Aims:
Treatment of early Barrett's neoplasia currently consists of two steps: endoscopic resection (ER) of visible lesions with subsequent ablation of remaining Barrett's epithelium. However, extensive resection might hamper subsequent ablation due to stenosis. Combining both modalities in one session offers the potential advantages of preventing ablation in a strictured esophagus and reducing the number of treatments. Studies with ER and radiofrequency ablation (RFA) showed this strategy to be feasible, but unsafe. Cryoballoon ablation (CBA) differs from RFA in that it preserves the extracellular matrix which might protect the esophagus even with ablation deep into the esophageal wall. The aim of this study is to evaluate feasibility, safety and histopathological effects of single-step treatment with CBA and ER.
Methods:
Two single-step treatment regimens were evaluated in 3 pigs per regimen: 1) CRYO-ER: four adjacent cryoballoon ablations of 10 seconds followed by ER in the treated area; 2) ER-CRYO: ER followed by a 10-second ablation targeted on the ER wound. Primary outcomes were feasibility (technical success), and safety (perforations and clinically relevant strictures). Secondly, histopathological evaluation was performed of the CRYO-ER specimens and all esophageal resection specimens.
Results:
In total, 6 female pigs were treated (5 zones each) resulting in 15 areas per regimen. All ERs were technically successful. All pigs survived the aimed follow-up of 28 days. No perforations or clinically relevant stenosis occurred. Histopathological evaluation was feasible for all CRYO-ER specimens. Ablation effects were present throughout all layers of these specimens, while the architecture requisite for histopathological analysis remained intact. After 28 days, the esophageal specimens were evaluated for histopathological effects. For ER-CRYO, the submucosa was the deepest layer with post-treatment fibrosis and the muscularis propria for CRYO-ER (87% complete and 13% superficial involvement).
Conclusions:
Single-step treatment with limited endoscopic resection and cryoballoon ablation is feasible and safe in a porcine model and vindicates further evaluation in a clinical trial.
