Cryotherapy for Barrett's Esophagus

Spray cryotherapy versus continued radiofrequency ablation in persistent Barrett's esophagus

Radiofrequency ablation (RFA) is the first-line treatment for flat Barrett's esophagus (BE) with dysplasia, however its role for persistent Barrett's esophagus (PBE) is unclear. PBE requires additional RFA sessions or application of cryotherapy to improve therapeutic response. We performed a retrospective cohort study evaluating cases of PBE treated by endoscopic eradication programs, with and without spray cryotherapy, and evaluated their safety and efficacy. We retrospectively identified patients with PBE, defined as ≤50% BE reduction or unchanged dysplasia after at least two RFA sessions. PBE was treated either by continued RFA (RFA Group) or converting to spray cryotherapy (CRYO Group), both followed by surveillance period. The rate of adverse events (AE), complete response of intestinal metaplasia (CRIM) and complete response of dysplasia (CRD) were recorded. A total of 46 patients, 23 per group, underwent 622 endoscopic therapies. Circumferential BE length was longer in the CRYO Group, but other baseline characteristics were similar, including maximal BE length. Esophageal strictures accounted for 14/16 total AE, 71% of which were RFA related, compared with 14% related to spray cryotherapy (P = 0.02). Overall CRIM/CRD rates in CRYO (83%) and RFA (96%) groups were not statistically different (P = 0.16), however cases in the CRYO Group required more treatment encounters (Median 19 vs. 12, P ≤ 0.01). Multimodal endotherapy is effective for eradicating PBE. Treatment programs incorporating spray cryotherapy are associated with less esophageal strictures but may require more treatment sessions to achieve eradication.

Comparative outcomes of radiofrequency ablation and cryoballoon ablation in dysplastic Barrett's esophagus: a propensity score-matched cohort study

BACKGROUND AND AIMS

Strong evidence supports the use of radiofrequency ablation (RFA) in the management of dysplastic/neoplastic Barrett's esophagus (BE). Recently, the efficacy of the cryoballoon ablation (CBA) system was demonstrated in multicenter cohort studies. We aimed to assess the comparative effectiveness and safety of these 2 ablation modalities for endoscopic eradication therapy (EET) in a cohort study.

METHODS

Data were abstracted on patients with dysplastic BE or intramucosal carcinoma undergoing EET using RFA or CBA as the primary ablation modality at 2 referral centers. The primary outcome was the rate of complete remission intestinal metaplasia (CRIM). Secondary outcomes were rates of complete remission of dysplasia (CRD) and adverse events. Cox proportional hazards models and propensity scored-matched analyses were conducted to compare outcomes.

RESULTS

Three hundred eleven patients (CBA, 85 patients; RFA, 226 patients) with a median follow-up of 1.5 years (interquartile range, .8, 2.5) in the RFA group and 2.0 years (interquartile range, 1.3, 2.5) in the CBA group were studied. On multivariable analyses, the chances of reaching CRD and CRIM were not influenced by ablation modality. Propensity score-matched analysis revealed a comparable chance of achieving CRIM (CBA vs RFA: hazard ratio, 1.24; 95% confidence interval, .79-1.96; P = .35) and CRD (CBA vs RFA: hazard ratio, 1.19; 95% confidence interval, .82-1.73; P = .36). The CBA group had a higher stricture rate compared with the RFA group (10.4% vs 4.4%, P = .04).

CONCLUSIONS

Histologic outcomes of EET using CBA and RFA for dysplastic BE appear to be comparable. A randomized trial is needed to definitively compare outcomes between these 2 modalities.

Allaying uncertainty in diagnosing buried Barrett's esophagus

Subsquamous intestinal metaplasia (SSIM) in the setting of Barrett's esophagus (BE) is a technically challenging diagnosis. While the risk for progression of BE involving the surface mucosa is well documented, the potential risk for development of advanced neoplasia associated with SSIM has been controversial. This study aimed to determine the effects of specimen adequacy, presence of dysplasia, and interobserver agreement for SSIM interpretation. Adult patients (n = 28) who underwent endoscopic therapy for BE with high-grade dysplasia or intramucosal carcinoma (HGD/IMC) between October 2005 and June 2013 were included. Initial evaluation (n = 140 slides) by an experienced gastrointestinal pathologist was followed by an interobserver study by 8 pathologists. Forty-seven (34%) slides had insufficient subsquamous tissue to assess for SSIM. SSIM was found in 19% of all slides and 29% of slides with sufficient subsquamous tissue. At least one slide had SSIM in 54% to 64% of patients. Subsquamous low grade dysplasia (LGD) was found in 4 (15%) slides with SSIM and subsquamous HGD/IMC was found in 5 (19%) slides with SSIM. At the patient level, 8 (53%) had no dysplasia, 4 (27%) had LGD and 3 (20%) had HGD/IMC. Overall agreement for SSIM by slide was 92% to 94% (κ = 0.73 to κ = 0.82, moderate to strong agreement), and by patient was 82% to 94% (κ = 0.65 to κ = 0.87, moderate to strong agreement). This study confirms the need for assessing specimen adequacy and assessing the prevalence of SSIM and is the first to assess interobserver agreement for SSIM and dysplasia within SSIM.

Optimizing the spray parameters of a cryospray process

Smaller spray zone of single-hole nozzle (SHN) constrains cryospray as a treatment method suitable for lesions having diameter larger than 15 mm on the skin surface. The present study is an attempt to resolve this issue, through the improvement in conventional technique of spraying liquid nitrogen on cancerous lesion. A multi-hole nozzle (MHN) with 5 holes is fabricated to demarcate the variation in outcome when cryogen is sprayed through customised MHN instead of conventional SHN. Special emphasis is placed on reducing the number of sitting required for completion of treatment and increasing the feasibility of cryospray process for larger lesions. Commercial SHN having a hole diameter of 0.8 mm is selected to compare results with the customised MHN having 5 holes of 0.8 mm diameter (4 holes are arranged in a circle of radius 2 mm around the central hole). Single freeze-thaw cycle is carried out to spray liquid nitrogen on tissue mimicking gel. Temperature profile accessed through infrared images advocates that lethal area formed through application of MHN is twice larger than the lethal area formed through the application of SHN on the surface of gel for same spraying distance (z). Thermocouples placed at various locations strengthen the fact that higher cooling rate (CR) corresponding to MHN ensures 15 mm spread of necrotic zone from the centre of spray (CS) and up to a depth of 2 mm from the gel surface while in case of SHN, it is limited to the vicinity of CS. On the basis of observations made through thermal images and digital images, it can be said that the ratio of lateral spread to penetration depth of ice ball remains almost same for SHN and MHN. However, the lateral spread of ice ball formed through the application of MHN is twice larger than SHN while the axial depth of ice ball does not record such increment. This reflects that MHN provides more destruction to superficial skin than SHN. Among the three spraying distances selected (i.e. z = 13 mm, 18 mm and 23 mm), the most optimised spraying distance (z) for MHN is also explored in this study. It has been found that cryoablation is not inversely proportional to the spraying distance. Spraying distance of z = 18 mm provided the most optimised result in terms of cryoablation.

A narrative review of Barrett's esophagus in 2020, molecular and clinical update

Barrett’s esophagus (BE) is a condition resulting from an acquired metaplastic epithelial change in the esophagus in response to gastroesophageal reflux. BE is the only known precursor lesion to esophageal adenocarcinoma, and can progress from non-dysplastic BE (NDBE) to low grade dysplasia (LGD) and high grade dysplasia (HGD), and ultimately invasive carcinoma. Although the risk of developing esophageal adenocarcinoma (EAC) in NBDE is less than 0.5% per year, there has been a rising incidence of EAC in Western countries, which continue to drive efforts to optimize screening and surveillance methods. The current gold standard for diagnosis is esophagogastroduodenoscopy (EGD), and there has been significant interest in alternative, minimally invasive methods for screening which would be more readily accessible in the primary care setting. Surveillance endoscopy in 3–5 years is recommended for NDBE given the low progression to EAC. The mainstay of treatment for LGD and HGD is endoscopic eradication therapy (EET). Visible lesions are treated with endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD). Radiofrequency ablation (RFA) is considered first line therapy for flat dysplastic BE and cryotherapy has shown promising results as an alternate form of treatment for of dysplasia. The molecular progression of BE to EAC is a complex process involving multiple pathways involving genetic and epigenetic modifications. Genomic studies have further led to the understanding of the complex molecular landscape that occurs early and late in the disease process. Promising biomarker panels have been investigated to help with the diagnosis of BE as well as aid in the risk stratification of BE during surveillance. In addition, clinical prediction models have been developed to categorize BE patients in low, intermediate, and high risk for progression to HGD and EAC. Further clinical and translational research is needed to help refine markers and techniques in diagnosis, screening, and surveillance.

Cryoballoon ablation for treatment of patients with refractory esophageal neoplasia after first line endoscopic eradication therapy

Background and study aims  Cryoablation with the Cryoballoon device is a novel ablative therapy that uses cycles of freezing and thawing to induce cell death. This single-center prospective study evaluated the feasibility of the focal cryoablation device for the treatment of areas of refractory esophageal neoplasia in patients who had undergone first line endoscopic eradication therapy (EET). Complete remission of dysplasia (CR-D) and complete remission of intestinal metaplasia (CR-IM) at first follow-up endoscopy, durability of disease reversal, rates of stenosis and adverse events were studied. Patients and methods  Eighteen cases were treated. At baseline, nine patients had low-grade dysplasia (LGD), six had high-grade dysplasia (HGD) and three had intramucosal carcinoma (IMC). Median length of dysplastic Barrett's esophagus (BE) treated was 3 cm. The median number of ablations per patient was 11. Each selected area of visible dysplasia received 10 seconds of ablation. One session of cryoablation was performed per patient. Biopsies were performed at around 3 months post-ablation. Results  CR-D was achieved in 78 % and CR-IM in 39 % of patients. There were no device malfunction or adverse events. Stenosis was noted in 11 % of cases. At a median follow up of 19-months, CR-D was maintained in 72 % of patients and CR-IM in 33 %. Conclusions  Cryoablation appears to be a viable rescue strategy in patients with refractory neoplasia. It is well tolerated and successful in obtaining CR-D and CR-IM in patients with treatment-refractory BE. Further trials of dosimetry, efficacy and safety in treatment-naïve patients are underway.

Efficacy of cryotherapy as first line therapy in patients with Barrett's neoplasia: a systematic review and pooled analysis

Cryotherapy has been used as salvage therapy; however, its efficacy as first line treatment in patients with Barrett's esophagus (BE) neoplasia has not been well studied. The aim of this paper was to perform a systematic review to look at the efficacy of cryotherapy as the primary treatment of BE. An electronic database search was performed (PubMed, Embase, Cochrane, and Google Scholar) to search for studies with cryotherapy as the initial primary modality of ablation in patients with BE neoplasia. Studies that included patients with other prior forms of therapy were excluded. The primary outcomes were the pooled rates of complete eradication of intestinal metaplasia (CE-IM) and CE of neoplasia (CE-N). Secondary outcomes were recurrence rates of neoplasia and intestinal metaplasia (IM) and adverse events. The statistical software OpenMetaAnalyst was used for analysis with pooled estimates reported as proportions (%) with 95% confidence intervals (CI) with heterogeneity (I2) among studies. The search revealed 6 eligible studies with a total of 282 patients (91.5% male, average age 65.3 years) with 459 person years of follow-up. 69.35% [95% CI (52.1%-86.5%)] of patients achieved CE-IM and 97.9% (95% CI: 95.5%-100%) had CE-N. 7.3% of patients had persistent dysplasia with 4% progressing to cancer. The recurrence rate of neoplasia was 10.4 and that of IM was 19.1 per 100 patient years of follow-up. The overall rate of stricture formation was 4.9%. There are scarce data on the use of cryotherapy as the primary modality for the treatment of BE dysplasia. The published data demonstrate efficacy rates of 69% and 98% for complete eradication of metaplasia and neoplasia, respectively. These results need to be assessed in prospective, comparative trials with other forms of therapy.

Spontaneous Pneumomediastinum, Pneumoperitoneum, and Pneumoretroperitoneum After Endoscopic Cryoablation Without Frank Perforation

Perforation after endoscopic cryoablation is a rare but serious complication. We present a middle-aged male patient who presented for an elective session of endoscopic cryoablation for his Barrett esophagus with high-grade dysplasia. After cryoablation, the patient complained of abdominal pain, and his abdomen became distended and tympanic. Computed tomography showed pneumomediastinum, pneumoperitoneum, and pneumoretroperitoneum but no evidence of extraluminal contrast extravasation. The patient was treated with antibiotics and had no complications. To our knowledge, this is the first described case of pneumomediastinum, pneumoperitoneum, and pneumoretroperitoneum without frank perforation after endoscopic cryoablation.

Endoscopic foregut surgery and interventions: The future is now. The state-of-the-art and my personal journey

In this paper, I reviewed the emerging field of endoscopic surgery and present data supporting the contention that endoscopy can now be used to treat many foregut diseases that have been traditionally treated surgically. Within each topic, the content will progress as follows: "lessons learned", "technical considerations" and "future opportunities". Lessons learned will provide a brief background and update on the most current literature. Technical considerations will include my personal experience, including tips and tricks that I have learned over the years. Finally, future opportunities will address current unmet needs and potential new areas of development. The foregut is defined as "the upper part of the embryonic alimentary canal from which the pharynx, esophagus, lung, stomach, liver, pancreas, and part of the duodenum develop". Foregut surgery is well established in treating conditions such as gastroesophageal reflux disease (GERD), achalasia, esophageal diverticula, Barrett's esophagus (BE) and esophageal cancer, stomach cancer, gastric-outlet obstruction, and obesity. Over the past decade, remarkable progress in interventional endoscopy has culminated in the conceptualization and practice of endoscopic foregut surgery for various clinical conditions summarized in this paper. Regarding GERD, there are now several technologies available to effectively treat it and potentially eliminate symptoms, and the need for long-term treatment with proton pump inhibitors. For the first time, fundoplication can be performed without the need for open or laparoscopic surgery. Long-term data going out 5-10 years are now emerging showing extended durability. In respect to achalasia, per-oral endoscopic myotomy (POEM) which was developed in Japan, has become an alternative to the traditional Heller's myotomy. Recent meta-analysis show that POEM may have better results than Heller, but the issue of post-POEM GERD still needs to be addressed. There is now a resurgence of endoscopic treatment of Zenker's diverticula with improved technique (Z-POEM) and equipment; thus, patients are choosing flexible endoscopic treatment as opposed to open or rigid endoscopy options. In regard to BE, endoscopic submucosal dissection (ESD) which is well established in Asia, is now becoming more mainstream in the West for the treatment of BE with high grade dysplasia, as well as early esophageal cancer. In combination with all the ablation technologies (radiofrequency ablation, cryotherapy, hybrid argon plasma coagulation), the entire spectrum of Barrett's and related dysplasia and early cancer can be managed predominantly by endoscopy. Importantly, in regard to early gastric cancer and submucosal tumors (SMTs) of the stomach, ESD and full thickness resection (FTR) can excise these lesions en-bloc and endoscopic suturing is now used to close large defects and perforations. For treatment of patients with malignant gastric outlet obstruction (GOO), endoscopic gastro-jejunostomy is now showing better results than enteral stenting. G-POEM is also emerging as a treatment option for patients with gastroparesis. Obesity has become an epidemic in many western countries and is becoming also prevalent in Asia. Endoscopic sleeve gastroplasty (ESG) is now becoming an established treatment option, especially for obese patients with body mass index between 30 and 35. Data show an average weight loss of 16 kg after ESG with long-term data confirming sustainability. Finally, in respect to endo-hepatology, there are many new endoscopic interventions that have been developed for patients with liver disease. Endoscopic ultrasound (EUS)-guided liver biopsy and EUS-guided portal pressure measurement are exciting new frontiers for the endo-hepatologists.

Cryotherapy in the management of premalignant and malignant conditions of the esophagus

Endoscopic cryotherapy is a relatively new thermal ablative modality used for the treatment of neoplastic lesions of the esophagus. It relies on cycles of rapid cooling and thawing to induce tissue destruction with a cryogen (liquid nitrogen or carbon dioxide) leading to intra and extra-cellular damage. Surgical treatment was once considered the standard therapeutic intervention for neoplastic diseases of the esophagus and is associated with considerable rates of morbidity and mortality. Several trials that evaluated cryotherapy in Barrett’s esophagus (BE) associated neoplasia showed reasonable efficacy rates and safety profile. Cryotherapy has also found applications in the treatment of esophageal cancer, both for curative and palliative intent. Cryotherapy has also shown promising results as salvage therapy in cases refractory to radiofrequency ablation treatment. Cryoballoon focal ablation using liquid nitrogen is a novel mode of cryogen delivery which has been used for the treatment of BE with dysplasia and squamous cell carcinoma. Most common side effects of cryotherapy reported in the literature include mild chest discomfort, esophageal strictures and bleeding. In conclusion, cryotherapy is an effective and safe method for the treatment of esophageal neoplastic processes, ranging from early stages of low grade dysplasia to esophageal cancer.

Multifocal nitrous oxide cryoballoon ablation with or without EMR for treatment of neoplastic Barrett's esophagus (with video)

BACKGROUND AND AIMS

Endoscopic cryotherapy can eradicate neoplastic Barrett's esophagus (BE). A new contact cryoballoon focal ablation system (CbFAS)) freezes esophageal mucosa with nitrous oxide. We studied the safety and efficacy of CbFAS for complete eradication of neoplastic Barrett's esophagus.

METHODS

In a prospective clinical trial, consecutive BE patients with confirmed neoplasia (low-grade dysplasia [LGD], high-grade dysplasia [HGD], and/or intramucosal adenocarcinoma [ImCA]), at least 1 cm of BE, with or without prior ablation, were treated with a dose 10 seconds of spray per site. EMR was performed for nodular lesions. Treatments were repeated every 10 to 12 weeks until complete eradication, with a maximum of 5 treatments. Primary outcomes were complete eradication of all dysplasia (CE-D) and complete eradication of intestinal metaplasia (CE-IM) at 1 year (intention-to-treat analysis).

RESULTS

Forty-one assessable patients (22 treatment naive, 19 previously ablated) with LGD (n = 13), HGD (n = 23), or ImCA (n = 5) were treated. The median procedure time was 30 minutes. The median number of ablation procedures for CE-IM was 3 (interquartile range, 2-4). Overall 1-year CE-D and CE-IM rates were 95% and 88%, respectively. CE-D rate was significantly lower (67%) in those with ultra-long BE compared with those with <8 cm (100%, P = .02). Median pain scores were zero at day 1. Four patients (9.7%) developed mild dysphagia from stenoses requiring dilation. One patient on aspirin developed upper GI bleeding that did not require therapy.

CONCLUSIONS

Multifocal nitrous oxide cryotherapy using CbFAS is a promising, highly effective, and safe endoscopic treatment for primary or rescue therapy of BE-associated neoplasia and IM. (Clinical trial registration number: NCT02534233.).

Mucosal Ablation in Patients with Barrett's Esophagus: Fry or Freeze?

The management of Barrett's esophagus and early esophageal adenocarcinoma has shifted away from esophagectomy and toward endoscopic techniques, including endoscopic resection and ablative therapies. The most commonly used ablative therapies are radiofrequency ablation and cryotherapy. Radiofrequency ablation has risen to the top of the management algorithm due to its favorable safety profile and established track record of efficacy in patients with dysplastic Barrett's. Cryotherapy offers early promise as an alternatively safe and effective ablative modality. We review radiofrequency ablation and cryotherapy techniques, and updated data regarding their efficacy and safety as well as their roles in the management of Barrett's esophagus.

Cryotherapy for persistent Barrett's esophagus after radiofrequency ablation: a systematic review and meta-analysis

BACKGROUND AND AIMS

A small but significant proportion of patients with Barrett's esophagus (BE) have persistent dysplasia or intestinal metaplasia (IM) after treatment with radiofrequency ablation (RFA). Cryotherapy is a cold-based ablative modality that is increasingly being used in this setting. We aimed to better understand the efficacy of second-line cryotherapy in patients with BE who have persistent dysplasia or IM after RFA by conducting a systematic review and meta-analysis.

METHODS

We performed a systematic literature search of Pubmed, EMBASE, and Web of Science through September 1, 2017. Articles were included for meta-analysis based on the following inclusion criteria: ≥5 patients with BE treated with RFA had persistent dysplasia or IM; they subsequently underwent ≥1 session of cryotherapy with follow-up endoscopy; the proportions of patients achieving complete eradication of dysplasia (CE-D) and/or IM (CE-IM) were reported. The main outcomes were pooled proportions of CE-D and CE-IM by using a random effects model.

RESULTS

Eleven studies making up 148 patients with BE treated with cryotherapy for persistent dysplasia or IM after RFA were included. The pooled proportion of CE-D was 76.0% (95% confidence interval [CI] 57.7-88.0), with substantial heterogeneity (I2 = 62%). The pooled proportion of CE-IM was 45.9% (95% CI, 32.0-60.5) with moderate heterogeneity (I2 = 57%). Multiple preplanned subgroup analyses did not sufficiently explain the heterogeneity. Adverse effects were reported in 6.7% of patients.

CONCLUSION

Cryotherapy successfully achieved CE-D in three fourths and CE-IM in half of patients with BE who did not respond to initial RFA. Considering its favorable safety profile, cryotherapy may be a viable second-line option for this therapeutically challenging cohort of patients with BE, but higher-quality studies validating this remain warranted.