title: Small solid tumors (< or = 2 cm) of the pancreas: relative accuracy and differentiation of CT and MR imaging.
abstract: OBJECTIVE
  To determine the relative accuracy of CT and MRI in characterization of solid pancreatic masses (< or = 2cm) and useful imaging appearance for differentiating small pancreatic duct adenocarcinoma (PDAC) from other small solid pancreatic neoplasms.
  
  
  METHODS
  CT and MRI scans of 46 patients with evidence of small pancreatic solid tumor were retrospectively evaluated, who underwent CT (n=30), MRI (n=4), or both (n=12). Two gastrointestinal radiologists independently recorded specific morphological features of tumors and the most likely diagnosis.
  
  
  RESULTS
  With respect to specific histopathological characterization, CT and MRI were equally accurate. The mean number of correct diagnoses made by the two reviewers was 37.5 (88.4%) of 42 cases for CT compared to 12 (75%) of 16 cases for MRI (p=0.388). Location in the pancreatic head (p=0.000), presence of dilatation of MPD (p=0.000), presence of dilatation of CBD (p=0.001) and enhancement pattern (p=0.000) were statistically significant for differentiating PDAC from the other small solid pancreatic tumors, while pancreatic atrophy (p=0.069) was statistically inadequate for differentiation, although it gave a 96.4% specificity for the diagnosis of PDAC.
  
  
  CONCLUSIONS
  CT and MRI are similarly accurate in the characterization of small solid pancreatic tumors. Small PDAC has characteristic CT and MRI findings that differentiate it from other small solid tumors.
authors.affiliation: Department of Radiology, Zhongshan Hospital, Fudan University and Shanghai Medical Imaging Institute, Shanghai, China.
authors.forename: Sheng-Xiang
authors.initials: SX
authors.lastname: Rao
authors.forename: Meng-Su
authors.initials: MS
authors.lastname: Zeng
authors.forename: Wei-Zhong
authors.initials: WZ
authors.lastname: Cheng
authors.forename: Xiu-Zhong
authors.initials: XZ
authors.lastname: Yao
authors.forename: Da-Yong
authors.initials: DY
authors.lastname: Jin
authors.forename: Yuan
authors.initials: Y
authors.lastname: Ji
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D021441:Carcinoma, Pancreatic Ductal / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*