title: EUS and K-ras analysis of pure pancreatic juice collected via a duodenoscope after secretin stimulation for diagnosis of pancreatic mass lesion: a prospective study.
abstract: BACKGROUND
  The early diagnosis of pancreatic cancer remains problematic. This prospective study assessed the utility of a combination of endoscopic ultrasound (EUS) and genetic analysis of pure pancreatic juice in the diagnosis of pancreatic mass lesions.
  
  
  METHODS
  One hundred seventy-six patients with suspected pancreatic disease were enrolled and underwent ultrasonography (US), computed tomography (CT), endoscopic retrograde choleangiopancreatography (ERCP), and EUS. Pure pancreatic juice was collected endoscopically after secretin stimulation. K-ras point mutations at codon 12 in the juice were assayed by polymerase chain reaction-restriction fragment length polymorphism.
  
  
  RESULTS
  Thirty-six (20%) patients were found to have solid pancreatic masses including 19 with cancer (7 patients, </= 2 cm) and 17 patients with an inflammatory mass (13 patients, </= 2 cm). US and CT were both less sensitive, particularly in patients with small masses. In 13 patients, small masses (4 cancer and 9 inflammatory masses) were not delineated until EUS. The combination of EUS and K-ras analysis had a high sensitivity (100%; p < 0.05 vs. US) and its accuracy reached 94% (p < 0.01 vs. US).
  
  
  CONCLUSIONS
  EUS and K-ras determination in pure pancreatic juice collected via a duodenoscope may be useful for the diagnosis of pancreatic mass lesions.
authors.affiliation: Department of Internal Medicine and Medical Oncology, Cancer Research Institute, Kanazawa University, Kanazawa, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Okai
authors.forename: H
authors.initials: H
authors.lastname: Watanabe
authors.forename: Y
authors.initials: Y
authors.lastname: Yamaguchi
authors.forename: I
authors.initials: I
authors.lastname: Mouri
authors.forename: Y
authors.initials: Y
authors.lastname: Motoo
authors.forename: N
authors.initials: N
authors.lastname: Sawabu
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002760:Cholangiopancreatography, Endoscopic Retrograde; D003937:Diagnosis, Differential; D020698:Duodenoscopes; D019160:Endosonography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010179:Pancreas / Q000473:pathology; D010189:Pancreatic Juice / Q000737:chemistry*; D010190:Pancreatic Neoplasms / Q000175:diagnosis* / Q000473:pathology; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D011446:Prospective Studies; D016283:Proto-Oncogene Proteins p21(ras) / Q000032:analysis*; D012633:Secretin; D014057:Tomography, X-Ray Computed
chemical_list: D012633:Secretin; C501009:HRAS protein, human; D016283:Proto-Oncogene Proteins p21(ras)