title: Safety and efficacy of carbon dioxide cryotherapy for treatment of neoplastic Barrett's esophagus.
abstract: OBJECTIVE
  Endoscopic cryotherapy has been used successfully for the ablation of Barrett's esophagus but outcome data are limited. The aim of this study was to assess the long-term safety and efficacy of carbon dioxide (CO2) cryotherapy as primary or rescue treatment for Barrett's esophagus with high grade dysplasia (HGD) or neoplasia.
  
  
  METHODS
  This was a retrospective, single-center, nonrandomized study carried out in an academic, tertiary care center and affiliated community hospital. A total of 78 patients with neoplastic Barrett's esophagus who had not undergone previous ablation (treatment-naïve group) or who had persistent or recurrent neoplasia despite previous treatment (rescue treatment group) were enrolled. Visible Barrett's lesions, when present, were removed by endoscopic mucosal resection, which was followed by CO2 cryotherapy until neoplasia had been eradicated, or intervening therapy was necessary, or treatment was considered to have failed. Surveillance biopsies were obtained at standard intervals. Rates of complete response for cancer, HGD, and intestinal metaplasia were calculated. Treatment failure, recurrence, adverse events, progression, and mortality were also recorded.
  
  
  RESULTS
  Between 2006 and 2013, 64 evaluable patients (20 treatment naïve, 44 rescue treatment) were treated and followed up (median time 4.2 years). At 1 year, the overall complete response rates were 77 % for cancer (10/13), 89 % for dysplasia 57/64), 94 % for HGD (60/64; 100 % for treatment naïve, 91 % for rescue treatment), and 55 % for intestinal metaplasia (35/64). Long-term complete response for neoplasia with rescue therapy was 87 % (56/64). Disease-specific mortality was 1/68 (2 %). Treatment failed to eradicate neoplasia in four patients (6 %) (all in the rescue group). Recurrent or new intestinal metaplasia was detected in 20/64 (31 %) after two negative follow-up procedures. Serious adverse events were noted in two patients (3 %). Post-cryotherapy pain occurred in four patients (6 %; only two needed analgesics). No bleeding or new strictures were noted. Buried Barrett's was detected in 5/68 patients (7 %).
  
  
  CONCLUSIONS
  CO2 cryotherapy was a safe and effective primary curative or rescue therapy for Barrett's neoplasia.
authors.affiliation: Division of Gastroenterology, Department of Medicine, The Johns Hopkins Medical Institutions, Baltimore, Maryland, United States.
authors.forename: Marcia Irene
authors.initials: MI
authors.lastname: Canto
authors.affiliation: Division of Gastroenterology, Department of Medicine, The Johns Hopkins Medical Institutions, Baltimore, Maryland, United States.
authors.forename: Eun Ji
authors.initials: EJ
authors.lastname: Shin
authors.forename: Mouen A
authors.initials: MA
authors.lastname: Khashab
authors.affiliation: Division of Gastroenterology, Department of Medicine, The Johns Hopkins Medical Institutions, Baltimore, Maryland, United States.
authors.forename: Mouen
authors.initials: M
authors.lastname: Khashab
authors.affiliation: Department of Surgery, The Johns Hopkins Medical Institutions, Baltimore, Maryland, United States.
authors.forename: Daniela
authors.initials: D
authors.lastname: Molena
authors.affiliation: Division of Gastroenterology, Department of Medicine, The Johns Hopkins Medical Institutions, Baltimore, Maryland, United States.
authors.forename: Patrick
authors.initials: P
authors.lastname: Okolo
authors.affiliation: Department of Pathology, The Johns Hopkins Medical Institutions, Baltimore, Maryland, United States.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Montgomery
authors.affiliation: Division of Gastroenterology, Department of Medicine, The Johns Hopkins Medical Institutions, Baltimore, Maryland, United States.
authors.forename: Pankaj
authors.initials: P
authors.lastname: Pasricha
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001471:Barrett Esophagus / Q000473:pathology / Q000601:surgery*; D002245:Carbon Dioxide / Q000627:therapeutic use*; D003452:Cryosurgery / Q000379:methods*; D004938:Esophageal Neoplasms / Q000473:pathology / Q000601:surgery*; D004945:Esophagoscopy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011230:Precancerous Conditions / Q000473:pathology / Q000601:surgery*; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D002245:Carbon Dioxide