Characteristics and Neoplastic Progression in Barrett’s Esophagus: A Large Population-Based Study from Iceland

<b>Background:</b> Barrett's esophagus (BE) is a known precursor to esophageal adenocarcinoma (EAC). However, reports on incidence and progression-to-neoplasm rates have been very variable and conflicting. The aims of the study were to evaluate the characteristics of BE and its progression to neoplasm in a large homogeneous population. <b>Methods:</b> This was a retrospective population-based study with patients identified from 11 institutions through the databases in two centralized pathology laboratories. Demographics and relevant clinicopathological features were obtained from medical records among patients with a pathologically confirmed BE by the presence of intestinal metaplasia between 2003 and 2022. <b>Results:</b> A total of 1388 patients were identified with BE: 948 were men (69%); the median age at diagnosis was 62 years (IQR, 53-72). The ratio of long-segment BE to short-segment BE was significantly higher in patients ≥ 60 years (1.15, 284/248) than those ≤ 60 years (0.77, 205/265) (<i>p</i> = 0.0025). At BE diagnosis, 9.4% had neoplasms: LGD (<i>n</i> = 65), HGD (<i>n</i> = 16), and EAC (<i>n</i> = 49). Among 1258 non-dysplastic BE (NDBE) patients, 4.6% developed a neoplasm-LGD (<i>n</i> = 35), HGD (<i>n</i> = 8), and EAC (<i>n</i> = 15)-with a median observation-period of 5 years (IQR, 3-7). Overall, 160 cases with neoplasms were diagnosed in this BE cohort; 130 (74%) were present at initial BE diagnosis, and 58 (26%) progressed to neoplasms from NDBE. <b>Conclusions:</b> The ratio of long-segment BE was found to be significantly higher in patients ≥ 60 years. Around 9% of the patients were diagnosed as harboring a neoplasm concomitantly with BE, accounting for approximately 74% of all neoplasms. After a median follow-up of 5 years, about 5% of BE showed dysplastic or malignant progression.