This lesion was proven HCC on biopsy. The portal and hepatic veins as well as the IVC and SVC should be looked at when HCC is suspected, in particular looking for direct tumor extension or thrombus. Interestingly in this patient, there appears to be heterogenous attenuation of the IVC but this is artefactual and is due to mixing of contrast coming in from the renal veins into the IVC. One can also see mass effect as the tumor compresses the proximal SVC.