Abstract
Brain tumors are the most common solid tumors in the pediatric population and account for the largest portion of childhood cancer-related deaths. Treatment choices for pediatric brain tumors depend on tumor type, location, stage, age and clinical status and surgical resection of the lesion is the primary treatment choice. Contrast-enhanced magnetic resonance (MR) imaging is the primary imaging modality used for diagnosis and presurgical evaluation. While MR imaging offers high anatomical resolution, conventional techniques are insufficient to clearly delineate tumor margins and demonstrate infiltration of surrounding normal tissue. This highlights the importance of molecular imaging methods using radionuclide agents. The development of hybrid imaging modalities such as positron emission tomography/computed tomography (PET/CT) and PET/MR imaging has further advanced pediatric research and clinical practice. Flourodeoxyglucose (FDG), the most commonly used PET radiopharmaceutical for imaging pediatric brain tumors, provides important information for diagnosis, staging, prognostication, treatment planning, treatment response assessment and recurrence detection; but it has limitations due to its physiological uptake in cortical tissue. Therefore, amino acid-based radiopharmaceuticals (C-11 MET, F-18 FET, F-18 DOPA) have been developed in addition to FDG and are being used in the evaluation of brain tumors. Amino acid PET offers significant advantages due to its high uptake in brain tumors, including low-grade gliomas, and low uptake in normal tissue. This increases diagnostic accuracy in the evaluation and follow-up of brain tumors.
Keywords: PET/CT, PET/MRI, pediatric brain tumors, amino-acid PET
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