title: Delayed-phase dynamic CT enhancement as a prognostic factor for mass-forming intrahepatic cholangiocarcinoma.
abstract: OBJECTIVE
  To retrospectively determine whether the degree of contrast material enhancement at delayed-phase dynamic computed tomography (CT) for intrahepatic cholangiocarcinoma (ICC) is related to the patient's prognosis after surgery.
  
  
  METHODS
  Neither institutional review board approval nor informed consent was required for this retrospective evaluation. Thirty-two patients (22 men, 10 women; mean age, 60.8 years; range, 33-80 years) with mass-forming ICC underwent dynamic CT. Delayed CT images obtained 4-6 minutes after the injection of contrast material were evaluated by two radiologists. Patients were classified in consensus into one of two groups: Group 1 included those in whom more than two-thirds of the tumor showed enhancement on delayed-phase scans. Group 2 included those in whom less than two-thirds of the tumor showed enhancement on delayed-phase scans. The imaging findings were correlated with pathologic findings. Survival curves were drawn by using the Kaplan-Meier method, and the differences between the groups were compared with the log-rank test. Multivariate analysis was performed to clarify prognostic factors.
  
  
  RESULTS
  There were 13 patients in group 1 and 19 in group 2. The degree of enhancement on the delayed-phase images showed statistically significant correlation with the amount of fibrous stroma (P < .001) and the frequency of perineural invasion (P < .01). The survival rate in group 1 was significantly lower than that in group 2 (P = .016). Multivariate analysis revealed that enhancement of more than two-thirds of the ICC was a significant and independent prognostic factor.
  
  
  CONCLUSIONS
  The degree of enhancement on delayed-phase CT scans is a useful indicator for prediction of the prognosis of patients with mass-forming ICC.
authors.affiliation: Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Fukuoka 812-8582, Japan. asayama@radiol.med.kyushu-u.ac.jp
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Asayama
authors.forename: Kengo
authors.initials: K
authors.lastname: Yoshimitsu
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Irie
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Tajima
authors.forename: Akihiro
authors.initials: A
authors.lastname: Nishie
authors.forename: Masakazu
authors.initials: M
authors.lastname: Hirakawa
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Nakayama
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kakihara
authors.forename: Akinobu
authors.initials: A
authors.lastname: Taketomi
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Aishima
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Honda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001650:Bile Duct Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D001653:Bile Ducts, Intrahepatic / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D018281:Cholangiocarcinoma / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D003287:Contrast Media; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D015996:Survival Rate; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media