title: Risk of malignant progression in Barrett's esophagus patients: results from a large population-based study.
abstract: BACKGROUND
  Barrett's esophagus (BE) is a premalignant lesion that predisposes to esophageal adenocarcinoma. However, the reported incidence of esophageal adenocarcinoma in patients with BE varies widely. We examined the risk of malignant progression in patients with BE using data from the Northern Ireland Barrett's esophagus Register (NIBR), one of the largest population-based registries of BE worldwide, which includes every adult diagnosed with BE in Northern Ireland between 1993 and 2005.
  
  
  METHODS
  We followed 8522 patients with BE, defined as columnar lined epithelium of the esophagus with or without specialized intestinal metaplasia (SIM), until the end of 2008. Patients with incident adenocarcinomas of the esophagus or gastric cardia or with high-grade dysplasia of the esophagus were identified by matching the NIBR with the Northern Ireland Cancer Registry, and deaths were identified by matching with records from the Registrar General's Office. Incidence of cancer outcomes or high-grade dysplasia was calculated as events per 100 person-years (% per year) of follow-up, and Cox proportional hazard models were used to determine incidence by age, sex, length of BE segment, presence of SIM, macroscopic BE, or low-grade dysplasia. All P values were from two-sided tests.
  
  
  RESULTS
  After a mean of 7.0 years of follow-up, 79 patients were diagnosed with esophageal cancer, 16 with cancer of the gastric cardia, and 36 with high-grade dysplasia. In the entire cohort, incidence of esophageal or gastric cardia cancer or high-grade dysplasia combined was 0.22% per year (95% confidence interval [CI] = 0.19% to 0.26%). SIM was found in 46.0% of patients. In patients with SIM, the combined incidence was 0.38% per year (95% CI = 0.31 to 0.46%). The risk of cancer was statistically significantly elevated in patients with vs without SIM at index biopsy (0.38% per year vs 0.07% per year; hazard ratio [HR] = 3.54, 95% CI = 2.09 to 6.00, P < .001), in men compared with women (0.28% per year vs 0.13% per year; HR = 2.11, 95% CI = 1.41 to 3.16, P < .001), and in patients with low-grade dysplasia compared with no dysplasia (1.40% per year vs 0.17% per year; HR = 5.67, 95% CI = 3.77 to 8.53, P < .001).
  
  
  CONCLUSIONS
  We found the risk of malignant progression among patients with BE to be lower than previously reported, suggesting that currently recommended surveillance strategies may not be cost-effective.
authors.affiliation: Centre for Public Health, Queens University Belfast, Institute of Clinical Sciences Building, Belfast BT12 6BA, Northern Ireland, UK. shiv_bhat@doctors.org.uk
authors.forename: Shivaram
authors.initials: S
authors.lastname: Bhat
authors.forename: Helen G
authors.initials: HG
authors.lastname: Coleman
authors.forename: Fouad
authors.initials: F
authors.lastname: Yousef
authors.forename: Brian T
authors.initials: BT
authors.lastname: Johnston
authors.forename: Damian T
authors.initials: DT
authors.lastname: McManus
authors.forename: Anna T
authors.initials: AT
authors.lastname: Gavin
authors.forename: Liam J
authors.initials: LJ
authors.lastname: Murray
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality; D000368:Aged; D000369:Aged, 80 and over; D001471:Barrett Esophagus / Q000150:complications / Q000453:epidemiology* / Q000401:mortality / Q000473:pathology; D002299:Cardia; D002471:Cell Transformation, Neoplastic / Q000473:pathology*; D018450:Disease Progression; D004938:Esophageal Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality; D005260:Female; D006801:Humans; D015994:Incidence; D007422:Intestines / Q000473:pathology; D053208:Kaplan-Meier Estimate; D008297:Male; D008679:Metaplasia / Q000453:epidemiology; D008875:Middle Aged; D009660:Northern Ireland / Q000453:epidemiology; D011230:Precancerous Conditions / Q000453:epidemiology* / Q000473:pathology; D016016:Proportional Hazards Models; D012042:Registries; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality