Endoscopic ablation of dysplastic Barrett's oesophagus comparing argon plasma coagulation and photodynamic therapy: a randomized prospective trial assessing efficacy and cost-effectiveness

Endoscopic Therapies for Early Stage Esophageal and Gastric Cancers

Early detection of esophageal and gastric cancers offers the possibility of curative treatments with less-invasive interventions than traditional surgical approaches. This review highlights the main endoscopic therapeutic modalities used for early esophageal and gastric malignancies. Endoscopic resection techniques include endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). EMR is beneficial for smaller, well-defined lesions and involves resecting the superficial layer of the mucosa. In contrast, ESD permits en bloc resection of larger lesions, including those involving the superficial submucosa, offering precise histopathological assessments and reduced recurrence rates. As such, multidisciplinary collaboration is essential to achieve optimal outcomes.

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.

Comparison of interventions for Barrett's esophagus: A network meta-analysis

BACKGROUND AND OBJECTIVE

Barrett's esophagus (BE) is a precancerous condition that has the potential to develop into esophageal cancer (EC). Currently, there is a wide range of management options available for individuals at different pathological stages in Barrett's esophagus (BE). However, there is currently a lack of knowledge regarding their comparative efficacy. To address this gap, we conducted a network meta-analysis of published randomized controlled trials to examine the comparative effectiveness of all regimens.

METHODS

Data extracted from eligible randomized controlled trials were utilized in a Bayesian network meta-analysis to examine the relative effectiveness of BE's treatment regimens and determine their ranking in terms of efficacy. The ranking probability for each regimen was assessed using the surfaces under cumulative ranking values. The outcomes under investigation were complete ablation of BE, neoplastic progression of BE, and complete eradication of dysplasia.

RESULTS

We identified twenty-three RCT studies with a total of 1675 participants, and ten different interventions. Regarding complete ablation of non-dysplastic BE, the comparative effectiveness ranking indicated that argon plasma coagulation (APC) was the most effective regimen, with the highest SUCRA value, while surveillance and PPI/H2RA were found to be the least efficacious regimens. For complete ablation of BE with low-grade dysplasia, high-grade dysplasia, or esophageal cancer, photodynamic therapy (PDT) had the highest SUCRA value of 94.1%, indicating it as the best regimen. Additionally, for complete eradication of dysplasia, SUCRA plots showed a trend in ranking PDT as the highest with a SUCRA value of 91.2%. Finally, for neoplastic progression, radiofrequency ablation (RFA) and surgery were found to perform significantly better than surveillance. The risk of bias assessment revealed that 6 studies had an overall high risk of bias. However, meta-regression with risk of bias as a covariate did not indicate any influence on the model. In terms of the Confidence in Network Meta-Analysis evaluation, a high level of confidence was found for all treatment comparisons.

CONCLUSION

Endoscopic surveillance alone or PPI/H2RA alone may not be sufficient for managing BE, even in cases of non-dysplastic BE. However, APC has shown excellent efficacy in treating non-dysplastic BE. For cases of BE with low-grade dysplasia, high-grade dysplasia, or esophageal cancer, PDT may be the optimal intervention as it can induce regression of BE metaplasia and prevent future progression of BE to dysplasia and EC.

Interventional gastroenterology in oncology

Cancer is one of the foremost health problems worldwide and is among the leading causes of death in the United States. Gastrointestinal tract cancers account for almost one third of the cancer-related mortality globally, making it one of the deadliest groups of cancers. Early diagnosis and prompt management are key to preventing cancer-related morbidity and mortality. With advancements in technology and endoscopic techniques, endoscopy has become the core in diagnosis and management of gastrointestinal tract cancers. In this extensive review, the authors discuss the role endoscopy plays in early detection, diagnosis, and management of esophageal, gastric, colorectal, pancreatic, ampullary, biliary tract, and small intestinal cancers.

Adverse reactions of ALA-PDT for the treatment of cutaneous diseases: A retrospective study

BACKGROUND

5-Aminolaevulinic acid photodynamic therapy (ALA-PDT) is an effective therapy for cutaneous diseases, such as precancers, superficial non melanoma skin cancers and certain inflammatory or viral conditions. However, the absence of a complete picture of adverse reactions limits the promotion of ALA-PDT.

OBJECTIVE

To systemically investigate the detailed evidence of adverse reactions relating to ALA-PDT for skin diseases.

METHODS

A retrospective study performed at the Shanghai Skin Disease Hospital.

RESULTS

In the retrospective study, 439 patients were included. Incidences of adverse reactions, including in-treatment pain (98.8%), erythema (92.4%), edema (35.0%), exudation (23.0%), hyperpigmentation (27.3%) were clarified. Edema was more common in female patients (P<0.05). Patients with HPV-related skin diseases were more likely to suffer erythema, edema or exudation (P<0.05). Hyperpigmentation was more likely to occur in skin appendage disorders (P<0.05). Fever (2.4%) and hypopigmentation (1.9%) are two neglected adverse reactions analyzed in detail. Fever is more prevalent in female patients. Hypopigmentation occurred predominantly in elderly with skin cancer or precancerosis lesions.

CONCLUSION

The results outline detailed information about the adverse reactions, including systemic reactions following ALA-PDT, assisting dermatologists in predicting and managing adverse reactions for greater efficacy and higher patient satisfaction.

Hybrid APC in Combination With Resection for the Endoscopic Treatment of Neoplastic Barrett's Esophagus: A Prospective, Multicenter Study

INTRODUCTION

The current therapy of neoplastic Barrett's esophagus (BE) consists of endoscopic resection plus ablation, with radiofrequency ablation as the best studied technique. This prospective trial assesses a potential alternative, namely hybrid argon plasma ablation.

METHODS

Consecutive patients with neoplastic BE undergoing ablation after curative endoscopic resection (89.6%) or primarily were included into this prospective trial in 9 European centers. Up to 5 ablation sessions were allowed for complete eradication of BE (initial complete eradication of intestinal metaplasia [CE-IM]), by definition including BE-associated neoplasia, documented by 1 negative endoscopy with biopsies. The main outcome was the rate of initial CE-IM in intention-to-treat (ITT) and per-protocol (PP) samples at 2 years. The secondary end points were the rate of recurrence-free cases (sustained CE-IM) documented by negative follow-up endoscopies with biopsies and immediate/delayed adverse events.

RESULTS

One hundred fifty-four patients (133 men and 21 women, mean age 64 years) received a mean of 1.2 resection and 2.7 ablation sessions (range 1-5). Initial CE-IM was achieved in 87.2% of 148 cases in the PP analysis (ITT 88.4%); initial BE-associated neoplasia was 98.0%. On 2-year follow-up of the 129 successfully treated cases, 70.8% (PP) or 65.9% (ITT) showed sustained CE-IM; recurrences were mostly endoscopy-negative biopsy-proven BE epithelium and neoplasia in 3 cases. Adverse events were seen in 6.1%.

DISCUSSION

Eradication and recurrence rates of Barrett's intestinal metaplasia and neoplasia by means of hybrid argon plasma coagulation at 2 years seem to be within expected ranges. Final evidence in comparison to radiofrequency ablation can only be provided by a randomized comparative trial.

Endoscopic therapies for Barrett's esophagus

The management of Barrett's esophagus (BE) has evolved as newer technologies and novel methods are developed. Endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) are the initial interventions of choice for nodular BE, with ESD reserved for endoscopists highly trained in the technique and for larger lesions that would warrant en bloc resection. Resection should then be followed by ablative therapy, which remains first line in the treatment of BE with dysplasia. Although there is a myriad of ablation techniques available to the endoscopist, this review has found that radiofrequency ablation (RFA) continues to have the most robust safety and efficacy data to support its use despite a relatively high rate of recurrence. Cryotherapy and Hybrid-APC appear to be safe and effective as RFA alternatives, but further trials are still needed to directly compare their outcomes to RFA and ultimately guide changes in treatment decisions.

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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

SYSTEMATIC REVIEW REGISTRATIONS

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

Endoscopic management of esophageal cancer

Esophageal cancer (EC) generally consists of squamous cell carcinoma (which arise from squamous epithelium) and adenocarcinoma (which arise from columnar epithelium). Due to the increased recognition of risk factors associated with EC and the development of screening programs, there has been an increase in the diagnosis of early EC. Early EC is amenable to curative therapy by endoscopy, which can be performed by either endoscopic resection or endoscopic ablation. Endoscopic resection consists of either endoscopic mucosal resection (preferred in cases of adenocarcinoma) or endoscopic submucosal dissection (preferred in cases of squamous cell carcinoma). Endoscopic ablation can be performed by either radiofrequency ablation, cryotherapy, argon plasma coagulation or photodynamic therapy, amongst others. Endoscopy can also assist in the management of complications post-esophageal surgery, such as anastomotic leaks and perforations. Finally, there is a growing role for endoscopy to manage end-of-life palliative symptoms, especially dysphagia. The growing use of esophageal stents, debulking therapy and dilation can assist in improving a patient’s quality of life. In this review, we examine the multiple roles of endoscopy in the management of patients with EC.

Endoscopic Treatment of Early-Stage Esophageal Cancer

PURPOSE OF REVIEW

Esophageal cancer is a leading cause of global cancer-related mortality. Here, we discuss the major endoscopic treatment modalities for management of early esophageal cancer (EEC).

RECENT FINDINGS

Advances in endoscopic imaging and therapy have shifted the paradigm of managing early esophageal cancers. Though esophagectomy remains the preferred management for advanced cancers, guidelines now recommend endoscopic resection followed by ablative therapy for early (Tis and T1a) cancers. Available data suggests endoscopic treatment is comparable to surgery with regard to overall and cancer-specific survival with lower procedural morbidity and mortality. Endoscopic modalities are emerging as frontline treatment options for patients with early esophageal cancers. Accurate clinical staging with assessment of disease extent, tumor grade, and risk of nodal metastases is crucial when determining eligibility for endoscopic management of EEC. High-quality routine surveillance endoscopy is critical in patients who have undergone resection and/or ablation.

Depth-resolved imaging of colon tumor using optical coherence tomography and fluorescence laminar optical tomography

Early detection of neoplastic changes remains a critical challenge in clinical cancer diagnosis and treatment. Many cancers arise from epithelial layers such as those of the gastrointestinal (GI) tract. Current standard endoscopic technology is difficult to detect the subsurface lesions. In this research, we investigated the feasibility of a novel multi-modal optical imaging approach including high-resolution optical coherence tomography (OCT) and high-sensitivity fluorescence laminar optical tomography (FLOT) for structural and molecular imaging. The C57BL/6J-Apc^Min/J mice were imaged using OCT and FLOT, and the correlated histopathological diagnosis was obtained. Quantitative structural (scattering coefficient) and molecular (relative enzyme activity) parameters were obtained from OCT and FLOT images for multi-parametric analysis. This multi-modal imaging method has demonstrated the feasibility for more accurate diagnosis with 88.23% (82.35%) for sensitivity (specificity) compared to either modality alone. This study suggested that combining OCT and FLOT is promising for subsurface cancer detection, diagnosis, and characterization.

Emerging Concepts for the Endoscopic Management of Superficial Esophageal Adenocarcinoma

INTRODUCTION

Endoscopic therapy has revolutionized the treatment of Barrett's esophagus with high-grade dysplasia (HGD) or intramucosal adenocarcinoma by allowing preservation of the esophagus in many patients who would previously have had an esophagectomy. This paradigm shift initially occurred at high-volume centers in North America and Europe but now is becoming mainstream therapy. There is a lack of uniform guidelines and algorithms for the management of these patients. Our aim was to review important concepts and pitfalls in the endoscopic management of superficial esophageal adenocarcinoma.

METHODS

A small group colloquium consisting of gastroenterologists, surgeons, and pathologists reviewed published data and discussed personal and institutional experiences with endotherapy for HGD and superficial esophageal adenocarcinoma.

RESULTS

The group reviewed data and provided recommendations and management algorithms for seven areas pertaining to endoscopic therapy for Barrett's HGD and superficial adenocarcinoma: (1) patient selection and evaluation; (2) imaging and biopsy techniques; (3) devices; (4) indications for resection versus ablation; (5) ER specimen handling, processing, and pathologic evaluation; (6) patient care and follow-up after endoscopic therapy; and (7) complications of endoscopic therapy and treatment options.

CONCLUSIONS

Endoscopic therapy is preferred over esophagectomy for most patients with HGD or intramucosal adenocarcinoma, and may be applicable to select patients with submucosal tumors. Clear guidelines and management algorithms will aid physicians and centers embarking on endoscopic therapy and enable a standardized approach to the management of these patients that is applicable internationally.

Management of Barrett's oesophagus

Barrett's oesophagus is associated with the development of oesophageal adenocarcinoma. This review highlights the management strategies currently used in the treatment of this condition.

Endoscopic options for early stage esophageal cancer

Surgery has traditionally been the preferred treatment for early stage esophageal cancer. Recent advances in endoscopic treatments have been shown to be effective and safe. Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) allow endoscopists to remove small, superficial lesions, providing tumor specimen that can be examined for accurate pathologic tumor staging and assessment of adequacy of resection. Endoscopic ablation procedures, including photodynamic therapy (PDT) and radio frequency ablation (RFA), have also been shown to safely and effectively treat esophageal dysplasia and early stage neoplasia, with excellent long-term disease control. Both approaches are becoming more widely available around the world, and provide an alternative, safe, low risk strategy for treating early stage disease, making combined endoscopic therapy the recommended treatment of choice for early stage esophageal cancers.

Strategies for the prevention of oesophageal adenocarcinoma

The incidence of oesophageal adenocarcinoma has increased by 500% over the past 30 years [1]. Improved understanding of the mechanisms of neoplastic progression provides an opportunity to reverse this trend. A thorough review of emerging strategies aiming to prevent the formation of oesophageal malignancy is presented. These include dietary modification, chemoprevention, early endoscopic identification and treatment of premalignant disease, and the potential for a non-endoscopic screening test. Oesophageal adenocarcinoma has become a major public health problem in the West and it is essential that clinicians are fully informed of risk reduction strategies so that they can be actively promoted in the community.

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.

Meta-analysis of endoscopic therapy for low-grade dysplasia in Barrett's oesophagus

Background

The optimal management of patients with Barrett's-associated low-grade dysplasia (LGD) is unclear. The objective of this study was to identify systematically all reports of endoscopic treatment of LGD, and to assess outcomes in terms of disease progression, eradication of dysplasia and intestinal metaplasia, and complication rates.

Methods

A systematic review of articles reporting endoscopic treatment of LGD was conducted in accordance with PRISMA guidelines. MEDLINE and Embase databases were searched to identify the relevant literature. Rates of complete eradication of intestinal metaplasia (CE-IM) and dysplasia (CE-D) were reported. The pooled incidence of progression to cancer was calculated following endoscopic therapy.

Results

Thirty-seven studies met the inclusion criteria, reporting outcomes of endoscopic therapy for 521 patients with LGD. The pooled incidence of progression to cancer was 3·90 (95 per cent confidence interval (c.i.) 1·27 to 9·10) per 1000 patient-years. CE-IM and CE-D were achieved in 67·8 (95 per cent c.i. 50·2 to 81·5) and 88·9 (83·9 to 92·5) per cent of patients respectively. The commonest adverse event was stricture formation.

Conclusion

Reports of endoscopic therapy were heterogeneous and follow-up periods were short. There is a high likelihood of historical overdiagnosis of LGD. Endoscopic therapy, particularly radiofrequency ablation, appears safe and effective at eradicating LGD, but does not eliminate the risk of progression to cancer.

Low grade dysplasia in Barrett’s esophagus: Should we worry?

The optimal management for low-grade dysplasia (LGD) in Barrett’s esophagus is unclear. In this article the importance of LGD is discussed, including the significant risk of progression to esophageal adenocarcinoma. Endoscopic surveillance is a management option but is plagued by sampling error and issues of suboptimal endoscopy. Furthermore endoscopic surveillance has not been demonstrated to be cost-effective or to reduce cancer mortality. The emergence of endoluminal therapy over the past decade has resulted in a paradigm shift in the management of LGD. Ablative therapy, including radiofrequency ablation, has demonstrated promising results in the management of LGD with regards to safety, cost-effectiveness, durability and reduction in cancer risk. It is, however, vital that a shared-decision making process occurs between the physician and the patient as to the preferred management of LGD. As such the management of LGD should be “individualised.”

Endoscopic Optical Coherence Tomography for Clinical Gastroenterology

Optical coherence tomography (OCT) is a real-time optical imaging technique that is similar in principle to ultrasonography, but employs light instead of sound waves and allows depth-resolved images with near-microscopic resolution. Endoscopic OCT allows the evaluation of broad-field and subsurface areas and can be used ancillary to standard endoscopy, narrow band imaging, chromoendoscopy, magnification endoscopy, and confocal endomicroscopy. This review article will provide an overview of the clinical utility of endoscopic OCT in the gastrointestinal tract and of recent achievements using state-of-the-art endoscopic 3D-OCT imaging systems.

Management controversies in Barrett's oesophagus

The management of Barrett's oesophagus and associated neoplasia has evolved considerably in recent years. Modern endoscopic strategies including endoscopic resection and mucosal ablation can eradicate dysplastic Barrett's and prevent progression to invasive oesophageal cancer. However, several aspects of Barrett's management remain controversial including the stage in the disease process at which to intervene, and the choice of endoscopic or surgical therapy. A review of articles pertaining to the management of Barrett's oesophagus with or without associated neoplasia, was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Medline, Embase and Cochrane databases were searched to identify literature relevant to eight pre-defined areas of clinical controversy. The following search terms were used: Barrett's oesophagus; dysplasia; intramucosal carcinoma; endotherapy; endoscopic resection; ablation; oesophagectomy. A significant body of evidence exists to support early endoscopic therapy for high-grade dysplasia (HGD). Although not supported by randomised controlled trial evidence, endoscopic therapy is now favoured ahead of oesophagectomy for most patients with HGD. Focal intramucosal (T1a) carcinomas can be managed effectively using endoscopic and surgical therapy, however surgery should be considered the first line therapy where there is submucosal invasion (T1b). Treatment of low grade dysplasia is not supported at present due to widespread over-reporting of the disease. The role of surveillance endoscopy in non-dysplastic Barrett's remains controversial.

British Society of Gastroenterology guidelines on the diagnosis and management of Barrett's oesophagus

These guidelines provide a practical and evidence-based resource for the management of patients with Barrett's oesophagus and related early neoplasia. The Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument was followed to provide a methodological strategy for the guideline development. A systematic review of the literature was performed for English language articles published up until December 2012 in order to address controversial issues in Barrett's oesophagus including definition, screening and diagnosis, surveillance, pathological grading for dysplasia, management of dysplasia, and early cancer including training requirements. The rigour and quality of the studies was evaluated using the SIGN checklist system. Recommendations on each topic were scored by each author using a five-tier system (A+, strong agreement, to D+, strongly disagree). Statements that failed to reach substantial agreement among authors, defined as >80% agreement (A or A+), were revisited and modified until substantial agreement (>80%) was reached. In formulating these guidelines, we took into consideration benefits and risks for the population and national health system, as well as patient perspectives. For the first time, we have suggested stratification of patients according to their estimated cancer risk based on clinical and histopathological criteria. In order to improve communication between clinicians, we recommend the use of minimum datasets for reporting endoscopic and pathological findings. We advocate endoscopic therapy for high-grade dysplasia and early cancer, which should be performed in high-volume centres. We hope that these guidelines will standardise and improve management for patients with Barrett's oesophagus and related neoplasia.

Photodynamic Therapy for Barrett's Esophagus and Esophageal Carcinoma

This paper reviews the use of photodynamic therapy (PDT) in patients with Barrett's esophagus and esophageal carcinoma. We describe the history of PDT, mechanics, photosensitizers for PDT in patients with esophageal disease. Finally, we discuss its utility and limitations in this setting.

Diagnosis and treatment of Barrett's oesophagus

INTRODUCTION

Barrett's oesophagus (BO) is a common premalignant condition, which carries a risk of progression to oesophageal adenocarcinoma. Recent advances include quantifying the risk of neoplasia progression, novel diagnostic tools and development of new endoscopic techniques to treat early Barrett's cancer.

SOURCES OF DATA

A selective search was performed on recent advances in BO and this was supplemented with guidelines from the American and British Society of Gastroenterology.

AREAS OF AGREEMENT

All cases of dysplasia should be confirmed by a second expert histopathologist. Endoscopic therapy is the preferred option for high-grade dysplasia and intra-mucosal (T1a) carcinoma using endomucosal resection (EMR) and/or radiofrequency ablation. EMR also provides accurate staging information and any remaining Barrett segment should be ablated to reduce the risk of metachronous lesions.

AREAS OF CONTROVERSY

The cell of origin for BO is not certain. The merits and cost effectiveness of endoscopic screening and surveillance still remain controversial. The risk of neoplasia progression in low-grade dysplasia is inconsistently reported. The role of chemoprevention remains unclear.

GROWING POINTS

The use of radical endotherapy in early Barrett's neoplasia is promising with some data supporting long-term durability.

AREAS TIMELY FOR DEVELOPING RESEARCH

The development of non-endoscopic diagnostic tools and radical endotherapy to treat early cancer strengthens the argument for surveillance and suggests the possibility of screening in the near future. Identification of a biomarker may help to select high-risk patients.

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.

Molecular biomarkers and ablative therapies for Barrett's esophagus

Barrett's esophagus is the major risk factor for esophageal adenocarcinoma. Endoscopic interventions that ablate Barrett's esophagus mucosa lead to replacement with a new squamous (neosquamous) mucosa, but it can be difficult to achieve complete ablation. Knowing whether cancer is less likely to develop in neosquamous mucosa or residual Barrett's esophagus after ablation is critical for determining the efficacy of treatment. This issue can be informed by assessing biomarkers that are associated with an increased risk of progression to adenocarcinoma. Although there are few postablation biomarker studies, evidence suggests that neosquamous mucosa may have a reduced risk of adenocarcinoma in patients who have been treated for dysplasia or cancer, but some patients who do not have complete eradication of nondysplastic Barrett's esophagus may still be at risk. Biomarkers could be used to optimize endoscopic surveillance strategies following ablation, but this needs to be assessed by clinical studies and economic modeling.

Management of Barrett's oesophagus and intramucosal oesophageal cancer: a review of recent development

Barrett's oesophagus is the most important and recognizable precursor lesion for oesophageal adenocarcinoma, which is the one of the fastest growing cancers in the Western World. The incidence of oesophageal adenocarcinoma has increased 600% in the United States between 1975 and 2001 and is thought to represent a real increase in burden rather than a result of histologic or anatomical misclassification or overdiagnosis. Thus, the cancer risk in Barrett's oesophagus has to be managed and involves prevention (surveillance endoscopy), treating underlying gastroesophageal reflux disease (medically and or surgically) and endoscopic therapy to remove diseased epithelium in appropriate patient subgroups. In the last decade, new developments in imaging and molecular markers as well as an armamentarium of novel and effective endoscopic eradication therapy has become available to the endoscopist to combat this exponential rise in oesophageal adenocarcinoma. Paradoxically, the cancer risk in Barrett's oesophagus gets progressively downgraded which raises fundamental questions about our understanding of the known and unknown risk factors and molecular aberrations that are involved in the Barrett's metaplasia-dysplasia-carcinoma sequence. Future research has to be directed at these areas to fine tune our screening and surveillance programs to identify more accurately the high-risk group of progressors to oesophageal adenocarcinoma who would benefit most from endoscopic therapy.

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.

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.

Management of cancer risk in Barrett's esophagus

The importance of Barrett's esophagus (BE) lies in its potential to give rise to esophageal adenocarcinoma (EAC), postulated to be through a series of progressive degrees of dysplasia; from intestinal metaplasia to low-grade dysplasia, high-grade dysplasia, and subsequently, to cancer. The management strategies for the detection and treatment of dysplasia and early esophageal cancer on a background of BE have changed significantly in the last few decades, with the emergence of newer and less invasive non-operative alternatives. This review aims to outline BE and its relation to EAC, the rationale and cost-effectiveness of both screening and surveillance programs, methods of diagnosing and identifying dysplasia and early cancer in Barrett's, and approaches to individualizing their endoscopic and surgical management based on best-available staging techniques.

Barrett's esophagus: endoscopic treatments II

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

[Endoscopic treatments for Barrett oesophagus]

High grade dysplasia and superficial carcinomas (with no extension under muscularis mucosae) can be indications for endoscopic treatments of Barrett oesophagus. When an endoscopic treatment is considered, a gastroscopy with use of acetic acid and planimetry and the confirmation of high-grade dysplasia by a new examination after PPI treatment and a pathologic second confirmation is needed. For high-grade dysplasia in focalised and visible lesions, an endoscopic resection by EMR or ESD should be proposed: it allows a more accurate pathologic examination and can be an effective curative treatment. After endoscopic resection of visible high grade dysplasia lesions, a complete eradication of Barrett oesophagus may be proposed to prevent dysplasia recurrence. In case of extensive high-grade dysplasia or to eradicate Barrett oesophagus residual lesions, radiofrequency ablation is the preferred endoscopic technique. Photodynamic therapy may also be proposed for more invasive lesions or after other endoscopic techniques with mucosal scars. Surgical oesophagus resection is still recommended for diffuse high-grade dysplasia in young patients or in case of pathologic pejorative criteria in endoscopic resection specimen. In case of Low-grade dysplasia, either endoscopic surveillance should be performed every six or 12 months or radiofrequency ablation could be proposed in the yield of prospective studies.

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.

Effectiveness, safety, and cost-effectiveness of photodynamic therapy in Barrett's esophagus: a systematic review

Barrett's esophagus, the management of which remains controversial, is the precursor condition to esophageal adenocarcinoma. A number of endoscopic treatments have been designed as an alternative to surgical resection for patients with high-grade dysplasia. One of these, photodynamic therapy, involves the light activation of a photosensitizer that causes local tissue destruction via oxidation reactions. The present work reviews the effectiveness, safety, and cost-effectiveness of this treatment. A systematic review of the literature recorded in the Medline, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Database, and the National Health Service Economic Evaluation Database was undertaken. Articles reporting randomized clinical trials of photodynamic therapy for the treatment of Barrett's esophagus, and economic assessments of the procedure, were selected. The quality of the articles was checked. Twelve articles were included in this review: eight randomized, controlled clinical trials and four economic assessments. The clinical trials suffered from methodological limitations, but the economic assessments were considered to be good quality. Photodynamic therapy is effective for the ablation of dysplasia in Barrett's esophagus, although the frequency of adverse events is quite high. The procedure is presented as a cost-effective alternative to intense endoscopic monitoring and esophagectomy. However, the evidence regarding its effectiveness in reducing the number of patients who go on to develop cancer is only incipient. Rigorous, controlled studies with longer follow-up times, in which photodynamic therapy is compared with surgical resection and other endoscopic techniques, are needed.

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.

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.

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.

Photodynamic therapy for Barrett's esophagus: a systematic review

AIM: To evaluate the efficacy and safety of photodynamic therapy (PDT) for Barrett's esophagus (BE).

METHODS: We searched Cochrane Clinical Trial Register (Issue 4, 2009), Medline or PubMed (1978-2010), EMBase (1978-2010), OVID database (1978-2010), Chinese Biological Medicine database (CBMDisc) (1978-2010), CNKI (1979-2010), Chinese VIP database (1989-2010) and Wanfang database (1978-2010). We also manually searched the bibliographies of retrieved articles and four kinds of important journals to identify randomized controlled trials of PDT for BE. A systematic review was conducted using the method recommended by the Cochrane collaboration.

RESULTS: Ten randomized controlled trials involving 731 patients were included in this systematic review. Three trials reported that PDT could provide safe and effective ablation of low-grade dysplastic epithelium, and proposed that PDT could be used for the treatment of BE at 4-5 h after ALA ingestion and low-dose PDT appeared to be a safe protocol for BE. Three trials showed that PDT in combination with omeprazole was an effective therapy for ablating HGD in patients with BE and in reducing the incidence of esophageal adenocarcinoma. Three trials reported that APC and PDT were equally effective in eradicating Barrett's mucosa, with PDT being the more expensive treatment. However, PDT is more effective in eradicating dysplasia. One trial showed that oral prednisone after PDT did not reduce the incidence of esophageal strictures.

CONCLUSION: PDT is an effective therapy for ablating HGD in patients with BE and in reducing the incidence of esophageal adenocarcinoma. Low-dose PDT is better tolerated in patients with BE.

The safety and effectiveness of endoscopic and non-endoscopic approaches to the management of early esophageal cancer: a systematic review

INTRODUCTION

Traditionally, management of early cancer (stages 0-IIA) has comprised esophagectomy, either alone or in combination with chemotherapy and/or radiotherapy. Recent efforts to improve outcomes and minimize side-effects have focussed on minimally invasive, endoscopic treatments that remove lesions while sparing healthy tissue. This review assesses their safety and efficacy/effectiveness relative to traditional, non-endoscopic treatments for early esophageal cancer.

METHODS

A systematic review of peer-reviewed studies was performed using Cochrane guidelines. Bibliographic databases searched to identify relevant English language studies published in the last 3 years included: PubMed (i.e., MEDLINE and additional sources), EMBASE, CINAHL, The Cochrane Library, the UK Centre for Reviews and Dissemination (NHS EED, DARE and HTA) databases, EconLit and Web of Science. Web sites of professional associations, relevant cancer organizations, clinical practice guidelines, and clinical trials were also searched. Two independent reviewers selected, critically appraised, and extracted information from studies.

RESULTS

The review included 75 studies spanning 3124 patients and 10 forms of treatment. Most studies were of short term duration and non-comparative. Adverse events reported across studies of endoscopic techniques were similar and less significant compared to those in the studies of non-endoscopic techniques. Complete response rates were slightly lower for photodynamic therapy (PDT) relative to the other endoscopic techniques, possibly due to differences in patient populations across studies. No studies compared overall or cause-specific survival in patients who received endoscopic treatments vs. those who received non-endoscopic treatments.

DISCUSSION

Based on findings from this review, there is no single "best practice" approach to the treatment of early esophageal cancer.

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.

Safety, tolerability, and efficacy of endoscopic low-pressure liquid nitrogen spray cryotherapy in the esophagus

Endoscopic cryotherapy is a new technique for ablation of esophageal dysplasia and neoplasia. Preliminary studies have shown it to be safe and effective for this indication. The objective of this study is to characterize safety, tolerability, and efficacy of low-pressure liquid nitrogen endoscopic spray cryotherapy ablation in a large cohort across multiple study sites. Parallel prospective treatment studies at four tertiary care academic medical centers in the U.S. assessed spray cryotherapy in patients with Barrett's esophagus with or without dysplasia, early stage esophageal cancer, and severe squamous dysplasia who underwent cryotherapy ablation of the esophagus. All patients were contacted between 1 and 10 days after treatment to assess for side effects and complications of treatment. The main outcome measurement was the incidence of serious adverse events and side effects from treatment. Complete response for high-grade dysplasia (HGD) (CR-HGD), all dysplasia (CR-D), intestinal metaplasia (CR-IM) and cancer (CR-C) were assessed in patients completing therapy during the study period. A total of 77 patients were treated for Barrett's high-grade dysplasia (58.4%), intramucosal carcinoma (16.9%), invasive carcinoma (13%), Barrett's esophagus without dysplasia (9.1%), and severe squamous dysplasia (2.6%). Twenty-two patients (28.6%) reported no side effects throughout treatment. In 323 procedures, the most common complaint was chest pain (17.6%) followed by dysphagia (13.3%), odynophagia (12.1%), and sore throat (9.6%). The mean duration of any symptoms was 3.6 days. No side effects were reported in 48% of the procedures (155/323). Symptoms did not correlate with age, gender, diagnosis, or to treatment early versus late in the patient's or site's experience. Logit analysis showed that symptoms were greater in those with a Barrett's segment of 6 cm or longer. Gastric perforation occurred in one patient with Marfan's syndrome. Esophageal stricture developed in three, all successfully treated with dilation. In 17 HGD patients, cryotherapy produced CR-HGD, CR-D, and CR-IM of 94%, 88%, and 53%, respectively. Complete regression of cancer and HGD was seen in all seven patients with intramucosal carcinoma or stage I esophageal cancer. Endoscopic spray cryotherapy ablation using low-pressure liquid nitrogen in the esophagus is safe, well-tolerated, and efficacious.

The role of photodynamic therapy in the esophagus

Photodynamic therapy (PDT) is a drug and device therapy using photosensitizer drugs activated by laser light for mucosal ablation. Porfimer sodium PDT has been used extensively with proven long-term efficacy and durability for the ablation of Barrett esophagus and high-grade dysplasia. and early esophageal adenocarcinoma. However, continued use is hampered by an associated stricture risk and prolonged photosensitivity (4-6 weeks). Promising single-center European studies using other forms of PDT, such as aminolevulinic acid PDT, have not been replicated elsewhere, limiting the widespread use of other forms of PDT. Future use of PDT in esophageal disease depends on the development of improved dosimetry and patient selection to optimize treatment outcomes, while minimizing adverse events and complications.

Safety, tolerability, and efficacy of endoscopic low-pressure liquid nitrogen spray cryotherapy in the esophagus

Endoscopic cryotherapy is a new technique for ablation of esophageal dysplasia and neoplasia. Preliminary studies have shown it to be safe and effective for this indication. The objective of this study is to characterize safety, tolerability, and efficacy of low-pressure liquid nitrogen endoscopic spray cryotherapy ablation in a large cohort across multiple study sites. Parallel prospective treatment studies at four tertiary care academic medical centers in the U.S. assessed spray cryotherapy in patients with Barrett's esophagus with or without dysplasia, early stage esophageal cancer, and severe squamous dysplasia who underwent cryotherapy ablation of the esophagus. All patients were contacted between 1 and 10 days after treatment to assess for side effects and complications of treatment. The main outcome measurement was the incidence of serious adverse events and side effects from treatment. Complete response for high-grade dysplasia (HGD) (CR-HGD), all dysplasia (CR-D), intestinal metaplasia (CR-IM) and cancer (CR-C) were assessed in patients completing therapy during the study period. A total of 77 patients were treated for Barrett's high-grade dysplasia (58.4%), intramucosal carcinoma (16.9%), invasive carcinoma (13%), Barrett's esophagus without dysplasia (9.1%), and severe squamous dysplasia (2.6%). Twenty-two patients (28.6%) reported no side effects throughout treatment. In 323 procedures, the most common complaint was chest pain (17.6%) followed by dysphagia (13.3%), odynophagia (12.1%), and sore throat (9.6%). The mean duration of any symptoms was 3.6 days. No side effects were reported in 48% of the procedures (155/323). Symptoms did not correlate with age, gender, diagnosis, or to treatment early versus late in the patient's or site's experience. Logit analysis showed that symptoms were greater in those with a Barrett's segment of 6 cm or longer. Gastric perforation occurred in one patient with Marfan's syndrome. Esophageal stricture developed in three, all successfully treated with dilation. In 17 HGD patients, cryotherapy produced CR-HGD, CR-D, and CR-IM of 94%, 88%, and 53%, respectively. Complete regression of cancer and HGD was seen in all seven patients with intramucosal carcinoma or stage I esophageal cancer. Endoscopic spray cryotherapy ablation using low-pressure liquid nitrogen in the esophagus is safe, well-tolerated, and efficacious.