Radiofrequency Ablation (RFA) – Barrx
One of the newer treatments for Barrett’s esophagus with dysplasia is radiofrequency ablation, also sometimes referred to as Barrx (the name of the company), or Halo (the name of the specific treatment). Several people have asked questions about Barrx, so here’s some information.
How it works
Halo 360 – Upper endoscopy is performed and the length of the Barrett’s esophagus is measured. A special ‘sizing balloon’ is used to figure out the width of the esophagus where the BE is located. Once the diameter of the esophagus is known, a special catheter with the ablation balloon on it is passed into the esophagus. There are 3 cm of electrodes on the balloon which are placed in the area of the BE to be treated. When the balloon is inflated, the electrodes touch the wall of the esophagus and energy is released. The release of the energy creates a shallow burn, which destroys the Barrett’s esophagus without harming the tissue underneath. The treated area is then gently cleaned with a plastic cap on the end of the endoscope to remove any loose tissue. Then the BE is treated a second time with the RFA balloon.
Circumferential RFA is most often performed with longer BE, particularly when the BE is present on all the walls of the esophagus.
Halo 90 – A small device that looks like a paddle (about 2 cm by 1 cm in size) is placed on the end of a regular endoscope. An upper endoscopy is then performed and the paddle is placed on areas of BE that to be treated. The endoscopist then steps on a pedal, and energy is released, making a shallow burn in the area. Each area of BE is treated twice, then the mucosa is cleaned with the paddle. The same areas are then treated 2 more times with the Halo90 during the same procedure.
Halo90 is typically used in patients with small amounts of BE, such as tongues or islands of Barrett’s.
Chest discomfort may occur after the procedure. Other possible complications include lacerations of the esophageal mucosa, which is like a shallow tear or cut which may bleed. Some patients have had difficulty swallowing after the procedure and rarely patients will develop a stricture that needs dilation with a special balloon. Perforation, or tearing the wall of the esophagus, is a risk, but so far no studies have been published showing a perforation during RFA.
There is alot of interest in ablation of Barrett’s esophagus and several ongoing research studies. Here are a few of the published studies using RFA in dysplasia:
At Digestive Disease Week 2008, an international gastroenterology meeting, the interim results for a randomized, multicenter, sham-controlled trial of RFA were presented. All the patients in the study had BE with HGD or LGD. The patients were randomized (randomly assigned) to either RFA or a sham (fake) RFA. Halo 360 and Halo 90 were performed to treat the BE and dysplasia.
At the time of the presentation in May 2008, 127 patients had been treated. The average number of sessions needed to treat BE with dysplasia was 3.5. 67% of patients with HGD had complete eradication of dysplasia compared to no patients who received the sham treatment. 96% of patients with LGD had complete eradication of dysplasia with RFA. Looking at complete eradication of the BE, 60% of patients with HGD and 83% of patients with LGD had no BE left after treatment with RFA. 1 patient had a stricture treated with dilation and there were no esophageal perforations. The study’s expected completion date was summer 2008, so complete results should be available soon. (1)
A US Multicenter registry study of RFA was published in July 2008, which looked back at the records of 142 patients with BE-HGD at 16 different academic hospitals. RFA was performed in all the patients using the Halo360. In this study, patients had 1 to 2 ablation sessions. 2 patients had HGD after ablation. Of the patients in the study who had follow up biopsies, complete eradication of HGD was seen in 90% of patient. Complete eradication of all dysplasia (including LGD) was seen in 81%. Complete eradication of all Barrett’s esophagus occurred in 54% of patients. One patient in the study developed an esophageal stricture (narrowing) which was treated with esophageal dilation. (2)
Another study looked at RFA in patients with early cancer, high grade dysplasia (HGD), or low grade dysplasia (LGD). 44 patients were in the study and 31 patients had endoscopic mucosal resection (EMR) of nodular BE. The patients then had ablation of the remaining BE using the Halo360 or Halo90 system. At the end of the study, the BE and dysplasia was completely gone in 98% of the patients (43 of 44). Follow up at 21 months showed no recurrence of dysplasia in the patients. (3)
Who Should Consider RFA?
Most of the research done with RFA has been targeted to patients with Barrett’s esophagus and dysplasia. The response to treatment is very good in most of the studies, and is a reasonable option to consider for treatment. For patients without dysplasia, the use of RFA is not as clear, which will be addressed in a separate post.
Here are the references for the 3 studies discussed above:
- Shaheen NJ, Sharma P, Overholt BF, et al. A randomized, multicenter, sham-controlled trial of radiofrequency ablation for subjects with Barrett’s esophagus containing dysplasia: interim results of the AIM dysplasia trial. Gastroenterology, Volume 134, Issue 4, Supplement 1, April 2008, Pages A-37
- Ganz RA, Overholt BF, Sharma VK, et al. Circumferential ablation of Barrett’s esophagus, that contains high-grade dysplasia: a U.S. multicenter registry. Gastrointestinal Endoscopy 2008, vol 68(1), pp 35-40.
- Pouw RE, Gondrie JJ, et al. Eradication of Barrett’s esophagus with early neoplasia by radiofrequency ablation, with or without endoscopic resection. J Gastrointest Surg 2008, vol 12, pp 1627-37.