title: Circumferential location predicts the risk of high-grade dysplasia and early adenocarcinoma in short-segment Barrett's esophagus.
abstract: BACKGROUND
  Whether early Barrett's neoplasia has a predilection for particular spatial locations in shorter segment disease is currently unknown. Anatomic factors may play a role in lesion location because of differing levels of mucosal acid exposure.
  
  
  OBJECTIVE
  To identify high-risk lesion locations, which has important implications for surveillance strategies.
  
  
  METHODS
  We interrogated a prospectively maintained database of patients who underwent endoscopic resection (ER) for Barrett's neoplasia at 2 Australian tertiary centers. Lesions targeted for ER were characterized and their location in the distal esophagus was noted as on a clock face. A Z test of proportions was used to test for deviation from uniformity in the distribution of lesions.
  
  
  METHODS
  Two Australian tertiary centers.
  
  
  METHODS
  Patients who underwent ER for Barrett's neoplasia.
  
  
  METHODS
  Lesion location in the distal oesophagus, resected specimen histology.
  
  
  RESULTS
  A total of 146 consecutive patients had ER for biopsy-proven high-grade dysplasia or esophageal adenocarcinoma. A total of 75 patients had Barrett's segment length of 5 cm or less and a visible lesion. Five patients had 2 visible lesions giving a total of 80 lesions. ER of 66 lesions (82.5%) led to the identification of advanced pathology: 37 high-grade dysplasia (46%), 24 mucosal adenocarcinoma (30%), 5 submucosal adenocarcinoma (6%). Of a total of 80 lesions, 43 (53.8%) (95% CI, 42.9%-64.7%) were centered within the 2- to 5-o'clock arc, comprising 25% of the circumference. This area also accounted for 36 (54.5%) of the 66 lesions with advanced histology (95% CI, 42.5%-66.5%). All confidence intervals lie wholly above the 25% expected in a uniform circular distribution (P < .05).
  
  
  CONCLUSIONS
  Observational study in a tertiary center.
  
  
  CONCLUSIONS
  In Barrett's maximal segments of 5 cm or less, the 2- to 5-o'clock arc, accounts for approximately 50% of macroscopically visible lesions and associated early neoplasia. This finding has important implications for surveillance strategies.
authors.affiliation: Department of Gastroenterology and Hepatology, Westmead Hospital, Sydney, Australia.
authors.forename: Viraj C
authors.initials: VC
authors.lastname: Kariyawasam
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Bourke
authors.forename: Luke F
authors.initials: LF
authors.lastname: Hourigan
authors.forename: Gary
authors.initials: G
authors.lastname: Lim
authors.forename: Alan
authors.initials: A
authors.lastname: Moss
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Williams
authors.forename: Scott B
authors.initials: SB
authors.lastname: Fanning
authors.forename: Adrian M
authors.initials: AM
authors.lastname: Chung
authors.forename: Karen
authors.initials: K
authors.lastname: Byth
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001471:Barrett Esophagus / Q000473:pathology* / Q000601:surgery; D002471:Cell Transformation, Neoplastic / Q000473:pathology; D016001:Confidence Intervals; D004938:Esophageal Neoplasms / Q000473:pathology* / Q000601:surgery; D004945:Esophagoscopy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests