8. Barrett’s esophagus – A perfect target for cryo-ablation

Abstract

Endoscopic cryotherapy is used for a variety of indications in the gastrointestinal tract, including treatment of chronic gastric antral vascular ectasia (GAVE), radiation proctitis, and Barrett’s esophagus. Barrett’s esophagus (BE) is a known precursor to esophageal adenocarcinoma resulting from chronic gastroesophageal reflux disease. Endoscopic treatment of high grade neoplasia (high grade dysplasia) and early adenocarcinoma in Barrett’s esophagus is the preferred first line approach for most patients. This includes endoscopic mucosal resection (EMR) for nodular disease or focal neoplastic lesions, and mucosal ablation for flat neoplasia. Current ablative techniques include treatment with heat energy (such as radiofrequency ablation or RFA), cryogen (cryotherapy or cryoablation), and laser plus photosensitizing drug therapy (photodynamic therapy). Although less widely available and studied compared to RFA, endoscopic cryotherapy using liquid nitrogen or compressed gas such as carbon dioxide or nitrogen have excellent safety and efficacy profiles. The complete response rates for elimination of high grade neoplasia in Barrett’s esophagus are comparable to those of RFA, whether it is used for primary or salvage therapy. Cryotherapy can also be applied when RFA is contraindicated or associated with greater risk (such as in patients with esophageal strictures, radiation therapy, eosinophilic esophagitis, cardiac defibrillators, on chronic anti-platelet or anticoagulation therapy). Furthermore, a few studies of cryotherapy also demonstrate long term response rates for endoscopic treatment and palliation of esophageal adenocarcinoma, which cannot be treated with RFA. The incidence of side effects of cryotherapy, when used properly, is lower than that of RFA, particularly with less post-treatment pain and dysphagia. Patients can usually resume a normal diet, unlike RFA. Lastly, the current systems and cost of cryotherapy are significantly lower than that of RFA or photodynamic therapy. New methods of applying endoscopic cryotherapy are being developed to improve the portability and technical ease. Cryotherapy is an excellent mucosal ablative technique for the gastrointestinal tract.