Type:
Educational Exhibit
Keywords:
Neoplasia, Cancer, Education, MR, CT, Oncology, Liver, Abdomen
Authors:
N. Long1, I. Nikolovski2, R. Do2; 1New York, NY/US, 2New York/US
DOI:
10.26044/ecr2019/C-3260
Background
Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC) are the most common primary hepatic neoplasms accounting for around 70% and 15% of cases respectively. Mixed hepatocellular-cholangiocarcinoma (CHC) is a rare subtype of primary liver carcinoma (2.4 - 14.2% of primary liver tumors) with both hepatocellular and biliary epithelial differentiation which shares imaging features of both hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC) with a poor prognosis closer to that of ICC than HCC.
CHC was first described in 1949 by Allen & Lisa,
however due to its rarity,
there is a lack of understanding regarding biological behavior,
clinicopathologic characteristics and patient prognoses.
The imaging appearances of CHC frequently overlap with true HCC which can result in misdiagnosis unless there is a high index of suspicion for mixed tumors when atypical imaging findings are present.
This is of vital importance in patients undergoing evaluation for liver transplant as CHC is associated with poor post-transplant outcomes with increased recurrence rates and reduced survival.
(3-year survival of 48% verus 78% for HCC).
As tissue biopsy is not generally performed prior to transplantation if imaging findings are concordant,
radiologists should be alert to imaging features that raise the possibility of CHC as opposed to true HCC,
thereby identifying patients who require preoperative tissue biopsy.
Optimal management of patient with CHC is also in debate,
with some studies advocating aggressive surgical resection combined with lymphadenectomy,
further underscoring the importance of accurate diagnoses to allow appropriate treatment stratification.
We review the imaging appearances of CHC tumors with emphasis on features which should raise suspicion for a diagnosis of mixed pathology rather than classical HCC.