FDG PET Imaging of Brain Tumors

Abstract

Brain tumor imaging with FDG PET or FDG PET CT is often difficult to interpret, due to several limiting factors, including high background FDG uptake in the brain parenchyma especially the cerebral/cerebellar cortices and basal ganglia, the heterogeneity of primary and metastatic brain tumors with widely variable FDG uptake, and the altered brain and tumor glucose metabolic activity due to posttreatment changes (Chen, J Nucl Med 48(9):1468–1481, 2007; Demetriades et al., Surgeon 12(3):148–157, 2014; Hustinx and Fosse, PET Clin 5(2):185–197, 2010). Nevertheless, as shown in this chapter, FDG PET could provide unique tumor metabolic features that may guide accurate biopsy of brain tumors with uneven metabolic activity, help differentiate tumor recurrence from post-radiation necrosis, and facilitate pre-surgical brain tumor grading and treatment planning (Chen, J Nucl Med 48(9):1468–1481, 2007). Due to the overall suboptimal detection sensitivity of FDG PET, correlation of suspicious FDG PET findings with diagnostic brain MRI and/or CT is always recommended. Presented in this chapter are highly selected cases showing the value and limitation of FDG PET imaging in the evaluation of primary and recurrent glioblastoma multiforme (GBM), primary and secondary central nerve system (CNS) lymphomas, ganglioglioma, leptomeningeal melanoma, and metastatic lung and breast cancers to the brain.