CHICAGO — Radiofrequency ablation appears to provide a durable, safe, and complete eradication of dysplastic Barrett's esophagus in most patients.
Two years after undergoing radiofrequency ablation (RFA), 96% of patients with complete eradication of intestinal dysplasia at 1 year were still free of abnormal cells, Dr. Nicholas J. Shaheen said at the annual Digestive Disease Week.
Only 2 of the 50 patients analyzed experienced disease recurrence; both had relatively long lengths of high-grade dysplasia at baseline, which recurred as short lengths of low-grade dysplasia 2 years later, said Dr. Shaheen of the University of North Carolina at Chapel Hill.
Dr. Shaheen presented 2-year follow-up data from the Ablation of Intestinal Metaplasia Containing Dysplasia (AIM Dysplasia) trial. The study randomized 127 patients with dysplastic Barrett's esophagus in a 2:1 ratio to RFA or a sham procedure. Previously, 1-year data showed that the procedure completely eradicated dysplasia in 81% of those with high-grade dysplasia and in 90% of those with low-grade dysplasia. Overall, 77% of the ablation group had complete eradication (N. Engl. J. Med. 2009;360:2277-88).
Regardless of dysplasia level, the 84 patients who received ablation were significantly more likely than the 43 in the control group to have complete eradication of dysplasia, Dr. Shaheen reported.
The sham procedure was associated with eradication of intestinal dysplasia in 23% of patients who had low-grade dysplasia and 19% of those who had high-grade dysplasia. The patients in the control group were much more likely to show disease progression at 1 year (16%) than were the patients in the ablation group (4%), he said.
Among patients with low-grade dysplasia, 98% of the biopsy samples in the ablation group were free of intestinal metaplasia at 1 year, compared with 57% of biopsies in the control group. Similarly, among patients with high-grade dysplasia, 98% of the specimens from patients who underwent ablation were free of intestinal metaplasia at 1 year, compared with 59% of samples from control patients.
Patients who received the sham procedure were offered ablation after the first year of follow-up; all accepted. Currently, 119 patients have been treated.
The follow-up study reported at the meeting included 50 patients with complete eradication of dysplasia at 1 year and 2 full years of follow-up data. Low-grade dysplasia was present at baseline in 32 patients, high-grade in 18 patients. The mean age at baseline was 65 years; the mean length of Barrett's esophagus at baseline was 4 cm.
The procedure was considered very safe, Dr. Shaheen said. Of the four serious adverse events, three occurred in the first year (two cases of chest pain requiring admission; one gastrointestinal hemorrhage in a patient on antiplatelet therapy). During the second year, one more patient required admission for evaluation of chest pain.
Esophageal stricture developed in five patients during the first year and in four others during the second year. Six of the strictures developed after circumferential ablation and three after focal ablation. “Of note, three of these patients had a stricture prior to the procedure,” he said. All strictures were easily resolved with a median of 1.5 dilations.
In the overall intent-to-treat analysis, 92% of patients who had complete response at 1 year maintained complete response at 2 years. The rate was higher, at 96%, in the per-protocol analysis.
Among patients with high-grade dysplasia at baseline, 83% retained complete response (complete eradication of intestinal metaplasia) at 2 years in the intent-to-treat analysis; 88% did so in the per-protocol analysis. Among patients with low-grade dysplasia at baseline, 97% retained complete response in the intent-to-treat analysis, and 100% in the per-protocol analysis.
Only two patients showed disease progression, Dr. Shaheen reported. “One patient had a 6-cm length of high-grade dysplasia at baseline, and a 1-cm section of low-grade dysplasia at 2 years. The other had a 5-cm section of high-grade dysplasia at baseline, and a 0.5-cm length of low-grade dysplasia at the follow-up.”
Dr. Shaheen disclosed that he has received research grants from BÂRRX Medical, which sponsored the study and manufactures the endoscopic ablation system used in it. He has also received research funding and honoraria from numerous pharmaceutical companies.
Mary Ann Moon contributed to this report.
At 2 years, 96% of patients with a complete response to RFA at 1 year were still free of abnormal cells. DR. SHAHEEN