title: Acceptability and accuracy of a non-endoscopic screening test for Barrett's oesophagus in primary care: cohort study.
abstract: OBJECTIVE
  To determine the accuracy and acceptability to patients of non-endoscopic screening for Barrett's oesophagus, using an ingestible oesophageal sampling device (Cytosponge) coupled with immunocytochemisty for trefoil factor 3.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  12 UK general practices, with gastroscopies carried out in one hospital endoscopy unit.
  
  
  METHODS
  504 of 2696 eligible patients (18.7%) aged 50 to 70 years with a previous prescription for an acid suppressant (H(2) receptor antagonist or proton pump inhibitor) for more than three months in the past five years.
  
  
  METHODS
  Sensitivity and specificity estimates for detecting Barrett's oesophagus compared with gastroscopy as the ideal method, and patient anxiety (short form Spielberger state trait anxiety inventory, impact of events scale) and acceptability (visual analogue scale) of the test.
  
  
  RESULTS
  501 of 504 (99%) participants (median age 62, male to female ratio 1:1.2) successfully swallowed the Cytosponge. No serious adverse events occurred. In total, 3.0% (15/501) had an endoscopic diagnosis of Barrett's oesophagus (≥1 cm circumferential length, median circumferential and maximal length of 2 cm and 5 cm, respectively) with intestinal metaplasia. Compared with gastroscopy the sensitivity and specificity of the test was 73.3% (95% confidence interval 44.9% to 92.2%) and 93.8% (91.3% to 95.8%) for 1 cm or more circumferential length and 90.0% (55.5% to 99.7%) and 93.5% (90.9% to 95.5%) for clinically relevant segments of 2 cm or more. Most participants (355/496, 82%, 95% confidence interval 78.9% to 85.1%) reported low levels of anxiety before the test, and scores remained within normal limits at follow-up. Less than 4.5% (2.8% to 6.1%) of participants reported psychological distress a week after the procedure.
  
  
  CONCLUSIONS
  The performance of the Cytosponge test was promising and the procedure was well tolerated. These data bring screening for Barrett's oesophagus into the realm of possibility. Further evaluation is recommended.
authors.affiliation: MRC Cancer Cell Unit, Hutchison-MRC Research Centre, Cambridge CB2 2XZ.
authors.forename: Sudarshan R
authors.initials: SR
authors.lastname: Kadri
authors.forename: Pierre
authors.initials: P
authors.lastname: Lao-Sirieix
authors.forename: Maria
authors.initials: M
authors.lastname: O'Donovan
authors.forename: Irene
authors.initials: I
authors.lastname: Debiram
authors.forename: Madhumita
authors.initials: M
authors.lastname: Das
authors.forename: Jane M
authors.initials: JM
authors.lastname: Blazeby
authors.forename: Jon
authors.initials: J
authors.lastname: Emery
authors.forename: Alex
authors.initials: A
authors.lastname: Boussioutas
authors.forename: Helen
authors.initials: H
authors.lastname: Morris
authors.forename: Fiona M
authors.initials: FM
authors.lastname: Walter
authors.forename: Paul
authors.initials: P
authors.lastname: Pharoah
authors.forename: Richard H
authors.initials: RH
authors.lastname: Hardwick
authors.forename: Rebecca C
authors.initials: RC
authors.lastname: Fitzgerald
mesh_terms: D000368:Aged; D001007:Anxiety / Q000209:etiology; D001471:Barrett Esophagus / Q000175:diagnosis* / Q000473:pathology; D004867:Equipment Design; D005260:Female; D005773:Gastroscopy / Q000379:methods / Q000523:psychology; D005781:Gelatin Sponge, Absorbable; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008403:Mass Screening / Q000295:instrumentation / Q000523:psychology; D008875:Middle Aged; D017060:Patient Satisfaction; D010455:Peptides / Q000378:metabolism*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D000071165:Trefoil Factor-3
chemical_list: D010455:Peptides; C082495:TFF3 protein, human; D000071165:Trefoil Factor-3