title: Barrett's, blood groups and progression to oesophageal cancer: is nitric oxide the link?
abstract: BACKGROUND
  Incidence of oesophageal adenocarcinoma (OAC) is increasing rapidly. OAC arises in columnar-lined oesophagus (CLO), a metaplastic change affecting some patients with gastro-oesophageal reflux disease (GORD). As yet there is no reliable method of identifying those at highest risk. Our earlier observation of an association between OAC and blood group O Rhesus negative, if confirmed, may help identify those at greatest risk.
  
  
  OBJECTIVE
  To assess the distribution of blood group and Rhesus D (RhD) factor in patients with GORD compared with the blood donating general population. GORD was categorized as nonerosive reflux (NER), erosive oesophagitis, CLO and OAC. The Rotherham Hospital database holds details of all GORD, CLO and OAC patients seen in the Gastroenterology Unit. Blood group information for patients with GORD was obtained from patients' records and the hospital's blood transfusion service. The blood group distribution in the general population was obtained from the National Blood Transfusion Service. The number of expected to observed patients in each blood group for each subtype was compared.
  
  
  RESULTS
  Two thousand six hundred and ten NER, 2813 erosive oesophagitis, 568 CLO and 73 OAC patients had a recorded blood group. For RhD positive patients observed proportions in each blood group were similar to expected. The most striking difference was the marked excess of OAC in blood group O, Rhesus negative (P=0.002).
  
  
  CONCLUSIONS
  CLO patients with blood group O, RhD negative carry a disproportionately higher risk of developing OAC. The mechanism is unknown but the finding has practical application in guiding risk stratification and intensity of surveillance.
authors.affiliation: UK National Barrett's Oesophagus Registry, University College London, Department of Surgery and Interventional Science, Royal Free Hospital, Rotherham, UK. c.caygill@ucl.ac.uk
authors.forename: Christine P J
authors.initials: CP
authors.lastname: Caygill
authors.forename: Christine
authors.initials: C
authors.lastname: Royston
authors.forename: André
authors.initials: A
authors.lastname: Charlett
authors.forename: Christine M
authors.initials: CM
authors.lastname: Wall
authors.forename: Piers A C
authors.initials: PA
authors.lastname: Gatenby
authors.forename: James R
authors.initials: JR
authors.lastname: Ramus
authors.forename: Anthony
authors.initials: A
authors.lastname: Watson
authors.forename: Marc
authors.initials: M
authors.lastname: Winslet
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Hourigan
authors.forename: Karna
authors.initials: K
authors.lastname: Dev Bardhan
mesh_terms: D000017:ABO Blood-Group System; D000230:Adenocarcinoma / Q000097:blood* / Q000209:etiology; D001471:Barrett Esophagus / Q000097:blood* / Q000209:etiology; D001789:Blood Group Antigens; D018450:Disease Progression; D004938:Esophageal Neoplasms / Q000097:blood* / Q000209:etiology; D005260:Female; D005764:Gastroesophageal Reflux / Q000097:blood / Q000150:complications; D006801:Humans; D008297:Male; D009569:Nitric Oxide / Q000502:physiology*; D011230:Precancerous Conditions / Q000097:blood* / Q000209:etiology; D012189:Retrospective Studies; D012204:Rh-Hr Blood-Group System
chemical_list: D000017:ABO Blood-Group System; D001789:Blood Group Antigens; D012204:Rh-Hr Blood-Group System; D009569:Nitric Oxide