Non-routine tracers for PET imaging of high-grade glioma

Thorough imaging is crucial for diagnosis and treatment of high-grade gliomas (HGG), lethal brain tumours with median survival ranging 1-5 years after diagnosis. Positron-emission tomography (PET) is acquiring importance in imaging of HGG since it has the formidable advantage of providing information on tumour metabolism that may be critical for correct diagnosis and treatment planning. Recently employed PET tracers designed for the non-routine investigation of specific aspects of HGG metabolism, including hypoxia, neoangiogenesis, expression of integrins and stem cell markers, are reviewed herein. A thorough choice from among these non-routine tracers may provide important metabolic information complementing those obtained with more common PET analyses, for the sake of diagnostic, prognostic, treatment planning or research purposes.