Low incidence of cancer and dysplasia in Barrett's esophagus
MedWire News: The risk for malignant progression in patients with Barrett's esophagus is lower than previously reported, research shows.
After a mean follow-up of 7 years, the incidence of esophageal, gastric cardia cancer, or high-grade dysplasia was 0.22% per year, according to researchers.
These data suggest that screening for esophageal adenocarcinoma in patients with Barrett's esophagus "may not be cost-effective," write Shivaram Bhat (Queen's University, Belfast, UK) and colleagues in the Journal of the National Cancer Institute.
The incidence of Barrett's esophagus is rising in the USA and Europe. Reports have shown the incidence of esophageal adenocarcinoma from Barrett's esophagus to range from 0% to 3.5% per year, with one US study using a stricter definition of Barrett's esophagus, suggesting the incidence of adenocarcinoma or high-grade dysplasia to be 0.38% per annum.
Noting that the cost-effectiveness of surveillance is dependent on the risk for progression of the condition to cancer, Bhat and colleagues followed-up 8522 patients with Barrett's esophagus included in a Northern Ireland registry between 1993 and 2005.
Barrett's esophagus was defined as columnar-lined epithelium of the esophagus with or without specialized intestinal metaplasia.
During follow-up, 79 patients were diagnosed with esophageal cancer, 16 with cancer of the gastric cardia, and 36 with high-grade dysplasia.
Overall, the risk for esophageal/gastric cancer or high-grade dysplasia was 0.22% per year.
The incidence of specialized intestinal metaplasia was observed in 46% of patients. Among these individuals, the combined incidence of cancer or dysplasia was 0.38% per year.
Individuals with specialized intestinal metaplasia at index biopsy were more than three times more likely to develop cancer or dysplasia than individuals without metaplasia (odds ratio [OR]=3.54). Men were also more likely to progress to cancer or dysplasia than women (OR=2.11).
The risk for progression to cancer or dysplasia did not differ over time, with the incidence in years 1 to 6 of follow-up 0.25% per year compared with 0.27% in years 6 to 11.
The researchers note that the UK definition of Barrett's esophagus does not require the presence of specialized intestinal metaplasia, whereas the US definition does.
In an editorial accompanying the study, Douglas Corley (Kaiser Permanente, Oakland, California, USA) said the study answers important questions, including whether patients with specialized intestinal metaplasia are at higher risk.
Future studies are needed to determine if surveillance or treatment reduces the risk for cancer or dysplasia over time. Also needed are better techniques for risk stratification, said Church.
By MedWire Reporters