title: Differential diagnosis of groove pancreatic carcinomas vs. groove pancreatitis: usefulness of the portal venous phase.
abstract: OBJECTIVE
  To clarify if the portal venous phase is helpful for the differential diagnosis of groove pancreatic carcinomas and groove pancreatitis.
  
  
  METHODS
  MDCT and MRI of groove pancreatic carcinomas (n=7) and groove pancreatitis (n=15) were retrospectively reviewed by two radiologists independently. The signal intensity on T2-weighted images was subjectively assessed. The presence or absence of common bile duct (CBD) and main pancreatic duct (MPD) strictures, calcifications, and cystic lesions was evaluated. Additionally, the appearance of groove pancreatic carcinoma and that of groove pancreatitis in the portal venous phase on dynamic MDCT and MRI were compared.
  
  
  RESULTS
  There were no significant differences in the signal intensity on T2-weighted images and in the presence or absence of CBD and MPD strictures, calcifications, and cystic lesions between groove pancreatic carcinomas and groove pancreatitis. However, patchy focal enhancement in the portal venous phase was more commonly observed in groove pancreatitis than groove pancreatic carcinoma (Reviewers 1 and 2: 14/15 [93.3%] vs. 1/7 [14.3%], P<0.0001). In addition, peripheral enhancement was only seen in groove pancreatic carcinomas (Reviewer 1: 4/7 [57.1%] vs. 0/15 [0%], P<0.005, and Reviewer 2: 3/7 [42.9%] vs. 0/15 [0%], P<0.05).
  
  
  CONCLUSIONS
  The portal venous phase may be helpful for the differential diagnosis of groove pancreatic carcinomas and groove pancreatitis.
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan. Ishigamikousei@aol.com
authors.forename: Kousei
authors.initials: K
authors.lastname: Ishigami
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Tajima
authors.forename: Akihiro
authors.initials: A
authors.lastname: Nishie
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kakihara
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Fujita
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Asayama
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ushijima
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Irie
authors.forename: Masafumi
authors.initials: M
authors.lastname: Nakamura
authors.forename: Shunichi
authors.initials: S
authors.lastname: Takahata
authors.forename: Tetsuhide
authors.initials: T
authors.lastname: Ito
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Honda
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000175:diagnosis*; D010195:Pancreatitis / Q000175:diagnosis*; D011169:Portal Vein / Q000000981:diagnostic imaging* / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*