions, was 1% (BE) and 0.2% (dysplasia).

CONCLUSIONS

BE recurrence risk following CRIM remained constant over time, suggesting that lengthening of follow-up intervals, at least in the first 5 years after CRIM, may not be advisable. Sampling the GOJ is critical to detecting recurrence. The requirement for random biopsies of the neosquamous epithelium in the absence of visible lesions may need to be re-evaluated.

Management of Barrett Esophagus Following Radiofrequency Ablation

Radiofrequency ablation (RFA) effectively treats dysplastic Barrett esophagus (BE), reduces the risk of esophageal adenocarcinoma (EAC), and infrequently produces complications. Complications of RFA include chest discomfort, esophageal stricturing, and bleeding. However, chest discomfort is usually transient and mild, strictures are generally amenable to dilation, and clinically significant bleeding is rare. Following RFA, intestinal metaplasia recurs at a rate of approximately 10% per patient year of follow-up time. Postablation dysplastic BE and EAC are rare. Moreover, recurrent disease is generally responsive to further endoscopic therapy and is associated with a benign clinical course. Although RFA is effective at producing low rates of postablation EAC and dysplastic recurrence, data suggest that current consensus guidelines for postablation surveillance are overly aggressive, as they mirror those for treatment-naive cohorts. Future guidelines may attenuate surveillance intervals, reducing the burden of endoscopic surveillance while providing for adequate detection of recurrent disease. Additional studies are needed to determine the length of time patients should ultimately remain in surveillance programs. Uncertainty exists regarding the appropriate application of chemopreventive measures (including proton pump inhibitors, aspirin, and statins) and novel imaging and sampling modalities (such as optical coherence tomography and wide-area transepithelial sampling) to reduce the risk of recurrent disease and sampling error, respectively. These uncertainties represent targets for future investigations.

Challenges in Endoscopic Therapy of Dysplastic Barrett's Esophagus

PURPOSE OF REVIEW

Barrett's esophagus (BE) is the only known measurable factor associated with esophageal adenocarcinoma. The development of endoscopic eradication therapy (EET) has transformed the way BE is managed. Given the fairly recent development of EET, its role in BE is still evolving.

RECENT FINDINGS

This paper discusses the challenges that endoscopists face at the preprocedural, intraprocedural, and postprocedural stages of BE management. These include challenges in risk stratification, dysplasia detection, ablation methods and dosimetry, choice of resection technique, and management of refractory disease. Despite the advances in EET in BE, there remain challenges that this review focuses on. Future research into these challenges will optimize ablation techniques and strategies in the future.

Acidic Bile Salts Induce Epithelial to Mesenchymal Transition via VEGF Signaling in Non-Neoplastic Barrett's Cells

BACKGROUND & AIMS

Metaplastic glands buried under squamous epithelium are frequently detected in patients with Barrett esophagus (BE). This subsquamous intestinal metaplasia might be responsible for cancers that develop despite endoscopic surveillance and for metaplasia recurrences after endoscopic ablation. To determine whether reflux induces BE cells to undergo an epithelial-to-mesenchymal transition (EMT) that produces subsquamous intestinal metaplasia, we assessed EMT in BE cells exposed to acidic bile salts and in rat and human esophageal tissues.

METHODS

We compared markers of EMT and cell motility in trans-well and 3-dimensional organotypic culture systems among dysplastic BE epithelial cell lines, nondysplastic telomerase-immortalized BE cell lines (BAR-T), and BAR-T cells exposed acutely or for 20 weeks to acidic bile salts. Vascular endothelial growth factor (VEGF) A was inhibited with a neutralizing antibody or CRISPR-Cas9n and VEGF receptor 2 was inhibited with SU1498 or shRNA, and cells were analyzed by immunohistochemistry, quantitative polymerase chain reaction, or immunoblotting for markers of VEGF signaling and EMT; cell motility was assessed by trans-well assay. We used immunohistochemistry and quantitative polymerase chain reaction to assess EMT markers in the columnar-lined esophagus of rats with surgically induced reflux esophagitis and in esophagectomy specimens from patients with BE.

RESULTS

We detected features of EMT (decreased cadherin 1 [CDH1]; increased fibronectin 1, vimentin, and matrix metalloproteinase 2; and increased motility) in dysplastic BE epithelial cell lines and in BAR-T cells exposed for 20 weeks, but not in unexposed BAR-T cells. Acute acidic bile salt exposure induced expression of zinc finger E-box binding homeobox 1 and 2 (ZEB1/2) in BAR-T cells, which decreased their expression of CDH1 and increased motility; inhibitors of VEGF signaling blocked these effects. Columnar-lined esophagus of rats with reflux esophagitis had increased expression of ZEB1/2 and decreased expression of CDH1 compared with controls. Dysplastic BE tissues also had significantly increased levels of ZEB1 and significantly decreased levels of CDH1 compared with nondysplastic BE tissues.

CONCLUSIONS

In BE cell lines, acidic bile salts induce EMT by VEGF signaling, which increases expression of ZEB1/2, repressors of CDH1. These observations suggest that reflux induces EMT in metaplastic BE tissues, which promotes development of subsquamous intestinal metaplasia.

Factors Associated With Recurrence of Barrett's Esophagus After Radiofrequency Ablation

BACKGROUND & AIMS

Radiofrequency ablation (RFA) is effective treatment for Barrett's esophagus (BE). However, some patients have recurrence after complete eradication of intestinal metaplasia (CEIM). We investigated the incidence of and factors associated with BE recurrence, with or without neoplasia, after RFA and CEIM using data from the national Veterans Affairs (VA) healthcare system.

METHODS

We performed a retrospective cohort study of Veterans with BE treated by RFA from 2005 through 2016 with follow-up endoscopy. Subjects were followed until BE recurrence, neoplasia, death until October 2016. CEIM, BE recurrence, and factors associated with recurrence were identified by review of medical records. We calculated incidence rates of BE recurrence, with and without neoplasia, after CEIM and identified predictors using Cox proportional hazards models.

RESULTS

We identified 430 Veterans with BE who were treated with RFA; of these 337 achieved CEIM (78.4%). Most were men (98.6%), White (83.7%), and 66.0% had baseline dysplasia. Of those with CEIM, 98 patients (29.1%) had recurrence of BE during a total 906.0 patient-years of follow-up (median 1.9 years) after CEIM (incidence, 10.8%/patient-year). Dysplasia developed in 20 patients (2.2%/patient-year) and cancer in 3 patients (0.3%/patient-year). Baseline dysplasia (hazard ratio [HR], 1.71; 95% CI, 1.03-2.84) and long-segment BE (HR, 1.59; 95% CI, 1.01-2.51) increased risk of BE recurrence whereas treatment at high-volume RFA facilities reduced risk of BE recurrence (for quartile 4 vs quartile 1: HR, 0.19; 95% CI, 0.05-0.68).

CONCLUSIONS

In a nationwide VA system study of outcomes of RFA for BE, we associated baseline dysplasia, long-segment BE, and treatment at low-volume RFA centers with recurrence of BE after CEIM. The findings call for performing these procedures in high-volume centers.

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.

Endoscopic management of dysplasia and early oesophageal cancer

In the past decade there have been technological advances in Endoscopic Eradication Therapy (EET) for the management of patients with oesophageal neoplasia and early cancer. Multiple endoscopic techniques now exist for both squamous and Barrett's oesophagus associated neoplasia or early cancer. A fundamental aspect of endotherapy is removal of the target lesion by endoscopic mucosal resection, or endosopic submucosal dissection. Residual tissue is subsequently ablated to remove the risk of recurrence. The most validated technique for Barrett's oesophagus is radiofrequency ablation, but other techniques such as hybrid-APC and cryotherapy also show good results. This chapter will discuss the evolution of EET, and which patients are most likely to benefit. It will also explore the evidence behind the success of different techniques and provide practical advice on how to carry out the endoscopic techniques with a focus on radiofrequency ablation and endoscopic mucosal resection in particular.

Development of Evidence-Based Surveillance Intervals After Radiofrequency Ablation of Barrett's Esophagus

BACKGROUND & AIMS

Barrett's esophagus (BE) recurs in 25% or more of patients treated successfully with radiofrequency ablation (RFA), so surveillance endoscopy is recommended after complete eradication of intestinal metaplasia (CEIM). The frequency of surveillance is informed only by expert opinion. We aimed to model the incidence of neoplastic recurrence, validate the model in an independent cohort, and propose evidence-based surveillance intervals.

METHODS

We collected data from the United States Radiofrequency Ablation Registry (US RFA, 2004-2013) and the United Kingdom National Halo Registry (UK NHR, 2007-2015) to build and validate models to predict the incidence of neoplasia recurrence after initially successful RFA. We developed 3 categories of risk and modeled intervals to yield 0.1% risk of recurrence with invasive adenocarcinoma. We fit Cox proportional hazards models assessing discrimination by C statistic and 95% confidence limits.

RESULTS

The incidence of neoplastic recurrence was associated with most severe histologic grade before CEIM, age, endoscopic mucosal resection, sex, and baseline BE segment length. In multivariate analysis, a model based solely on most severe pre-CEIM histology predicted neoplastic recurrence with a C statistic of 0.892 (95% confidence limit, 0.863-0.921) in the US RFA registry. This model also performed well when we used data from the UK NHR. Our model divided patients into 3 risk groups based on baseline histologic grade: non-dysplastic BE; indefinite for dysplasia, low-grade dysplasia, and high-grade dysplasia; or intramucosal adenocarcinoma. For patients with low-grade dysplasia, we propose surveillance endoscopy at 1 and 3 years after CEIM; for patients with high-grade dysplasia or intramucosal adenocarcinoma, we propose surveillance endoscopy at 0.25, 0.5, and 1 year after CEIM, then annually.

CONCLUSION

In analyses of data from the US RFA and UK NHR for BE, a much-attenuated schedule of surveillance endoscopy would provide protection from invasive adenocarcinoma. Adherence to the recommended surveillance intervals could decrease the number of endoscopies performed yet identify unresectable cancers at rates less than 1/1000 endoscopies.

Natural History of the Post-ablation Esophagus

Endoscopic ablative therapy including radiofrequency ablation (RFA) represents the preferred management strategy for dysplastic Barrett's esophagus (BE) and appears to diminish the risk of developing esophageal adenocarcinoma (EAC). Limited data describe the natural history of the post-ablation esophagus. Recent findings demonstrate that recurrent intestinal metaplasia (IM) following RFA is relatively frequent. However, dysplastic BE and EAC subsequent to the complete eradication of intestinal metaplasia (CEIM) are uncommon. Moreover, data suggest that the risk of recurrent disease is probably highest in the first year following CEIM. Recurrent IM and dysplasia are usually successfully eradicated with repeat RFA. Future studies may refine surveillance intervals and inform the length of time surveillance should be conducted following RFA with CEIM. Further data will also be necessary to understand the utility of chemopreventive strategies, including NSAIDs, in reducing the risk of recurrent disease.

Chemoprevention of Barrett's Esophagus and Esophageal Adenocarcinoma

Barrett's esophagus is common in Western countries, but progression to esophageal adenocarcinoma is uncommon. Chemoprevention therefore needs to consider whether benefits outweigh risks given an otherwise healthy population. This will depend on the particular population at risk and the relative safety of a potential preventive agent. Most evidence regarding the potential benefit of chemoprevention of Barrett's esophagus and prevention of progression to esophageal adenocarcinoma is based on observational studies such as case-control and cohort studies. Given the potential benefits and relatively low risks, patients with BE should receive once-daily PPI therapy, but routine use of twice-daily PPI is not recommended unless necessitated by poor control of reflux symptoms or esophagitis. Recent data suggest that the inverse associations between aspirin/NSAID use and esophageal adenocarcinoma may be the result of reducing neoplastic progression (from metaplasia to dysplasia and carcinoma) rather than initiation of Barrett's esophagus. While substantial associative data suggest a potential benefit of aspirin and nonaspirin NSAIDs in reducing the risk of progression of Barrett's esophagus, the low risk of progression and the potential risks (gastrointestinal bleeding, complicated ulcer disease, hemorrhagic stroke) do not warrant routine use, unless dictated by cardiovascular risk. Chemoprevention after mucosal ablation in those at highest risk of post-ablation recurrence (dysplastic Barrett's) is currently under investigation.

Higher Rate of Barrett's Detection in the First Year After Successful Endoscopic Therapy: Meta-analysis

BACKGROUND

Endoscopic eradication therapy (EET) is highly effective in treating dysplastic Barrett's esophagus (BE). Current surveillance intervals after complete remission of intestinal metaplasia (CRIM) are based on expert opinion. We performed a meta-analysis to compare BE detection in the first year to the subsequent ones METHODS: We searched MEDLINE, EMBASE, Scopus and Cochrane Central Register of Controlled Trials through 1 August 2017 for studies reporting IM and neoplasia detection after CRIM. Pooled incidence rate (IR) of IM detection was calculated for each year after CRIM. We compared IM, dysplasia, and high grade dysplasia (HGD)/esophageal adenocarcinoma (EAC) detection in the first year after CRIM to the years after.

RESULTS

Twenty two studies were included involving 1973 patients with follow-up of 5176 patient-years. IM detection IR per patient-year in the 1st year was 12% (95% CI: 8-17%), in the 2nd year 7% (95% CI: 4-11%), and in the 3rd year 3% (95% CI: 1-7%). IM detection rate in the first year was significantly higher compared to the years after (relative risk (RR) 1.8 (95% CI: 1.29-2.49)). Dysplasia detection IR in the first year after achieving CRIM was 3% per patient-year (95% CI: 2-5%). Dysplasia detection IR after the first year was 1% (95% CI: 1-2%) and significantly higher in the first year compared to the years after (RR: 1.92 (95% CI: 1.32-2.8). HGD/EAC detection was 1 %/patient-year (95% CI: 0-2%) in the first year after CRIM compared to 0%/patient-year (95% CI: 0-1%) in subsequent years. HGD/EAC IR was higher in the first year (RR: 1.58 (95% CI: 0.94-2.65)).

CONCLUSION

Neoplasia detection after successful treatment of BE appears more common within the first year of surveillance. This appears to be due to incompletely treated prevalent rather than recurrent disease. More intensive surveillance in the first year following CRIM is warranted.

Update on the management of Barrett's esophagus in Austria

Background

Barrett’s esophagus (BE) is the premalignant manifestation of gastroesophageal reflux disease (GERD). Radiofrequency ablation (RFA) with and without endoscopic resection (ER) is a novel treatment for BE.

Methods

Here we present a single-center update of the recommendations of a recent (June 2015) interdisciplinary expert panel meeting on the management of BE with dysplasia as well as cancer-positive and cancer-negative BE. We conducted a PubMed search of studies published in 2016 and 2017 on the topic of BE and RFA.

Results

Our update reconfirms that BE positive for T1a cancer as well as low- and high-grade dysplasia justifies the use of RFA ± ER, offering an 80–100% rate of BE clearance. RFA ± ER of dysplastic BE is tenfold more effective for cancer prevention when compared with surveillance. Risk factors for recurrence and follow-up treatments include baseline histopathology (dysplasia/T1a cancer), esophagitis, hiatal hernia >3 cm, smoking habits, BE segments >3 cm, and >10 years of GERD symptoms. A baseline diagnosis for dysplasia and T1a cancer should include a second expert pathologist opinion. Recent data justify the use of RFA for nondysplastic BE only in controlled clinical trials. Antireflux surgery can be offered to those with function-test-proven, GERD-symptom-positive BE before, during, or after RFA ± ER. Additionally, there is growing evidence that the intake of a sugar-rich diet is positively correlated with the development of GERD, BE, and cancer.

Conclusion

RFA ± ER should be offered for dysplastic BE and T1a cancer after ER as well as for nondysplastic BE with additional risk factors in controlled trials. Antireflux surgery can be offered to patients with function-test-proven GERD-symptom-positive BE. Diet considerations should be included in the management of GERD and BE.

Endoscopic mucosal ablation and resection of Barrett's esophagus and related diseases

The prevalence of gastroesophageal reflux disease as well as the incidence of Barrett's esophagus (BE) has increased in the Western world over the last decades. The chronic reflux of gastric secretions injuries the esophageal mucosa and triggers cellular and molecular changes inducing the transformation of the normal squamous mucosa into columnar metaplastic epithelium. BE is a premalignant condition that can progress to low-grade dysplasia, high-grade dysplasia and ultimately esophageal adenocarcinoma. An early diagnosis of dysplastic changes and the adoption of appropriate therapeutic approaches are essential to improve patient outcomes and survival. Endoscopic therapies such as radiofrequency ablation (RFA) and endoscopic mucosal resection (EMR) have been developed to treat dysplastic changes and mucosal abnormalities suspicious of malignancy. RFA has shown to be safe and effective for the treatment of low and high-grade dysplasia. EMR is diagnostic for mucosal lesions and potentially therapeutic for high-grade dysplasia or intramucosal adenocarcinoma. Proficient endoscopic skills and frequent practice are essential elements for a successful result. Here, we describe patient selection, the pre- and post-operative management, and the surgical technique for RFA and EMR in patients with the diagnosis of dysplastic BE and intramucosal esophageal adenocarcinoma.

Metaplasia: tissue injury adaptation and a precursor to the dysplasia-cancer sequence

Metaplasia is the replacement of one differentiated somatic cell type with another differentiated somatic cell type in the same tissue. Typically, metaplasia is triggered by environmental stimuli, which may act in concert with the deleterious effects of microorganisms and inflammation. The cell of origin for intestinal metaplasia in the oesophagus and stomach and for pancreatic acinar-ductal metaplasia has been posited through genetic mouse models and lineage tracing but has not been identified in other types of metaplasia, such as squamous metaplasia. A hallmark of metaplasia is a change in cellular identity, and this process can be regulated by transcription factors that initiate and/or maintain cellular identity, perhaps in concert with epigenetic reprogramming. Universally, metaplasia is a precursor to low-grade dysplasia, which can culminate in high-grade dysplasia and carcinoma. Improved clinical screening for and surveillance of metaplasia might lead to better prevention or early detection of dysplasia and cancer.

Late Recurrence of Barrett's Esophagus After Complete Eradication of Intestinal Metaplasia is Rare: Final Report From Ablation in Intestinal Metaplasia Containing Dysplasia Trial

BACKGROUND & AIMS

The goal of treatment for Barrett's esophagus (BE) with dysplasia is complete eradication of intestinal metaplasia (CEIM). The long-term durability of CEIM has not been well characterized, so the frequency and duration of surveillance are unclear. We report results from a 5-year follow-up analysis of patients with BE and dysplasia treated by radiofrequency ablation (RFA) in the randomized controlled Ablation of Intestinal Metaplasia Containing Dysplasia (AIM) trial.

METHODS

Participants for the AIM Dysplasia trial (18-80 years old) were recruited from 19 sites in the United States and had endoscopic evidence of non-nodular dysplastic BE ≤8 cm in length. Subjects (n = 127) were randomly assigned (2:1 ratio) to receive either RFA (entire BE segment ablated circumferentially) or a sham endoscopic procedure; patients in the sham group were offered RFA treatment 1 year later, and all patients were followed for 5 years. We collected data on BE recurrence (defined as intestinal metaplasia in the tubular esophagus) and dysplastic BE recurrence among patients who achieved CEIM. We constructed Kaplan-Meier estimates and applied parametric survival analysis to examine proportions of patients without any recurrence and without dysplastic recurrence.

RESULTS

Of 127 patients in the AIM Dysplasia trial, 119 received RFA and met inclusion criteria. Of those 119, 110 (92%) achieved CEIM. Over 401 person-years of follow-up (mean, 3.6 years per patient; range, 0.2-5.8 years), 35 of 110 (32%) patients had recurrence of BE or dysplasia, and 19 (17%) had dysplasia recurrence. The incidence rate of BE recurrence was 10.8 per 100 person-years overall (95% CI, 7.8-15.0); 8.3 per 100 person-years among patients with baseline low-grade dysplasia (95% CI, 4.9-14.0), and 13.5 per 100 person-years among patients with baseline high-grade dysplasia (95% CI 8.8-20.7). The incidence rate of dysplasia recurrence was 5.2 per 100 person-years overall (95% CI 3.3-8.2); 3.3 per 100 person-years among patients with baseline low-grade dysplasia (95% CI 1.5-7.2), and 7.3 per 100 person-years among patients with baseline high-grade dysplasia (95% CI 4.2-12.5). Neither BE nor dysplasia recurred at a constant rate. There was a greater probability of recurrence in the first year following CEIM than in the following 4 years combined.

CONCLUSIONS

In this analysis of prospective cohort data from the AIM Dysplasia trial, we found BE to recur after CEIM by RFA in almost one third of patients with baseline dysplastic disease; most recurrences occurred during the first year after CEIM. However, patients who achieved CEIM and remained BE free at 1 year after RFA had a low risk of BE recurrence. Studies are needed to determine when surveillance can be decreased or discontinued; our study did not identify any BE or dysplasia recurrence after 4 years of surveillance.

MicroRNA profile in neosquamous esophageal mucosa following ablation of Barrett's esophagus

AIM

To investigate the microRNA expression profile in esophageal neosquamous epithelium from patients who had undergone ablation of Barrett's esophagus.

METHODS

High throughput screening using TaqMan® Array Human MicroRNA quantitative PCR was used to determine expression levels of 754 microRNAs in distal esophageal mucosa (1 cm above the gastro-esophageal junction) from 16 patients who had undergone ablation of non-dysplastic Barrett's esophagus using argon plasma coagulation vs pretreatment mucosa, post-treatment proximal normal non-treated esophageal mucosa, and esophageal mucosal biopsies from 10 controls without Barrett's esophagus. Biopsies of squamous mucosa were also taken from 5 cm above the pre-ablation squamo-columnar junction. Predicted mRNA target pathway analysis was used to investigate the functional involvement of differentially expressed microRNAs.

RESULTS

Forty-four microRNAs were differentially expressed between control squamous mucosa vs post-ablation neosquamous mucosa. Nineteen microRNAs were differentially expressed between post-ablation neosquamous and post-ablation squamous mucosa obtained from the more proximal non-treated esophageal segment. Twelve microRNAs were differentially expressed in both neosquamous vs matched proximal squamous mucosa and neosquamous vs squamous mucosa from healthy patients. Nine microRNAs (miR-424-5p, miR-127-3p, miR-98-5p, miR-187-3p, miR-495-3p, miR-34c-5p, miR-223-5p, miR-539-5p, miR-376a-3p, miR-409-3p) were expressed at higher levels in post-ablation neosquamous mucosa than in matched proximal squamous and healthy squamous mucosa. These microRNAs were also more highly expressed in Barrett's esophagus mucosa than matched proximal squamous and squamous mucosa from controls. Target prediction and pathway analysis suggests that these microRNAs may be involved in the regulation of cell survival signalling pathways. Three microRNAs (miR-187-3p, miR-135b-5p and miR-31-5p) were expressed at higher levels in post-ablation neosquamous mucosa than in matched proximal squamous and healthy squamous mucosa. These miRNAs were expressed at similar levels in pre-ablation Barrett's esophagus mucosa, matched proximal squamous and squamous mucosa from controls. Target prediction and pathway analysis suggests that these microRNAs may be involved in regulating the expression of proteins that contribute to barrier function.

CONCLUSION

Neosquamous mucosa arising after ablation of Barrett's esophagus expresses microRNAs that may contribute to decreased barrier function and microRNAs that may be involved in the regulation of survival signaling pathways.

Recent Advances in Endoscopy

In this narrative review, invited by the Editors of Gastroenterology, we summarize recent advances in the field of gastrointestinal endoscopy. We have chosen articles published primarily in the past 2-3 years. Although a thorough literature review was performed for each topic, the nature of the article is subjective and systematic and is based on the authors' experience and expertise regarding articles we believed were most likely to be of high clinical and scientific importance.

Care of the Postablation Patient: Surveillance, Acid Suppression, and Treatment of Recurrence

Endoscopic eradication therapy is effective and durable for the treatment of Barrett's esophagus (BE), with low rates of recurrence of dysplasia but significant rates of recurrence of intestinal metaplasia. Identified risk factors for recurrence include age and length of BE before treatment and may also include presence of a large hiatal hernia, higher grade of dysplasia before treatment, and history of smoking. Current guidelines for surveillance following ablation are limited, with recommendations based on low-quality evidence and expert opinion. New modalities including optical coherence tomography and wide-area tissue sampling with computer-assisted analysis show promise as adjunctive surveillance modalities.

Radiofrequency Ablation of Barrett's Esophagus: Efficacy, Complications, and Durability

In the last decade, radiofrequency ablation in combination with endoscopic mucosal resection has simplified and improved the treatment of Barrett's esophagus. These treatments not only reduced the progression of dysplastic Barrett's esophagus to esophageal adenocarcinoma but also decreased treatment-related complications. More recent data from larger series with extended follow-up periods are emerging to refine expectations in patients treated with radiofrequency ablation. Although most patients achieve eradication of neoplasia and intestinal metaplasia, in the long-term a substantial portion of patients develop recurrent disease. This article provides an updated review of radiofrequency ablation efficacy, complications, and durability.

Esophagectomy for Superficial Esophageal Neoplasia

Endoscopic therapies have become the standard of care for most cases of Barrett's esophagus with high-grade dysplasia or intramucosal adenocarcinoma. Despite a rapid and dramatic evolution in treatment paradigms, esophagectomy continues to occupy a place in the therapeutic armamentarium for superficial esophageal neoplasia. The managing physician must remain cognizant of the limitations of endoscopic approaches and consider surgical resection when they are exceeded. Esophagectomy, performed at experienced centers for appropriately selected patients with early-stage disease can be undertaken with the expectation of cure as well as low mortality, acceptable morbidity, and good long-term quality of life.