366 Safety and Efficacy of Cryoablation Balloon for the Treatment of Barrett’s Associated Neoplasia: A Meta-Analysis

Abstract

INTRODUCTION: The Cryoballoon Focal Ablation System (CbFAS) (CryoBalloon; Pentax Medical, Redwood City, California, USA), a novel device that permits the conversion of liquid nitrous oxide into its gaseous form within a contact balloon system, was recently introduced for the endoscopic ablation of Barrett’s esophagus (BE) associated neoplasia. We performed a meta-analysis to assess the feasibility, efficacy, and safety of the CbFAS for the treatment of BE neoplasia. METHODS: Several databases were searched for relevant articles (PubMed, Web of Science, Google Scholar, EMBASE) as well as abstracts of recent gastroenterology meetings. Studies included at least 5 patients with BE treated with cryotherapy via cryoballoon device and data extraction, which was performed by two investigators using standardized forms, included age, gender, length of BE segment, treatments prior to CbFAS, procedural time and number ablation sessions, technical feasibility, adverse events, and eradication rates of intestinal metaplasia (CE-IM) and dysplasia (CE-D) at follow-up. Quality of the studies was performed using a modified Newcastle Ottawa Scale. Random effects model was used in the presence of heterogeneity. RESULTS: Seven studies (4 full-length publications, 3 abstracts) met inclusion criteria for a total of 548 ablation sessions in 272 patients. In aggregate, the most common histopathology reported prior to cryoballoon ablation was high-grade dysplasia (n = 131), followed by low-grade dysplasia (n = 75), and intramucosal adenocarcinoma (n = 52). The pooled rate for technical feasibility, defined as completion of cryoablation as intended was 95.8% (95% CI: 93.6-97.5%; I2 = 13.2%; P = 0.3) (Figure 1a). The pooled rates of CE-IM and CE-D were 85.8% (95% CI: 77.8-92.2%, I2 = 55.5%; P = 0.04) and 93.8% (95% CI: 85.5-98.7%, I2 = 74.2%; P = 0.001) (Figure 1b,c), respectively. Funnel plots did not show substantial publication bias (Figure 2). The overall adverse event rate was 12.5% (34 out of 272 patients), of which stricture formation was the most common (5.8%), followed by mucosal laceration (0.7%), perforation (0.4%), and bleeding (0.4%). All adverse events were successfully managed endoscopically. CONCLUSION: This meta-analysis suggests that CbFAS has a comparable safety profile to radiofrequency ablation with a 12.5% adverse event rate. Furthermore, this study demonstrated that CbFAS is associated with high rates of CE-IM (88%) and CE-D (94%). Future prospective comparative trials are needed to corroborate these initial findings.