Su1447 Prevalence and Natural History of Low-Grade Dysplasia in Patients With Barrett's Esophagus

Prevalence and Natural History of Low-Grade Dysplasia in Patients With Barrett’s Esophagus Christos Zavos*, Romy E. Verbeek, Max Leenders, Leon M. Moons, Frank P. Vleggaar, Peter D. Siersema Gastroenterology and Hepatology, UMC Utrecht, Utrecht, Netherlands Introduction: Previous studies have been inconsistent with regard to the prevalence of low-grade dysplasia (LGD) in patients with Barrett’s esophagus (BE) and the rate of progression of LGD to high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC). Aims: To assess the prevalence and natural history of LGD in patients with BE and LGD. Methods: All patients with a diagnosis of BE and LGD between 1985 and 2009 of whom pathology specimens were available in the nationwide pathology database (PALGA) were included and followed-up for progression to HGD and/or EAC. Median age at diagnosis and time to progression were assessed, as well as sex, p53 status and type of hospital where biopsies were taken. Patients were excluded if they had a prior diagnosis of HGD and/or EAC or if no follow-up endoscopic biopsies ( 3 months after the initial LGD diagnosis) were available. Results: In total, 10,152 diagnoses of BE were included in the database, of which 2,215 patients (21.8%) were diagnosed with LGD, mostly males (71.5%) with a median age of 62 years at diagnosis. A decreasing trend over time in LGD diagnoses as proportion of all BE diagnoses was observed using the Cochran-Armitage test (p 0.0001). At least one follow-up biopsy was available in 1,638 patients (73.9%). After a median follow-up of 6.7 years, 137 patients (8.4%) progressed to HGD and 72 (4.4%) progressed to EAC. Median time to progression to HGD was 8.42 (4.4113.62) years and to EAC was 8.28 (3.30-13.2) years. In 157 patients tested for p53 status, 104 (66.2%) were positive, of which 8 progressed to HGD and 3 to EAC. Of the patients having at least one follow-up biopsy, 213 (13.0%) had biopsies taken only at an academic hospital and 262 (16.0%) at both academic and nonacademic hospitals. Patients with biopsies coming from both academic, and academic and non-academic hospitals had a higher progression to HGD (53.3%) and EAC (33.3%) compared to non-academic hospitals. Conclusion: The prevalence of LGD in BE in a large cohort of patients with a diagnosis of BE is relatively high (21.8%), although the relative numbers of LGD are decreasing over time suggesting an increasing awareness for BE. Moreover, a considerable number of patients with LGD will develop HGD (8.4%) or EAC (4.4%) after a median follow-up of 6.7 years, demonstrating that endoscopic surveillance and/ or treatment should be considered in this subgroup of BE patients.