title: CDX2 protein expression compared to alcian blue staining in the evaluation of esophageal intestinal metaplasia.
abstract: OBJECTIVE
  To compare the sensitivity and specificity of CDX2 and alcian blue (AB) pH 2.5 staining in identifying esophageal intestinal metaplasia.
  
  
  METHODS
  One hundred and ninty-nine biopsies from 186 patients were retrospectively reviewed and categorized as Barrett's esophagus (BE) (n = 108); non-Barrett's esophagus (NBE) (n = 48); columnar blue cells (CB) and esophageal glands (EG) (n = 43). The biopsies were stained with AB and immunostained for CDX2 using a mouse monoclonal antibody from Biogenex (clone CDX2-88) and the Ventana Discovery X automated immunostainer. The positive and negative predictive value of each group was used to determine the predictive power of CDX2 and AB in diagnosing intestinal metaplasia.
  
  
  RESULTS
  All of the 108 BE biopsies (100%) were positive for AB and 102 of them (94.4%) were positive for CDX2. The six BE patients (5.6%) who failed to stain with CDX2 were found to have lost the focus of intestinal metaplasia upon deeper sectioning for immunostaining. Both AB and CDX2 were negative in 43 out of 48 (89.6%) NBE cases. Five NBE patients (10.4%) were falsely positive for AB due to the presence of EG and CB in these biopsies. These cases were all CDX2 negative. In addition, 5 AB negative NBE were found to be CDX2 positive. Based on these results the CDX2 immunostain had similar sensitivity but higher specificity (100% vs about 91%) than AB in detecting intestinal type metaplasia in these samples. Our data shows that CDX2 has a better PPV in detecting intestinal metaplasia as compared to AB (95.6% vs 71.5%, respectively).
  
  
  CONCLUSIONS
  CDX2 has a better positive predictive value than AB in detecting intestinal metaplasia. CDX2 may be useful when challenged by gastro-esophageal biopsies containing mimikers of BE.
authors.affiliation: Dennis R Johnson, Maisoun Abdelbaqui, Maryam Tahmasbi, Domenico Coppola, Department of Anatomic Pathology, Moffitt Cancer Center and Research Institute, Tampa, FL 33612, United States.
authors.forename: Dennis R
authors.initials: DR
authors.lastname: Johnson
authors.affiliation: Dennis R Johnson, Maisoun Abdelbaqui, Maryam Tahmasbi, Domenico Coppola, Department of Anatomic Pathology, Moffitt Cancer Center and Research Institute, Tampa, FL 33612, United States.
authors.forename: Maisoun
authors.initials: M
authors.lastname: Abdelbaqui
authors.affiliation: Dennis R Johnson, Maisoun Abdelbaqui, Maryam Tahmasbi, Domenico Coppola, Department of Anatomic Pathology, Moffitt Cancer Center and Research Institute, Tampa, FL 33612, United States.
authors.forename: Maryam
authors.initials: M
authors.lastname: Tahmasbi
authors.affiliation: Dennis R Johnson, Maisoun Abdelbaqui, Maryam Tahmasbi, Domenico Coppola, Department of Anatomic Pathology, Moffitt Cancer Center and Research Institute, Tampa, FL 33612, United States.
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Mayer
authors.affiliation: Dennis R Johnson, Maisoun Abdelbaqui, Maryam Tahmasbi, Domenico Coppola, Department of Anatomic Pathology, Moffitt Cancer Center and Research Institute, Tampa, FL 33612, United States.
authors.forename: Hung-Wei
authors.initials: HW
authors.lastname: Lee
authors.affiliation: Dennis R Johnson, Maisoun Abdelbaqui, Maryam Tahmasbi, Domenico Coppola, Department of Anatomic Pathology, Moffitt Cancer Center and Research Institute, Tampa, FL 33612, United States.
authors.forename: Mokenge P
authors.initials: MP
authors.lastname: Malafa
authors.affiliation: Dennis R Johnson, Maisoun Abdelbaqui, Maryam Tahmasbi, Domenico Coppola, Department of Anatomic Pathology, Moffitt Cancer Center and Research Institute, Tampa, FL 33612, United States.
authors.forename: Domenico
authors.initials: D
authors.lastname: Coppola
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000423:Alcian Blue; D001471:Barrett Esophagus / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D001706:Biopsy; D000071616:CDX2 Transcription Factor; D004396:Coloring Agents; D004947:Esophagus / Q000737:chemistry* / Q000473:pathology*; D005260:Female; D018398:Homeodomain Proteins / Q000032:analysis*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008679:Metaplasia; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013194:Staining and Labeling / Q000379:methods*
chemical_list: D000071616:CDX2 Transcription Factor; C491270:CDX2 protein, human; D004396:Coloring Agents; D018398:Homeodomain Proteins; D000423:Alcian Blue
keywords: Alcian blue pH 2.5; Barrett’s esophagus; CDX2; Columnar blue cell; Esophageal glands; Intestinal metaplasia