Clinical Question: What is the risk of adenocarcinoma developing in patients with Barrett’s esophagus?
Background: The risk of esophageal adenocarcinoma has increased by a factor of six over the last 25 years. Risk factors include white race, male gender, old age and Barrett’s metaplasia of the distal esophagus. This has justified endoscopic surveillance even in nondysplastic Barrett’s based on the risk of developing cancer. However, 95 percent of patients with a new diagnosis of adenocarcinoma do not have a previous diagnosis of Barrett’s. Hence, the relevance of screening and surveillance programs is questioned in this paper.
Study design: A cohort study was conducted of the entire Danish population of 5.4 million people. The Danish Pathology Registry contains pathology reports and other information regarding all biopsy specimens examined at all hospitals and by all private practitioners in Denmark. The aim was to calculate the incidence of adenocarcinoma or high-grade dysplasia among patients with low-grade dysplasia in Barrett’s esophagus.
Statistical analysis: The incidence rates (cases per 1,000 person-years) for the three endpoints of high-grade dysplasia, esophageal adenocarcinoma and the combined endpoint of adenocarcinoma or high-grade dysplasia were calculated among patients who had received a diagnosis of Barrett’s esophagus and in the general population. Incidence rates with 95 percent confidence intervals were calculated for all endpoints.
Results: Incidence rate for adenocarcinoma is 1.2 cases per 1,000 person-years (95% confidence interval [CI], 0.9 to 1.5). As compared with the risk in the general population, the relative risk of adenocarcinoma among patients with Barrett’s esophagus was 11.3 (95% CI, 8.8 to 14.4). Detection of low-grade dysplasia on the index endoscopy was associated with an incidence rate for adenocarcinoma of 5.1 cases per 1,000 person-years. In contrast, the incidence rate among patients without dysplasia was 1.0 case per 1,000 person-years.
Synopsis: The main finding of this large, population-based study was that the absolute annual risk of esophageal adenocarcinoma after a diagnosis of Barrett’s esophagus was several times lower (0.12%) than the risk reported in previous studies (0.5%).
Bottom line: The results of this 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. This paper should lead us to question the need for surveillance endoscopy.
Reference: Hvid-Jensen F, Pedersen L, Drewes AM, et al. Incidence of adenocarcinoma among patients with Barrett’s esophagus. N Engl J Med. 2011;365(15):1375-1383.