title: DNA mutational differences in cytological specimens from pancreatic cancer and cholangiocarcinoma.
abstract: OBJECTIVE
  Preoperative distinction between pancreatic cancer (PC) and extrahepatic cholangiocarcinoma (CC) is desirable due to diverging management options, and to optimize enrollment into neoadjuvant trials.
  
  
  METHODS
  A single-center retrospective study of patients with PC or CC was undertaken. Four blinded pathologists reviewed all cases and reached a consensus diagnosis (PC or CC). Microdissection-based multiple microsatellite loss analysis and direct sequencing of K-ras oncogene was performed and compared for PC and CC.
  
  
  RESULTS
  Of 33 cases studied (17 males; 16 PC, 17 CC; 10 with primary sclerosing cholangitis), a K-ras mutation was present in 14/16 (87.5%) PC and 1/17 (5.9%) CC cases (p < 0.001), sensitivity and specificity were 87.5 and 94%, respectively. The mean fractional mutational rate was higher in PC (0.51; 95% CI 0.45-0.58) compared to CC (0.34; 95% CI 0.28-0.39, p < 0.001).
  
  
  CONCLUSIONS
  The presence of a K-ras mutation in cytology specimens distinguishes PC from CC in this study. and IAP.
authors: Department of Medicine, The University of Pittsburgh Medical Center, Pittsburgh, Pa, USA.
authors: Kenneth E
authors: KE
authors: Fasanella
authors: Alyssa
authors: A
authors: Krasinskas
authors: Karen E
authors: KE
authors: Schoedel
authors: Eizaburo
authors: E
authors: Sasatomi
authors: Adam
authors: A
authors: Slivka
authors: David C
authors: DC
authors: Whitcomb
authors: Michael
authors: M
authors: Sanders
authors: Laurentia
authors: L
authors: Nodit
authors: Stephen
authors: S
authors: Raab
authors: Kevin M
authors: KM
authors: McGrath
authors: N Paul
authors: NP
authors: Ohori
authors: Asif
authors: A
authors: Khalid
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001650:Bile Duct Neoplasms / Q000175:diagnosis / Q000235:genetics*; D001653:Bile Ducts, Intrahepatic / Q000473:pathology*; D021441:Carcinoma, Pancreatic Ductal / Q000175:diagnosis / Q000235:genetics*; D018281:Cholangiocarcinoma / Q000175:diagnosis / Q000235:genetics*; D015209:Cholangitis, Sclerosing / Q000235:genetics / Q000473:pathology; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D011905:Genes, ras / Q000235:genetics; D006801:Humans; D008297:Male; D042282:Microdissection; D053842:Microsatellite Instability; D008875:Middle Aged; D009154:Mutation; D010190:Pancreatic Neoplasms / Q000175:diagnosis / Q000235:genetics*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D004273:DNA, Neoplasm