title: MR imaging findings of early bile duct cancer.
abstract: OBJECTIVE
  To retrospectively evaluate the MR imaging features of early bile duct cancer and to correlate them with the clinicopathologic findings.
  
  
  METHODS
  This retrospective study was approved by our institutional review board, and informed consent was waived. Seventeen patients with surgically proven early bile duct cancer who had undergone preoperative MR cholangiopancreatography with gadolinium-enhanced MR imaging, were included in this study. Two, experienced radiologists evaluated the MR images in consensus regarding the following findings: tumor number and morphology; signal intensity of the tumor; sharpness of the outer border of the bile duct wall; enhancement pattern of the tumor; and the presence of enlarged peribiliary lymph nodes. Another radiologist measured the SNR of the tumor and bile duct wall on gadolinium-enhanced MRI during the dynamic phases to evaluate the tumor enhancement degree.
  
  
  RESULTS
  In all patients, MR imaging demonstrated single or multiple intraluminal bile duct masses showing a sharply defined outer margin. The most common enhancement pattern of the biliary lesions showed heterogeneous amorphous enhancement or heterogeneous enhancement with central, dot-like structures or vascular structures (76.5%, 13/17 patients). The difference of SNR between bile duct and tumor was greatest in the equilibrium phase (P < 0.05).
  
  
  CONCLUSIONS
  MRCP combined with dynamic contrast-enhanced MRI can be useful for detecting early bile duct cancers. Common MR findings of early bile duct cancer include one or more inhomogeneously enhancing intraductal masses with clear outer margins and preservation of the bile duct wall.
authors.affiliation: Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Dong Ho
authors.initials: DH
authors.lastname: Lee
authors.forename: Jeong Min
authors.initials: JM
authors.lastname: Lee
authors.forename: Kyung Won
authors.initials: KW
authors.lastname: Kim
authors.forename: Hee Sun
authors.initials: HS
authors.lastname: Park
authors.forename: Se Hyung
authors.initials: SH
authors.lastname: Kim
authors.forename: Jae Young
authors.initials: JY
authors.lastname: Lee
authors.forename: Joon Koo
authors.initials: JK
authors.lastname: Han
authors.forename: Byung Ihn
authors.initials: BI
authors.lastname: Choi
mesh_terms: D000368:Aged; D001650:Bile Duct Neoplasms / Q000175:diagnosis* / Q000473:pathology; D049448:Cholangiopancreatography, Magnetic Resonance; D003287:Contrast Media; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008536:Meglumine / Q000031:analogs & derivatives; D008875:Middle Aged; D009942:Organometallic Compounds; D012189:Retrospective Studies
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C064572:gadobenic acid; D008536:Meglumine