title: Primary sclerosing cholangitis patients with serial polysomy fluorescence in situ hybridization results are at increased risk of cholangiocarcinoma.
abstract: OBJECTIVE
  A polysomy fluorescence in situ hybridization (FISH) result in a pancreatobiliary brushing from a patient with primary sclerosing cholangitis (PSC) is very worrisome for carcinoma. However, treatment is not recommended unless verified by corroborative evidence of malignancy because of less than perfect test specificity in this population. The aim of this study was to evaluate the clinical outcome of PSC patients with serial polysomy FISH results.
  
  
  METHODS
  Patients with PSC underwent endoscopic retrograde cholangiopancreatography with brushings when clinically indicated per standard practice. Brushings were evaluated by routine cytology and FISH. Retrospective review identified patients with a polysomy FISH result without definitive imaging or pathological evidence of malignancy at the time of the first polysomy, who underwent follow-up examinations including subsequent FISH testing (n=30). Patient records were reviewed to determine clinical outcome.
  
  
  RESULTS
  In all, 9 of 13 patients (69%) with a subsequent polysomy result (i.e., serial polysomy) were diagnosed with cholangiocarcinoma (CCA) compared with 3 of 17 patients (18%) with subsequent non-polysomy results (P=0.008). There was a significant difference in time to a diagnosis of CCA between PSC patients with serial polysomy compared with those with subsequent non-polysomy (P=0.01). In four patients with serial polysomy results, imaging/pathological evidence of CCA was not found until 1-2.7 years after the initial polysomy FISH result.
  
  
  CONCLUSIONS
  FISH may detect polysomic cells in pancreatobiliary brushings before other pathological or imaging techniques identify CCA. Patients with serial polysomy FISH results are at higher risk for having CCA than those with subsequent non-polysomy FISH results.
authors.affiliation: Department of Laboratory Medicine, Mayo Clinic College of Medicine, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA.
authors.forename: Emily G
authors.initials: EG
authors.lastname: Barr Fritcher
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Kipp
authors.forename: Jesse S
authors.initials: JS
authors.lastname: Voss
authors.forename: Amy C
authors.initials: AC
authors.lastname: Clayton
authors.forename: Keith D
authors.initials: KD
authors.lastname: Lindor
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Halling
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Gores
mesh_terms: D000328:Adult; D000368:Aged; D001650:Bile Duct Neoplasms / Q000175:diagnosis* / Q000473:pathology; D001653:Bile Ducts, Intrahepatic / Q000473:pathology*; D018281:Cholangiocarcinoma / Q000175:diagnosis* / Q000473:pathology; D002760:Cholangiopancreatography, Endoscopic Retrograde; D015209:Cholangitis, Sclerosing / Q000235:genetics* / Q000473:pathology; D058674:Chromosome Duplication; D055088:Early Detection of Cancer; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011230:Precancerous Conditions / Q000235:genetics* / Q000473:pathology; D012307:Risk Factors; D055815:Young Adult