Preoperative prevalence of Barrett's esophagus in esophageal adenocarcinoma: a systematic review.

Background & Aims: The public health impact of past screening and surveillance practices on the outcomes of Barrett's related cancers has not previously been quantified. Our purpose was to determine the prior prevalence of Barrett's esophagus in reported cases of incident adenocarcinoma undergoing resection, as an indirect measure of impact.

Methods: We performed a systematic review of the literature from 1966 to 2000. Studies were included if they reported: (1) the number of consecutive adenocarcinomas resected, and (2) the number of those resected who had a previously known diagnosis of Barrett's. We generated summary estimates using a random effects model.

Results: We identified and reviewed 752 studies. Twelve studies representing a total of 1503 unique cases of resected adenocarcinomas met inclusion criteria. Using a random effects model, the overall percentage of patients undergoing resection who had a prior diagnosis of Barrett's was 4.7% +/- 2.9%.

Conclusions: The low prior prevalence (approximately 5%) of Barrett's esophagus in this study population provides indirect evidence to suggest that recent efforts to identify patients with Barrett's-whether through endoscopic screening or evaluation of symptomatic patients-have had minimal public health impact on esophageal adenocarcinoma outcomes. The potential benefits of endoscopic surveillance seem to have been limited to only a fraction of those individuals at risk. These data thus provide a clear and compelling rationale for the development of effective screening strategies to identify patients with Barrett's esophagus.