title: Differential diagnosis of pancreatic cancer and focal pancreatitis by using EUS-guided FNA.
abstract: BACKGROUND
  Despite advances in diagnostic imaging techniques, the differentiation between pancreatic cancer and focal pancreatitis remains difficult. This study evaluated the effectiveness of EUS-guided FNA in the differential diagnosis between pancreatic cancer and focal pancreatitis, with particular reference to detection of the K-ras point mutation.
  
  
  METHODS
  The study included 62 consecutive patients with pancreatic ductal cancer and 15 patients with focal pancreatitis demonstrated as a pancreatic mass lesion by EUS.
  
  
  RESULTS
  Sensitivity, specificity, overall accuracy, positive predictive value, and negative predictive value of cytopathologic diagnosis were 82%, 100%, 86%, 100%, and 58%, respectively. Sensitivity, specificity, overall accuracy, positive predictive value, and negative predictive value of histopathologic diagnosis were 44%, 100%, 55%, 100%, and 32%, respectively. The K-ras point mutation was found in 74% of pancreatic cancers and 0% of focal pancreatitis lesions. No complication of EUS-guided FNA was observed.
  
  
  CONCLUSIONS
  EUS-guided FNA is useful for the differential diagnosis of pancreatic mass lesions caused by pancreatic cancer and focal pancreatitis. Analysis for the K-ras point mutation in specimens obtained by EUS-guided FNA may enhance diagnostic accuracy in indeterminate cases.
authors.affiliation: Department of Gastroenterology, Aichi Cancer Center Hospital, Nagoya, Japan.
authors.forename: Kuniyuki
authors.initials: K
authors.lastname: Takahashi
authors.forename: Kenji
authors.initials: K
authors.lastname: Yamao
authors.forename: Kenji
authors.initials: K
authors.lastname: Okubo
authors.forename: Akira
authors.initials: A
authors.lastname: Sawaki
authors.forename: Nobumasa
authors.initials: N
authors.lastname: Mizuno
authors.forename: Reiko
authors.initials: R
authors.lastname: Ashida
authors.forename: Takashi
authors.initials: T
authors.lastname: Koshikawa
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ueyama
authors.forename: Kunio
authors.initials: K
authors.lastname: Kasugai
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hase
authors.forename: Shinichi
authors.initials: S
authors.lastname: Kakumu
mesh_terms: D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle; D003937:Diagnosis, Differential; D019160:Endosonography; D005260:Female; D011905:Genes, ras / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000235:genetics / Q000473:pathology*; D010195:Pancreatitis / Q000000981:diagnostic imaging* / Q000235:genetics / Q000473:pathology*; D017354:Point Mutation / Q000235:genetics; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies