[Phosphorus MR spectroscopy and 18F-FDG PET/CT in the study of energy metabolism of glial tumors].

Objective: To study energy metabolism in glial tumors using dynamic MR spectroscopy and F-FDG PET/CT.

Material And Methods: The study included 19 patients (9 women and 10 men) with newly diagnosed supratentorial glial tumors WHO Grade I-IV (diffuse astrocytoma - 4 cases, oligodendroglioma - 4 cases, anaplastic astrocytoma - 5 cases, glioblastoma - 6 cases). All patients underwent examination and surgical treatment at the Burdenko Neurosurgery Center. Dynamic MR spectroscopy and F-FDG PET/CT were applied in each patient.

Results: We found multiple correlations between the ratio of bioorganic phosphate peaks and parameters of glucose uptake by tumor tissue. These relationships were more significant in patients with high-grade tumors: positive significant correlation between SUVtumor and PME/PCr ratio (R=0.75, =0.01), T/Nmix and βATP/Pi ratio (R=0.76, =0.02), SUVpeaktumor and aATP/Pi ratio (R=0.77, =0.008). Moreover, there were negative correlations between SUVtumor and PCr/bATP ratio (R= -0.66, =0.05), T/Nmix and PDE/bATP ratio (R= -0.83, =0.006), SUVpeaktumor and PDE/aATP ratio (R= -0.76, =0.009).

Conclusion: High-grade gliomas were characterized by higher glucose consumption, ATP release (intensification of energy metabolism) and faster cell membrane synthesis. These processes indicate enhanced proliferation of tumor cells (intensification of plastic metabolism).