A procedure that uses heat generated by radio waves to treat Barrett's esophagus, a condition caused by acid reflux (severe heartburn), can eliminate signs of the potentially cancer-causing disorder and reduce the risk that the disease will progress.
Findings from the first multicenter trial of the procedure, called radiofrequency ablation, could mean patients have an alternative to surgery for treating Barrett's esophagus. The procedure uses a scope inserted through the mouth to destroy the abnormal tissue. The investigators report their findings in the May 28 issue of the New England Journal of Medicine.
"Patients with Barrett's esophagus can go on to develop esophageal cancer," says Steven A. Edmundowicz, M.D., lead investigator at the study site at Washington University School of Medicine in St. Louis. "Cancer of the esophagus usually is deadly. Less than 15 percent of patients with esophageal adenocarcinoma survive for five years, and in those with advanced Barrett's esophagus, the risk that the condition will advance to become cancer is about 6 percent per year."
In Barrett's esophagus, part of the lining of the esophagus is replaced with cells that resemble intestinal cells. As the condition progresses, these cells become increasingly disordered. Long-standing acid reflux disease is common in those who develop Barrett's esophagus, which affects about 1 percent of adults in the United States.
A total of 127 patients at 19 sites took part in the study, which used endoscopes to diagnose the disease and then to deliver radiofrequency ablation to the abnormal lining of the esophagus. The technique heats the abnormal tissue to destroy it while leaving the deeper layers of the esophagus undamaged.
All patients in the study had the disordered, cellular growth called dysplasia associated with more advanced Barrett's esophagus. Patients were classified as having either low-grade dysplasia or high-grade dysplasia. Regardless of how they were classified for the study, patients received the anti-reflux medication esomeprazole (Nexium), to keep their reflux disease in check as much as possible.
Led by Nicholas J. Shaheen, M.D., at the University of North Carolina at Chapel Hill, the investigators at the various study sites randomly selected patients to either receive radiofrequency ablation or to undergo a sham procedure in which endoscopes were inserted through the mouth and the lining of the esophagus was examined, but no radio waves were delivered.
Two patients received the actual treatment for every one who got a sham procedure. Those who received the ablation treatment could get up to four treatments during the 12 months of the study. Following the study period, those who had not received ablation therapy were given the option of getting the treatment.
In the patients who had the treatment, dysplasia disappeared in just over 90 percent of patients with low-grade disease and in more than 80 percent of those with high-grade disease compared to about 23 percent of the low-grade patients and 19 percent of the high-grade patients who had sham procedures rather than the ablation therapy. In 78 percent of treated patients, not only did dysplasia disappear, but all the abnormal intestinal-type cells were eliminated as well.
"During the 12-month study period, we detected fewer cancers in the ablation group than in the control group," says Edmundowicz, a professor of medicine in the Division of Gastroenterology. "But because cancers occurred in a total of only five study patients, the numbers are not as powerful regarding cancer as they are regarding eradication of Barrett's esophagus."
The risk of progressing from Barrett's esophagus to esophageal cancer is approximately 1 percent for those with low-grade dysplasia and 6 percent for those with high-grade disease.
"From these short term results, it appears we may have another useful tool in our treatment arsenal," says Edmundowicz, who is a staff physician at Barnes-Jewish Hospital and a gastroenterologist at the Siteman Cancer Center. "Additional follow-up will be necessary to demonstrate the true effectiveness of radiofrequency ablation in preventing esophageal cancer in patients with Barrett's esophagus. "
Most study subjects tolerated the treatments very well, he says. "The one side effect that most ablation patients experienced was soreness in the chest following therapy, this was easily managed with medications, and they were less sore than if they had surgery, which has been the primary treatment option," he says.
The surgical option is offered to patients with Barrett's esophagus found to have severe dysplasia or cancer. The type of surgery varies, but it usually involves removing most of the esophagus, pulling a portion of the stomach up into the chest and attaching it to what remains of the esophagus.
The study was supported by BARRX Medical, which manufactures the ablation device. All patients in the study also received the anti-reflux drug. Edmundowicz has received lecture support from BARRX Medical. Other disclosures for study investigators are listed in the article in the New England Journal of Medicine.
Shaheen NJ, et al. Radiofrequency ablation in Barrett's esophagus with dysplasia. New England Journal of Medicine, vol 330 (22), May 28, 2009.
This study was supported by BARRX Medical. Study medication was provided by AstraZeneca. Statistical analysis and data management were supported by a grant from the National Institutes of Health.