A study led by Dr Nicholas Shaheen of the University of North Carolina was published on the 28th of May in The New England Journal of Medicine.
“Radiofrequency Ablation in Barrett’s Esophagus with Dysplasia” used subjects suffering from Barrett’s Oesophagus, a condition associated with an increased risk of developing cancer of the oesophagus. Complete eradication occurred in 81% of the subjects with high grade dysplasia (abnormal development of cells) following treatment, compared with just 19% of the control subjects.
People who suffer repeatedly from Gastro-oesophageal Reflux Disease, commonly known as acid reflux, are in danger of developing Barrett’s Oesophagus. The oesophagus connects the throat to the stomach, and the condition occurs when the cells lining the oesophagus start to be replaced by intestinal lining cells. Once developed the risk of it further progressing into cancer increases by about 0.5% each year for the patient; if the degree of dysplasia is high then the risk is closer to 10% each year.
If a patient does have a cancerous tumour, their chance of surviving beyond five years is less than 15%. It is one of the least common cancers with annual deaths in the US at about 14,000, but the rate of incidence for Barrett’s Oesophagus has been steadily increasing over the last decade in western nations due in part to their diet. Using patient data between 1996 and 2003, the Erasmus University Medical Centre in Rotterdam found a rate of incidence increase from 14.3 per 100,000 patients in 1997, to 23.1 per 100,000 in 2002.
Results of the study
Of the subjects who did receive radio wave heat treatment to burn suspicious cells, 1.2% developed oesophageal cancer as opposed to 9.3% of those who received placebo treatment instead. Total eradication rate for subjects with low grade dysplasia was 90.5% of patients compared with 22.7% of the control group. Side effects of the treatment included five incidents of stricture and more commonly chest pains. All 127 patients included in the study were candidates for surgery but the study did not include alternative treatments.
Despite the obvious limitations of the study all the results were found to be highly significant. Dr Shaheen said in a telephone interview that “the study was really designed to look to see if we could get rid of the Barrett’s, not to look and see if we could get rid of the cancer,” but that “this may be a way to decrease the chance of cancer in these patients.”
Although the study didn’t compare alternate treatments, for patients with high grade dysplasia, the only option is an oesophagectomy where the oesophagus is removed. This so far has been the only method known to remove all pre-cancerous cells. Approximately a third of patients with high grade dysplasia will already have cancerous cells and progression to cancer is common. The study therefore provides an alternative treatment option for these patients.
Dr Jacques Bergman of Academic Medical Centre Amsterdam wrote a commentary on the study, “Radiofrequency Ablation – Great for Some or Justified for Many?” In it he said that the results are better than those of alternative therapies currently being used, such as surgery or photodynamic therapy (a two-part chemical and laser treatment), and he suggests that “surgery for high-grade dysplasia should no longer be offered routinely.”