A pilot study of endoscopic spray cryotherapy by pressurized carbon dioxide gas for Barrett's esophagus

The role of ablation in the treatment of dysplastic Barrett's esophagus

Endoscopic eradication therapy for Barrett's esophagus has been established as an effective management strategy for patients with Barrett's esophagus with dysplasia and early esophageal cancer. Among the endoscopic therapies, ablation techniques such as radiofrequency ablation and cryoablation are effective primary treatment interventions with acceptable low complication rates forming the spectrum of a multimodal approach. Appropriate selection of patients, high-definition endoscopic evaluation, and dedicated histological assessment are important cornerstones to help navigate to the best effective treatment method. Carefully structured surveillance programs and preventive measures will be needed to provide long-term durability for maintaining complete remission.

Updates in Cryotherapy for Barrett's Esophagus

Cryotherapy is an ablation modality relying on freeze-thaw cycles to promote cell death through intracellular ice crystal formation, ischemia, and apoptosis. Currently, 2 different cryotherapy systems are available for esophageal use. The first is cryospray ablation, which involves repetitive applications of liquid nitrogen. The second system, cryoballoon ablation, freezes the esophageal mucosa with liquid nitrous oxide using a compliant balloon. To date, studies have shown that cryotherapy is an effective and safe method for eradicating Barrett's esophagus; however, larger prospective series with longer follow-up are warranted to determine the clinical utility of cryotherapy in the treatment of Barrett's esophagus.

Efficacy of Cryotherapy as a Primary Endoscopic Ablation Modality for Dysplastic Barrett's Esophagus and Early Esophageal Neoplasia: A Systematic Review and Meta-Analysis

INTRODUCTION

Cryotherapy is a cold-based ablative therapy used primarily as second line therapy in patients with Barrett's esophagus (BE) who have persistent dysplasia after undergoing endoscopic treatment with radiofrequency ablation (RFA). Few studies have described the use of cryotherapy as a primary treatment modality for dysplastic or neoplastic BE.

AIM

To evaluate the efficacy of cryotherapy as primary treatment of dysplastic and/or neoplastic BE by conducting a systemic review and meta-analysis.

METHODS

A systematic search of Medline, Embase, and Web of Science was performed from January 2000 through March 2020. Articles included were observational studies and clinical trials which included patients who had biopsy confirmed dysplastic or neoplastic BE (i.e., high grade dysplasia (HGD), low grade dysplasia (LGD) or intramucosal adenocarcinoma (ImCA)), underwent ≥1 session of cryotherapy, and had a follow-up endoscopy. Primary outcomes were pooled proportions of patients achieving complete eradication of dysplasia (CE-D) and/or intestinal metaplasia (CE-IM) by using a random effects model.

RESULTS

Fourteen studies making up 405 patients with follow-up ranging from 3-54 months were included. In 13 studies, a total of 321/405 patients achieved CE-D with a pooled proportion of 84.8% (95% confidence interval [CI] 72.2-94.4), with substantial heterogeneity (I² = 88.3%). In 13 studies, a total of 321/405 patients achieved CE-D with a pooled proportion of 84.8% (95% confidence interval [CI] 72.2-94.4), with substantial heterogeneity (I² = 88.3%). Subgroup analysis of only high-quality studies revealed a pooled proportion of CE-D 91.3% (95% CI, 83.0-97.4, I² = 69.5%) and pooled proportion of CE-IM of 71.6% (95% CI, 59.0-82.9, I² = 80.9%). Adverse events were reported in 12.2% patients.

CONCLUSION

Cryotherapy is a safe and effective primary therapy for dysplastic/early neoplastic BE. CE-D and CE-IM rates are comparable to those for other ablation modalities, including RFA. Cryotherapy should be considered for primary therapy of dysplastic BE and early esophageal neoplasia.

Multifocal Cryoballoon Ablation for Eradication of Barrett's Esophagus-Related Neoplasia: A Prospective Multicenter Clinical Trial

INTRODUCTION

Ablation of Barrett's esophagus (BE) is the preferred approach for the treatment of neoplasia without visible lesions. Limited data on cryoballoon ablation (CBA) suggest its potential clinical utility. We evaluated the safety and efficacy of CBA in a multicenter study of patients with neoplastic BE.

METHODS

In a prospective clinical trial, 11 academic and community centers recruited consecutive patients with BE of 1-6 cm length and low-grade dysplasia, high-grade dysplasia (HGD), or intramucosal adenocarcinoma (ImCA) confirmed by central pathology. Patients with symptomatic pre-existing strictures or visible BE lesions had dilation or endoscopic mucosal resection (EMR), respectively, before enrollment. A nitrous oxide cryoballoon focal ablation system was used to treat all visible columnar mucosa in up to 5 sessions. Study end points included complete eradication of all dysplasia (CE-D) and intestinal metaplasia (CE-IM) at 1 year.

RESULTS

One hundred twenty patients with BE with ImCA (20%), HGD (56%), or low-grade dysplasia (23%) were enrolled. In the intention-to-treat analysis, the CE-D and CE-IM rates were 76% and 72%, respectively. In the per-protocol analysis (94 patients), the CE-D and CE-IM rates were 97% and 91%, respectively. Postablation pain was mild and short lived. Fifteen subjects (12.5%) developed strictures requiring dilation. One patient (0.8%) with HGD progressed to ImCA, which was successfully treated with EMR. Another patient (0.8%) developed gastrointestinal bleeding associated with clopidogrel use. One patient (0.8%) had buried BE with HGD in 1 biopsy, not confirmed by subsequent EMR.

DISCUSSION

In patients with neoplastic BE, CBA was safe and effective. Head-to-head comparisons between CBA and other ablation modalities are warranted (clinicaltrials.gov registration NCT02514525).

Liquid Nitrogen Spray Cryotherapy in Treatment of Barrett's Esophagus, where do we stand? A Systematic Review and Meta-Analysis

Radiofrequency ablation (RFA) is the preferred treatment option for Barrett's esophagus (BE) to achieve complete eradication (CE) of dysplasia (D), and intestinal metaplasia (IM). Cryotherapy, using liquid nitrogen (LNC), is a cold-induced tissue-injury technique option for the ablation of BE. We conducted a systematic review and meta-analysis to assess the overall efficacy and safety of LNC in the treatment of BE. We conducted a search of multiple electronic databases and conference proceedings from inception through June 2018. The primary outcome was to estimate the pooled rates of CE-IM, CE-D, and CE-HGD. The secondary outcome was to estimate the risk of adverse events and recurrence of disease after LNC. Nine studies reported 386 patients who were treated with LNC. The pooled rate of CE-IM was 56.5% (95% CI 48.5-64.2, I2 = 47), pooled rate of CE-D was 83.5% (95% CI 78.3-87.7, I2 = 22.8), and pooled rate of CE-HGD was 86.5% (95% CI 64.4-95.8, I2 = 88.1). Rate of adverse events was 4.7%, and the risk of BE recurrence was 12.7%. On subgroup analysis, the pooled rate of CE-IM with LNC in patients who failed RFA was 58.4% (95% CI 47.2-68.8, I2 = 32.5), and the pooled rate of CE-D in the same population was 81.9% (95% CI 72.5-88.6, I2 = 5.9). CE-D rates with LNC are comparable to RFA while CE-IM rates appear to be lower than the rates achievable with RFA. CE-IM rate in RFA failed patients is 58.4% and thus LNC is a rescue option to consider in this population.

Mucosal Ablation Techniques for Barrett's Esophagus and Early Esophageal Cancer

Patients with esophageal intestinal metaplasia, or Barrett's esophagus, may undergo dysplastic changes that eventually lead to invasive adenocarcinoma. Endoscopic therapy in the form of radiofrequency ablation and cryoablation has been described as a minimally invasive intervention to halt this sequence of dysplasia to carcinoma. Studies demonstrate that the use of radiofrequency ablation and cryoablation is highly successful at eradicating intestinal metaplasia and dysplasia and reducing the risk of disease progression. Furthermore, these modalities also may be used in combination with endoscopic mucosal resection, or as stand-alone therapy, for the treatment of intramucosal carcinoma, potentially circumventing the need for surgery.

Outcome of spray cryotherapy plus functional endoscopic sinus surgery on management of healing in nasal polyposis

BACKGROUND

Nasal Polyposis is a benign tumor in nasal or paranasal mucosa, which confronts difficulties in management of healing after treatments with surgery. The aim of this study was to evaluate the effects of Spray Cryotherapy (SCT) on management of healing in patients with nasal polyposis who undergone functional endoscopic sinus surgery.

METHODS

In this prospective, clinical trial study, we investigated on 40 patients with nasal polyposis that had indication for functional endoscopic sinus surgery. Patients were divided randomly into two parallel group; cryotherapy (with SCT) and placebo (without SCT). Evaluation of healing after surgery was evaluated with Lund-Mackay and The Sino-nasal outcome test (SNOT-22)-22 scores.

RESULT

Postoperatively, Lund-Mackay and SNOT-22 scores were significantly decreased in both groups, however these scores were significantly lower in cryotherapy group in comparison with placebo group. Also there were no reported serious side effects in both groups.

CONCLUSION

In this paper, we concluded that usage of SCT is an effective and safe method on management of healing and develops recovery rates in patients with nasal polyposis undergoing functional endoscopic sinus surgery.

Efficacy and safety of liquid nitrogen cryotherapy for treatment of Barrett’s esophagus

AIM

To evaluate the efficacy and safety of liquid nitrogen cryotherapy as a primary or rescue treatment for BE, with and without dysplasia, or intramucosal adenocarcinoma (IMC).

METHODS

This was a retrospective, single-center study carried out in a tertiary care center including 45 patients with BE who was treatment-naïve or who had persistent intestinal metaplasia (IM), dysplasia, or IMC despite prior therapy. Barrett’s mucosa was resected via EMR when clinically appropriate, then patients underwent cryotherapy until eradication or until deemed to have failed treatment. Surveillance biopsies were taken at standard intervals.

RESULTS

From 2010 through 2014, 33 patients were studied regarding the efficacy of cryotherapy. Overall, 29 patients (88%) responded to cryotherapy, with 84% having complete regression of all dysplasia and cancer. Complete eradication of cancer and dysplasia was seen in 75% of subjects with IMC; the remaining two subjects did not respond to cryotherapy. Following cryotherapy, 15 patients with high-grade dysplasia (HGD) had 30% complete regression, 50% IM, and 7% low-grade dysplasia (LGD); one subject had persistent HGD. Complete eradication of dysplasia occurred in all 5 patients with LGD. In 5 patients with IM, complete regression occurred in 4, and IM persisted in one. In 136 cryotherapy sessions amongst 45 patients, adverse events included chest pain (1%), stricture (4%), and one gastrointestinal bleed in a patient on dual antiplatelet therapy who had previously undergone EMR.

CONCLUSION

Cryotherapy is an efficacious and safe treatment modality for Barrett’s esophagus with and without dysplasia or intramucosal adenocarcinoma.

Cryotherapy for Barrett's Esophagus

Cryotherapy or cryoablation involves the freezing of tissues to destroy unwanted tissue or to control bleeding. Endoscopic cryotherapy has been developed for gastrointestinal application by through-the-scope noncontact delivery of compressed carbon dioxide gas or liquid nitrogen (cryospray) or contact balloon cryoablation. The mechanism of cryotherapy ablative effects includes immediate injury as well as coagulation necrosis occurring over several hours and days, unlike heat-based thermal ablation. This article reviews the basis, technique, safety, efficacy, and durability for the use of endoscopic cryotherapy in Barrett's esophagus and esophageal adenocarcinoma.

Cryoablation in the management of Barrett's esophagus

PURPOSE OF REVIEW

Providing an overview on types of cryotherapy for esophageal application and their role in the management of Barrett's esophagus.

RECENT FINDINGS

Recent studies have involved multiple types of cryotherapy including cryospray techniques that use either liquid nitrogen or carbon dioxide as the cryogenic fluid, and the CryoBalloon focal ablation device that uses nitrous oxide. Overall, studies report cryotherapy to be safe and effective in eradicating Barrett's epithelium. However, substantial variations among these studies in design and outcomes preclude direct comparisons of the results. Moreover, little is known of the long-term outcomes of cryotherapy, with only one report describing 5-year follow-up of patients treated with liquid nitrogen cryospray.

SUMMARY

The concept of cryotherapy is appealing. By preserving the extracellular matrix and inducing anesthetic effects, cryotherapy has the potential to enable deeper ablations with less pain and a lower rate of stricture formation than radiofrequency ablation. To date, however, these potential benefits remain unproved. Prospective studies with clearly defined endpoints and longer follow-up are necessary to determine the role of cryotherapy in the management of patients with Barrett's esophagus.

Detection and characterization of early malignancy in the esophagus: what is the best management algorithm?

Barrett's esophagus is a known precursor for esophageal adenocarcinoma. Early detection of dysplasia provides a window of opportunity for curative intervention. Several image-enhanced technologies have been developed to improve visualization of neoplasia. These however have not been found to be superior to the standard four quadrant random biopsy protocol. Patients are risk-stratified based on the degree of dysplasia found on biopsies and undergo either surveillance or treatment. Endoscopic therapy has become the mainstay of treatment for early neoplasia.

Cryospray ablation using pressurized CO2 for ablation of Barrett's esophagus with early neoplasia: early termination of a prospective series

BACKGROUND

Cryotherapy is a relatively novel ablation modality for the endoscopic ablation of Barrett's esophagus (BE). Data on the use of pressurized carbon dioxide (CO2) gas for cryoablation are scarce.

STUDY AIM

To determine the efficacy and safety of cryospray ablation using pressurized CO2 gas in the treatment of BE with early neoplasia.

METHODS

In this prospective single center case series, we aimed to include 30 patients with BE and early neoplasia. Nodular neoplastic lesions were treated with endoscopic mucosal resection (EMR). Residual BE mucosa was treated with cryospray ablation every 4 weeks until the complete BE segment was eliminated or up to seven treatment sessions. If no reduction of the BE segment was observed after two subsequent treatment sessions, cryoablation was terminated. Patients were contacted at days 1 and 4 post-treatment to evaluate the level of discomfort. Endoscopic and histologic follow-up evaluations were performed up to 24 months post-treatment.

RESULTS

After the inclusion of 10 patients, insufficient effect of cryoablation was observed, resulting in early termination of the study. In total, seven patients with intramucosal carcinoma (IMC) and three with high grade dysplasia (HGD) were included. Prior EMR was performed in nine patients. A median of 2.5 (IQR 2.0 - 4.0) cryoablation sessions were performed. At 6 months of follow-up, complete eradication of intestinal metaplasia was observed in 11 % (1 /9; one patient died, not treatment or disease related) of the patients and complete eradication of dysplasia in 44 % (4 /9). In three patients, HGD or IMC was detected during follow-up, and was endoscopically treated. Apart from a gastric perforation as a result of gastric distension caused by CO2 gas during the first treatment, cryospray treatments were well tolerated.

CONCLUSION

After a short learning curve, cryoablation using CO2 gas was found to be a safe and well tolerated treatment modality. However, in our experience, the efficacy of CO2 cryoablation combined with EMR for nodular lesions is disappointing for the treatment of BE associated neoplasia.

Efficacy of cryospray ablation for the treatment of chronic radiation proctitis in a pilot study

AIM

Radiation proctitis, a common condition associated with radiotherapy for the treatment of pelvic cancers, is characterized by difficult to manage rectal pain and bleeding. Cryotherapy is a novel technique, previously used in the treatment of vascular ectasias in the upper gastrointestinal tract. The aim of the present study was to determine the efficacy of cryospray application in the treatment of radiation proctitis.

METHODS

This is a prospective case-series pilot study. Ten patients with symptomatic chronic radiation proctitis were consecutively enrolled over a 2-year period. Baseline clinical data were collected and an endoscopic score was calculated based on the density of ectasias and circumferential involvement. Subjects underwent up to four cryospray ablation treatment sessions at approximately 4-week intervals or until resolution of the proctitis. The endpoints of the study were endoscopic and clinical improvement in radiation proctitis.

RESULTS

Ten patients (nine males and one female) with a mean age of 74 ± 7 years underwent cryospray treatment; sessions ranged from one to four (six patients had one session, three patients had two sessions, and one patient underwent four sessions). Endoscopic score significantly decreased from a mean of 10.2 ± 3.0 to 4.0 ± 2.8 (P = 0.016). Rectal pain significantly decreased from a mean of 3.1 ± 3.0 to 1.2 ± 1.7 (P = 0.042) and rectal bleeding improved in 86% (six out of seven) of patients. Nine patients reported improvement in overall well-being. No major complications were encountered.

CONCLUSIONS

Cryotherapy is an effective method in the management of chronic radiation proctitis with minimal complications.

Endoscopic therapy of Barrett esophagus

Barrett esophagus (BE) is a well-established premalignant condition for esophageal adenocarcinoma (EAC), a lethal cancer with a dismal survival rate. The current guidelines recommend surveillance of patients with BE to detect dysplasia or early cancer before the development of invasive EAC. Recently, endoscopic eradication therapies have been shown to be safe and effective in the treatment of BE-related high-grade dysplasia and early EAC. This article reviews the various treatment options for BE and discusses the current evidence and gaps in knowledge in the understanding of treatment of this condition. In addition, recommendations are provided in context to the recently published guidelines by the American Gastroenterological Association.

Minimally invasive treatments for Barrett's esophagus

The incidence of esophageal adenocarcinoma has been rising in recent years. Barrett's esophagus (BE) is widely considered the precursor of invasive adenocarcinoma. High-grade dysplasia (HGD) in BE is the critical step before invasive esophageal adenocarcinoma. Currently, numerous minimally invasive treatments for BE with HGD are available; however, there have been no clear-cut guidelines for a large number of patients due to the individualization of therapy and the absence of long-term outcome evaluation. This review briefly summarizes currently available minimally invasive therapeutic modalities for BE and compares their therapeutic outcomes, with an aim to aid in the choice of the appropriate treatment.

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.

Endoscopic therapies for Barrett's-associated dysplasia: a new paradigm for a new decade

The emergence of endoscopic therapies for Barrett's esophagus (BE)-associated dysplasia has significantly altered the management of this complex disease. Over the past decade, there has been a paradigm shift from that of pure surveillance to a more therapeutic approach in eradicating dysplastic BE. This strategy includes less invasive options than esophagectomy for high-grade dysplasia and early eradication of confirmed low-grade dysplasia. Although multiple modalities exist for endoscopic therapy, endoscopic mucosal resection coupled with radiofrequency ablation appears to be the most effective therapy, with minimal complications. Recent advances in endoscopic eradication therapies for dysplastic BE have fueled excitement for a significant weapon against the rising incidence of esophageal cancer.

Dose-dependent depth of tissue injury with carbon dioxide cryotherapy in porcine GI tract

BACKGROUND

Cryotherapy is a method of endoscopic mucosal ablation that involves delivery of a cryogen to result in tissue destruction by extreme low temperature. Its effects are influenced by the dosage of cryogen and thawing of ice. There are limited data on the tissue effects of multiple freeze and thaw cycles of carbon dioxide (CO(2)) cryotherapy on GI tissues.

OBJECTIVE

To investigate the extent of tissue injury due to escalating doses of CO(2) cryotherapy on the esophagus, stomach, and colon of pigs.

DESIGN

Animal experiment.

INTERVENTION

Varying doses of CO(2) cryotherapy with increasing number of freeze-thaw cycles were applied to each site. The animals were allowed to survive for 48 hours.

MAIN OUTCOME MEASUREMENTS

Depth of tissue injury assessed in blinded fashion by varying doses of cryotherapy on a defined area of porcine esophagus, stomach, and colon.

RESULTS

There was a dose-dependent relationship of CO(2) cryogen and depth of injury (P = .0001 and P = .002, respectively). In the stomach, the dose-response relationship was significant (P = .007), but the average grades of injury across the various doses were lower when compared with the esophagus at comparable cryogen doses (P = .0004). The estimated depth of tissue injury from the mucosal surface in the porcine esophagus and colon tissue ranged from 1.2 to 2.5 mm and 1.3 to 2.5 mm, respectively.

LIMITATIONS

The study was performed in a normal porcine model.

CONCLUSION

There was a dose-dependent relationship between the dose of CO(2) cryotherapy and the depth of tissue injury in the porcine esophagus, stomach, and colon.

Update on endoscopic diagnosis, management and surveillance strategies of esophageal diseases

In the last few decades, upper gastrointestinal endoscopy has become the most complementary test for investigation of esophageal diseases. Its accessibility and safety guarantee wide clinical utilization in patients with suspected benign and malignant diseases of the esophagus. Recent technological advances in endoscopic imaging and tissue analysis obtained from the esophagus have been useful to better understand and manage highly relevant diseases such as gastroesophageal reflux disease, eosinophilic esophagitis and esophageal cancer. Using endoscopy to elucidate esophageal disorders in children has been another field of intensive and challenging research. This editorial highlights the latest advances in the endoscopic management of esophageal diseases, and focuses on Barrett's esophagus, esophageal cancer, eosinophilic esophagitis, as well as esophageal disorders in the pediatric population.