Treatment for Barrett's oesophagus

ENDOSCOPIC ABLATION COMBINED WITH FUNDOPLICATION PLUS ACID SUPPRESSION-DUODENAL DIVERSION PROCEDURE FOR LONG SEGMENT BARRETT´S ESOPHAGUS: EARLY AND LONG-TERM OUTCOME

BACKGROUND:

The addition of endoscopic ablative therapy plus proton pump inhibitors or fundoplication is postulated for the treatment of patients with long-segment Barrett´s esophagus (LSBE); however, it does not avoid acid and bile reflux in these patients. Fundoplication with distal gastrectomy and Roux-en-Y gastrojejunostomy is proposed as an acid suppression-duodenal diversion procedure demonstrating excellent results at long-term follow-up. There are no reports on therapeutic strategy with this combination.

AIMS:

To determine the early and long-term results observed in LSBE patients with or without low-grade dysplasia who underwent the acid suppression-duodenal diversion procedure combined with endoscopic therapy.

METHODS:

Prospective study including patients with endoscopic LSBE using the Prague classification for circumferential and maximal lengths and confirmed by histological study. Patients were submitted to argon plasma coagulation (21) or radiofrequency ablation (31). After receiving treatment, they were monitored at early and late follow-up (5–12 years) with endoscopic and histologic evaluation.

RESULTS:

Few complications (ulcers or strictures) were observed after the procedure. Re-treatment was required in both groups of patients. The reduction in length of metaplastic epithelium was significantly better after radiofrequency ablation compared to argon plasma coagulation (10.95 vs 21.15 mms for circumferential length; and 30.96 vs 44.41 mms for maximal length). Intestinal metaplasia disappeared in a high percentage of patients, and histological long-term results were quite similar in both groups.

CONCLUSIONS:

Endoscopic procedures combined with fundoplication plus acid suppression with duodenal diversion technique to eliminate metaplastic epithelium of distal esophagus could be considered a good alternative option for LSBE treatment.

Biological welding - novel technique in the treatment of esophageal metaplasia

<b>Introduction:</b> Biological welding - controlled action of high frequency current on living tissues, which leads to their structural changes and weld formation - connection with unique biological properties (strength, high elasticity, insensitivity to microbial infection, stimulating effect on the regeneration process, speed and quality which surpasses the normal uncomplicated healing) [22]. This method is used in various fields of surgery, but at the moment there is no data on its use in case of esophageal cylindrocellular (intestinal) metaplasia (further esophageal metaplasia or Barrett's esophagus). <br><b>Objective:</b> The goal of this study is to evaluate biologic welding as a treatment option for patients with Barrett's esophagus. <br><b>Materials and methods:</b> Single-center retrospective review of patients with short-segment Barrett's esophagus and metaplasia were treated by argon plasma coagulation (APC) or Paton's welding. This was followed by Nissen fundoplication. Primary outcome of this study was mucosal healing with morphological confirmation of the absence of metaplasia. The groups included patients with a short segment of the esophagus Barrett's C2-3M3-4 (Prague Classification 2004) and high dysplasia without nodule formation in combination with hiatal hernia (VI World Congress of the International Society for Esophageal Diseases; ISED) [23-25]). <br><b>Results:</b> A total of 49 patients were included in the study with 25 patients treated by APC laser and 24 by biowelding. Four patients (16.0%) in the APC group developed stenosis and 5 patients (20.0%) developed recurrence compared to none in the biowelding group. Patients in the biowelding group had a significantly faster rate of mucosal healing leading to faster progression to Nissen fundoplication (at average 53 days) compared to APC laser group (surgery at 115 days). <br><b>Conclusions:</b> Biological welding of Paton's is a safe and effective treatment option for patients with esophageal metaplasia.

Antireflux surgery is required after endoscopic treatment for Barrett's esophagus

<b>Introduction:</b> Barrett's esophagus is an acquired condition that develops as a result of transformation of normal stratified squamous epithelium in the lower part of the esophagus into columnar epithelium. Barrett's esophagus is considered to be a complication of gastroesophageal reflux disease (GERD). Various endoscopic techniques have been shown to be successful in the treatment of this condition. However, long-term success in preventing further esophageal dysplasia is not clear. Biological welding consists in the application of controlled high-frequency current on living tissues and has been used to stop gastrointestinal bleeding, similarly to the APC technique which involves ablation of small intestinal metaplasia of the esophageal mucosa.<br/> <b>Aim:</b> The goal of this study was to evaluate the effectiveness of endoscopic techniques in the treatment of Barrett's esophagus and verify the need for a subsequent surgical intervention in patients with GERD complicated by Barrett's esophagus. <br/><b> Material and methods: </b> Patients with Barrett's esophagus C1-3M2-4 (Prague classification from 2004) and high dysplasia without nodules, as well as patients with confirmed GERD without hiatal hernia, were included in this study. Endoscopic treatment was performed with the use of argonoplasmic coagulation (APC) and high-frequency welding of living tissues (HFW). After the examination the patients were re-examined. Patients with recurrence of metaplasia and high DeMeester score (˃ 100) underwent antireflux surgery - crurography and Nissen fundoplication with creation of a soft and short cuff.<br/><b>Results:</b> A total of 89 patients were included in the study, 81 of whom were reexamined after ablation of Barrett's esophagus.In 12 patients, a recurrence of intestinal metaplasia resembling the small intestine was identified. Implementation of two-stage treatment was required for 9 patients - it involved a second procedure of ablation of the esophagus, followed by antireflux surgery. Surgical treatment was refused by 3 patients, who underwent only the second ablation procedure. All patients received drug therapy, consisting of prokinetics and proton pump inhibitors. Esophageal pH monitoring was repeated 3 months after surgery, showing normalization of the DeMeester score. As a result, the patients experienced no complaints such as heartburn, chest pain or dysphagia, which significantly improved their quality of life. Esophagogastroduodenoscopy and biopsy of the mucous membrane of the lower third of the esophagus were performed in accordance with the Seattle Protocol. After examining histological specimens, no regions of metaplasia were identified. <br/><b>Conclusion:</b> Antireflux surgery is required as a part of the treatment for Barrett's esophagus, which prevents further dysplasia and development of esophageal cancer.<br/&gt.

Molecular Profile of Barrett's Esophagus and Gastroesophageal Reflux Disease in the Development of Translational Physiological and Pharmacological Studies

Barrett's esophagus (BE) is a premalignant condition caused by gastroesophageal reflux disease (GERD), where physiological squamous epithelium is replaced by columnar epithelium. Several in vivo and in vitro BE models were developed with questionable translational relevance when implemented separately. Therefore, we aimed to screen Gene Expression Omnibus 2R (GEO2R) databases to establish whether clinical BE molecular profile was comparable with animal and optimized human esophageal squamous cell lines-based in vitro models. The GEO2R tool and selected databases were used to establish human BE molecular profile. BE-specific mRNAs in human esophageal cell lines (Het-1A and EPC2) were determined after one, three and/or six-day treatment with acidified medium (pH 5.0) and/or 50 and 100 µM bile mixture (BM). Wistar rats underwent microsurgical procedures to generate esophagogastroduodenal anastomosis (EGDA) leading to BE. BE-specific genes (keratin (KRT)1, KRT4, KRT5, KRT6A, KRT13, KRT14, KRT15, KRT16, KRT23, KRT24, KRT7, KRT8, KRT18, KRT20, trefoil factor (TFF)1, TFF2, TFF3, villin (VIL)1, mucin (MUC)2, MUC3A/B, MUC5B, MUC6 and MUC13) mRNA expression was assessed by real-time PCR. Pro/anti-inflammatory factors (interleukin (IL)-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12, IL-13, tumor necrosis factor α, interferon γ, granulocyte-macrophage colony-stimulating factor) serum concentration was assessed by a Luminex assay. Expression profile in vivo reflected about 45% of clinical BE with accompanied inflammatory response. Six-day treatment with 100 µM BM (pH 5.0) altered gene expression in vitro reflecting in 73% human BE profile and making this the most reliable in vitro tool taking into account two tested cell lines. Our optimized and established combined in vitro and in vivo BE models can improve further physiological and pharmacological studies testing pathomechanisms and novel therapeutic targets of this disorder.

Screening for esophageal adenocarcinoma and precancerous conditions (dysplasia and Barrett's esophagus) in patients with chronic gastroesophageal reflux disease with or without other risk factors: two systematic reviews and one overview of reviews to inform a guideline of the Canadian Task Force on Preventive Health Care (CTFPHC)

BACKGROUND

Two reviews and an overview were produced for the Canadian Task Force on Preventive Health Care guideline on screening for esophageal adenocarcinoma in patients with chronic gastroesophageal reflux disease (GERD) without alarm symptoms. The goal was to systematically review three key questions (KQs): (1) The effectiveness of screening for these conditions; (2) How adults with chronic GERD weigh the benefits and harms of screening, and what factors contribute to their preferences and decision to undergo screening; and (3) Treatment options for Barrett's esophagus (BE), dysplasia or stage 1 EAC (overview of reviews).

METHODS

Bibliographic databases (e.g. Ovid MEDLINE®) were searched for each review in October 2018. We also searched for unpublished literature (e.g. relevant websites). The liberal accelerated approach was used for title and abstract screening. Two reviewers independently screened full-text articles. Data extraction and risk of bias assessments were completed by one reviewer and verified by another reviewer (KQ1 and 2). Quality assessments were completed by two reviewers independently in duplicate (KQ3). Disagreements were resolved through discussion. We used various risk of bias tools suitable for study design. The GRADE framework was used for rating the certainty of the evidence.

RESULTS

Ten studies evaluated the effectiveness of screening. One retrospective study reported no difference in long-term survival (approximately 6 to 12 years) between those who had a prior esophagogastroduodenoscopy and those who had not (adjusted HR 0.93, 95% confidence interval (CI) 0.58-1.50). Though there may be higher odds of a stage 1 diagnosis than a more advanced diagnosis (stage 2-4) if an EGD had been performed in the previous 5 years (OR 2.27, 95% CI 1.00-7.67). Seven studies compared different screening modalities, and showed little difference between modalities. Three studies reported on patients' unwillingness to be screened (e.g. due to anxiety, fear of gagging). Eleven systematic reviews evaluated treatment modalities, providing some evidence of early treatment effect for some outcomes.

CONCLUSIONS

Little evidence exists on the effectiveness of screening and values and preferences to screening. Many treatment modalities have been evaluated, but studies are small. Overall, there is uncertainty in understanding the effectiveness of screening and early treatments.

SYSTEMATIC REVIEW REGISTRATIONS

PROSPERO (CRD42017049993 [KQ1], CRD42017050014 [KQ2], CRD42018084825 [KQ3]).

Economic evaluation of endoscopic radiofrequency ablation for the treatment of dysplastic Barrett's esophagus in Spain

BACKGROUND AND STUDY AIMS

To assess the cost-effectiveness of introducing endoscopic treatment based on radiofrequency ablation plus endoscopic mucosal resection in selected patients into the standard of care of Barrett's esophagus patients with high-grade dysplasia or low-grade dysplasia in Spain.

METHODS

The disease evolution was modeled via a semi-Markov model. The treatment strategies compared included endoscopic treatment based on radiofrequency ablation plus endoscopic mucosal resection and the Standard of Care (esophagectomy or palliative chemoradiotherapy according to disease status for high-grade dysplasia and endoscopic surveillance for low-grade dysplasia). Efficacy rates, transition probabilities and utility values were obtained from the literature. Clinical management patterns and resource use were modeled according to Spanish clinical expert opinion. Costs were expressed in euros (€) from 2016 reflecting the Spanish National Health System perspective. Sensitivity analyses were performed to assess the robustness of the model.

RESULTS

With respect to the Spanish Standard of Care, endoscopic treatment based on radiofrequency ablation plus endoscopic mucosal resection was a dominant strategy for high-grade dysplasia patients. When a willingness-to-pay threshold of €30,000 per quality-adjusted life-years gained was considered, this was cost-effective for low-grade dysplasia patients (€12,865 per quality-adjusted life-years gained). The sensitivity analyses supported the base case analysis results and pointed towards the main drivers of uncertainty in the model.

CONCLUSIONS

From a health care decision-maker, endoscopic treatment based on radiofrequency ablation plus endoscopic mucosal resection is the intervention of choice for dysplasic Barrett's esophagus patients in Spain.

Risk stratification for malignant progression in Barrett’s esophagus: Gender, age, duration and year of surveillance

AIM

To clarify risk based upon segment length, diagnostic histological findings, patient age and year of surveillance, duration of surveillance and gender.

METHODS

Patients registered with the United Kingdom Barrett’s Oesophagus Registry from 9 United Kingdom centers were included. The outcome measures were (1) development of all grades of dysplasia; (2) development of high-grade of dysplasia or adenocarcinoma; and (3) development of adenocarcinoma. Prevalent cases and subjects with < 1 year of follow-up were excluded. The covariates examined were segment length, previous biopsy findings, age at surveillance, duration of surveillance, year of surveillance and gender.

RESULTS

One thousand and one hundred thirty six patients were included (total 6474 patient-years). Fifty-four patients developed adenocarcinoma (0.83% per annum), 70 developed high-grade dysplasia/adenocarcinoma (1.1% per annum) and 190 developed any grade of dysplasia (3.5% per annum). High grade dysplasia and adenocarcinoma increased with age and duration of surveillance. The risk of low-grade dysplasia development was not dependent on age at surveillance. Segment length and previous biopsy findings were also significant factors for development of dysplasia and adenocarcinoma.

CONCLUSION

The risk of development of low-grade dysplasia is independent of age at surveillance, but high-grade dysplasia and adenocarcinoma were more commonly found at older age. Segment length and previous biopsy findings are also markers of risk. This study did not demonstrate stabilisation of the metaplastic segment with prolonged surveillance.

Yesterday and today of Barrett's esophagus: Historical evolution and research hotspots

It has been more than 60 years since the concept of Barrett's esophagus (BE) was put forward, and over these a few decades, we have made great progress in the diagnosis and treatment of BE. BE does not cause clinical symptoms, but it attracts wide attention, because it is an important precursor lesion of esophageal adenocarcinoma. The purpose of this article is to review the process of the recognition of BE and the current research hotspots as well as to discuss the current status of esophageal adenocarcinoma screening in BE patients. We aim to provide clinicians with an overview of the ins and outs of the disease, which will help them improve the diagnosis and treatment of BE in clinical practice and provide patients with beneficial treatment.

Update on management of Barrett's esophagus

Barrett's esophagus (BE) is a common condition that develops as a consequence of gastroesophageal reflux disease. The significance of Barrett's metaplasia is that predisposes to cancer development. This article provides a current evidence-based review for the management of BE and related early neoplasia. Controversial issues that impact the management of patients with BE, including definition, screening, clinical aspects, diagnosis, surveillance, and management of dysplasia and early cancer have been assessed.

Ablative Endoscopic Therapies for Barrett's-Esophagus-Related Neoplasia

Barrett's esophagus (BE) is more common in developed countries. Endoscopic therapy is an effective treatment method in management of dysplastic BE. Ablation by thermal energy, freezing, or photochemical injury completely eradicates dysplasia and specialized intestinal metaplasia resulting in neosquamation of esophagus. Among the ablative modalities, radiofrequency ablation (RFA) is the most studied with safe, effective, and durable long-term outcomes. Cryotherapy, argon plasma coagulation, and photodynamic therapy can be offered in select patients when RFA is unavailable, has failed, or is contraindicated. Future research on natural disease progression, biomarkers, advanced imaging, and application of endoscopic techniques will lead to better clinical outcomes for BE-associated neoplasia.

The tissue effect of argon-plasma coagulation with prior submucosal injection (Hybrid-APC) versus standard APC: A randomized ex-vivo study

BACKGROUND

Thermal ablation for Barrett's oesophagus has widely been established in gastrointestinal endoscopy during the last decade. The mainly used methods of radiofrequency ablation (RFA) and argon-plasma coagulation (APC) carry a relevant risk of stricture formation of up to 5-15%. Newer ablation techniques that are able to overcome this disadvantage would therefore be desirable. The aim of the present study was to compare the depth of tissue injury of the new method of Hybrid-APC versus standard APC within a randomized study in a porcine oesophagus model.

METHODS

Using a total of eight explanted pig oesophagi, 48 oesophageal areas were ablated either by standard or Hybrid-APC (APC with prior submucosal fluid injection) using power settings of 50 and 70 W. The depth of tissue injury to the oesophageal wall was analysed macroscopically and histopathologically.

RESULTS

Using 50 W, mean coagulation depth was 937 ± 469 µm during standard APC, and 477 ± 271 µm during Hybrid-APC (p = 0.064). Using 70 W, coagulation depth was 1096 ± 320 µm (standard APC) and 468 ± 136 µm (Hybrid-APC; p = 0.003). During all settings, damage to the muscularis mucosae was observed. Using standard APC, damage to the submucosal layer was observed in 4/6 (50 W) and 6/6 cases (70 W). During Hybrid-APC, coagulation of the submucosal layer occurred in 2/6 (50 W) and 1/6 cases (70 W). The proper muscle layer was only damaged during conventional APC (50 W: 1/6; 70 W: 3/6).

LIMITATIONS

Ex-vivo animal study with limited number of cases.

CONCLUSIONS

Hybrid-APC reduces coagulation depth by half in comparison with standard APC, with no thermal injury to the proper muscle layer. It may therefore lead to a lower rate of stricture formation during clinical application.

Barrett’s oesophagus: Evidence from the current meta-analyses

Guidelines have been published regarding the management of Barrett’s oesophagus (columnar-lined oesophagus). These have examined the role of surveillance in an effort to detect dysplasia and early cancer. The guidelines have provided criteria for enrolment into surveillance and some risk stratification with regard to surveillance interval. The research basis for the decisions reached with regard to cancer risk is weak and this manuscript has examined the available data published from meta-analyses up to 25^th April 2013 (much of which has been published since the guidelines and their most recent updates have been written). There were 9 meta-analyses comparing patients with Barrett’s oesophagus to control populations. These have demonstrated that Barrett’s oesophagus is more common in males than females, in subjects who have ever smoked, in subjects with obesity, in subjects with prolonged symptoms of gastro-oesophageal reflux disease, in subjects who do not have infection with Helicobacter pylori and in subjects with hiatus hernia. These findings should inform public health measures in reducing the risk of Barrett’s oesophagus and subsequent surveillance burden and cancer risk. There were 8 meta-analyses comparing different groups of patients with Barrett’s oesophagus with regard to cancer risk. These have demonstrated that there was no statistically significant benefit of antireflux surgery over medical therapy, that endoscopic ablative therapy was effective in reducing cancer risk that there was similar cancer risk in patients with Barrett’s oesophagus independent of geographic origin, that the adenocarcinoma incidence in males is twice the rate in females, that the cancer risk in long segment disease showed a trend to be higher than in short segment disease, that there was a trend for higher cancer risk in low-grade dysplasia over non-dysplastic Barrett’s oesophagus, that there is a lower risk in patients with Helicobacter pylori infection and that there is a significant protective effect of aspirin and statins. There were no meta-analyses examining the role of intestinal metaplasia. These results demonstrate that guidance regarding surveillance based on the presence of intestinal metaplasia, segment length and the presence of low-grade dysplasia has a weak basis, and further consideration should be given to gender and helicobacter status, ablation of the metaplastic segment as well as the chemoprotective role of aspirin and statins.

Endoscopic diagnosis of early Barrett's neoplasia: perspectives for advanced endoscopic technology

Barrett's esophagus (BE) is a metaplastic condition that occurs secondary to gastroesophageal reflux disease. BE is also a precursor to esophageal adenocarcinoma, which, although still rare in Japan, is one of the most rapidly increasing cancers in Western countries. However, the prevalence of gastroesophageal reflux disease has increased significantly over the past few decades in Japan, possibly leading to an incremental rise in BE and the associated inherent risk of adenocarcinoma. Given the poor prognosis of advanced-stage Barrett's adenocarcinoma, endoscopic surveillance is recommended for subjects with BE to detect early neoplasias including dysplasia. However, endoscopic identification of dysplastic lesions is still not sufficiently reliable or subjective, making targeted therapy extremely difficult. Over the past few years, improvements in image resolution, image processing software, and optical filter technology have enabled identification of dysplasia and early cancer in BE patients. We retrieved as many studies on advanced endoscopic technologies in BE as possible from MEDLINE and PubMed. The present review focuses on the emergent clinically available technologies to provide an overview of the technologies, their practical applicability, current status, and future challenges.

Oesophageal carcinoma

Oesophageal carcinoma affects more than 450,000 people worldwide and the incidence is rapidly increasing. Squamous-cell carcinoma is the predominant form of oesophageal carcinoma worldwide, but a shift in epidemiology has been seen in Australia, the UK, the USA, and some western European countries (eg, Finland, France, and the Netherlands), where the incidence of adenocarcinoma now exceeds that of squamous-cell types. The overall 5-year survival of patients with oesophageal carcinoma ranges from 15% to 25%. Diagnoses made at earlier stages are associated with better outcomes than those made at later stages. In this Seminar we discuss the epidemiology, pathophysiology, diagnosis and staging, management, prevention, and advances in the treatment of oesophageal carcinoma.

Prevalence of adenocarcinoma at esophagectomy for Barrett's esophagus with high grade dysplasia

BACKGROUND

Barrett's esophagus with high grade dysplasia (HGD) may require surgical resection because of the risk of concomitant adenocarcinoma. The prevalence of invasive, occult carcinoma (≥stage 1B) in this setting has varied. We investigated the association of adenocarcinoma at operative resection for high grade dysplasia.

METHODS

Using an electronic medical record, we identified patients who underwent esophagectomy for high grade dysplasia at the University of Pittsburgh Medical Center between 1993 and 2007. Preoperative diagnosis was confirmed by reviewing endoscopic, radiologic and pathology reports. Postoperative pathology reports were compared to the preoperative diagnosis.

RESULTS

68 patients (12 females and 56 males) with a preoperative diagnosis of high grade dysplasia underwent operative resection. The mean age was 64 years (range 36 to 86 years). Of 68 patients, 12 (17.6%) had adenocarcinoma, 2 (2.9%) were downgraded to low grade dysplasia, and 54 (79.4%) were confirmed as HGD. Of the 12 patients with adenocarcinoma, 4 (5.9% of total cohort) had intramucosal cancer (Stage 1A) and 8 (11.7% of total cohort) had invasive cancer with submucosal invasion or more advanced disease. Of the 8 patients with invasive adenocarcinoma, 4 did not have preoperative endoscopic or radiologic testing suggestive of advanced disease.

CONCLUSION

The overall prevalence of adenocarcinoma in association with a preoperative diagnosis of HGD was 17.6%. Invasive adenocarcinoma was present in 11.7% of subjects and was clinically occult in 5.9%.

Screening for oesophageal cancer

Oesophageal cancer is a global health problem with high mortality due to the advanced nature of the disease at presentation; therefore, detection at an early stage significantly improves outcome. Oesophageal squamous-cell cancer is preceded by dysplasia and oesophageal adenocarcinoma is preceded by Barrett's oesophagus, which progresses to cancer via intermediate dysplastic stages. Screening to detect these preneoplastic lesions has the potential to substantially reduce mortality and morbidity. However, the risks and benefits of such programmes to individuals and to society need to be carefully weighed. Endoscopic screening is invasive, costly and error prone owing to sampling bias and the subjective diagnosis of dysplasia. Non-endoscopic cell-sampling methods are less invasive and more cost effective than endoscopy, but the sensitivity and specificity of cytological assessment of atypia has been disappointing. The use of biomarkers to analyse samples collected using pan-oesophageal cell-collection devices may improve diagnostic accuracy; however, further work is required to confirm this. The psychological and economic implications of screening as well as the feasibility of implementing such programmes must also be considered.

Prevalence of Barrett esophagus in first-degree relatives of patients with esophageal adenocarcinoma

AIM

The aim of this study is to determine the prevalence of Barrett esophagus (BE) in first-degree relatives of patients with esophageal adenocarcinoma (EAC) and Barrett high-grade dysplasia (HGD).

METHODS

After Institutional Review Board approval, first-degree relatives of patients with EAC/HGD underwent unsedated ultrathin transnasal endoscopy (UUTNE) with biopsy. BE was suspected if any salmon-colored epithelial tongues were seen above the gastroesophageal junction. A diagnosis of BE was made only if biopsy from these areas confirmed columnar-lined epithelium with intestinal metaplasia.

RESULTS

From 23 families, 47 first-degree relatives underwent ultrathin transnasal endoscopy and 1 patient underwent routine upper endoscopy with sedation as part of this study. The mean age of cases was 44.4 years. All patients tolerated the procedure well and there were no procedure-related complications. BE was suspected in 16 (34%) patients and confirmed in 13 of 16 (27.7%) patients. There were 4 long segments (>3 cm) and 9 short segments (<3 cm) of BE.

CONCLUSION

There is a significantly higher than expected prevalence of BE in first-degree relatives of patients with EAC/HGD. This should be taken in to consideration to develop further screening guidelines. Further work is needed to confirm these findings. Unsedated transnasal endoscopy is a safe and well-tolerated method for BE screening.

Ablative therapies for Barrett's esophagus

Barrett's esophagus has gained increased clinical attention because of its association with esophageal adenocarcinoma, a cancer with increasing incidence and poor survival rates. The goals of ablating Barrett's esophagus are to decrease esophageal cancer rates and to improve overall survival and quality of life. Different techniques have been developed and tested for their effectiveness eradicating Barrett's epithelium. This review assesses the literature associated with different ablative techniques. The safety and efficacy of different techniques are discussed. This review concludes with recommendations for the clinician, including specific strategies for patient care decisions for patients with Barrett's esophagus with varying degrees of dysplasia.

Barrett's esophagus: endoscopic treatments II

The following on endoscopic treatments of Barrett's esophagus includes commentaries on animal experiments on cryotherapy; indications for cryotherapy, choice of dosimetry, number of sessions, and role in Barrett's esophagus and adenocarcinoma; recent technical developments of RFA technology and long-term effects; the comparative effects of diverse ablation procedures and the rate of recurrence following treatment; and the indications for treatment of dysplasia and the role of radiofrequency ablation.

A novel device for ablation of abnormal esophageal mucosa (with video)

BACKGROUND

Current ablation devices for Barrett's esophagus are effective but have significant limitations.

OBJECTIVE

To evaluate a new ablation device.

DESIGN AND SETTING

Laboratory and animal model evaluation of the CryoBalloon, a compliant balloon that is simultaneously inflated and cooled by liquid nitrous oxide delivered by using a small, disposable, handheld unit.

INTERVENTION

Cryoablation of esophageal mucosa was performed in 11 swine. Multiple ablations were created in each animal at various ablation times.

MAIN OUTCOME MEASUREMENTS

Animals were euthanized at 4 days (n = 6) or 28 days (n = 5), and histological assessments were performed. At 4 days, the percentage of esophageal mucosa successfully ablated was measured. At 28 days, the circumference of the esophagus at the center of the ablation zone was measured to assess for stricture formation.

RESULTS

The CryoBalloon was simple to operate, and balloon contact with tissue was easily maintained. As the ablation time was increased from 6 to 12 seconds, the percentage of mucosa ablated increased from below 60% to above 90%. Maximal effect on the mucosa was reached at 12 seconds. Ablation of up to 14 seconds resulted in minimal luminal narrowing. As the ablation duration increased from 14 to 22 seconds, there was progressive stricture formation evident at 28 days. All of the animals tolerated the treatments without difficulty and, regardless of ablation duration, were able to continue oral intake and gain weight after the procedure.

LIMITATIONS

Ablation of normal porcine squamous mucosa may differ from that of human Barrett's esophagus.

CONCLUSION

The CryoBalloon device enables circumferential mucosal ablation in a 1-step process by using a novel, through-the-scope balloon. The maximal effect on the mucosa is achieved with a 12-second application time. Because of its ease of use, this new device merits further study so that we can find its possible role in the treatment of Barrett's esophagus.

A comparison of primary oesophageal squamous epithelial cells with HET-1A in organotypic culture

BACKGROUND INFORMATION

Carcinoma of the oesophagus is the sixth leading cause of cancer death in the western world and is associated with a 5-year survival of less than 15%. Recent evidence suggests that stromal-epithelial interactions are fundamental in carcinogenesis. The advent of co-culture techniques permits the investigation of cross-talk between the stroma and epithelium in a physiological setting. We have characterized a histologically representative oesophageal organotypic model and have used it to compare the most commonly used squamous oesophageal cell line, HET-1A, with primary oesophageal squamous cells for use in studies of the oesophageal epithelium in vitro.

RESULTS

When grown in an organotypic culture with normal fibroblasts, the oesophageal carcinoma cell lines OE21 (squamous) and OE19 (adenocarcinoma) morphologically resembled the tumour of origin with evidence of stromal invasion and mucus production, respectively. However, HET-1A cells, which were derived from normal squamous oesophageal cells, appeared dysplastic and failed to display evidence of squamous differentiation. By comparison with primary oesophageal epithelial cells, the HET-1A cells were highly proliferative and did not express the epithelial markers E-cadherin or CK5/6 (casein kinase 5/6), or the stratified epithelial marker ΔNp63, but did express the mesenchymal markers vimentin and N-cadherin.

CONCLUSION

Studies of epithelial carcinogenesis will benefit from culture systems which allow manipulation of the stromal and epithelial layers independently. We have developed an organotypic culture using primary oesophageal squamous cells and fibroblasts in which a stratified epithelium with a proliferative basal layer that stains strongly for ΔNp63 develops. This model will be suitable for the study of the molecular events in the development of Barrett's oesophagus. The most commonly used normal oesophageal squamous cell line, HET-1A, does not have the characteristics of normal oesophageal squamous cells and should not be used in models of the normal oesophageal epithelium. Until more representative cell lines are available, future studies in oesophageal cancer will be reliant on the availability and manipulation of primary tissue.