Figure 5: A 51-year-old man with glioblastoma. MRI clearly showed a ringed enhancement in the left temporo-occipital lobe (a). Areas of different enhancement and uptake between MET (b) and FLT (c) are projected on the tumor, in order to perform histological sampling for further correlation during the resection (blue arrow, green arrow, red arrow). Sample from the blue arrow demonstrates glioblastoma with oligodendroglioma (d) within high ratio of MET-PET (4.31) and low ratio of FLT-PET (3.24). Sample from the green arrow demonstrates necrosis area (f) within low ratio of MET-PET (1.60) and high ratio of FLT-PET (5.72). Sample from the red arrow demonstrates glioblastoma with multiple nuclear and large cells (h) within high ratio of MET (3.27) and FLT-PET (5.28). Ki-67 index was 30% for the blue arrow (e), less than 10% for the green arrow (g), and 70% for the red arrow (i). Taken together, increased accumulation of both tracers (MET and FLT) appears to indicate high-grade malignancy.