RecruitingDiagnostic testA Multicenter Prospective Cohort Study Comparing Random Biopsies Versus Wide-Area Transepithelial Brush-Sampling (WATS) for Surveillance of Barrett's Esophagus, the WATS-EURO2 StudyThe investigators aim to study the rate of developing a biopsy-based diagnosis of high-grade dysplasia (HGD) and EAC in BE patients in a prospective cohort of 208 BE patients at high risk of progression (i.e. after endoscopic removal of visible lesions containing HGD/EAC and/or a diagnosis of low-grade dysplasia (LGD)) as well as in 208 BE patients with a nondysplastic BE (NDBE) undergoing standard BE surveillance. In these patients the investigators will combine biopsy sampling with WATS at baseline and all follow-up endoscopies during a 3- year follow-up period. This will allow us to study the natural history of WATS-positive-biopsynegative- cases and of WATS-specific outcomes such as basal-crypt dysplasia. The study also allows us to collect specimens for future biomarker studies that may help to predict progression to HGD/EAC in the absence of morphological features of dysplasia.