Risk for esophageal adenocarcinoma with Barrett's esophagus may be lower than originally thought

Patients with Barrett's esophagus may have a lower risk for esophageal adenocarcinoma than originally thought, according to a new study.

Researchers in Denmark performed a national population-based cohort study to try to obtain accurate data on the incidence of esophageal adenocarcinoma and high-grade dysplasia in patients who have Barrett's esophagus. The study used Danish databases to collect information on all patients with Barrett's esophagus from 1999 through 2009. The main outcome measures were incidence rates for adenocarcinoma and high-grade dysplasia. The authors also calculated standardized incidence ratios using Danish cancer rates during the same time period to measure relative risk. The study results appear in the Oct. 13 New England Journal of Medicine.

Overall, 11,028 patients were found to have Barrett's esophagus (66.8% men vs. 33.2% women; median age at baseline, 62.7 years). The median follow-up time was 5.2 years. One hundred thirty-one patients were diagnosed with new adenocarcinoma in the first year after an index endoscopy and 66 new cases were diagnosed in subsequent years (incidence rate, 1.2 cases per 1,000 person-years; 95% CI, 0.9 to 1.5 per 1,000 person-years). Patients with Barrett's esophagus had a relative risk of 11.3 (95% CI, 8.8 to 14.4) for adenocarcinoma compared with the general population, while the annual risk was 0.12% (95% CI, 0.09 to 0.15). Patients with low-grade dysplasia on initial endoscopy were at higher risk for adenocarcinoma than patients without dysplasia.

The authors noted that more cases of Barrett's esophagus were diagnosed during the study period because of increased awareness and that it was difficult to classify all patients according to stage of dysplasia, among other limitations. However, they concluded that although Barrett's esophagus is a significant risk factor for esophageal adenocarcinoma, the absolute annual risk in this study was substantially lower than assumed in current guidelines for routine surveillance (0.12% vs. 0.5%). “The results of our study suggest that the risk of esophageal adenocarcinoma among patients with Barrett's esophagus is so minor that in the absence of dysplasia, routine surveillance of such patients is of doubtful value,” they wrote.

The author of an accompanying editorial agreed, pointing out that although endoscopy accurately detects Barrett's esophagus, the finding has become less significant as more is learned about its biological characteristics. “Currently available evidence has not shown that the current strategy of screening and surveillance of patients with Barrett's esophagus is cost-effective or reduces mortality from esophageal adenocarcinoma,” he wrote.