Fig. 2.

85 year old male diagnosed with hepatocellular carcinoma (HCC). At presentation, contrast enhanced T₁ MRI (A), a solitary hypervascular lesion in segment 5, 6 and 8 with a maximum diameter of 8.1 cm was seen. At tumor board, the patient was considered for first-line SIRT. The ¹⁶⁶Ho scout procedure consisted of a single injection of 233 MBq of ¹⁶⁶Ho microspheres in the right hepatic artery (B) and subsequent SPECT/CT imaging showed no lung shunt, no extrahepatic deposition of activity elsewhere and visually good tumor targeting. The patient proceeded with ¹⁶⁶Ho treatment in the afternoon (on the same day), in which 4.3 GBq of ¹⁶⁶Ho microspheres were administered in the right hepatic artery (B). 3 months after treatment, follow-up contrast enhanced T₁ MRI (C), showed a good response reducing its size from 8.1 cm to 5.8 cm and complete response according to mRECIST. Post-treatment SPECT/CT (D) 3 days after treatment confirmed the planned high accumulation of particles in the lesion, without extrahepatic deposition of activity (and no lung shunt). At this moment, more than 3 years after treatment, the patient has no signs of recurrent disease on imaging