title: Preoperative Identification of a Prognostic Factor for Pancreatic Neuroendocrine Tumors Using Multiphase Contrast-Enhanced Computed Tomography.
abstract: OBJECTIVE
  To find predictive factors among computed tomography (CT) findings to identify pancreatic neuroendocrine tumors G2 of World Health Organization classification.
  
  
  METHODS
  Thirty-seven patients with pancreatic neuroendocrine tumors underwent multiphase contrast enhanced CT (unenhanced, arterial, pancreatic, portal and equilibrium phase), and attenuation values and imaging findings were examined. A receiver operating characteristic curve analysis was performed, and association between imaging findings and World Health Organization classification was evaluated.
  
  
  RESULTS
  Mean CT attenuation value of NET G1 was significantly higher than that of NET G2 throughout the arterial, pancreatic, and portal phases. Receiver operating characteristic analysis according to tumor size revealed sensitivity: 83.3%, specificity: 92.0% and area under the curve (AUC): 0.853, whereas that of corrected true enhancement values in the pancreatic phase revealed sensitivity: 91.7%, specificity: 84.0% and AUC: 0.897, which showed the highest AUC. Specific CT findings, such as irregular tumor contour, vessel involvement, and cystic degeneration/necrosis, were significantly associated with NET G2, but not to the extent of CT attenuation value and tumor size.
  
  
  CONCLUSIONS
  The CT enhancement in the pancreatic phase, and irregularity, vessel involvement, and cystic degeneration/necrosis were significant predictors of NET G2. These parameters might help in differentiating between NET G1 and G2, providing a basis for appropriate treatment.
authors.affiliation: From the *Department of Gastroenterological Surgery (Surgery II); †Department of Radiology, Nagoya University Graduate School of Medicine; ‡Department of Surgery, Nagoya Central Hospital, Nagoya, Japan.
authors.forename: Suguru
authors.initials: S
authors.lastname: Yamada
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Fujii
authors.forename: Kojiro
authors.initials: K
authors.lastname: Suzuki
authors.forename: Yoshikuni
authors.initials: Y
authors.lastname: Inokawa
authors.forename: Mitsuro
authors.initials: M
authors.lastname: Kanda
authors.forename: Goro
authors.initials: G
authors.lastname: Nakayama
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Sugimoto
authors.forename: Masahiko
authors.initials: M
authors.lastname: Koike
authors.forename: Shuji
authors.initials: S
authors.lastname: Nomoto
authors.forename: Michitaka
authors.initials: M
authors.lastname: Fujiwara
authors.forename: Akimasa
authors.initials: A
authors.lastname: Nakao
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kodera
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000145:classification / Q000175:diagnosis* / Q000601:surgery; D010179:Pancreas / Q000000981:diagnostic imaging* / Q000601:surgery; D010190:Pancreatic Neoplasms / Q000145:classification / Q000175:diagnosis* / Q000601:surgery; D057234:Preoperative Period; D011379:Prognosis; D012372:ROC Curve; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult
chemical_list: D003287:Contrast Media