Endoscopic radiofrequency ablation for Barrett's esophagus: 5-year outcomes from a prospective multicenter trial.

Background and study aims: The AIM-II Trial in- cluded 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 de- monstrating CR-IM at 5-year follow-up. Patients and methods: Prospective, multicenter US trial (NCT00489268). After endoscopic RFA of NDBE up to 6cm, 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 1cm 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 identi- fied. Primary outcomes were (i) proportion of pa- tients 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 ob- tained at 5 years 85% contained lamina propria or deeper tissue (per patient, mean 30 (13), standard deviation (SD) 13). CR-IM was demon- strated 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-Mei- er 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.