FIGURE 4. Multitracer PET and MRI of 50-y-old male patient with recurrent glioblastoma in left parieto-occipital lobe. T1-weighted MR image shows large subcortical edema within left hemisphere surrounding contrast-enhancing tumor mass. Tumor shows increased [11C]MET uptake (3.1-fold higher than corresponding contralateral temporal region), high glucose consumption (37.3 µmol/100 g/min), and deactivation of surrounding cortex (62.1% of corresponding contralateral region). After systemic administration of 77 MBq [124I]FIAU, dynamic emission sequence over 68 h shows high FIAU accumulation within tumor, scalp, and soft tissue within first hour after injection (p.i.). At later times (8–24 h after injection), substantial FIAU uptake was also observed in peritumoral edematous areas. Washout of FIAU from these regions was slow. Substantial uptake of FIAU in contralateral gray and white matter was not observed.
