Patient 20. (a) Large hypovascular HCC in the right lobe, seen on contrast-enhanced CT Abdomen. (b) Catheter-directed CT angiogram of the right hepatic artery demonstrates tumor hypovascularity and delineates the target arterial territory. (c)90Y PET/CT depicts, in high resolution, a rim-like activity in the tumor periphery with a large area of relative central photopenia, typical of hypovascular tumors. (d)90Y bremsstrahlung SPECT/CT poorly demonstrates the peripheral activity due to its low image resolution and under-represents the extent of central photopenia.