Brain Tumor Imaging: primary tumors...FDG-PET in primary brain glioma FDG-PET in primary brain...
Transcript of Brain Tumor Imaging: primary tumors...FDG-PET in primary brain glioma FDG-PET in primary brain...
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Brain Tumor Imaging: primary tumors and differentiation of radiation necrosis
vs tumor recurrence
Arnold Kang
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Aims of this lecture
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Type of cell Neoplasm
Glial cells:
Astrocyte Astrocytoma
Oligodendrocyte Oligodendroglioma
Ependyma Ependymoma
Choroid plexus Choroid plexus tumors (papilloma, carcinoma)
Nerve sheath cells
Schwann cells Schwannoma
Fibroblasts/Schwann cells Neurofibroma
Mesenchymal cells
Meninges Meningioma
Blood vessels Hemangioblastoma
Bone Sarcoma
Lymphocytes, leukocytes Lymphoma, leukemia, myeloma, Langerhans cell histiocytosis
Germ cells Germinoma, Teratomatous types (embryonal carcinoma, yolk sac tumor, teratoma, choriocarcinoma)
Other neuroepithelial cells Craniopharyngioma, Rathke’s cleft cyst
Endoderm, mesoderm, ectoderm Epidermoid/dermoid, lipoma, harmatoma
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WHO Classification of Glial Tumors
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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Conventional Imaging - MRI
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Conventional Imaging - MRI
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Metabolic Imaging – PET and SPECT
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Metabolic Imaging – PET and SPECT
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Metabolic Imaging – PET and SPECT
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Metabolic Imaging – 18F-FDG PET
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Metabolic Imaging – 18F-FDG PET
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Metabolic Imaging – 18F-FDG PET
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Metabolic Imaging – 18F-FDG PET
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Metabolic Imaging – 18F-FDG PET
• Image interpretation
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Metabolic Imaging – 18F-FDG PET
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Metabolic Imaging – 18F-FDG PET
• Delayed imaging
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Metabolic Imaging –Amino Acids PET
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Metabolic Imaging –Amino Acids PET
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Differential Diagnosis with PET
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Treatment Planning with PET
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Treatment Planning with PET
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Treatment Response with PET
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Tumor recurrence versus radiation necrosis
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Why do tumors enhance?
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MR with contrast
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Features of radiation necrosis
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Other complicating factors
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MR
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Is this tumor recurrence or radiation necrosis?
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Radiation necrosis in a 67-year-old man with a history of squamous cell carcinoma of the
scalp and nodal neck metastases.
Shah R et al. Radiographics 2012;32:1343-1359
©2012 by Radiological Society of North America
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Role of PET
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Recurrence vs Radiation Necrosis
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Legend to previous PET figure
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Dual time point imaging
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FDG-PET in primary brain glioma
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FDG-PET in primary brain glioma
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Tumor Recurrence vs. Radiation Necrosis
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Other radiotracers
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Other radiotracers
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Other radiotracers
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18F-FLT/11C-MET images
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Legend for previous figure
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Legend continued
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Legend continued
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Other radiotracers
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Other radiotracers
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A – T2WI MRI demonstrates focal area of increased signal intensity in the deep white matter of the right frontal lobeB- Corresponding T1WI demonstrates low signal intensity in the same regionF- Thallium-201 SPECT demonstrates increased radiotracer uptake in theCorresponding region
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MR spectroscopy – tumor recurrence
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MRS – a brief overview
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MRS
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Summary
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