Endoscopy in Barrett's esophagus. Surveillance during reflux management and new advances in the diagnosis and early detection of dysplasia.

Given the alarming rise in the incidence of esophageal cancer and the fact that Barrett's esophagus is clearly a precursor to this disease, effective surveillance is desirable. Endoscopic surveillance is recommended by major endoscopic and gastrointestinal societies based on the available data and hypothetic models suggest that the costs of endoscopic surveillance for Barrett's esophagus may be reasonable when compared with other commonly applied cancer screening strategies. Although, however, most implicated physicians agree that surveillance is warranted, recommended guidelines often are not followed. This occurrence may reflect the importance of some of the practical limitations inherent to carrying out intensive endoscopic biopsy protocols in large numbers of eligible patients. In an effort to improve the surveillance process, several new techniques have been tested and are in development. These techniques are aimed at facilitating the histologic sampling of larger areas of metaplastic epithelium, at better targeting sites more likely to harbor dysplasia and cancer, and at replacing endoscopic biopsies with nonhistologic tissue analysis. Although many of these newer techniques are promising, however, none are currently close to widespread clinical application. The current standard for surveillance remains the use of systematic endoscopic biopsies, with the frequency of surveillance endoscopies determined by the severity of any dysplastic changes that are found. Given the large number of patients that are likely to be eligible for screening and the current constraints in terms of physician availability and health-care resources, endoscopic biopsy will remain the cornerstone of Barrett's esophagus surveillance strategies unless newer alternatives are clearly advantageous in terms of accuracy, cost, availability, and ease of application. In the future, however, advances in techniques for minimally invasive ablation of Barrett's epithelium may make endoscopic surveillance obsolete altogether.