Endoscopic applications of cryospray ablation therapy-from Barrett's esophagus and beyond

Abstract

In the last decade, the treatment of dysplastic Barrett's esophagus has evolved into primarily endoscopic therapy. Many techniques have become well-established to destroy or remove the mucosal lining of Barrett's esophagus. One of the newest therapies, cryospray ablation, has become a modality to treat both dysplastic Barrett's esophagus as well as esophageal carcinoma. In endoscopic applications, the cryogen used is either liquid nitrogen or carbon dioxide which causes tissue destruction through rapid freeze-thaw cycles. Unlike other endoscopic ablation techniques, its unique mechanism of action and depth of tissue injury allow cryoablation to be used effectively in flat or nodular disease. It can be combined with other modalities such as endoscopic mucosal resection or radiofrequency ablation. Its esophageal applications stem well-beyond Barrett's into ablation of early carcinoma, palliative debulking of advanced carcinoma and reduction of tumor ingrowth into stents placed for dysphagia. Although there are fewer reported studies of endoscopic cryoablation in the literature compared to other endoscopic ablation methods, emerging research continues to demonstrate its efficacy as a durable ablation technology with a variety of applications. The aim of this review is to examine the pathophysiology of endoscopic cryospray ablation, describe its outcomes in Barrett's with dysplasia and esophageal carcinoma, and examine its role in other gastrointestinal applications such as hemostasis in the stomach and rectum.

Keywords: Barrett’s esophagus; Cryotherapy; Dysplasia; Endoscopic cryoablation; Esophageal carcinoma.

Figure 1

Decompression catheter placement for liquid nitrogen cryospray.

Figure 2

Results that are equal to the outcomes of radiofrequency ablation. A: Barrett’s esophagus with high grade dysplasia; B: Liquid nitrogen cryospray ablation; C: Complete eradication of dysplasia and intestinal metaplasia.

Figure 3

Endoscopic mucosal resection following liquid nitrogen cryoablation.

Figure 4

Debulking of esophageal cancer for palliation of swallowing. A: Bulky friable esophageal adenocarcinoma causing dysphagia and bleeding; B: Liquid nitrogen cryospray ablation of tumor for palliation; C: Post-ablation appearance of tumor at 8 wk.