Metabolic response of glioblastoma to adoptive immunotherapy: detection by phosphorus MR spectroscopy

In a patient with cerebral glioblastoma, metabolic disturbances were detected within the tumor and in the surrounding brain. Within the volume occupied by the tumor, phosphocreatine (PCr)/adenosine triphosphate was reduced and inorganic phosphate/PCr elevated, indicative of tissue necrosis. Loss of total 31P signal was consistent with reduced metabolite content within the area of tumor defined by CT and magnetic resonance (MR). These studies were accomplished with 31P MR spectroscopy at 2 T, using a volume head coil and the technique of two-dimensional phase-encoding to map regional metabolism across the entire cerebral cortex in voxels of 30 cm3. Using the same method, only minor variations in 31P metabolism were noted in six normal controls. Treatment with locally placed Interleukin-2 activated lymphocytes resulted in changes in both MR and 31P MR spectroscopy in the region of the tumor.