Infiltrative hepatocellular carcinoma - tumor extension to the IVC and right atrium
Presentation
Right upper quadrant pain.
Patient Data
Abdomen
Established liver cirrhosis. The right lobe shows ill-defined heterogeneous mass lesion, initially hypodense with heterogeneous arterial enhancement and washout in the portal venous and delayed phases.
Portal vein thrombus at its division extending to both main portal branches partially filling their lumen.
Tumor thrombus is noted filling the right hepatic vein extending to the IVC till the right atrium (right atrial thrombus). It shows enhancement at the arterial phase with washout in portal venous and delayed phases.
Multiple porta hepatis lymph nodes, one of them showed calcification. Hepatic parenchymal calcifications are also noted.
Recanalized umbilical vein.
Case Discussion
The diagnosis, in this case, is based on the imaging features and the clinical data only, however, it is hard to consider other differentials other than hepatocellular carcinoma (HCC). Macrovascular invasion is characteristic of HCC with the involvement of the portal vein more common than the hepatic veins. It is a sign of poor prognosis.
IVC and portal vein thrombus are considered tumor thrombus, as they are following the tumor pattern of enhancement and the extension from the tumor itself. The appearance of vessel expansion is also suggestive of tumor thrombus but less specific than arterial enhancement.
Streak and thread appearance of the tumor thrombus is characteristic in angiography and contrast-enhanced CT due to parallel opacification of small vessels and arterial-venous shunting.
Differentiating bland from tumor thrombus is necessary as they have different management and prognosis. Bland thrombus is common in patients with chronic liver disease.