title: Clinical significance of cathepsin E in pancreatic juice in the diagnosis of pancreatic ductal adenocarcinoma.
abstract: BACKGROUND
  It has been reported that cathepsin E (CTSE) is a non-secretory and intracellular aspartic proteinase found in the superficial epithelial cells of the stomach and that it is also expressed in pancreatic ductal adenocarcinoma. We evaluated the diagnostic value of CTSE in the pancreatic juice in the diagnosis of pancreatic ductal adenocarcinoma compared with that of CA19-9, carcinoembryonic antigen (CEA) and K-ras mutations.
  
  
  METHODS
  One hundred and one patients (25 with pancreatic ductal adenocarcinoma and 76 with chronic pancreatitis) were examined for the diagnostic significance of CTSE in the pancreatic juice in the diagnosis of pancreatic ductal adenocarcinoma. Forty of 101 patients (15 with pancreatic ductal adenocarcinoma and 25 with chronic pancreatitis) were examined to compare the diagnostic value of various tumor markers in the pancreatic juice, namely CA19-9, CEA, K-ras mutations and CTSE.
  
  
  RESULTS
  The detection frequency of CTSE was significantly higher in patients with pancreatic ductal adenocarcinoma (64.0%) than in patients with chronic pancreatitis (7.9%; chi2 = 34.76; P < 0.0001). The sensitivity, specificity and diagnostic accuracy of CTSE in the pancreatic juice for pancreatic ductal adenocarcinoma was 66.7, 92.0 and 82.5%, respectively. These values were more efficient in comparison with those of CA19-9, CEA and K-ras mutations. The main cause of the detection failure of CTSE in pancreatic ductal adenocarcinoma was obstruction of the main pancreatic duct. Sensitivity was 85.7% in patients without obstruction of the main pancreatic duct.
  
  
  CONCLUSIONS
  Cathepsin E in the pancreatic juice is a novel marker for a definitive diagnosis of pancreatic ductal adenocarcinoma.
authors: Department of Gastroenterology, Kyoto Second Red Cross Hospital, Japan.
authors: K
authors: K
authors: Uno
authors: T
authors: T
authors: Azuma
authors: M
authors: M
authors: Nakajima
authors: K
authors: K
authors: Yasuda
authors: T
authors: T
authors: Hayakumo
authors: H
authors: H
authors: Mukai
authors: T
authors: T
authors: Sakai
authors: K
authors: K
authors: Kawai
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism*; D018395:CA-19-9 Antigen / Q000378:metabolism; D002272:Carcinoembryonic Antigen / Q000378:metabolism; D021441:Carcinoma, Pancreatic Ductal / Q000175:diagnosis* / Q000378:metabolism*; D020059:Cathepsin E / Q000378:metabolism*; D002908:Chronic Disease; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D011905:Genes, ras; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009367:Neoplasm Staging; D010189:Pancreatic Juice / Q000378:metabolism*; D010190:Pancreatic Neoplasms / Q000175:diagnosis* / Q000378:metabolism*; D010195:Pancreatitis / Q000378:metabolism; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; D018395:CA-19-9 Antigen; D002272:Carcinoembryonic Antigen; D020059:Cathepsin E