Case 236: Hepatocellular Carcinoma (HCC)
67 year old man with chronic hepatitis C infection. Screening ultrasound revealed a lesion in the right hepatic lobe. The lesion demonstrated mild increase in size over one year.
CT: Right hepatic vein invasion, with hypovascular THAD
3 phase CT shows biopsy proven moderately differentiated hypervascular HCC in segment 8 with washout on equilibrium phase and invasion into the right hepatic vein. Compare similar dynamic contrast enhancement pattern of primary tumor and tumor thrombus. Equilibriium images demonstrated posteriorly oriented tumor finger invading the hepatic vein.
Note hypovascular transient hepatic attenuation difference (THAD) on portal venous phase, which is less common than hypervascular ones: Tumor thrombus obliterated the right hepatic vein, causing delayed sinuisoidal opacification of the hepatic vascular territory that drains into that vein due to local congestion.
HCC was subsequently treated with Y90 radioembolization. See appearance months after treatment on MR.