title: Pancreatic adenocarcinoma versus chronic pancreatitis: differentiation with triple-phase helical CT.
abstract: BACKGROUND
  Chronic pancreatitis and pancreatic adenocarcinoma often show similar clinical and imaging appearances. This study aims to differentiate chronic pancreatitis from pancreatic adenocarcinoma by defining enhancement patterns in both pathologic conditions during triple-phase helical CT.
  
  
  METHODS
  The study included 42 patients with chronic pancreatitis and 85 patients with pancreatic adenocarcinoma. CT images obtained according to protocol A (scan delays, 30, 60, and 150 s; 300 mg I/mL contrast material) or protocol B (scan delays, 40, 70, and 150 s; 370 mg I/mL contrast material) were retrospectively evaluated.
  
  
  RESULTS
  Mean contrast enhancement value of normal pancreas peaked in the first phase (early-washout pattern) while that of chronic pancreatitis peaked in the second phase (delayed-washout pattern), and that of pancreatic adenocarcinoma gradually rose (increasing pattern) in both protocols. Diagnostic indices for pancreatic adenocarcinoma were 82.4% and 94.1% for sensitivity, 83% and 83% for specificity, 82.7% and 90.4% for accuracy in protocols A and B, respectively, when differentiation between chronic pancreatitis and pancreatic adenocarcinoma was performed based on time-attenuation curve patterns.
  
  
  CONCLUSIONS
  Our results indicate that time attenuation curves obtained from triple-phase helical CT in protocol B provide useful information in differentiating chronic pancreatitis from pancreatic adenocarcinoma.
authors.affiliation: Department of Diagnostic and Interventional Radiology, Oita University Faculty of Medicine, Yufu-city, Oita, Japan.
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Yamada
authors.forename: Hiromu
authors.initials: H
authors.lastname: Mori
authors.forename: Shunro
authors.initials: S
authors.lastname: Matsumoto
authors.forename: Hiro
authors.initials: H
authors.lastname: Kiyosue
authors.forename: Yuko
authors.initials: Y
authors.lastname: Hori
authors.forename: Norio
authors.initials: N
authors.lastname: Hongo
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D002908:Chronic Disease; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007472:Iohexol; D007479:Iopamidol; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging*; D010195:Pancreatitis / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D036542:Tomography, Spiral Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol; D007479:Iopamidol