Computed tomography features of an intraductal polypoid mass: differentiation between hepatocellular carcinoma with bile duct tumor invasion and intraductal papillary cholangiocarcinoma.
OBJECTIVE
To determine the computed tomography (CT) features capable of differentiating hepatocellular carcinoma (HCC) with bile duct tumor invasion (BDTI) from intraductal cholangiocarcinoma (IDCC).


METHODS
Multiphasic CT images of 14 patients with HCC with BDTI and 18 patients with IDCC were retrospectively reviewed. Analysis of the CT findings included the size, location, and margin of the intraductal mass; enhancement pattern of intraductal lesions; degree of ductal dilatation; presence of downstream ductal dilatation and ductal wall thickening; presence of a parenchymal mass and its size; continuity of the parenchymal mass with the intraductal mass; and liver cirrhosis. Objective evaluation of the enhancement patterns of intraductal tumors was done by measuring the CT attenuation coefficients of the tumors and the uninvolved hepatic parenchyma in each phase. Among these findings, statistically significant variables were then determined using the Fisher's exact test or Mann-Whitney U test.


RESULTS
Significant variables that helped to differentiate HCC with BDTI from IDCC included the presence of a parenchymal mass, liver cirrhosis, and a hyperattenuating intraductal tumor on the hepatic arterial phase (HAP). On unenhanced images, the tumor-to-liver contrast of IDCC (16.7+/-8.1) was greater than that of HCC with BDTI (6.4+/-10.4), but on the HAP, that of HCC with BDTI (26.5+/-28.2) was greater than that of IDCC (5.9+/-18.7) (P<0.05). In addition, there was a significant difference in the enhancement ratio of the intraductal tumors on the portal venous phase between the 2 conditions (P=0.003).


CONCLUSIONS
Several objective and subjective multiphasic CT findings may help to differentiate HCC with BDTI from IDCC.
Jung
Ah Young
AY
Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul, Korea.
Lee
Jeong Min
JM
Choi
Seung Hong
SH
Kim
Se Hyung
SH
Lee
Jae Young
JY
Kim
Sun-Whe
SW
Han
Joon Koo
JK
Choi
Byung Ihn
BI
D000328:Adult; D000368:Aged; D001650:Bile Duct Neoplasms / Q000000981:diagnostic imaging*; D001653:Bile Ducts, Intrahepatic / Q000000981:diagnostic imaging*; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging*; D018281:Cholangiocarcinoma / Q000000981:diagnostic imaging*; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008113:Liver Neoplasms / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed / Q000379:methods*
D003287:Contrast Media