To evaluate the characteristics of combined hepatocellular and
cholangiocarcinoma of the liver by imaging techniques, six patients (five male and one female), aged 46-60 years, with proved combined
tumors were selected for this study from the review of 500 resected specimens of liver
tumors. Images obtained from sonography, computed tomography (CT), angiography, and CT after
intraarterial injection of
iodized oil (
iodized-oil CT) were retrospectively reviewed and correlated with the appearance of pathologic specimens. Sonographic findings were round or ovoid hypoechoic masses with central hyperechoic area (target appearance) in all patients. On CT scans,
tumors were relatively well-defined low-and/or iso-attenuation masses in all patients. Angiography showed hypovascular masses in five patients. In one patient, the
tumor appeared as a hypovascular mass with a central hypervascular area. On
iodized-oil CT scans, all patients showed partial retention of
iodized oil in
tumors. Echogenicity in
tumors at sonography or attenuation in
tumors at CT could not be correlated with histologic difference in
tumors at pathologic specimens. However, the hypervascular area at angiography and the compact retention areas of
iodized oil at
iodized-oil CT corresponded to portions of
hepatocellular carcinoma within the combined
tumor. On the basis of our results, imaging features, including target appearance at sonography, hypovascular mass with central hypervascular portions at angiography, and partial retention of
iodized oil in
tumors at
iodized-oil CT, might be helpful in making accurate diagnosis of these rare
tumors.