18F-FDG and 68Ga-FAPI-04 PET/CT Imaging in a Patient With Hepatocellular Carcinoma After 90Y-SIRT

The 18F-FDG and 68Ga-FAPI-04 PET/CT imaging findings were reported in a 52-year-old man with hepatocellular carcinoma (HCC) 3 weeks after undergoing yttrium-90 selective internal radiation therapy (90Y-SIRT). Both viable tumors and tumor thrombus of right portal vein showed mild-to-moderate 18F-FDG uptake, while peritumoral tissues showed high 68Ga-FAPI-04 uptake, the range of which approximately matched radiotracer distribution on 90Y SPECT/CT. Our findings indicate that 18F-FDG PET/CT is superior to 68Ga-FAPI-04 PET/CT for identifying viable HCC tumors during early 90Y-SIRT monitoring, whereas 68Ga-FAPI-04 PET/CT indirectly delineates the area of 90Y-SIRT.