title: Endoscopic radiofrequency ablation for Barrett's esophagus: 5-year outcomes from a prospective multicenter trial.
abstract: OBJECTIVE
  The AIM-II Trial included patients with nondysplastic Barrett's esophagus (NDBE) treated with radiofrequency ablation (RFA). Complete eradication of NDBE (complete response-intestinal metaplasia [CR-IM]) was achieved in 98.4 % of patients at 2.5 years. We report the proportion of patients demonstrating CR-IM at 5-year follow-up.
  
  
  METHODS
  Prospective, multicenter US trial (NCT00489268). After endoscopic RFA of NDBE up to 6 cm, patients with CR-IM at 2.5 years were eligible for longer-term follow-up. At 5 years, we obtained four-quadrant biopsies from every 1 cm of the original extent of Barrett's esophagus. All specimens were reviewed by one expert gastrointestinal pathologist, followed by focal RFA and repeat biopsy if NDBE was identified. Primary outcomes were (i) proportion of patients demonstrating CR-IM at 5-year biopsy, and (ii) proportion of patients demonstrating CR-IM at 5-year biopsy or after the single-session focal RFA.
  
  
  RESULTS
  Of 60 eligible patients, 50 consented to participate. Of 1473 esophageal specimens obtained at 5 years 85 % contained lamina propria or deeper tissue (per patient, mean 30 , standard deviation [SD] 13). CR-IM was demonstrated in 92 % (46 / 50) of patients, while 8 % (4 / 50) had focal NDBE; focal RFA converted all these to CR-IM. There were no buried glands, dysplasia, strictures, or serious adverse events. Kaplan-Meier CR-IM survival analysis showed probability of maintaining CR-IM for at least 4 years after first durable CR-IM was 0.91 (95 % confidence interval [CI] 0.77 - 0.97) and mean duration of CR-IM was 4.22 years (standard error [SE] 0.12).
  
  
  CONCLUSIONS
  In patients with NDBE treated with RFA, CR-IM was demonstrated in the majority of patients (92 %) at 5-year follow-up, biopsy depth was adequate to detect recurrence, and all failures (4 / 4, 100 %) were converted to CR-IM with single-session focal RFA.
authors.affiliation: Mayo Clinic, 13400 East Shea Boulevard, Scottsdale, AZ 85259, USA. Fleischer.David@mayo.edu
authors.forename: D E
authors.initials: DE
authors.lastname: Fleischer
authors.forename: B F
authors.initials: BF
authors.lastname: Overholt
authors.forename: V K
authors.initials: VK
authors.lastname: Sharma
authors.forename: A
authors.initials: A
authors.lastname: Reymunde
authors.forename: M B
authors.initials: MB
authors.lastname: Kimmey
authors.forename: R
authors.initials: R
authors.lastname: Chuttani
authors.forename: K J
authors.initials: KJ
authors.lastname: Chang
authors.forename: R
authors.initials: R
authors.lastname: Muthasamy
authors.forename: C J
authors.initials: CJ
authors.lastname: Lightdale
authors.forename: N
authors.initials: N
authors.lastname: Santiago
authors.forename: D K
authors.initials: DK
authors.lastname: Pleskow
authors.forename: P J
authors.initials: PJ
authors.lastname: Dean
authors.forename: K K
authors.initials: KK
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D001471:Barrett Esophagus / Q000473:pathology* / Q000601:surgery*; D001706:Biopsy / Q000379:methods; D017115:Catheter Ablation; D015331:Cohort Studies; D004947:Esophagus / Q000473:pathology* / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008679:Metaplasia / Q000601:surgery*; D008875:Middle Aged; D011446:Prospective Studies; D012008:Recurrence; D012086:Reoperation; D016879:Salvage Therapy; D018709:Statistics, Nonparametric; D016896:Treatment Outcome