Radio-Frequency Ablation Shows Promise in Treating Barrett's Esophagus

A new outpatient procedure that allows doctors to treat precancerous changes in the esophagus with radiofrequency ablation (RFA) is showing promise.

Researchers at the University of North Carolina-Chapel Hill (UNC, USA) and other institutions conducting the Ablation of Intestinal Metaplasia (AIM) Dysplasia Trial--a multi-center trial of the RFA procedure--presented the interim results of the ongoing study that show that among patients treated with RFA, 85% were free of dysplasia, and 74% were free of all signs of Barrett's 12 months later. None of the treated patients progressed to high-grade dysplasia or cancer. In the control group, several patients got worse, and none were free of Barrett's. The interim study results were presented at the Digestive Disease Week annual meeting, held in San Diego (CA, USA) during May 2008.

In the procedure, the patient is sedated, and the gastroenterologist inserts a miniature camera, along with a sizing balloon, down the patient's esophagus. A second balloon delivers a short burst of energy that burns out the Barrett's tissue, which is identified by its rough and red appearance, in contrast to healthy pink tissue. The RFA procedure is usually repeated a few months later, with a smaller RFA device. The RFA procedures were performed with the HALO Ablation System, a product of BÂRRX Medical (Sunnyvale, CA, USA). The system consists of two different devices; the HALO360+ ablation catheter, capable of treating larger areas of circumferential Barrett's esophagus, and the HALO90 focal ablation device, used to treat smaller areas. Since Barrett's epithelium is approximately 500 µm in thickness, the HALO energy generator and the ablation catheter electrode array are designed to work in concert to achieve a uniform, superficial depth of ablation of ~1,000 µm.

"It's like removing old wallpaper -- you do a big stripping and then go back and remove any bits that are left,” said Charles Lightdale, M.D., a gastroenterologist at New York-Presbyterian Hospital/Columbia (NY, USA), who also consults for BÂRRX.

"It's way cool. It's far and away the most effective endoscopic treatment that we've ever had,” said AIM study presenter Nicholas Shaheen, M.D., M Ph., director of the center for esophageal disease and swallowing at UNC. "This is very safe and effective therapy, but as we move from high-risk to lower-risk patients, the calculus changes.”

The AIM study has a planned enrollment of 120 patients diagnosed with Barrett's esophagus with dysplasia--either low-grade or high-grade--at 16 U.S. medical centers. The randomized, sham-controlled trial assigned patients in a 2:1 ratio to receive either an endoscopic ablation procedure using the HALO360 System or a similar procedure in which no ablation is delivered (sham). Patients are not aware of which procedure they receive and undergo follow-up with endoscopy and biopsy over the ensuing 12 months with comparison of the treatment results at each time interval. All patients received esomeprazole magnesium as therapy for acid reflux disease as part of the study protocol.


Related Links:
University of North Carolina-Chapel Hill
BÂRRX Medical