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Neuroimaging in Nuclear Medicine
Published in Michael Ljungberg, Handbook of Nuclear Medicine and Molecular Imaging for Physicists, 2022
Anne Larsson Strömvall, Susanna Jakobson Mo
Brain tumours are treated with surgery and in many cases chemotherapy and radiotherapy are indicated. Imaging of brain tumours primarily rely on MRI. However, there are several implications for functional neuroimaging in the diagnostic work-up and during the course of treatment of gliomas [2].
Advances in Nanotheranostics with Plasmonic and Magnetic Nanoparticles
Published in Carla Vitorino, Andreia Jorge, Alberto Pais, Nanoparticles for Brain Drug Delivery, 2021
Sérgio R. S. Veloso, Paula M. T. Ferreira, J. A. Martins, Paulo J. G. Coutinho, Elisabete M. S. Castanheira
Considering the difficulty of early stage detection and the proximity to anatomical structures responsible for essential functions, malignant glioma therapy is currently imposed as one of the greatest challenges [12, 13], which worsens owing to peritumoural oedema, not providing a precise discrimination of tumour margins [14], and the blood-brain barrier (BBB) hindering most of the chemotherapeutic drugs from reaching the tumour [15, 16]. From the different glioma varieties, glioblastoma multiforme (GBM) is the most aggressive malignancy of the central nervous system (CNS), with an incidence rate of about 3.19 per 100.000 people per annum and a median survival less than 2 years [17, 18], where only 5% survive longer than 5 years. This type of glioma is associated with an extensive infiltration, a strong vascular proliferation and a complex genetic expression, including additions in chromosomes 7 and 19, losses in chromosomes 10 and 13, gene amplifications and mutations, changes in mitotic and cellular activity, significant angiogenesis and necrosis [18, 19]. Hereby, brain tumour is a challenge for surgical, chemotherapeutic and radiotherapeutic conventional methods, which produce various side effects, such as resistance to therapy, devastating neurologic deterioration and the emergence of therapy-resistant populations [12].
Central Nervous System
Published in Pat Price, Karol Sikora, Treatment of Cancer, 2020
The underlying cause of the majority of CNS tumors is unknown. The only environmental factor that is clearly associated with an increased risk of developing a brain tumor is exposure to ionizing radiation, particularly at a young age. Radiation-induced tumors include astrocytomas of all grades, benign and malignant meningiomas, sarcomas, and nerve sheath tumors. A genetic contribution to etiology is also becoming better understood. In addition to a small number of rare syndromes associated with an increased risk of brain tumor (Table 1.2), genome wide association studies (GWAS) have defined at least 10 risk loci for glioblastoma (GBM) and non-GBM tumors.2 These do not increase the risk enough to merit screening approaches (relative risks 1.2–1.4) and are of variable penetrance; nevertheless, identifying them contributes important information in the understanding of gliomagenesis. The immune environment also contributes to tumor promotion, as evidenced by the fact that systemic immunosuppression due to a variety of causes (e.g., immunosuppression following transplant or human immunodeficiency virus [HIV] infection) predisposes to CNS tumors, including primary CNS lymphoma (PCNSL). Current evidence examining lifestyle or environmental exposure has not suggested a specific contribution to etiology.
Natural substances to potentiate canonical glioblastoma chemotherapy
Published in Journal of Chemotherapy, 2021
Antonietta Arcella, Massimo Sanchez
Inhibition of EGFR has recently been reported to lead to increased secretion of tumor necrosis factor (TNF) and activation of a survival pathway in GBM.102 One of the big problems with the treatment of brain tumors is that not all drugs overcome the blood-brain barrier, so there are few remedies available for brain tumor treatment. In this regard, phytocompounds reduce tumorigenesis, preventing metastasis and/or increasing chemotherapy and radiotherapy efficacy.103 Nanotechnology was used to increase the targeted diffusion of phytochemicals into the brain, which is known to be generally low, due to the presence of the blood brain barrier (BBB). In particular, nanocarriers have recently been created to deliver therapeutic useful loads within the tumor mass. Several polymer nanoparticles that diffuse into the brain (NP) have been used for the treatment of brain tumors. NPs loaded with drugs or natural compounds have shown improved intracranial drug delivery.104,105 In particular, the use of NPs loaded with phytocompounds could represent an effective strategy to block the growth of GBM and other brain tumors, combining the use of relatively non-toxic natural compounds with temozolomide and enhancing their drug delivery with nanotechnologies. NPs can be designed to increase their tropism and specificity toward BBB by conjugating their surface with specific receptors for BBB antigens, receptor ligand, for example lactoferrin can cross the BBB through receptor-mediated transcytosis.106
Recent advances in iron oxide nanoparticles for brain cancer theranostics: from in vitro to clinical applications
Published in Expert Opinion on Drug Delivery, 2021
Roghayeh Sheervalilou, Milad Shirvaliloo, Saman Sargazi, Habib Ghaznavi
Difficult to detect in the early stages, brain tumors seem to have baffled the researchers to a great extent, since there has been a great progression in the field of cancer research and the development of therapeutic modalities. It is noteworthy to mention that once a timely diagnosis is accompanied by effective therapy, patients would most probably enjoy an appreciable prognosis now. Today, conventional diagnostics for the detection of brain tumors include a broad spectrum of tests, such as biopsy, as well as imaging techniques, e.g. computed tomography (CT), positron-emission tomography (PET), ultrasound and magnetic resonance imaging (MRI). Through an invasive diagnostic method, biopsy sampling can provide us with invaluable information regarding the histological type of the tumor, help with classification and grading of the masses, and figuring out the aggressiveness of tumor cells. Modern imaging techniques can be employed to scan the brain for any signs of malignant tumors. However, one might argue that such diagnostics are not immediately useful for quantification of the exact volume of the tumor. That is, since excessive amounts of extracellular fluid can build-up inside the tumor, a process known as edema, the exact discrimination of tumor margins may become a more demanding task for clinicians [1,4].
Advance computer analysis of magnetic resonance imaging (MRI) for early brain tumor detection
Published in International Journal of Neuroscience, 2021
Brain Cancer is the uncontrolled growth and division of the brain cells. The cells multiply and grow uncontrollably in unusual mass of tissue is called brain tumor. This is one of the most lethal groups of cancers [1]. Based on their source, the tumors may be classified as either primary or metastatic tumors. At present radiotherapy, chemotherapy and surgery in combination are the standard treatment regimens used to treat brain tumors. The early detection of such tumors has a vital role in successful treatment. The imaging techniques such as MRI, CT, Positron Emission Tomography (PET), Magnetic Resonance Spectroscopy (MRS) and Single-Photon Emission Computed Tomography (SPECT) [2] are usually used to fetch the information about brain tumors thereby assisting in diagnosis and further treatment. The combinations of various imaging techniques are used to make available the minute information in detail.