title: Advanced cytologic techniques for the detection of malignant pancreatobiliary strictures.
abstract: OBJECTIVE
  Two advanced cytologic techniques for detecting aneuploidy-digital image analysis (DIA) and fluorescence in situ hybridization (FISH)-have recently been developed to help identify malignant pancreatobiliary strictures. The aim of this study was to assess the clinical utility of cytology, DIA, and FISH for the identification of malignant pancreatobiliary strictures.
  
  
  METHODS
  Brush cytologic specimens from 233 consecutive patients undergoing endoscopic retrograde cholangiopancreatography for pancreatobiliary strictures were examined by all 3 (cytology, DIA, and FISH) techniques. Strictures were stratified as proximal (n = 33) or distal (n = 114) based on whether they occurred above or below the cystic duct, respectively. Strictures in patients with primary sclerosing cholangitis (n = 86) were analyzed separately.
  
  
  RESULTS
  Despite the stratification, the performances of the tests were similar. Conventional cytology has a low sensitivity (4%-20%) but 100% specificity. Because of the high specificity for cytology, we assessed the performance of the other tests when conventional cytology was negative. In this clinical context, FISH had an increased sensitivity (35%-60%) when assessing for chromosomal gains (polysomy) while preserving the specificity of cytology. The sensitivity and specificity of DIA was intermediate as compared with routine cytology and FISH but was additive to FISH values demonstrating only trisomy of chromosome 7 or chromosome 3.
  
  
  CONCLUSIONS
  These findings suggest that FISH and DIA increase the sensitivity for the diagnosis of malignant pancreatobiliary tract strictures over that obtained by conventional cytology while maintaining an acceptable specificity.
authors.affiliation: Division of Gastroenterology and Hepatology, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: Laura E
authors.initials: LE
authors.lastname: Moreno Luna
authors.forename: Benjamin
authors.initials: B
authors.lastname: Kipp
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Halling
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Sebo
authors.forename: Walter K
authors.initials: WK
authors.lastname: Kremers
authors.forename: Lewis R
authors.initials: LR
authors.lastname: Roberts
authors.forename: Emily G
authors.initials: EG
authors.lastname: Barr Fritcher
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Levy
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Gores
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000782:Aneuploidy; D002648:Child; D002760:Cholangiopancreatography, Endoscopic Retrograde; D001651:Cholestasis, Extrahepatic / Q000209:etiology / Q000473:pathology*; D003251:Constriction, Pathologic; D004273:DNA, Neoplasm / Q000032:analysis; D003663:Decision Trees; D003936:Diagnosis, Computer-Assisted; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000295:instrumentation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000150:complications / Q000473:pathology*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity
chemical_list: D004273:DNA, Neoplasm