Argon beam plasma coagulation as therapy for high-grade dysplasia in Barrett's esophagus

Efficacy and Safety of Argon Plasma Coagulation for the Ablation of Barrett's Esophagus: A Systemic Review and Meta-Analysis

Background/Aims

Argon plasma coagulation (APC) is an alternate ablative method to radiofrequency ablation for the treatment of Barrett's esophagus (BE), and it is preferred due to its lower cost and widespread availability. The present meta-analysis aimed to analyze the safety and efficacy of APC for the management of BE.

Methods

A literature search from January 2000 to November 2022 was done for studies analyzing the outcome of APC in BE. The primary outcomes were clearance rate of intestinal metaplasia and adverse events (AE). Pooled event rates were expressed with summative statistics.

Results

A total of 38 studies were included in the final analysis. The pooled event rate for clearance rate of intestinal metaplasia with APC in BE was 86.8% (95% confidence interval [CI], 83.5% to 90.2%), with high-power and hybrid APC having a higher rate compared to standard APC. The pooled incidence of AE with APC in BE was 22.5% (95% CI, 15.3% to 29.7%), without any significant difference between the subgroups, with self-limited chest pain being the commonest AE. The incidence of serious AE was only 0.4% (95% CI, 0.0% to 1.0%), while stricture development was seen only in 1.7% (95% CI, 0.9% to 2.6%) of cases. The pooled recurrence rate of BE was 16.1% (95% CI, 10.7% to 21.6%), with a significantly lower recurrence with high-power APC than standard APC.

Conclusions

High-power and hybrid APC seem to have an advantage over standard APC in terms of clearance rate and recurrence rate. Further studies are required to compare the efficacy and safety of hybrid APC with standard APC and radiofrequency ablation.

Esophageal Cancer: An Updated Review

The incidence of esophageal cancer (EC) is on the rise. With the distinct subtypes of adenocarcinoma and squamous cell carcinoma comes specific risk factors, and as a result, people of certain regions of the world can be more prone to a subtype. For example, squamous cell carcinoma of the esophagus has the highest incidence in eastern Africa and eastern Asia, with smoking being a major risk factor, whereas adenocarcinoma is more prevalent in North America and western Europe, with gastroesophageal reflux disease being a leading risk factor. With that being said, adenocarcinoma and squamous cell carcinoma have similar and unfortunately poor survival rates, partly because EC is prone to early metastasis given that the esophagus does not have a serosa, as well as the superficial nature of its lymphatics compared with the rest of the gastrointestinal tract. This makes early detection of the utmost importance, and certain patients have been shown to have the benefit of screening/surveillance endoscopies, including those with Barrett's esophagus, lye-induced/caustic strictures, tylosis, and Peutz-Jeghers syndrome. Until treatments significantly improve, identifying EC at the earliest stage will have the best success for patient outcomes, and further elucidation of its pathogenesis and risk factors may lead to identifying other high-risk groups that should be screened.

Surgery versus radical endotherapies for early cancer and high-grade dysplasia in Barrett's oesophagus

BACKGROUND

Barrett's oesophagus is one of the most common pre-malignant lesions in the world. Currently the mainstay of therapy is surgical management of advanced cancer but this has improved the five-year survival very little since the 1980s. As a consequence, improved survival relies on early detection through endoscopic surveillance programmes. Success of this strategy relies on the fact that late-stage pre-malignant lesions or very early cancers can be cured by intervention. Currently there is considerable controversy over which method is best: that is conventional open surgery or endotherapy (techniques involving endoscopy).

OBJECTIVES

We used data from randomised controlled trials (RCTs) to examine the effectiveness of endotherapies compared with surgery in people with Barrett's oesophagus, those with early neoplasias (defined as high-grade dysplasia (HGD) and those with early cancer (defined as carcinoma in-situ, superficially invasive, early cancer or superficial cancer T-1m (T1-a) and T-1sm (T1-b)).

SEARCH METHODS

We used the Cochrane highly sensitive search strategy to identify RCTs in MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), ISI Web of Science, EBMR, Controlled Trials mRCT and ISRCTN, and LILACS, in July and August 2008. The searches were updated in 2009 and again in April 2012.

SELECTION CRITERIA

Types of studies: RCTs comparing endotherapies with surgery in the treatment of high-grade dysplasia or early cancer. All cellular types of cancer were included (i.e. adenocarcinomas, squamous cell carcinomas and more unusual types) but will be discussed separately.

TYPES OF PARTICIPANTS

patients of any age and either gender with a histologically confirmed diagnosis of early neoplasia (HGD and early cancer) in Barrett's or squamous lined oesophagus. Types of interventions; endotherapies (the intervention) compared with surgery (the control), all with curative intent.

DATA COLLECTION AND ANALYSIS

Reports of studies that meet the inclusion criteria for this review would have been analysed using the methods detailed in Appendix 9.

MAIN RESULTS

We did not identify any studies that met the inclusion criteria. In total we excluded 13 studies that were not RCTs but that compared surgery and endotherapies.

AUTHORS' CONCLUSIONS

This Cochrane review has indicated that there are no RCTs to compare management options in this vital area, therefore trials should be undertaken as a matter of urgency. The problems with such randomised methods are standardising surgery and endotherapies in all sites, standardising histopathology in all centres, assessing which patients are fit or unfit for surgery and making sure there are relevant outcomes for the study (i.e. long-term survival (over five or more years)) and no progression of HGD.

Radiofrequency ablation compared with argon plasma coagulation after endoscopic resection of high-grade dysplasia or stage T1 adenocarcinoma in Barrett's esophagus: a randomized pilot study (BRIDE)

BACKGROUND AND AIMS

Endoscopic resection (ER) is safe and effective for Barrett's esophagus (BE) containing high-grade dysplasia (HGD) or mucosal adenocarcinoma (T1A). The risk of metachronous neoplasia is reduced by ablation of residual BE by using radiofrequency ablation (RFA) or argon plasma coagulation (APC). These have not been compared directly. We aimed to recruit up to 100 patients with BE and HGD or T1A confirmed by ER over 1 year in 6 centers in a randomized pilot study.

METHODS

Randomization was 1:1 to RFA or APC (4 treatments allowed at 2-month intervals). Recruitment, retention, dysplasia clearance, clearance of benign BE, adverse events, healthcare costs, and quality of life by using EQ-5D, EORTC QLQ-C30, or OES18 were assessed up to the end of the trial at 12 months.

RESULTS

Of 171 patients screened, 76 were randomized to RFA (n = 36) or APC (n = 40). The mean age was 69.7 years, and 82% were male. BE was <5 cm (n = 27), 5 to 10 cm (n = 45), and >10 cm (n = 4). Sixty-five patients completed the trial. At 12 months, dysplasia clearance was RFA 79.4% and APC 83.8% (odds ratio [OR] 0.7; 95% confidence interval [CI], 0.2-2.6); BE clearance was RFA 55.8%, and APC 48.3% (OR 1.4; 95% CI, 0.5-3.6). A total of 6.1% (RFA) and 13.3% (APC) had buried BE glands. Adverse events (including stricture rate after starting RFA 3/36 [8.3%] and APC 3/37 [8.1%]) and quality of life scores were similar, but RFA cost $27491 more per case than APC.

CONCLUSION

This pilot study suggests similar efficacy and safety but a cost difference favoring APC. A fully powered non-inferiority trial is appropriate to confirm these findings. (Clinical trial registration number: NCT01733719.).

Endoscopic therapy for Barrett’s esophagus and early esophageal cancer: Where do we go from here?

Since Barrett’s esophagus is a precancerous condition, efforts have been made for its eradication by various ablative techniques. Initially, laser ablation was attempted in non-dysplastic Barrett’s esophagus and subsequently, endoscopic ablation using photodynamic therapy was used in Barrett’s patients with high-grade dysplasia who were poor surgical candidates. Since then, various ablative therapies have been developed with radiofrequency ablation having the best quality of evidence. Resection of dysplastic areas only without complete removal of entire Barrett’s segment is associated with high risk of developing metachronous neoplasia. Hence, the current standard of management for Barrett’s esophagus includes endoscopic mucosal resection of visible abnormalities followed by ablation to eradicate remaining Barrett’s epithelium. Although endoscopic therapy cannot address regional lymph node metastases, such nodal involvement is present in only 1% to 2% of patients with intramucosal adenocarcinoma in Barrett esophagus and therefore is useful in intramucosal cancers. Post ablation surveillance is recommended as recurrence of intestinal metaplasia and dysplasia have been reported. This review includes a discussion of the technique, efficacy and complication rate of currently available ablation techniques such as radiofrequency ablation, cryotherapy, argon plasma coagulation and photodynamic therapy as well as endoscopic mucosal resection. A brief discussion of the emerging technique, endoscopic submucosal dissection is also included.

Radiofrequency ablation in patients with large cervical heterotopic gastric mucosa and globus sensation: Closing the treatment gap

BACKGROUND AND AIM

Symptomatic cervical heterotopic gastric mucosa, also known as cervical inlet patch (CIP), may present in various shapes and causes laryngopharyngeal reflux (LPR). Unfortunately, argon plasma coagulation, standard treatment of small symptomatic CIP, is limited in large CIP mainly because of concerns of stricture formation. Therefore, we aimed to investigate radiofrequency ablation (RFA), a novel minimally invasive ablation method, in the treatment of CIP focusing on large symptomatic patches.

METHODS

Consecutive patients with macroscopic and histological evidence of large (≥20 mm diameter) heterotopic gastric mucosa were included in this prospective trial. Primary outcome was complete macroscopic and histological eradication rate of CIP. Secondary outcome measures were symptom improvement, quality of life, severity of LPR and adverse events.

RESULTS

Ten patients (females, n = 5) underwent RFA of symptomatic CIP. Complete histological and macroscopic eradication of CIP was observed in 80% (females, n = 4) of individuals after two ablations. Globus sensations significantly improved from median visual analog scale score 8 (5-9) at baseline to 1.5 (1-7) after first ablation and 1 (1-2) after final evaluation (P < 0.001). Mental health scores significantly increased from 41.4 (± 8.5) to 54.4 (± 4.4) after RFA (P = 0.007). LPR improved significantly (P = 0.005) with absence of strictures after a mean follow up of 1.9 (± 0.5) years.

CONCLUSIONS

This is the first study on RFA focusing on therapy of large symptomatic heterotopic gastric mucosa. Hereby, we demonstrate that this new technique can be successfully implemented in patients where treatment was limited so far (NCT03023280).

Endoscopic Management of Early Esophagogastric Cancer

Esophagogastric cancer accounts for the second most common cause of cancer-related mortality worldwide. Significant efforts have been made to detect these malignancies at an earlier stage through the implementation of screening programs in high-risk individuals using advanced diagnostic techniques. Endoscopic management techniques, such as endoscopic mucosal resection and endoscopic submucosal dissection, have consistently demonstrated excellent outcomes in the management of these lesions. These techniques are associated with a lower risk of morbidity and mortality when compared with traditional surgical management.

Role of endoscopy in early oesophageal cancer

Incidence of oesophageal adenocarcinoma has increased exponentially in the West over the past few decades. Following detection of advanced cancers, 5-year survival rates remain bleak, making identification of early neoplasia, which has a better outcome, important. Detection of subtle oesophageal lesions during endoscopy can be challenging, and advanced imaging techniques might improve their detection. High-definition endoscopy has become a standard in most endoscopy centres, and this technology probably provides better delineation of mucosal features than standard-definition endoscopy. Various image enhancement techniques are now available with the development of new electronics and software systems. Image enhancement with chromoendoscopy using dyes has been a cost-effective option for many years, yet these techniques have been replaced in some contexts by electronic chromoendoscopy, which can be used with the press of a button. However, Lugol's chromoendoscopy remains the gold standard to identify squamous dysplasia. Identification and characterization of subtle neoplastic lesions could help to target biopsies and perform endoscopic resection for better local staging and definitive therapy. In vivo histology with techniques such as confocal endomicroscopy could make endotherapy feasible within a shorter timescale than when relying on histology on tissue samples. Once early neoplasia is identified, treatments include endoscopic resection, endoscopic submucosal dissection or various ablative techniques. Endotherapy has the advantage of being a less invasive technique than oesophagectomy, and is associated with lower mortality and morbidity. Endoscopic ablation therapies have evolved over the past few years, with radiofrequency ablation showing the best results in terms of success rates and complications in Barrett dysplasia.

Endoscopic Management of Early Esophageal Cancer

The absolute incidence of esophageal adenocarcinoma has increased 7-fold over the past 5 decades, and esophageal adenocarcinoma is the most rapidly increasing epithelial malignancy in the United States. The incidence of early esophageal cancer has also increased proportionately. In the past decade, radiofrequency ablation has become the standard first-line therapy for high-grade dysplasia when found in the precursor lesion to esophageal adenocarcinoma, Barrett's esophagus. Success in the endoscopic management of high-grade dysplasia has furthered efforts to treat early esophageal cancers endoscopically. Although surgery remains the mainstay of treatment for more advanced tumors, national guidelines now recommend endoscopic mucosal resection followed by radiofrequency ablation for intramucosal carcinomas and T1a cancers. T1b cancers represent a more challenging group-very good results have been reported in highly selected subsets of patients with T1b tumors; however, many recommendations favor individualization or a surgical approach for this stage. This review examines the current data and recommendations regarding the endoscopic management of early esophageal adenocarcinomas.

Prediction of response to endoscopic therapy of Barrett's dysplasia by using genetic biomarkers

BACKGROUND

Endoscopic therapy for the treatment of high-grade dysplasia (HGD) and intramucosal cancer (IMC) in Barrett's esophagus (BE) may not always result in complete remission of dysplasia (CRD).

OBJECTIVE

To determine whether genetic alterations in the Barrett's mucosa can predict response to endoscopic therapy.

DESIGN

Retrospective cohort study.

SETTING

Tertiary-care institution.

PATIENTS

Selected patients who underwent endoscopic therapy for BE containing HGD/IMC between 2003 and 2010.

INTERVENTIONS

Endoscopic therapy combining mucosal resection and different ablation modalities was performed based on patient characteristics, endoscopic findings, and technique evolution. Fluorescence in situ hybridization was used to evaluate genetic alterations on baseline endoscopic cytology brushings by using probes directed to loci 8q24 (MYC), 9p21 (CDKN2A; alias P16), 17q12 (ERBB2; alias Her-2/neu), and 20q13.2 (ZNF217).

MAIN OUTCOME MEASUREMENTS

Genetic biomarkers predicting achievement of CRD after endoscopic therapy.

RESULTS

A total of 181 patients were included (145 men; 66 ± 10 years of age). There were 130 patients (72%) who responded to endoscopic therapy with CRD. Multiple gains detected by fluorescence in situ hybridization was found to be a negative predictor (hazard ratio 0.57; 95% confidence interval, 0.40-0.82) after adjusting for potential clinical confounders. Similar results were found when analyses were restricted to patients (n = 66) undergoing radiofrequency ablation (hazard ratio 0.58; 95% confidence interval, 0.31-1.09).

LIMITATIONS

Retrospective study, heterogeneity of treatment modalities.

CONCLUSION

Patients with multiple gains detected by brush cytology specimens may have a lower response rate to endoscopic therapy. The presence of multiple gains can be an adjunct to standard histology in prognosticating BE patients with HGD/IMC undergoing endoscopic therapy.

Ablative therapy for esophageal dysplasia and early malignancy: focus on RFA

Ablative therapies have been utilized with increasing frequency for the treatment of Barrett's esophagus with and without dysplasia. Multiple modalities are available for topical ablation of the esophagus, but radiofrequency ablation (RFA) remains the most commonly used. There have been significant advances in technique since the introduction of RFA. The aim of this paper is to review the indications, techniques, outcomes, and most common complications following esophageal ablation with RFA.

Therapeutic endoscopy and endoscopic ultrasound for gastrointestinal malignancies

Gastrointestinal endoscopy and endoscopic ultrasound not only provide strategies to diagnose and stage malignancy, but also to administer palliative and definitive care. Options for anticancer therapy include endoscopic mucosal resection, photodynamic therapy, thermal therapy, self-expanding metal stents and recently, endoscopic ultrasound-guided therapy, such as intratumoral injection. This review summarizes the available endoscopic techniques with a discussion of indications and recent clinical data pertaining to gastrointestinal malignancy. This review will inform the reader of emerging treatment options and stress the importance of incorporating gastroenterologists into the multidisciplinary approach in the management of gastrointestinal cancers.

Optical coherence tomography in Barrett's esophagus

The incidence of Barrett's-related adenocarcinoma of the esophagus continues to increase at an alarming rate. Studies to date show great promise for optical coherence tomography (OCT) in screening, surveillance, and guiding management of Barrett's esophagus. With continued innovation in rapid, accurate scanning systems, such as volumetric laser endomicroscopy or optical frequency domain imaging, advanced OCT seems likely to have an important impact. The next few years are likely to see the initiation of large clinical studies that will define the extent and significance of this impact.

A submucosal tumor-like recurrence of early esophageal cancer after endoscopic submucosal dissection

Early esophageal cancer is defined as a tumor invading the mucosa with or without lymph node or distant organ metastasis. In the current guidelines for early esophageal cancer, absolute indication for endoscopic resection include lesions limited to the epithelium or lamina propria mucosa not exceeding two-thirds of the circumference, and relative indications include lesions limited to the muscularis mucosa or the upper third of the submucosal layer and not accompanied by clinical evidence of lymph node metastasis. After endoscopic submucosal dissection for early esophageal cancer, locally recurrent cancer can occur, especially in the case of incomplete resection. Here, we report a rare case of a submucosal tumor-like recurrence after endoscopic resection of early esophageal cancer.

Endoscopic therapy for Barrett's esophagus and early esophageal adenocarcinoma

Endoscopic therapy for Barrett's esophagus is feasible and likely to decrease the future risk of development of esophageal adenocarcinoma. The most commonly used therapy is radiofrequency ablation, which has been shown to produce reproducible superficial injury in the esophagus. Other thermal therapies include multipolar coagulation, argon plasma coagulation, and thermal laser therapy. The other end of the ablative spectrum includes cryotherapy, which involves freezing tissue to produce mucosal necrosis. Photodynamic therapy has been used to photochemically eliminate abnormal mucosa. Endoscopic therapy has been demonstrated to be effective in high-risk situations such as Barrett's esophagus with high-grade dysplasia.

Endoscopic management of Barrett's esophagus: advances in endoscopic techniques

Barrett's esophagus (BE) is a well-known premalignant condition that can be associated with the development of dysplasia and adenocarcinoma. In the past, esophagectomy was the standard treatment for patients with BE with high grade dysplasia (HGD) and early cancer (EC). However, esophagectomy is not necessarily the only treatment response to HGD and EC anymore. Over the past decade, a number of endoscopic therapies have been developed for management of BE. These include endoscopic mucosal resection, thermal ablation techniques that use laser irradiation, multipolar electrocoagulation, argon plasma coagulation, photodynamic therapy, and the recently developed cryotherapy and radiofrequency ablation.

Surgery versus radical endotherapies for early cancer and high-grade dysplasia in Barrett's oesophagus

BACKGROUND

Barrett's oesophagus is one of the most common pre-malignant lesions in the world. Currently the mainstay of therapy is surgical management of advanced cancer but this has improved the five-year survival very little since the 1980s. As a consequence, improved survival relies on early detection through endoscopic surveillance programmes. Success of this strategy relies on the fact that late-stage pre-malignant lesions or very early cancers can be cured by intervention. Currently there is considerable controversy over which method is best: that is conventional open surgery or endotherapy (techniques involving endoscopy).

OBJECTIVES

We used data from randomised controlled trials (RCTs) to examine the effectiveness of endotherapies compared with surgery in people with Barrett's oesophagus, those with early neoplasias (defined as high-grade dysplasia (HGD) and those with early cancer (defined as carcinoma in-situ, superficially invasive, early cancer or superficial cancer T-1m (T1-a) and T-1sm (T1-b)).

SEARCH METHODS

We used the Cochrane highly sensitive search strategy to identify RCTs in MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), ISI Web of Science, EBMR, Controlled Trials mRCT and ISRCTN, and LILACS, in July and August 2008. The searches were updated in 2009 and again in April 2012.

SELECTION CRITERIA

Types of studies: RCTs comparing endotherapies with surgery in the treatment of or early cancer. All cellular types of cancer were included (i.e. adenocarcinomas, squamous cell carcinomas and more unusual types) but will be discussed separately.

TYPES OF PARTICIPANTS

patients of any age and either gender with a histologically confirmed diagnosis of early neoplasia (HGD and early cancer) in Barrett's or squamous lined oesophagus.Types of interventions; endotherapies (the intervention) compared with surgery (the control), all with curative intent.

DATA COLLECTION AND ANALYSIS

Reports of studies that meet the inclusion criteria for this review would have been analysed using the methods detailed in Appendix 9.

MAIN RESULTS

We did not identify any studies that met the inclusion criteria. In total we excluded 13 studies that were not RCTs but that compared surgery and endotherapies.

AUTHORS' CONCLUSIONS

This Cochrane review has indicated that there are no RCTs to compare management options in this vital area, therefore trials should be undertaken as a matter of urgency. The problems with such randomised methods are standardising surgery and endotherapies in all sites, standardising histopathology in all centres, assessing which patients are fit or unfit for surgery and making sure there are relevant outcomes for the study (i.e. long-term survival (over five or more years)) and no progression of HGD.

Natural history of Barrett's esophagus

The natural history of Barrett’s esophagus (BE) is difficult to quantify because, by definition, it should describe the course of the condition if left untreated. Pragmatically, we assume that patients with BE will receive symptomatic treatment with acid suppression, usually a proton pump inhibitor, to treat their heartburn. This paper describes the development of complications of stricture, ulcer, dysplasia and adenocarcinoma from this standpoint. Controversies over the definition of BE and its implications in clinical practice are presented. The presence of intestinal metaplasia and its relevance to cancer risk is discussed, and the need to measure the extent of the Barrett’s epithelium (long and short segments) using the Prague guidelines is emphasized. Guidelines and international consensus over the diagnosis and management of BE are being regularly updated. The need for expert consensus is important due to the lack of randomized trials in this area. After searching the literature, we have tried to collate the important studies regarding progression of Barrett’s to dysplasia and adenocarcinoma. No therapeutic studies yet reported show a clear reduction in the development of cancer in BE. The effect of pharmacological and surgical intervention on the natural history of Barrett’s is a subject of ongoing research, including the Barrett’s Oesophagus Surveillance Study and the aspirin and esomeprazole cancer chemoprevention trial with interesting results. The geographical variation and the wide range of outcomes highlight the difficulty of providing an individualized risk profile to patients with BE. Future studies on the interaction of genome wide abnormalities in Barrett’s and their interaction with environmental factors may allow individualization of the risk of cancer developing in BE.

Endoscopic therapies for the prevention and treatment of early esophageal neoplasia

Esophageal cancers have traditionally been diagnosed late and prognosis has been dire. For many years the only real treatment option was esophagectomy with substantial morbidity and mortality. This situation has now changed dramatically. Improvements have been achieved in surgical outcomes and there is an array of new effective treatment options now available, particularly for the increasing proportion diagnosed with early-stage disease. Minimally invasive endoscopic therapies can now prevent, cure or palliate esophageal cancers. This article aims to investigate the role and evidence base for these new therapeutic options.

Endoscopic resection techniques and ablative therapies for Barrett’s neoplasia

Esophageal adenocarcinoma is the most rapidly increasing cancer in western countries. High-grade dysplasia (HGD) arising from Barrett’s esophagus (BE) is the most important risk factor for its development, and when it is present the reported incidence is up to 10% per patient-year. Adenocarcinoma in the setting of BE develops through a well known histological sequence, from non-dysplastic Barrett’s to low grade dysplasia and then HGD and cancer. Endoscopic surveillance programs have been established to detect the presence of neoplasia at a potentially curative stage. Newly developed endoscopic treatments have dramatically changed the therapeutic approach of BE. When neoplasia is confined to the mucosal layer the risk for developing lymph node metastasis is negligible and can be successfully eradicated by an endoscopic approach, offering a curative intention treatment with minimal invasiveness. Endoscopic therapies include resection techniques, also known as tissue-acquiring modalities, and ablation therapies or non-tissue acquiring modalities. The aim of endoscopic treatment is to eradicate the whole Barrett’s segment, since the risk of developing synchronous and metachronous lesions due to the persistence of molecular aberrations in the residual epithelium is well established.

Comparison of COX-2, Ki-67, and BCL-2 expression in normal esophageal mucosa, Barrett's esophagus, dysplasia, and adenocarcinoma with postablation mucosa and implications for ablative therapies

BACKGROUND

The neosquamous mucosa that replaces ablated esophageal endothelium after endoscopic mucosal ablation for Barrett's metaplasia or high-grade dysplasia (HGD) may retain buried glandular tissue. This study aimed to assess the neoplastic potential, cellular proliferation, and resistance to apoptosis of this buried glandular tissue by measuring COX-2, Ki-67, and BCL-2 expression in these tissues.

METHODS

A prospectively collected database was sourced for esophageal biopsy specimens with normal histologic appearance, Barrett's metaplasia, HGD, adenocarcinoma, and postablation mucosa comprising ablated Barrett's and ablated HGD. Quantitative analysis of cellular markers was achieved immunohistochemically using monoclonal antibodies for the COX-2 enzyme (suggesting increased neoplastic potential), Ki-67 antigen (suggesting cellular proliferation), and BCL-2 oncoprotein (suggesting oncogenic resistance to apoptosis). Grading was performed by independent, blinded observers, and the pre- and postablation cellular disparities were subsequently noted.

RESULTS

The buried glandular elements of postablation mucosa demonstrated universally greater COX-2, Ki-67, and BCL-2 expression than normal esophagus. Barrett's esophagus and adenocarcinoma expressed significantly greater COX-2 and Ki-67 at the deep glandular level than postablation mucosa. HGD demonstrated greater Ki-67 expression than the postablation tissue but only within the superficial glands. Overall, the expression of COX-2 correlated significantly with Ki-67 expression in deep glandular tissue.

CONCLUSIONS

Ablation of pathologic mucosa in Barrett's esophagus and HGD reduces the expression of some markers of neoplastic behavior. However, the buried glandular tissue of the postablation mucosa still exhibits a higher expression than normal esophageal epithelium. This has potential implications for the follow-up treatment of these patients because it is unclear whether the true risk of neoplastic progression is adequately reduced. A more comprehensive study is required to address this issue.

Advances in endoscopic diagnosis and treatment of Barrett's esophagus

Barrett's esophagus (BE) is defined as abnormal specialized columnar metaplasia with intestinalization in place of the normal squamous esophageal epithelium. Gastroesophageal reflux disease is a known risk factor for BE; nonetheless BE is also detected in asymptomatic individuals. Other risk factors for BE include smoking, male gender, age over 50 and obesity. Patients diagnosed with BE (without dysplasia) are recommended to undergo endoscopic surveillance every 3-5 years. Advances in imaging techniques (such as narrow band imaging, autofluorescence imaging and confocal laser endomicroscopy) have the potential to improve the detection of dysplasia and early cancer, thus making surveillance a more cost-effective endeavor. Patients with high grade dysplasia (HGD) and early cancer have a high rate of progression to invasive adenocarcinoma and traditionally these patients were treated with esophagectomy. The rapid advancement of endoscopic therapeutic techniques along with a low risk of complications have made endoscopic therapy an acceptable alternative to an esophagectomy in patients with HGD and early cancer. Several endoscopic treatment techniques such as endoscopic mucosal resection, multipolar electrocoagulation, photodynamic therapy, argon plasma coagulation, cryotherapy, and radiofrequency ablation have been studied for endoscopic treatment.

Endoscopic treatments for Barrett's esophagus: a systematic review of safety and effectiveness compared to esophagectomy

BACKGROUND

Recently, several new endoscopic treatments have been used to treat patients with Barrett's esophagus with high grade dysplasia. This systematic review aimed to determine the safety and effectiveness of these treatments compared with esophagectomy.

METHODS

A comprehensive literature search was undertaken to identify studies of endoscopic treatments for Barrett's esophagus or early stage esophageal cancer. Information from the selected studies was extracted by two independent reviewers. Study quality was assessed and information was tabulated to identify trends or patterns. Results were pooled across studies for each outcome. Safety (occurrence of adverse events) and effectiveness (complete eradication of dysplasia) were compared across different treatments.

RESULTS

The 101 studies that met the selection criteria included 8 endoscopic techniques and esophagectomy; only 12 were comparative studies. The quality of evidence was generally low. Methods and outcomes were inconsistently reported. Protocols, outcomes measured, follow-up times and numbers of treatment sessions varied, making it difficult to calculate pooled estimates.The surgical mortality rate was 1.2%, compared to 0.04% in 2831 patients treated endoscopically (1 death). Adverse events were more severe and frequent with esophagectomy, and included anastomotic leaks (9.4%), wound infections (4.1%) and pulmonary complications (4.1%). Four patients (0.1%) treated endoscopically experienced bleeding requiring transfusions. The stricture rate with esophagectomy (5.3%) was lower than with porfimer sodium photodynamic therapy (18.5%), but higher than aminolevulinic acid (ALA) 60 mg/kg PDT (1.4%). Dysphagia and odynophagia varied in frequency across modalities, with the highest rates reported for multipolar electrocoagulation (MPEC). Photosensitivity, an adverse event that occurs only with photodynamic therapy, was experienced by 26.4% of patients who received porfimer sodium.Some radiofrequency ablation (RFA) or argon plasma coagulation (APC) studies (used in multiple sessions) reported rates of almost 100% for complete eradication of dysplasia. But the study methods and findings were not adequately described. The other studies of endoscopic treatments reported similarly high rates of complete eradication.

CONCLUSIONS

Endoscopic treatments offer safe and effective alternatives to esophagectomy for patients with Barrett's esophagus and high grade dysplasia. Unfortunately, shortcomings in the published studies make it impossible to determine the comparative effectiveness of each of the endoscopic treatments.

The case for endoscopic treatment of non-dysplastic and low-grade dysplastic Barrett's esophagus

Non-dysplastic mucosa (ND-) in Barrett's esophagus (BE) shows clonal molecular aberrations, loss of cell cycle control, and other features of "neoplasia." These changes occur prior to morphologic expression of neoplasia (dysplasia). Morphologic evaluation of dysplasia is fraught with error, and, as a result, often leads to false-negative and false-positive diagnoses. Early "crypt dysplasia" is difficult to detect, and is often missed in routine biopsy specimens. Some studies show substantial progression rates of low-grade dysplasia (LGD), and crypt dysplasia, to esophageal adenocarcinoma (EAC). Dysplasia, even when fully developed, may, in certain circumstances, be difficult to differentiate from non-dysplastic (regenerating) BE. Radiofrequency ablation (RFA) is a safe and effective method for removing mucosa at risk of cancer. Given the difficulties of dysplasia assessment in mucosal biopsies, and the molecular characteristics of ND-BE, this technique should be considered for treatment of all BE patients, including those with ND or LGD. Post-ablation neo-squamous epithelium reveals no molecular abnormalities, and is biologically stable. Given that prospective randomized controlled trials of ablative therapy for ND-BE aiming at reducing EAC incidence and mortality are unlikely to be completed in the near future, endoscopic ablation is a valid management option. The success of RFA in achieving safe, uniform, reliable, and predictable elimination of BE allows surgeons to combine fundoplication with RFA. Currently, there is no type of treatment for dysplastic or non-dysplastic BE that achieves a complete response in 100% of patients, eliminates all risk of developing cancer, results in zero adverse events, is less expensive in terms of absolute costs than surveillance, is durable for 20+ years, or eliminates the need for surveillance. Regardless, RFA shows established safety, efficacy, durability, and cost-effective profiles that should be considered in the management of patients with non-dysplastic or low-grade dysplastic BE.

Optimal endoluminal treatment of Barrett's esophagus: integrating novel strategies into clinical practice

Endoluminal therapy has become the first-choice treatment over the last 5 years for early Barrett's neoplasia limited to the mucosa. Long-term follow-up data on endoscopic resection have demonstrated the oncological safety of endoscopic resection in comparison to surgery. However, there is a high rate of recurrent disease, which can be avoided using additional ablation of the remaining Barrett. Radiofrequency ablation was recently introduced as an efficacious means to ablate Barrett's epithelium with a better safety profile than older ablation techniques. Recent studies show that endoscopic resection can be safely combined with radiofrequency ablation for treating dysplastic Barrett's after removal of visible lesions. This constitutes a completely new treatment paradigm that will be integrated in routine clinical practice in the forthcoming years.

Surgery versus radical endotherapies for early cancer and high grade dysplasia in Barrett's oesophagus

BACKGROUND

Barrett's oesophagus is one of the most common premalignant lesions in the world. Currently the mainstay of therapy is surgical management of advanced cancer but this has improved the five-year survival very little in the last 30 years. As a consequence, improved survival relies on early detection through endoscopic surveillance programmes. Success of this strategy relies on the fact that late stage premalignant lesions or very early cancers can be cured by intervention. Currently there is considerable controversy over which method is best: i.e. conventional open surgery or endotherapy (techniques involving endoscopy).

OBJECTIVES

We used data from randomised controlled trials to examine the effectiveness of endotherapies compared with surgery, in people with Barrett's Oesophagus; those with early neoplasias (defined as high grade dysplasia (HGD), and those with early cancer (defined as carcinoma in-situ, superficially invasive, early cancer or superficial cancer T-1m (T1-a) and T-1sm (T1-b)).

SEARCH STRATEGY

We used the Cochrane highly sensitive search strategy to identify randomised trials in MEDLINE, EMBASE, CENTRAL, ISI Web of Science, EBMR, Controlled Trials mRCT and ISRCTN and LILACS, in July and August 2008.

SELECTION CRITERIA

Types of studies: randomised controlled trials comparing endotherapies with surgery in the treatment of high grade dysplasia (HGD), or early cancer. All cellular types of cancer were included (i.e. adenocarcinomas, squamous cell carcinomas and more unusual types) but will be discussed separately.

TYPES OF PARTICIPANTS

patients of any age and either gender with a histologically confirmed diagnosis of early neoplasia (HGD and early cancer) in Barrett's or squamous lined oesophagus.Types of interventions; endotherapies (the intervention) compared with surgery (the control), all with curative intent.

DATA COLLECTION AND ANALYSIS

Reports of studies which meet the inclusion criteria for this review would have been analysed using the methods detailed in Appendix 9.

MAIN RESULTS

We did not identify any studies which met the inclusion criteria.

AUTHORS' CONCLUSIONS

This Cochrane review has indicated that there are no randomised control trials to compare management options in this vital area, therefore trials should be undertaken as a matter of urgency. The problems with such randomised methods are standardising surgery and endotherapies in all sites; standardising histopathology in all centres; assessing which patients are fit or unfit for surgery; and making sure there are relevant outcomes for the study i.e. long term survival (over five or more years) and no progression of high grade dysplasia.

History, molecular mechanisms, and endoscopic treatment of Barrett's esophagus

This report is an adjunct to the American Gastroenterological Association Institute's medical position statement and technical review on the management of Barrett's esophagus, which will be published in the near future. Those documents will consider a number of broad questions on the diagnosis, clinical features, and management of patients with Barrett's esophagus, and the reader is referred to the technical review for an in-depth discussion of those topics. In this report, we review historical, molecular, and endoscopic therapeutic aspects of Barrett's esophagus that are of interest to clinicians and researchers.

Treatment for Barrett's oesophagus

BACKGROUND

Treatments for Barrett's oesophagus, the precursor lesion of adenocarcinoma, are available but whether these therapies effectively prevent the development of adenocarcinoma, and in some cases eradicate the Barrett's oesophagus segment, remains unclear.

OBJECTIVES

To summarise, quantify and compare the efficacy of pharmacological, surgical and endoscopic treatments for the eradication of dysplastic and non-dysplastic Barrett's oesophagus and prevention of these states from progression to adenocarcinoma.

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library 2004, issue 4), MEDLINE (1966 to June 2008) and EMBASE (1980 to June 2008).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing medical, endoscopic or non-resectional surgical treatments for Barrett's oesophagus. The primary outcome measures were complete eradication of Barrett's and dysplasia at 12 months, and reduction in the number of patients progressing to cancer at five years or latest time point.

DATA COLLECTION AND ANALYSIS

Three authors independently extracted data and assessed the quality of the trials included in the analysis.

MAIN RESULTS

Sixteen studies, including 1074 patients, were included. The mean number of participants in the studies was small (n = 49; range 8 to 208). Most studies did not report on the primary outcomes. Medical and surgical interventions to reduce symptoms and sequelae of gastro-oesophageal reflux disease (GORD) did not induce significant eradication of Barrett's oesophagus or dysplasia. Endoscopic therapies (photodynamic therapy (PDT with aminolevulinic acid or porfimer sodium), argon plasma coagulation (APC) and radiofrequency ablation (RFA)) all induced regression of Barrett's oesophagus and dysplasia. The data for photodynamic therapy were heterogeneous with a mean eradication rate of 51% for Barrett's oesophagus and between 56% and 100% for dysplasia, depending on the treatment regimens. The variation in photodynamic therapy eradication rates for dysplasia was dependent on the drug, source and dose of light. Radiofrequency ablation resulted in eradication rates of 82% and 94% for Barrett's oesophagus and dysplasia respectively, compared to a sham treatment. Endoscopic treatments were generally well tolerated, however all were associated with some buried glands, particularly following argon plasma coagulation and photodynamic therapy, as well as photosensitivity and strictures induced by porfimer sodium based photodynamic therapy in particular.

AUTHORS' CONCLUSIONS

Despite their failure to eradicate Barrett's oesophagus, the role of medical and surgical interventions to reduce the troubling symptoms and sequelae of GORD is not questioned. Whether therapies for GORD reduce the cancer risk is not yet known. Ablative therapies have an increasing role in the management of dysplasia within Barrett's and current data would favour the use of radiofrequency ablation compared with photodynamic therapy. Radiofrequency ablation has been shown to yield significantly fewer complications than photodynamic therapy and is very efficacious at eradicating both dysplasia and Barrett's itself. However, long-term follow-up data are still needed before radiofrequency ablation can be used in routine clinical care without the need for very careful post-treatment surveillance. More clinical trial data and in particular randomised controlled trials are required to assess whether or not the cancer risk is reduced in routine clinical practice.

Complete Barrett's eradication endoscopic mucosal resection: an effective treatment modality for high-grade dysplasia and intramucosal carcinoma--an American single-center experience

OBJECTIVES

Complete Barrett's eradication endoscopic mucosal resection (CBE-EMR) is the endoscopic removal of all Barrett's epithelium with the curative intent of eliminating high-grade dysplasia (HGD)/intramucosal carcinoma (IMC) and reducing the risk of metachronous lesion development. We report our single tertiary referral center's long-term clinical experience using this modality in HGD/IMC management.

METHODS

In this study, we retrospectively reviewed all patients who had CBE-EMR for Barrett's esophagus (BE) with HGD/IMC who had been entered into our center's prospectively collected database. High-definition white-light and narrow-band imaging examinations were used according to the protocol. Staging endoscopic ultrasound was done before CBE-EMR to exclude invasive disease or suspicious lymphadenopathy. High-dose proton pump inhibition was instituted after initial treatment, and Seattle-type surveillance biopsies were performed on follow-up every 6 months once the CBE-EMR procedure was completed.

RESULTS

A total of 49 patients (mean age 67 years, median 65, s.d. 11; 75% men) with histologically confirmed BE and HGD (33), IMC (16), underwent CBE-EMR from August 2003 to August 2008. The mean BE segment length was 3.2 cm (median 2, s.d. 2.2); 26 patients had short-segment BE, and 30 had visible lesions. A total of 106 EMR procedures were performed. On initial EMR, two patients had superficial submucosal carcinoma invasion (sm1) and two had IMC with lymphatic channel invasion. All four patients were referred for esophagectomy, but one opted for continued endoscopic management, without evidence of residual or recurrent carcinoma. A total of 14 patients await completion of EMR (9) or first follow-up endoscopy (5). CBE-EMR therapy was completed in 32 patients by an average of 2.1 sessions (median 2, s.d. 0.9). Surveillance biopsies showed normal squamous epithelium in 31 of 32 (96.9%) patients (mean remission time 22.9 months, median 17, s.d. 16.7, interquartile range 11-38). In all, 10 of 46 patients who continued in the endoscopic protocol had subsquamous Barrett's epithelium on EMR specimens and/or treatment endoscopy biopsies. Overall, 1 of these 10 patients had Barrett's underneath squamous mucosa on most recent surveillance biopsies. CBE-EMR upstaged pre-EMR pathology results in 7 of 49 (14%) of patients and downstaged pathology in 15 of 49 (31%) patients. In all, 18 of 49 (37%) patients developed symptomatic esophageal stenosis after a mean of 24.4 days (median 13.5, s.d. 27.8); all were successfully managed by endoscopic treatment. No perforations or uncontrollable bleeding occurred.

CONCLUSIONS

To our knowledge, this is the largest American single-center experience demonstrating that CBE-EMR with close endoscopic surveillance is an effective treatment modality for BE with HGD/IMC. Although the rate of stenosis development is significant, it is easily treated by endoscopic dilation. Patients considering endoscopic ablation should be counseled appropriately. The role of CBE-EMR in patients with lymphatic invasion or superficial submucosal invasion remains to be defined.

Endoscopic therapy for Barrett's esophagus

Recent retrospective cohort data and a prospective randomized sham controlled trial have clearly documented the impact of endoscopic ablation therapy on dysplasia and Barrett's esophagus (BE). The clinical indications for ablation of BE includes high-grade dysplasia and intramucosal adenocarcinoma. The techniques of resection of mucosal irregularities and of ablation are reviewed, primarily thermal and photodynamic ablation. Ablation of BE with neoplasia has appropriately entered the clinical arena.

Mucosal ablation of Barrett esophagus

The management of Barrett esophagus is evolving with the emergence of new endoscopic technologies. Traditionally, patients with high-grade dysplasia or cancer were referred for esophagectomy. However, with the advent of endoscopic ablative therapies for Barrett esophagus, the treatment paradigm has shifted. Patients with high-grade dysplasia and intramucosal carcinoma are increasingly offered esophagus-sparing therapies. Endoscopic ablative therapies can be categorized into tissue-acquiring and non-tissue-acquiring modalities. Visible lesions in the setting of dysplasia should be treated with a tissue-acquiring modality to stage and resect the lesion appropriately. One or more modalities may be used to eradicate the entire region of affected esophagus totally. Total eradication treats all of the at-risk epithelium and, therefore, treats any metachronous or synchronous lesions. Success of treatment may be gauged by complete remission of cancer, dysplasia, or Barrett esophagus. In addition to procedure-related complications, the risk of residual Barrett esophagus or subsquamous Barrett esophagus remains to be addressed. Endoscopic surveillance and acid suppression is still currently required after ablation.

A cost-utility analysis of ablative therapy for Barrett's esophagus

BACKGROUND & AIMS

Recommendations for patients with Barrett's esophagus (BE) include endoscopic surveillance with esophagectomy for early-stage cancer, although new technologies to ablate dysplasia and metaplasia are available. This study compares the cost utility of ablation with that of endoscopic surveillance strategies.

METHODS

A decision analysis model was created to examine a population of patients with BE (mean age 50), with separate analyses for patients with no dysplasia, low-grade dysplasia (LGD), or high-grade dysplasia (HGD). Strategies compared were no endoscopic surveillance; endoscopic surveillance with ablation for incident dysplasia; immediate ablation followed by endoscopic surveillance in all patients or limited to patients in whom metaplasia persisted; and esophagectomy. Ablation modalities modeled included radiofrequency, argon plasma coagulation, multipolar electrocoagulation, and photodynamic therapy.

RESULTS

Endoscopic ablation for patients with HGD could increase life expectancy by 3 quality-adjusted years at an incremental cost of <$6,000 compared with no intervention. Patients with LGD or no dysplasia can also be optimally managed with ablation, but continued surveillance after eradication of metaplasia is expensive. If ablation permanently eradicates >or=28% of LGD or 40% of nondysplastic metaplasia, ablation would be preferred to surveillance.

CONCLUSIONS

Endoscopic ablation could be the preferred strategy for managing patients with BE with HGD. Ablation might also be preferred in subjects with LGD or no dysplasia, but the cost effectiveness depends on the long-term effectiveness of ablation and whether surveillance endoscopy can be discontinued after successful ablation. As further postablation data become available, the optimal management strategy will be clarified.

Treatment of Barrett's esophagus with high-grade dysplasia

The incidence of esophageal adenocarcinoma is increasing in the USA, now accounting for at least 4% of US cancer-related deaths. Barrett's esophagus is the main risk factor for the development of esophageal adenocarcinoma. The annual incidence of development of adenocarcinoma in Barrett's esophagus is approximately 0.5% per year, representing at least a 30-40-fold increase in risk from the general population. High-grade dysplasia is known to be the most important risk factor for progression to adenocarcinoma. Traditionally, esophagectomy has been the standard treatment for Barrett's esophagus with high-grade dysplasia. This practice is supported by studies revealing unexpected adenocarcinoma in 29-50% of esophageal resection specimens for high-grade dysplasia. In addition, esophagectomy employed prior to tumor invasion of the muscularis mucosa results in 5-year survival rates in excess of 80%. Although esophagectomy can result in improved survival rates for early-stage cancer, it is accompanied by significant morbidity and mortality. Recently, more accurate methods of surveillance and advances in endoscopic therapies have allowed scientists and clinicians to develop treatment strategies with lower morbidity for high-grade dysplasia. Early data suggests that carefully selected patients with high-grade dysplasia can be managed safely with endoscopic therapy, with outcomes comparable to surgery, but with less morbidity. This is an especially attractive approach for patients that either cannot tolerate or decline surgical esophagectomy. For patients that are surgical candidates, high-volume centers have demonstrated improved morbidity and mortality rates for esophagectomy. The addition of laparoscopic esophagectomy adds a less invasive surgical resection to the treatment armanentarium. Esophagectomy will remain the gold-standard treatment of Barrett's esophagus with high-grade dysplasia until clinical research validates the role of endoscopic therapies. Current treatment strategies for Barrett's esophagus with high-grade dysplasia will be reviewed.

Surgery versus radical endotherapies for early cancer and high grade dysplasia in Barrett's oesophagus

BACKGROUND

Barrett's oesophagus is one of the most common premalignant lesions in the world. Currently the mainstay of therapy is surgical management of advanced cancer but this has improved the five-year survival very little in the last 30 years. As a consequence, improved survival relies on early detection through endoscopic surveillance programmes. Success of this strategy relies on the fact that late stage premalignant lesions or very early cancers can be cured by intervention. Currently there is considerable controversy over which method is best: i.e. conventional open surgery or endotherapy (techniques involving endoscopy).

OBJECTIVES

We used data from randomised controlled trials to examine the effectiveness of endotherapies compared with surgery, in people with Barrett's Oesophagus; those with early neoplasias (defined as high grade dysplasia (HGD), and those with early cancer (defined as carcinoma in-situ, superficially invasive, early cancer or superficial cancer T-1m (T1-a) and T-1sm (T1-b)).

SEARCH STRATEGY

We used the Cochrane highly sensitive search strategy to identify randomized trials in MEDLINE, EMBASE, CENTRAL, ISI Web of Science, EBMR, Controlled Trials mRCT and ISRCTN and LILACS, in July and August 2008.

SELECTION CRITERIA

Types of studies: randomised controlled trials comparing endotherapies with surgery in the treatment of high grade dysplasia (HGD), or early cancer. All cellular types of cancer were included (i.e. adenocarcinomas, squamous cell carcinomas and more unusual types) but will be discussed separately.

TYPES OF PARTICIPANTS

patients of any age and either gender with a histologically confirmed diagnosis of early neoplasia (HGD and early cancer) in Barrett's or squamous lined oesophagus.Types of interventions; endotherapies (the intervention) compared with surgery (the control), all with curative intent.

DATA COLLECTION AND ANALYSIS

Reports of studies which meet the inclusion criteria for this review would have been analysed using the methods detailed in Appendix 9.

MAIN RESULTS

We did not identify any studies which met the inclusion criteria.

AUTHORS' CONCLUSIONS

This Cochrane review has indicated that there are no randomised control trials to compare management options in this vital area, therefore trials should be undertaken as a matter of urgency. The problems with such randomised methods are standardising surgery and endotherapies in all sites; standardising histopathology in all centres; assessing which patients are fit or unfit for surgery; and making sure there are relevant outcomes for the study i.e. no progression of high grade dysplasia or long term survival i.e. over five years.

Novel endoscopic therapeutic modalities for superficial neoplasms arising in Barrett's esophagus: a primer for surgical pathologists

This review introduces some of the novel endoscopic modalities used for the treatment of superficial neoplasms arising in the setting of Barrett's esophagus, namely endoscopic mucosal resection and photodynamic therapy. We describe the appropriate technical details for pathologists to know to effectively communicate with the gastroenterologists as well as the pitfalls in the evaluation of endoscopic mucosal resection specimens and post photodynamic therapy follow-up biopsies.

Barrett's oesophagus

Barrett's oesophagus is a metaplastic change of the lining of the oesophagus, such that the normal squamous epithelium is replaced by specialised or intestinalised columnar epithelium. The disorder seems to be a complication of chronic gastro-oesophageal reflux disease, although asymptomatic individuals might also be affected, and it is a risk factor for the development of oesophageal adenocarcinoma, a cancer with rapidly increasing incidence in developed societies. We review the presentation, epidemiology, and risk factors for this condition. We discuss the molecular changes necessary for the development of Barrett's oesophagus and its progression to cancer, and new strides in both the endoscopic detection of the lesion and the treatment of dysplastic disease. Also, we assess the effectiveness of efforts to screen patients at risk of Barrett's oesophagus, and whether such efforts avert cancer death. We conclude with a discussion of future directions for research, focusing on treatment of early neoplasia, and modifications of current practices to show our evolving understanding of this condition.

Squamous overgrowth is not a safety concern for photodynamic therapy for Barrett's esophagus with high-grade dysplasia

BACKGROUND & AIMS

Photodynamic therapy with porfimer sodium combined with acid suppression (PHOPDT) is used to treat patients with Barrett's esophagus (BE) with high-grade dysplasia (HGD). A 5-year phase 3 trial was conducted to determine the extent of squamous overgrowth of BE with HGD after PHOPDT.

METHODS

Squamous overgrowth was compared in patients with BE with HGD randomly assigned (2:1) to receive PHOPDT (n=138) or 20 mg omeprazole twice daily (n=70). Patients underwent 4-quadrant jumbo esophageal biopsies every 2 cm throughout the pretreatment length of BE until 4 consecutive quarterly follow-up results were negative for HGD and then biannually up to 5 years or treatment failure. Endoscopies were reviewed by blinded gastroenterology pathologists.

RESULTS

Histologic assessment of 33,658 biopsies showed no significant difference (P> .05) in squamous overgrowth between groups when compared per patient (30% vs 33%) or per biopsy (0.5% vs 1.3%), or when the average number of biopsies with squamous overgrowth were compared per patient (0.48 vs 0.66). The highest grade of neoplasia per endoscopy was not found exclusively beneath squamous mucosa in any patient.

CONCLUSIONS

No difference was observed in squamous overgrowth between patients given PHOPDT plus omeprazole compared with only omeprazole. Squamous overgrowth did not obscure the most advanced neoplasia in any patient. Treatment of HGD with PHOPDT in patients with BE does not present a long-term risk of failure to detect subsquamous dysplasia or carcinoma.

Update on the diagnosis and treatment of Barrett esophagus and related neoplastic precursor lesions

CONTEXT

At present, Barrett esophagus is the most common cause of esophageal adenocarcinoma. In the past 20 years, the incidence of esophageal adenocarcinoma in white males has exceeded that of tumors of the colorectum, lung, prostate, and skin.

OBJECTIVES

To (1) provide an evidence-based review of the diagnosis, classification, and histologic differentiation of Barrett esophagus from gastric carditis, (2) provide a summary of the key pathologic features of precursor lesions, such as dysplasia, and (3) evaluate adjunctive markers of dysplasia and predictive markers for the development of cancer. The natural history and risk of cancer in patients with Barrett esophagus is also reviewed.

DATA SOURCES

For this review, selected published peer reviewed articles were chosen from a search through PubMed between the years 1970 and 2007.

CONCLUSIONS

The current definition of Barrett esophagus is partially flawed because not all cases are endoscopically recognizable, nongoblet epithelium is biologically intestinalized, and determination of the presence or absence of goblet cells is susceptible to sampling error. Differentiation of ultrashort segment Barrett esophagus from chronic gastric carditis can be accomplished, in a minority of cases, by evaluating for the presence or absence of histologic features that are known to be associated with Barrett esophagus. Dysplasia in Barrett esophagus begins in the crypt bases and then extends more superficially to include the upper portions of the crypts and surface epithelium. Low- and high-grade dysplasia are distinguished by the presence of marked cytologic and/or architectural abnormalities in the latter compared with the former. There are few, if any, reliable adjunctive diagnostic techniques that can help differentiate nondysplastic from dysplastic epithelium. However, alpha-methylacyl coenzyme A racemase staining has been shown to be useful in 2 separate studies. Both low- and high-grade dysplasia are progressive lesions, and in general, the extent of dysplasia, particularly low grade, is a strong risk factor for progression to carcinoma. Of all the biologic and genetic biomarkers studied to date, evaluation of DNA content is the most reliable and specific. The management of patients with dysplasia is variable among institutions and ranges from aggressive surveillance, endoscopic mucosal resection, mucosal ablation, or total esophagectomy.

Correlation of histology with biomarker status after photodynamic therapy in Barrett esophagus

BACKGROUND

Currently, histology is used as the endpoint to define success with photodynamic therapy (PDT) in patients with high-grade dysplasia (HGD). Recurrences despite 'successful' ablation are common. The role of biomarkers in assessing response to PDT remains undefined. The objectives of the current study were 1) to assess biomarkers in a prospective cohort of patients with HGD/mucosal cancer before and after PDT and 2) to correlate biomarker status after PDT with histology.

METHODS

Patients who underwent PDT for HGD/mucosal cancer were studied prospectively. All patients underwent esophagogastroduodenoscopy, 4-quadrant biopsies every centimeter, endoscopic mucosal resection of visible nodules, and endoscopic ultrasound. Cytology samples were obtained by using standard cytology brushes. Biomarkers were assessed by using fluorescence in situ hybridization (FISH). The biomarkers that were assessed included loss of 9p21 (site of the p16 gene) and 17p13.1 (site of the p53 gene) loci; gains of the 8q24(c-myc), 17q (HER2-neu), and 20q13 loci; and multiple gains. Patients received PDT 48 hours after the administration of sodium porfimer. Demographic and clinical variables were collected prospectively. Patients were followed with endoscopy and repeat cytology for biomarkers. The McNemar test was used to compare biomarker proportions before and after PDT.

RESULTS

Thirty-one patients were studied. The median patient age was 66 years (interquartile range [IQR], 56-73 years), and 28 patients (88%) were men. The mean Barrett segment length was 5 cm (standard error of the mean, 0.5 cm). Post-PDT biomarkers were obtained after a median duration of 9 months (IQR, 3-12 months). There was a statistically significant decrease in the proportion of several biomarkers assessed after PDT. Six patients without HGD after PDT still had positive FISH results for 1 or more biomarkers: of these, 2 patients (33%) developed recurrent HGD.

CONCLUSIONS

In this initial study, histologic downgrading of dysplasia after PDT was associated with the loss of biomarkers that have been associated with progression of neoplasia in Barrett esophagus. Patients with persistently positive biomarkers appeared to be at a higher risk of recurrent HGD. These findings should be confirmed in a larger study.

Utility of biomarkers in prediction of response to ablative therapy in Barrett's esophagus

BACKGROUND & AIMS

Photodynamic therapy (PDT) has been shown to be effective in the treatment of high-grade dysplasia (HGD)/mucosal carcinoma in Barrett's esophagus (BE). Substantial proportions of patients do not respond to PDT or progress to carcinoma despite PDT. The role of biomarkers in predicting response to PDT is unknown. We aimed to determine if biomarkers known to be associated with neoplasia in BE can predict loss of dysplasia in patients treated with ablative therapy for HGD/intramucosal cancer.

METHODS

Patients with BE and HGD/intramucosal cancer were studied prospectively from 2002 to 2006. Biomarkers were assessed using fluorescence in situ hybridization performed on cytology specimens, for region-specific and centromeric probes. Patients were treated with PDT using cylindric diffusing fibers (wavelength, 630 nm; energy, 200 J/cm fiber). Univariate and multiple variable logistic regression was performed to determine predictors of response to PDT.

RESULTS

A total of 126 consecutive patients (71 who underwent PDT and 55 patients who did not undergo PDT and were under surveillance, to adjust for the natural history of HGD), were included in this study. Fifty (40%) patients were responders (no dysplasia or carcinoma) at 3 months after PDT. On multiple variable analysis, P16 allelic loss (odds ratio [OR], 0.32; 95% confidence interval [CI], 0.10-0.96) predicted decreased response to PDT. BE segment length (OR, 0.71; 95% CI, 0.59-0.85), and performance of PDT (OR, 7.17; 95% CI, 2.50-20.53) were other independent predictors of loss of dysplasia.

CONCLUSIONS

p16 loss detected by fluorescence in situ hybridization can help predict loss of dysplasia in patients with BE and HGD/mucosal cancer. Biomarkers may help in the selection of appropriate therapy for patients and improve treatment outcomes.

Should patients with Barrett's oesophagus be kept under surveillance? The case for

Oesophageal adenocarcinoma is associated with high mortality rates and its incidence is increasing more rapidly than any other gastrointestinal cancer in the Western world. Several factors, including gastro-oesophageal reflux disease, smoking, alcohol and male gender, are associated with oesophageal adenocarcinoma but none can be used to identify accurately those individuals who will develop adenocarcinoma. It is generally accepted that oesophageal adenocarcinoma arises predominantly in Barrett's oesophagus and it is arguable that Barrett's oesophagus is currently the only clinically useful predictor of oesophageal adenocarcinoma. Surveillance - periodic testing to detect adenocarcinoma or its precursor, high grade dysplasia - is widely recommended for patients with Barrett's oesophagus with the aim of reducing mortality from oesophageal adenocarcinoma. The annual incidence of oesophageal adenocarcinoma in patients with Barrett's oesophagus is 0.5%-1.0% although there is marked variation between studies, attributable variously to publication bias, concurrent acid suppression therapy and differences in patient characteristics. There is limited evidence that surveillance reduces the incidence of oesophageal adenocarcinoma or consequent mortality and the cause of death for patients undergoing surveillance is often unrelated to oesophageal disease. There are, nonetheless, observational studies which suggest that surveillance is associated with earlier detection of malignancy and a reduction in mortality; in addition, data from modelling studies suggest that surveillance can be cost-effective. Furthermore, the advent of new, non-surgical treatments (endoscopic mucosal resection, photodynamic therapy, argon plasma coagulation) for high grade dysplasia and early cancer has reduced the risks associated with therapy for disease detected during surveillance. Surveillance programs have high drop out rates and, for patients who continue surveillance, adherence to standard, published protocols is highly variable. The establishment of specialist Barrett's oesophagus surveillance programs, with coordinator support, has considerable potential to improve adherence to current guidelines, pending the acquisition and publication of data from ongoing studies of chemoprophylaxis and surveillance in the management of Barrett's oesophagus. In consequence, although there is a paucity of data providing unequivocal demonstration of benefit, there is no proof that surveillance is ineffective. It is, therefore, appropriate to offer surveillance for Barrett's oesophagus in accordance with locally-applicable published guidelines after a full informed discussion of the risks and benefits of surveillance and therapy; continued participation should be reviewed regularly to accommodate changes in the patient's health and expectations.

Endoscopic approaches to Barrett's oesophagus with high-grade dysplasia/early mucosal cancer

This chapter will review the endoscopic approaches to the management of Barrett's oesophagus with high-grade dysplasia/early mucosal cancer. Factors to consider when evaluating patients for endoscopic management are detailed. Ablation and resection methods for eradication of Barrett's oesophagus with high-grade dysplasia/early mucosal cancer are reviewed. Strategies for combining therapies to achieve safe and effective eradication are discussed. Recommendations for complete eradication of all Barrett's mucosa and follow-up considerations are put forward.

Endoscopic mucosal resection in the upper gastrointestinal tract

Endoscopic mucosal resection (EMR) is a technique used to locally excise lesions confined to the mucosa. Its main role is the treatment of advanced dysplasia and early gastrointestinal cancers. EMR was originally described as a therapy for early gastric cancer. Recently its use has expanded as a therapeutic option for ampullary masses, colorectal cancer, and large colorectal polyps. In the Western world, the predominant indication for EMR in the upper gastrointestinal tract is the staging and treatment of advance dysplasia and early neoplasia in Barrett’s esophagus. This review will describe the basis, indications, techniques, and complications of EMR, and its role in the management of Barrett’s esophagus.

Meta analysis: Cancer risk in Barrett's oesophagus

BACKGROUND

Risk of cancer in Barrett's oesophagus is reported to vary between studies and also between countries, where the studies were conducted as per several systematic reviews. Cancer incidence has implications on surveillance strategies.

AIM

To perform a meta-analysis to determine the incidence of oesophageal cancer in Barrett's oesophagus.

METHODS

Articles retrieved by MEDLINE search (English language, 1966-2004). Studies had to necessarily include verified Barrett's oesophagus surveillance patients, documented follow-up and cancer identified as the outcome measure. A random effects model of meta-analysis was chosen and results were expressed as mean (95% CI).

RESULTS

Forty-one articles selected for conventional Barrett's oesophagus (length >3 cm); eight included short segment Barrett's oesophagus (one additional article including only short segment Barrett's oesophagus). Cancer incidence was 7/1000 (6-9) person-years duration of follow-up (pyd), with no detectable geographical variation [UK 7/1000 (4-12) pyd, USA 7/1000 (5-9) pyd and Europe 8/1000 (5-12) pyd]. Cancer incidence in the UK was 10/1000 (7-14), when two large studies were excluded. Cancer incidence in SSBO was 6/1000 (3-12) pyd. When short segment Barrett's oesophagus compared to conventional Barrett's oesophagus, there was a trend towards reduced cancer risk [OR 0.55, (95% CI: 0.19-1.6), P = 0.25].

CONCLUSION

We found no geographical variations in Barrett's oesophagus cancer risk, but observed a trend towards reduced cancer risk in short segment Barrett's oesophagus. There is a time trend of decreasing cancer incidence.

Five-year efficacy and safety of photodynamic therapy with Photofrin in Barrett's high-grade dysplasia

BACKGROUND

Barrett's esophagus (BE) with high-grade dysplasia (HGD) is a risk factor for development of esophageal carcinoma. Photodynamic therapy (PDT) with Photofrin (PHO) has been used to eliminate HGD in BE.

OBJECTIVE

Our purpose was to compare PHOPDT plus omeprazole with omeprazole only (OM).

DESIGN

Five-year follow-up of a randomized, multicenter, multinational, pathology-blinded HGD trial.

SETTING

30 sites in 4 countries.

PATIENTS

208.

INTERVENTIONS

Patients with BE and HGD were randomized (2:1) to PHOPDT (n=138) or OM (n=70) into a 2-year trial followed up for 3 more years. PHOPDT patients received 2 mg/kg PHO intravenously followed by endoscopic laser light exposure of Barrett's mucosa at a wavelength of 630 nm within 40 to 50 hours to a maximum of 3 courses at least 90 days apart. Both groups received 20 mg of OM twice daily. Pathologists at one center assessed biopsy specimens in a blinded fashion.

MAIN OUTCOME MEASUREMENT

HGD ablation status over 5 years of follow-up.

RESULTS

At 5 years PHOPDT was significantly more effective than OM in eliminating HGD (77% [106/138] vs 39% [27/70], P<.0001). A secondary outcome measure preventing progression to cancer showed a significant difference (P=.027) with about half the likelihood of cancer occurring in PHOPDT (21/138 [15%]) compared with OM (20/70 [29%]), with a significantly (P=.004) longer time to progression to cancer favoring PHOPDT.

LIMITATIONS

Not all patients were available for follow-up.

CONCLUSIONS

This 5-year randomized trial of BE patients with HGD demonstrates that PHOPDT is a clinically and statistically effective therapy in producing long-term ablation of HGD and reducing the potential impact of cancer compared with OM.