Radiofrequency vapor ablation for Barrett’s esophagus: feasibility, safety and proof of concept in a stepwise study with in vitro, animal, and the first in-human application

Abstract

Introduction The Radiofrequency Vapor Ablation (RFVA) System (AquaMedical, Inc., Santa Ana, CA) is a novel ablation system for eradication of Barrett’s esophagus, that generates vapor at 100 °C using an RF electrode located in the catheter tip. We performed in-vitro dosimetry studies and the first in-human feasibility study.

Methods The system includes an RFVA generator with syringe pump and a through-the-scope-catheter. The RFVA system was tested in-vitro (lean-beef and porcine study) and ablation depth was compared to focal RFA. Two doses were selected for further in-vivo testing in dysplatic BE patients. Repeat endoscopy with histology was performed after 8 weeks to assess squamous conversion.

Results In porcine, RFVA 3-seconds was comparable to RFA, whereas RFVA 5-seconds produced slightly deeper ablation. We selected a conservative 1-second and 3-seconds for human study. Fifty-three ablations were successfully applied in 15 patients with no adverse events. Follow-up endoscopy showed a median squamous conversion of 55 % (IQR 33 – 74) and 98 % (56 – 99) for 1 and 3-seconds, respectively.

Conclusions In this 3-phase study with lean-beef, porcine and the first in-human application, the RFVA system was feasible for esophageal ablation and successfully and safely converted targeted BE areas into squamous epithelium.

Publication History

Received: 31 July 2020
Received: 20 November 2020

Accepted: 20 November 2020

Accepted Manuscript online:
20 November 2020

Article published online:
18 February 2021

• References

• 1 Phoa KN, Pouw RE, Bisschops R. et al. Multimodality endoscopic eradication for neoplastic Barrett oesophagus: results of an European multicentre study (EURO-II). Gut 2016; 65: 555-562
• 2 Phoa KN, van Vilsteren FG, Weusten BL. et al. Radiofrequency ablation vs endoscopic surveillance for patients with Barrett esophagus and low-grade dysplasia: a randomized clinical trial. JAMA 2014; 311: 1209-1217
• 3 Weusten B, Bisschops R, Coron E. et al. Endoscopic management of Barrett's esophagus: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement. Endoscopy 2017; 49: 191-198
• 4 Shaheen NJ, Sharma P, Overholt BF. et al. Radiofrequency ablation in Barrett's esophagus with dysplasia. NEJM 2009; 360: 2277-2288
• 5 Phoa KN, Pouw RE, van Vilsteren FG. et al. Remission of Barrett's esophagus with early neoplasia 5 years after radiofrequency ablation with endoscopic resection: a Netherlands cohort study. Gastroenterology 2013; 145: 96-104
• 6 van Munster SN, Overwater A, Haidry R. et al. Focal cryoballoon versus radiofrequency ablation of dysplastic Barrett's esophagus: impact on treatment response and postprocedural pain. Gastrointest Endosc 2018; 88: 795-803 e2
• 7 McVary KT, Gange SN, Gittelman MC. et al. Minimally invasive prostate convective water vapor energy ablation: a multicenter, randomized, controlled study for the treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia. J Urol 2016; 195: 1529-1538
• 8 Gompelmann D, Shah PL, Valipour A. et al. Bronchoscopic thermal vapor ablation: best practice recommendations from an expert panel on endoscopic lung volume reduction. Respiration 2018; 95: 392-400
• 9 Thurkow A, Van Baal M, Van Eijndhoven H. Final results of a multicenter trial of safety and effectiveness of endometrial ablation with the AEGEA vapor system for the treatment of menorrhagia. J Minim Invasive Gynecol 2015; 22 (Suppl. 06) S46
• 10 Sharma P, Dent J, Armstrong D. et al. The development and validation of an endoscopic grading system for Barrett's esophagus: the Prague C & M criteria. Gastroenterology 2006; 131: 1392-1399
• 11 Saunders M, Dische S, Barrett A. et al. Continuous hyperfractionated accelerated radiotherapy (CHART) versus conventional radiotherapy in non-small-cell lung cancer: a randomised multicentre trial. CHART Steering Committee. Lancet 1997; 350: 161-165
• 12 Dunkin BJ, Martinez J, Bejarano PA. et al. Thin-layer ablation of human esophageal epithelium using a bipolar radiofrequency balloon device. Surg Endosc 2006; 20: 125-130
• 13 Fleischer DE, Sharma VK. Endoscopic ablation of Barrett's esophagus using the Halo system. Dig Dis 2008; 26: 280-284
• 14 DeMeester SR, Omar A, Bergman JJ. et al. Initial human experience with a novel through-the-scope cryoballoon device for mucosal ablation. Gastroenterology 2012; 142 (Suppl. 01) S1038
• 15 Herrero LA, van Vilsteren FG, Visser M. et al. Simultaneous use of endoscopic resection and radiofrequency ablation is not safe in an esophageal porcine model. Dis Esophagus 2015; 28: 25-31
• 16 van Vilsteren FG, Alvarez Herrero L, Pouw RE. et al. Predictive factors for initial treatment response after circumferential radiofrequency ablation for Barrett's esophagus with early neoplasia: a prospective multicenter study. Endoscopy 2013; 45: 516-525