Histopathologic aspects of photodynamic therapy for dysplasia and early adenocarcinoma arising in Barrett's esophagus

Post-ablation buried neoplasia in Barrett's esophagus

Endoscopic eradication therapy (EET) with maximal acid suppression is the cornerstone for the management of patients with Barrett's esophagus (BE) associated dysplasia. The occurrence of buried dysplastic glands after re-epithelialization of a neo-squamous epithelium is of concern for endoscopists. Here, we present a patient with BE and high-grade dysplasia successfully treated by EET who developed buried dysplastic BE during surveillance. A review of literature on buried dysplasia after successful endoscopic therapy of BE is also discussed.

Endoscopic treatments for dysplastic Barrett's esophagus: resection, ablation, what else?

BACKGROUND

Endoscopic eradication therapy for dysplastic Barrett's esophagus (BE) comprises resection and mucosal ablation techniques. Over the years, these techniques have been tried with success, not only for dysplastic Barrett's epithelium but also for non-dysplastic Barrett's epithelium and early adenocarcinoma. Endoscopic resection is usually carried out for visible lesions, either as endoscopic mucosal resection (EMR), which is practiced widely in Western countries, or as endoscopic submucosal dissection, which is more popular in Japan and throughout Asia. Among ablative techniques are photodynamic therapy, cryotherapy, and radiofrequency ablation (RFA).

METHODS

We reviewed the published evidence pertaining to endoscopic treatments of dysplastic BE, with emphasis on the various resection and ablative techniques, their safety, efficacy, durability of effect, and tolerability.

RESULTS

Both resection and ablation procedures performed endoscopically have been proved effective, and safe for treating dysplastic BE and early adenocarcinoma. Among the ablative techniques, RFA has shown to be more effective and safe, and is preferred for most cases.

CONCLUSIONS

Endoscopic therapies have revolutionized the treatment of BE and have minimized the need for surgical intervention in many patients. Concomitant treatment of acid reflux with proton pump inhibitors and continuous surveillance are essential. Combination techniques such as EMR followed by RFA may be also considered in some cases.

Limitations of endoscopic ablation in Barrett's esophagus

In the last 5-10 years, endoscopic ablative therapies have been gaining ground as treatment for Barrett's esophagus associated with high-grade dysplasia and early cancer, and they are becoming the most preferred technique over surgery as the standard of care. These therapies are associated with a lower rate of complications and mortality than surgery; studies have found them to be safe, effective and tolerable. Endoscopic ablative therapies are not, however, without their drawbacks. There is a paucity of data on long-term efficacy, and direct comparisons of the different modalities are lacking. Unlike surgery, current data suggest that endoscopic ablation treatments may not be curative in all patients, so patients require ongoing surveillance and acid suppression. Questions remain regarding durability as well as factors promoting recurrence after endoscopic therapy. The authors conducted a systematic review of the literature on ablative therapies in Barrett's esophagus to describe the modalities currently available and to provide an understanding of their limitations.

Sixteen-year follow-up of Barrett's esophagus, endoscopically treated with argon plasma coagulation

OBJECTIVE

The thermal destruction of non-dysplastic Barrett's esophagus (BE) and its replacement by squamous epithelium is an attractive, but unproven strategy to avoid further development of dysplasia or cancer. The goal of this study was to estimate the persistence of restoration of squamous epithelium and the risk of cancer in BE that was eradicated using argon plasma coagulation (APC) in the absence of high-grade dysplasia, 16 years after its application.

DESIGN

We followed 32 patients with BE who underwent eradication of metaplastic epithelium using APC, up to 16 years later.

RESULTS

At the end of the initial treatment, 25 of 32 patients (78%) had complete endoscopic eradication, there was partial squamous re-epithelialization in four patients (13%) and it was absent in three patients (9%). We observed buried metaplastic glands under new squamous epithelium in 6 of the 25 patients who had complete endoscopic eradication. At follow-up, sustained complete endoscopic eradication was observed in 16 of 32 patients (50%), partial eradication in 11 of 32 patients (35%); there were two patients (6%) lost to follow-up and three patients (9%) developed esophageal adenocarcinoma. Two of the latest cases arose from the buried glands under neosquamous epithelium after complete eradication and one arose from a small remaining Barrett's segment.

CONCLUSIONS

We observed long-term re-epithelialization in the majority of patients who had previously had complete eradication of Barrett's esophagus. This did not provide protection against cancer development, as the incidence of cancers arising from buried glands or from residual Barrett's esophagus was similar to that observed in patients undergoing no specific treatment.

Strategies to improve outcomes in esophageal adenocarcinoma

Esophageal adenocarcinoma is one of the fastest rising cancers in Western society. Incidence has increased by 600% within the last 30 years. Rates of diagnosis and death run parallel due to the poor prognosis and a lack of effective treatments. Potentially curative treatments are followed by high rates of disease recurrence. For the majority of patients, who present with advanced disease, we have no effective treatment. We discuss the key areas of progress in this demanding field and offer our views on the direction of future research and treatment.

Subsquamous intestinal metaplasia after ablation of Barrett's esophagus: frequency and importance

PURPOSE OF REVIEW

This article reviews reports on the prevalence of subsquamous intestinal metaplasia (SSIM) in patients with Barrett's esophagus, and the implications of SSIM in the neoplastic progression of Barrett's esophagus to esophageal adenocarcinoma.

RECENT FINDINGS

Endoscopic eradication therapy for dysplastic Barrett's esophagus has become an encouraging alternative to esophagectomy or continued endoscopic surveillance. However, the presence of SSIM before and after ablation is concerning because this tissue may have potential for malignant progression, is not visible by conventional endoscopy, and may evade detection by random esophageal biopsy sampling methods. Advances in endoscopic high-resolution three-dimensional optical coherence tomography recently have revealed SSIM in a majority of patients both before and after complete eradication of Barrett's esophagus by radiofrequency ablation. Studies suggest that although cells of Barrett's glands are highly proliferative, the cells of these buried glands are more dormant. Nevertheless, the malignant potential of SSIM cells remains undetermined.

SUMMARY

Novel endoscopic imaging demonstrates that SSIM is present in the majority of patients with Barrett's esophagus, both before and after ablative therapy. Although these subsquamous cells exhibit less proliferative activity than those of typical surface Barrett's glands, the malignant potential of the buried glands, especially when challenged by injurious factors, remains largely unknown. Future methods to detect subsurface dysplasia will be needed.

Barrett's esophagus: review of diagnosis and treatment

Barrett's esophagus (BE) is an acquired condition characterized by replacement of stratified squamous epithelium by a cancer predisposing metaplastic columnar epithelium. Endoscopy with systemic biopsy protocols plays a vital role in diagnosis. Technological advancements in dysplasia detection improves outcomes in surveillance and treatment of patients with BE and dysplasia. These advances in endoscopic technology radically changed the treatment for dysplastic BE and early cancer from being surgical to organ-sparing endoscopic therapy. A multimodal treatment approach combining endoscopic resection of visible and/or raised lesions with ablation techniques for flat BE mucosa, followed by long-term surveillance improves the outcomes of BE. Safe and effective endoscopic treatment can be either tissue acquiring as in endoscopic mucosal resection and endoscopic submucosal dissection or tissue ablative as with photodynamic therapy, radiofrequency ablation and cryotherapy. Debatable issues such as durability of response, recognition and management of sub-squamous BE and optimal management strategy in patients with low-grade dysplasia and non-dysplastic BE need to be studied further. Development of safer wide field resection techniques, which would effectively remove all BE and obviate the need for long-term surveillance, is another research goal. Shared decision making between the patient and physician is important while considering treatment for dysplasia in BE.

Esophageal squamous cell carcinoma with special reference to its early stage

The term 'early squamous cell carcinoma of the oesophagus', which was previously restricted to superficial carcinoma with no lymph node metastasis, now encompasses intramucosal carcinoma regardless of the nodal status. Such lesions are rare in Western countries, where the experience is limited. In recent years, the development and greater use of chromoendoscopy and narrow band imaging (NBI), both of which facilitate the evaluation of mucosal morphology, have played an important role in the detection of early esophageal squamous cell carcinoma. In addition, the techniques and indications of endoscopic resection (mucosal resection [EMR] and mucosal dissection [ESD]) are still being refined. In the present article, we will discuss the clinical and pathologic features of esophageal early squamous cell carcinoma, as well as the epidemiology and aetiology of esophageal cancer in general. In addition, we will provide a therapeutic decision tree taking into account endoscopic and surgical modalities as they apply to early esophageal squamous cell carcinoma.

Management strategies of Barrett's esophagus

Barrett’s esophagus is a condition resulting from chronic gastro-esophageal reflux disease with a documented risk of esophageal adenocarcinoma. Current strategies for improved survival in patients with Barrett's adenocarcinoma focus on detection of dysplasia. This can be obtained by screening programs in high-risk cohorts of patients and/or endoscopic biopsy surveillance of patients with known Barrett’s esophagus (BE). Several therapies have been developed in attempts to reverse BE and reduce cancer risk. Aggressive medical management of acid reflux, lifestyle modifications, antireflux surgery, and endoscopic treatments have been recommended for many patients with BE. Whether these interventions are cost-effective or reduce mortality from esophageal cancer remains controversial. Current treatment requires combinations of endoscopic mucosal resection techniques to eliminate visible lesions followed by ablation of residual metaplastic tissue. Esophagectomy is currently indicated in multifocal high-grade neoplasia or mucosal Barrett’s carcinoma which cannot be managed by endoscopic approach.

Radiofrequency ablation associated to mucosal resection in the oesophagus: experience in a single centre

Endoscopic resection (EMR) and radiofrequency ablation (RFA) form part of the treatment of Barrett's oesophagus (BO), dysplasia, superficial adenocarcinoma (OAC) associated with BO.

PATIENTS AND METHODS

Between June 2008 and April 2011, 34 patients underwent treatment with RFA (HALO system(®)), in a tertiary centre. For the study, patients were divided into two groups. Group 1 (16 patients of average 60 years old; 14 men, two women) received EMR and RFA. Group 2 (18 patients averaging 59 years age; 14 men, four women) received RFA without EMR in the year preceding the RFA.

RESULTS

In group 1, high grade dysplasia (HGD) was eradicated in 12 cases (92%), low grade dysplasia (LGD) in three cases (100%). Complete response occurred in nine cases (56%), partial response in 100% of cases. Mean follow-up was 15 months. In group 2, HGD was eradicated in one patient (100%), LGD in three patients (64%). A complete response was achieved in eight patients, partial response in four cases (77%). Mean follow-up was 10 months. The complication rate for groups 1 and 2 was of 18% and 10% respectively. No complication prevented completion of treatment or continued monitoring. Recurrence was evaluated to 5% in both groups.

CONCLUSION

RFA associated with EMR is feasible, offering probably better results and a very important advantage: a more complete histology before follow-up. Our results show effective treatment of BO and associated dysplasia with a low rate of complication. Nevertheless, when new techniques of BO ablation are used, the need to obtain histology before treatment should not be forgotten.

Endoscopic therapy for Barrett's esophagus: a review of its emerging role in optimal diagnosis and endoluminal therapy

Barrett's esophagus (BE) is a premalignant lesion known to sequentially progress to esophageal adenocarcinoma. Management of BE has changed significantly over the last 5 years with the development of endoscopic resection and ablation, which has replaced esophagectomy as the treatment of choice in BE with high-grade dysplasia. The aim of this review is to discuss the details of these new endotherapies in regards to response and durability and to define the role of these new therapies in the current management of BE.

Buried metaplasia after endoscopic ablation of Barrett's esophagus: a systematic review

OBJECTIVES

Endoscopic ablation of Barrett's esophagus can bury metaplastic glands under a layer of neosquamous epithelium. To explore the frequency and importance of buried metaplasia, we have conducted a systematic review of reports on endoscopic ablation.

METHODS

We performed computerized and manual searches for articles on the results of photodynamic therapy (PDT) and radiofrequency ablation (RFA) for Barrett's esophagus. We extracted information on the number of patients treated, biopsy protocol, biopsy depth, and frequency of buried metaplasia.

RESULTS

We found 9 articles describing 34 patients with neoplasia appearing in buried metaplasia (31 after PDT). We found five articles describing a baseline prevalence of buried metaplasia (before ablation) ranging from 0% to 28%. In 22 reports on PDT for 953 patients, buried metaplasia was found in 135 (14.2%); in 18 reports on RFA for 1,004 patients, buried metaplasia was found in only 9 (0.9%). A major problem limiting the conclusions that can be drawn from these reports is that they do not describe specifically how frequently biopsy specimens contained sufficient subepithelial lamina propria to be informative for buried metaplasia.

CONCLUSIONS

Endoscopic ablation can bury metaplastic glands with neoplastic potential but, even without ablation, buried metaplasia often is found in areas where Barrett's epithelium abuts squamous epithelium. Buried metaplasia is reported less frequently after RFA than after PDT. However, available reports do not provide crucial information on the adequacy of biopsy specimens and, therefore, the frequency and importance of buried metaplasia after endoscopic ablation remain unclear.

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.

Endoscopic management of Barrett esophagus

Endoscopy has a vital role in the diagnosis, screening, surveillance and treatment of Barrett esophagus. Over the past few decades, tremendous advances have been made in endoscopic technology, and the management of dysplasia and early cancer in Barrett esophagus has changed radically from being surgical to organ-sparing endoscopic therapy. Proper endoscopic techniques and systematic biopsy protocols improve dysplasia detection, and endoscopic surveillance improves outcomes in patients with Barrett esophagus and dysplasia. Endoscopic treatment can be tissue acquiring (as in endoscopic mucosal resection and endoscopic submucosal dissection) or ablative (as with photodynamic therapy, radiofrequency ablation and cryotherapy). Treatment is usually multimodal, combining endoscopic resection of visible lesions with one or more mucosal ablation techniques, followed by long-term surveillance. Such treatment is safe and effective. Shared decision-making between the patient and physician is important while considering treatment for dysplasia in Barrett esophagus. Issues such as durability of response, importance of subsquamous Barrett epithelium and the optimal management strategy in patients with low-grade dysplasia and nondysplastic Barrett esophagus need to be studied further. Development of safer wide-field resection techniques, which would effectively remove all Barrett esophagus and obviate the need for long-term surveillance, is needed.

The significance of "indefinite for dysplasia" grading in Barrett metaplasia

CONTEXT

For a confident diagnosis of dysplasia in Barrett metaplasia, the epithelial atypia should also involve the surface epithelium. However, pathologists are often faced with biopsies where the crypts show dysplasia, but the surface epithelium is either uninvolved or unevaluable. We previously grouped these cases with indefinite for dysplasia (IND).

OBJECTIVE

To determine the clinical significance of IND grading in Barrett metaplasia.

DESIGN

All biopsies from 276 prospectively followed patients with Barrett metaplasia, who did not have high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) on initial biopsy, were graded as negative for dysplasia, IND, low-grade dysplasia (LGD), HGD, and EAC. Biopsies with multifocal IND or LGD were graded as INDM or LGDM, respectively.

RESULTS

Only 3 of 193 patients (2%) with an initial diagnosis of negative for dysplasia and only 1 of 48 patients (2%) diagnosed with IND progressed to HGD or EAC. By contrast, 1 of 7 patients (14%) with INDM, 2 of 21 (10%) with LGD, and 1 of 7 (14%) with LGDM progressed to HGD or EAC. There was no significant difference in progression rate between patients with an initial diagnosis of negative for dysplasia and those diagnosed IND nor were there significant differences among patients with initial diagnoses of INDM, LGD, or LGDM. Kaplan-Meier analysis showed that patients with INDM, LGD, or LGDM on initial biopsy (group 1) were more likely to progress to HGD or EAC than were those patients who were diagnosed negative for dysplasia or IND (group 2; log-rank test, P < .001).

CONCLUSIONS

Multifocal IND in an esophageal biopsy from a patient with Barrett metaplasia has the same clinical implication as LGD.

Photodynamic therapy

Photodynamic therapy (PDT) is a photochemical process that uses a photosensitizer drug activated by laser light to produce mucosal ablation. Porfimer sodium PDT has proved long-term efficacy and durability in the treatment of Barrett's esophagus and high-grade dysplasia and early esophageal adenocarcinoma. Its use has been limited by serious side effects including prolonged cutaneous photosensitivity and stricture formation. Other photosensitizers with a better safety profile have been used mostly in Europe with limited experience. The future of PDT lies on a better understanding of dosimetry, tissue properties, and host genetic factors.

New endoscopic and surgical treatment options for early esophageal adenocarcinoma

Although the outcome for advanced stage esophageal cancer is poor, the early detection and treatment of early stage disease is usually associated with a much better outcome. Until recently, esophagectomy has been the treatment of choice in fit patients. However, morbidity is significant, and this has encouraged the development of newer endoscopic treatments that preserve the esophagus. These techniques include ablation and mucosal resection. Promising results are described, and endoscopic methods might provide a reasonable alternative for the treatment of early esophageal cancer. However, follow-up remains short and endoscopic treatment does not deal with potential lymphatic spread. Hence, careful selection is required. Minimally invasive techniques for esophageal resection have also been shown to be feasible, although there is only limited evidence that they reduce postoperative morbidity. Better data are still required to demonstrate improved outcomes from endoscopic treatment and minimally invasive esophagectomy.

New Endoscopic Techniques: Challenges and Opportunities for Surgical Pathologists

In recent years, significant clinical and technological advances have been made in endoscopic methods for diagnosis and treatment of early gastrointestinal neoplasms. However, essential information related to these novel techniques and their implications for practicing surgical pathologists have largely been missing in the general pathology literature. This article provides a general introduction to these novel therapeutic and diagnostic methods, and discusses their indications, contraindications, and potential limitations. The article aims to enable surgical pathologists to interact more efficiently with basic scientists and clinical colleagues to help implement and improve the existing clinical methods and to advance the new technologies.

Endoluminal therapy for esophageal disease: an introduction

This introductory article summarizes decades of research from many dedicated gastrointestinal endoscopists. It provides a background to Barrett esophagus (BE), exploring the risk of progression to dysplasia and esophageal adenocarcinoma. Two premalignant conditions, BE and colon adenoma, are compared, including their progression to esophageal adenocarcinoma and colon and rectal carcinoma, respectively. A comparison of the risks of surgical treatment and post-surgical complications of these cancers and of the strikingly different paradigms for their prevention is presented. The article concludes with the rationale for endoscopic treatment of Barrett disease.

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.

Squamous intraepithelial neoplasia of the esophagus: past, present, and future

With regard to the esophagus, the term "squamous dysplasia" has been used in European countries, the United States, and China, while its use is controversial in Japan. Recently, "low-grade intraepithelial neoplasia" and "high-grade intraepithelial neoplasia" have been used as inclusive terms for dysplasia and carcinoma in situ in the World Health Organization classification. Endoscopically, it is often difficult to identify squamous intraepithelial neoplasia by conventional endoscopy, but application of iodine is useful for the diagnosis of such a lesion. In addition, new types of endoscopic techniques, including magnifying endoscopy, narrow-band imaging (NBI), and endocytoscopy are helpful to detect squamous intraepithelial neoplasia. NBI is very useful for identifying the intrapapillary capillary loop pattern. Regarding the pathological criteria of squamous dysplasia and squamous cell carcinoma, the views of Japanese and Western pathologists have differed significantly. Before the term "intraepithelial neoplasia" was introduced, severe dysplasia as diagnosed by Western pathologists was in fact the same as squamous cell carcinoma in situ or noninvasive carcinoma as diagnosed by Japanese pathologists. This problem has been solved by the introduction of the Vienna classification; however, there are still some issues that need to be resolved. One of them is the presence of basal layer type squamous cell carcinoma in situ, which is often underdiagnosed as lowgrade intraepithelial neoplasia by Western pathologists. Endoscopic treatments such as endoscopic mucosal resection and endoscopic submucosal dissection have recently become possible choices for squamous intraepithelial neoplasia; however, these techniques are not in widespread use in the West. We believe that a consensus meeting between Japanese and Western pathologists as well as endoscopists should be held promptly to reach a common ground for the nomenclature.

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.

Patient predictors of histopathologic response after photodynamic therapy of Barrett's esophagus with high-grade dysplasia or intramucosal carcinoma

BACKGROUND

Photodynamic therapy (PDT) has been used extensively for endoscopic ablation of Barrett's esophagus with high-grade dysplasia (HGD) or intramucosal carcinoma.

OBJECTIVE

To identify patient variables that influence the likelihood of response to PDT.

DESIGN

A retrospective cohort study.

SETTING

Tertiary-referral center.

PATIENTS

A total of 116 patients with Barrett's esophagus and with HGD, intramucosal carcinoma, or T1 cancer.

INTERVENTIONS

PDT with porfimer sodium.

MAIN OUTCOME MEASUREMENTS

(1) Ablation of HGD and/or intramucosal carcinoma and (2) eradication of all Barrett's epithelium.

RESULTS

Of the patients, 51% underwent treatment for HGD and 49% of patients had intramucosal carcinoma or T1 cancer. At 12-month follow-up, ablation of HGD and/or cancer was observed in 70% of patients, and ablation of all Barrett's epithelium was observed in 39%. In multivariate analysis, the pretreatment length of Barrett's esophagus was inversely correlated with successful ablation of all Barrett's epithelium. Patients with Barrett's esophagus length more than 3 cm were less likely to experience complete ablation compared with patients with Barrett's esophagus length 3 cm or less (odds ratio [OR] 0.15 [95% CI, 0.04-0.50]). Patients with intramucosal carcinoma were not significantly less likely to experience elimination of HGD and/or cancer (OR 0.77 [95% CI, 0.30-2.00]) or ablation of all Barrett's epithelium (OR 0.82 [95% CI, 0.32-2.07]) compared with patients with HGD alone.

LIMITATIONS

Retrospective study, limited sample size without a control group for comparison.

CONCLUSIONS

PDT of Barrett's esophagus with HGD, intramucosal carcinoma, or T1 cancer can result in ablation of dysplasia and/or eradication of all Barrett's epithelium. Factors associated with the likelihood of response include length of Barrett's esophagus. The presence of intramucosal carcinoma or T1 cancer was not associated with higher likelihood of treatment failure.

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.

Barrett's esophagus

Barrett's esophagus is an important step in the pathway to esophageal adenocarcinoma. Since most patients with Barrett's esophagus are undiagnosed and patients present with advanced adenocarcinoma de novo, prognosis for this disease remains poor. To identify those people with Barrett's esophagus who are at particular risk many new technologies are being developed. In association with these advances in risk stratification, progress is being made in the endoscopic treatment of Barrett's. Chemoprevention is also an area of interest and trials are underway.

Photodynamic therapy using 5-aminolaevulinic acid for the treatment of dysplasia in Barrett's oesophagus

BACKGROUND

5-Aminolaevulinic acid (ALA) is the naturally occurring metabolic precursor of an endogenously formed photosensitiser, protoporphyrin IX. It is used topically to treat benign and malignant skin disorders by a process called photodynamic therapy (PDT). Recently, data are emerging on its systemic use in the treatment of dysplasia in Barrett's oesophagus.

OBJECTIVE

To investigate the use of ALA-PDT for the treatment of dysplasia and early cancer in Barrett's oesophagus.

METHODS

A systematic literature review and synopsis is given.

CONCLUSION

ALA is an attractive alternative to the currently approved photosensitiser (porfimer sodium) due to its oral route of administration, shorter generalised skin photosensitivity period and lower rate of stricture formation. The studies presented demonstrate that ALA-PDT is both safe and effective for the treatment of dysplasia and early cancer in Barrett's oesophagus.

Patient predictors of esophageal stricture development after photodynamic therapy

BACKGROUND & AIMS

The most common significant adverse event after photodynamic therapy (PDT) with porfimer sodium is esophageal stricture formation. This study assessed whether pretreatment variables, including prior endoscopic therapy for Barrett's esophagus, are associated with post-PDT stricturing.

METHODS

Data from all patients who had undergone PDT with porfimer sodium for Barrett's esophagus with high-grade dysplasia, intramucosal carcinoma, or T1 cancer at our institution since 1997 were reviewed.

RESULTS

One hundred sixteen patients underwent 160 courses of PDT. The incidence of stricture formation after index PDT was 16% (19/116). For all PDT courses, the overall incidence of stricture was 23% (37/160). Stricture rate was significantly higher after a second PDT course compared with index PDT (43% vs 16%, P = .0007). There was no association between post-PDT stricture development and age, gender, body mass index, or prior endoscopic mucosal resection. Patients who developed a stricture had a longer length of Barrett's esophagus before treatment than those who did not develop a stricture (7.7 vs 5.7 cm for index PDT only, P = .025; 7.4 vs 5.7 cm for all PDT courses, P = .007). Length of Barrett's esophagus, multiple PDT courses, and presence of intramucosal carcinoma on pretreatment pathology were independent predictors of post-PDT stricture in a stepwise logistic regression analysis controlling for treatment variables, including treatment length.

CONCLUSIONS

An increased risk of stricture development was seen after multiple courses of PDT. An association between post-PDT stricture and length of Barrett's esophagus but not treatment length was also found. Endoscopic mucosal resection did not appear to influence the likelihood of stricture development after porfimer sodium-based PDT.

Endoscopic ultrasound: accuracy in staging superficial carcinomas of the esophagus

BACKGROUND

Endoscopic procedures may represent an alternative to esophagectomy for superficial neoplasms of the esophagus (T1m/T1sm), but they are considered curative only in case of no lymph node involvement. Endoscopic ultrasound (EUS) is the most accurate method to define both T and N staging of esophageal carcinoma. Aims of the study were to assess the staging accuracy of EUS in superficial lesions (T1m and T1sm) of patients who were candidates for esophagectomy or local endoscopic resection and to establish which variables (site of neoplasm, histologic type, macroscopic appearance) can affect the accuracy of EUS in distinguishing between T1m and T1sm lesions.

METHODS

The study population consisted of 55 patients with superficial carcinoma of the esophagus who underwent EUS (October 2002 to January 2007). Endoscopic ultrasound features were compared with findings from surgical specimens or samples obtained at mucosectomy.

RESULTS

There were 33 patients with adenocarcinoma (60%), which developed on Barrett's esophagus in 27 cases, 21 patients (38%) with squamous cell carcinoma, and 1 (2%) with lymphoepithelial-like carcinoma. All lesions were confirmed as T1 on pathology. Of the 22 (40%) T1m lesions on EUS, 19 (86%) were confirmed as T1m on pathology; of the 33 T1sm on EUS, 22 (66%) were confirmed as T1sm. Positive predictive value of EUS for invasion of the submucosa was 67%, negative predictive value 86%, sensitivity 88%, specificity 63%, and diagnostic accuracy 75%. The accuracy of EUS in evaluating lymph node metastases was 71%, with a negative predictive value of 84%. Endoscopic ultrasound accuracy in differentiating mucosal from submucosal lesions increased from the lower esophagus or gastroesophageal junction to the mid and upper esophagus (71%, 76%, and 100%, respectively; not significant). As for the histologic type, accuracy was 70% for adenocarcinoma and 81% for squamous cell carcinoma, (not significant); for lesions detected as type 0-IIa (13 patients), accuracy was 100%; for type 0-I lesions (23 patients), accuracy was 70% (p = 0.03).

CONCLUSIONS

Despite difficulties in differentiating mucosal from submucosal lesions, even with 20-MHz miniprobes, EUS remains an extremely valuable tool when nonsurgical treatments are considered. Its staging accuracy depends on site and macroscopic appearance of the neoplasm.

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.

Banding without resection (endoscopic mucosal ligation) as a novel approach for the ablation of short-segment Barrett's epithelium: results of a pilot study

OBJECTIVES

During an endoscopic variceal ligation, we banded a varix with an overlying tongue of Barrett's epithelium (BE). One month later, the tongue was no longer visible, suggesting that banding could be used to eradicate BE.

AIM

To assess the safety and efficacy of banding without resection (BWR) using a variceal banding device for eradicating BE.

METHODS

From April 2004 through September 2005, 30 patients with BE were treated with BWR plus omeprazole 20 mg t.i.d. BWR was repeated monthly until two consecutive endoscopic and histological examinations showed no BE. Thirty Barrett's patients treated with omeprazole 20 mg t.i.d. alone served as a control group.

RESULTS

The BWR treatment group comprised 29 patients with short-segment BE (SSBE) and one with long-segment disease, whereas all 30 of the control patients had SSBE. During a median follow-up of 16.9 months (range 10-24 months), complete eradication of BE was achieved in 29 of 30 patients (97%) in the BWR group. In contrast, BE persisted in all 30 control patients during the same period (P < 0.0005). The mean total number of bands applied per patient was 6.1 (range 1-14) and the mean number of sessions for complete eradication was 3.1 (range 1-7). Adverse events included only mild chest pain and dysphagia that resolved within days.

CONCLUSIONS

BWR appears to be a safe, effective, simple, and widely available technique for eradicating SSBE. This is a pilot study and we do not recommend the ablation of nondysplastic BE at this time. Further studies are needed.

How light dosimetry influences the efficacy of photodynamic therapy with 5-aminolaevulinic acid for ablation of high-grade dysplasia in Barrett's esophagus

Photodynamic therapy (PDT) with 5-aminolaevulinic acid (ALA) is a novel treatment for high-grade dysplasia (HGD) in Barrett's esophagus (BE). Our aim was to evaluate the effectiveness of differing light doses. Patients with HGD in BE received oral ALA (60 mg/kg) activated by low (500 J/cm), medium (750 J/cm), high (1,000 J/cm), or highest (1,000 J/cm x2) light dose at 635 nm. Follow-up was by regular endoscopy with quadrantic biopsies. Twenty-four patients were treated. Successful eradication of HGD was significantly correlated with light dose (log rank, p < 0.01). Six of eight patients (75%) treated with the highest light dose, one of two treated with high dose (50%), two of nine (22%) receiving medium light dose, and zero of five receiving low light dose had successful eradication of HGD (median follow-up 45 months, range 1-78 months). No skin photosensitivity or esophageal strictures occurred. The efficacy of ALA-PDT for eradication of HGD in BE is closely related to the light dose used. With a drug dose of 60 mg/kg and light at 635 nm, we recommend a minimum light dose of 1,000 J/cm of esophagus. This dose appears safe.

Endoscopic therapy of dysplasia and early-stage cancers of the esophagus

Endoscopic treatments have become a viable alternative for some patients with early-stage esophageal neoplasia. Although esophagectomy remains the standard of care for high-grade dysplasia and superficial cancers, surgical morbidity and mortality may deter patients who are medically unfit or reluctant to undergo surgery. Photodynamic therapy (PDT) and endoscopic mucosal resection (EMR) are the best-studied nonsurgical approaches at present. PDT has been reported to eradicate high-grade dysplasia (HGD) and early Barrett's cancers at rates ranging from 75% to 100% and 17% to 100%, respectively, and a recent randomized controlled trial confirmed that PDT may prevent progression of HGD to cancer. Complete remission rates greater than 90% have also been reported with EMR and other mucosa-ablating interventions, although recurrence rates necessitate close endoscopic surveillance and retreatment in some patients. In addition to PDT and EMR, several emerging endoscopic treatment options for superficial esophageal neoplasia may provide attractive alternatives to surgery.

Buried Dysplasia and Early Adenocarcinoma Arising in Barrett Esophagus After Porfimer-photodynamic Therapy

The restoration of squamous epithelium after photodynamic therapy (PDT) for Barrett esophagus (BE) and its related neoplasms has been noted. It may result in the development of buried neoplasms and/or BE underneath restored squamous epithelium which maintain their potential for malignant transformation. The purpose of this study was to evaluate the prevalence, endoscopic, and histologic characteristics and also response to further treatment of buried neoplastic epithelium developing after PDT. Fifty-two BE patients with high-grade dysplasia (n=19), intramucosal adenocarcinoma (n=28), and invasive adenocarcinoma (n=5) were treated with porfimer PDT. Buried neoplasms completely covered by squamous epithelium were seen in 1 patient before and in 13 patients after PDT. Their prevalence was 0.6% and 7.4% of pre and post-PDT biopsy levels positive for neoplasia (P=0.001). Buried neoplasms, representing the highest grade of residual neoplasm, were noted in a series of 11 post-PDT endoscopies (7.1% of 155 post-PDT endoscopies with neoplastic diagnoses) of 8 patients. Their occurrence after PDT was neither associated with the length of BE, the diffuseness of neoplasms nor the presence of buried lesions before treatment. There was no prevalent location for these lesions in relation to the original segment of BE, although the majority of both surface and buried neoplasms were found in the prior neoplastic sites. Patients with buried neoplasms responded to further treatment similarly to those with only surface neoplasms (8 of 13 vs. 17 of 24) (P=0.33). In conclusion, buried neoplasms are not uncommon after PDT. Thorough endoscopic surveillance with extensive biopsies, especially of the sites previously positive for neoplasia is important to avoid overlooking buried neoplasms that may progress.

Photodynamic therapy for Barrett's esophagus with high-grade dysplasia

This article describes advances in photodynamic therapy for patients with Barrett's esophagus and high-grade dysplasia-an important, minimally invasive treatment option proven to safely and durably ablate Barrett's dysplasia and prevent carcinoma while preserving the gastroesophageal junction.

Cryoablation of Barrett's esophagus: a pilot study

BACKGROUND

Numerous ablative modalities have demonstrated varying degrees of efficacy in the eradication of Barrett's esophagus (BE). However, they are associated with either high cost, patient discomfort, complications, tedious application, residual underlying BE, or some combination of the above. The aim of this study was to evaluate the safety and the efficacy of a new cryogenic device by using liquid nitrogen sprayed through an open tipped cryogenic catheter placed through the accessory channel of an upper endoscope.

METHODS

A prospective, single center study was performed on patients with a long-standing history of BE followed in a Barrett's registry. Patients with degrees of dysplasia ranging from none to multifocal high-grade dysplasia were treated. All patients were treated with 40 mg rabeprazole 3 times per day during the treatment period. Elimination of acid reflux was confirmed via 24-hour esophageal pH studies. Cryoablation was applied hemicircumferentially to 4-cm-long segments at monthly intervals, until the entire segment of BE was eliminated.

RESULTS

Eleven patients were treated. There was reversal of BE in all patients. In 9 of 11 (78%) patients who completed the protocol, there was complete endoscopic and histologic reversal of BE. There was no subsquamous specialized intestinal metaplasia at the 6-month follow-up. No complications occurred.

CONCLUSIONS

Based on preliminary results, low-pressure spray cryoablation of BE under direct endoscopic visualization is safe and easy to perform. Its relative lack of patient discomfort and its simplicity and demonstrated efficacy make it a modality that should be further explored in the ablation of GI mucosal lesions such as BE and perhaps early esophageal cancer.

Laser Ablation Therapies for Barrett’s Esophagus

The metaplastic change of the normal squamous epithelium of the distal esophagus into a specialized columnar epithelium is known as Barrett's esophagus (BE) and is associated with an increased risk of adenocarcinoma of the esophagus. It is a frequent complication of gastroesophageal reflux disease (GERD) and up to 10% of patients with GERD suffer from BE. The progression to dysplasia increases the risk of cancer development and the annual risk of developing cancer in Barrett's esophagus is estimated to be 0.5% per year. The management of BE with high grade dysplasia (HGD) is controversial. Recent innovations in endoscopic therapy have allowed for the development of multiple endoscopic techniques, such as photodynamic therapy (PDT), argon plasma coagulation (APC), and endoscopic mucosal resection. In this article, we will discuss primarily photodynamic therapy, and other ablative technologies such as argon plasma coagulation in the treatment of BE.

Technology Insight: ablative techniques for Barrett's esophagus—current and emerging trends

New mucosal ablative techniques that can be used in the esophagus have emerged over the past two decades. These techniques have been developed primarily to treat the precursors of esophageal adenocarcinoma: dysplasia in Barrett's esophagus and early esophageal cancer. Although high-grade dysplasia and early stage cancer can be treated with esophagectomy, the inherent morbidity and mortality of esophageal adenocarcinoma and the morbidities, difficulties, costs and limitations of the current technology mean that there has been a significant increase in interest and research regarding alternative treatments such as ablative techniques. At this stage it is not clear which of the numerous endoscopic ablative techniques available-photodynamic therapy, laser therapy, multipolar electrocoagulation, argon plasma coagulation, endoscopic mucosal resection, radiofrequency ablation or cryotherapy-will emerge as superior. In addition, it has yet to be determined whether the risks associated with ablation therapy are less than the risk of Barrett's esophagus progressing to cancer. Whether ablation therapy eliminates or significantly reduces the risk of cancer, eliminates the need for surveillance endoscopy, or is cost-effective, also remains to be seen. Comparative trials that are now underway should help to answer these questions.

Management of superficial Barrett's epithelium-related neoplasms by endoscopic mucosal resection: clinicopathologic analysis of 27 cases

Endoscopic mucosal resection (EMR), a relatively new endoluminal therapeutic technique with low morbidity and no mortality reported to date, is advocated for the treatment of Barrett's esophagus (BE)-related superficial neoplasms. However, recent studies revise its success downward, particularly regarding the ability to achieve complete excision. To evaluate what remains an evolving technique, we analyzed our experience with a series of 27 esophageal EMRs (20 lesions in 18 patients). Our goal was to evaluate the diagnostic, staging, and therapeutic advantages of EMR separately by correlating the initial biopsies and pre-EMR endoscopic ultrasound (EUS) staging with the final histologic diagnoses and stage. Persistence/recurrence of neoplastic tissue was also correlated with the margin status of the resections. The mean size of the neoplasms, which included low-grade dysplasias (n=2), high-grade dysplasias (n=8), intramucosal carcinomas (n=14), and submucosal invasive carcinomas (n=3), was 11 mm. EUS correctly reported an intramucosal or submucosal lesion in 70% of the cases while it overstaged 18% and understaged 12% of the cases. The biopsy diagnosis corresponded to the EMR diagnosis in 63% of the cases. The biopsy underestimated the grade of the lesion in 21% of the cases. EMR revealed a lower histologic grade compared with the biopsy in 16% of the cases. The resection was microscopically complete in only 4% of the cases. No residual/recurrent disease was observed in 10 lesions (9 patients) at 4 to 63 months (mean, 23 months) post-EMR. However, 9 lesions (8 patients) persisted/recurred 28 days to 25 months (mean, 6 months) after treatment; 56% of the cases with positive lateral margin(s) and negative deep margin persisted/recurred. However, 86% of the EMRs with positive deep margin showed residual tumor/recurrence on follow-up biopsies. In conclusion, we observed that EMR offers improved diagnosis and staging as compared with biopsy and EUS. This is a significant advantage since it can modify patients' management. However, frequent incompleteness of resection and high persistence/recurrence are significant pitfalls that dictate continued endoscopic surveillance.