title: Expression of Markers of Hepatocellular Differentiation in Pancreatic Acinar Cell Neoplasms:  A Potential Diagnostic Pitfall.
abstract: OBJECTIVE
  Pancreatic acinar cell carcinoma (ACC) is a rare tumor that frequently metastasizes to the liver and may present a diagnostic challenge due to its morphologic similarity to hepatocellular carcinoma. We investigated α-fetoprotein (AFP), hepatocyte paraffin antigen 1 (HepPar 1), glypican 3, arginase 1, and albumin messenger RNA (mRNA) in situ hybridization (ISH) in pancreatic neoplasms with ACC differentiation to assess their diagnostic value.
  
  
  METHODS
  AFP, HepPar 1, glypican 3, and arginase 1 immunohistochemical staining was performed on 28 ACCs using a tissue microarray. Albumin mRNA ISH was performed on full-faced sections.
  
  
  RESULTS
  Fifteen tumors were positive for at least one marker. Glypican 3 was positive in seven of 28, AFP in five 28, and albumin mRNA ISH in five of 20. None expressed arginase 1.
  
  
  CONCLUSIONS
  Hepatocellular differentiation markers, including albumin mRNA ISH, may be positive in ACC, but arginase 1 appears to be uniformly negative. Thus, its use may improve the accuracy in distinguishing these neoplasms from hepatocellular carcinoma. If ACC diagnosis is considered, acinar differentiation can be reliably demonstrated by trypsin/chymotrypsin.
authors.affiliation: From the Memorial Sloan Kettering Cancer Center, New York, NY.
authors.forename: Gokce
authors.initials: G
authors.lastname: Askan
authors.affiliation: Massachusetts General Hospital, Boston.
authors.forename: Vikram
authors.initials: V
authors.lastname: Deshpande
authors.affiliation: From the Memorial Sloan Kettering Cancer Center, New York, NY.
authors.forename: David S
authors.initials: DS
authors.lastname: Klimstra
authors.affiliation: Emory University, Atlanta, GA.
authors.forename: Volkan
authors.initials: V
authors.lastname: Adsay
authors.affiliation: From the Memorial Sloan Kettering Cancer Center, New York, NY.
authors.forename: Carlie
authors.initials: C
authors.lastname: Sigel
authors.affiliation: From the Memorial Sloan Kettering Cancer Center, New York, NY.
authors.forename: Jinru
authors.initials: J
authors.lastname: Shia
authors.affiliation: From the Memorial Sloan Kettering Cancer Center, New York, NY basturko@mskcc.org.
authors.forename: Olca
authors.initials: O
authors.lastname: Basturk
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D018267:Carcinoma, Acinar Cell / Q000175:diagnosis*; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis*; D002454:Cell Differentiation; D003937:Diagnosis, Differential; D006801:Humans; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000175:diagnosis*; D010190:Pancreatic Neoplasms / Q000175:diagnosis*; D046888:Tissue Array Analysis
chemical_list: D014408:Biomarkers, Tumor
keywords: Acinar cell carcinoma; Albumin ISH; Arginase 1; Glypican 3; Hepatocellular carcinoma; Pancreas