Advances in Neuro-Oncology Imaging Techniques

Abstract

Background: Central nervous system (CNS) tumors are a rare but devastating malignancy, often robbing patients of the basic quality of life. Despite advances in our understanding of the CNS tumor disease processes, the prognosis for patients with CNS tumors remains poor. Better characterization and diagnostic and monitoring approaches are necessary to assist in diagnosis and treatment of CNS tumors. One important tool in the neuro-oncology armamentarium is the use of advanced imaging techniques. Methods: We searched PubMed using the keywords neuro-oncology imaging, pseudoprogression, molecular imaging, and biomarkers. We limited our search to full-text English articles and identified other relevant articles from the reference lists of previously identified articles. Results: Advances in imaging techniques have allowed investigators to explore various imaging modalities, from tumor characterization to differentiating pseudoprogression from tumor progression. Better imaging can result in better diagnostic approaches, greater and safer resection techniques, and improved monitoring of tumor progression. Conclusion: This review highlights advances in neuro-oncology imaging techniques and their clinical utility in the treatment and management of primary brain tumors.

Physiological Imaging Methods for Evaluating Response to Immunotherapies in Glioblastomas

“…Readers are referred to excellent review articles about these methods with specific applications to neuro-oncology [ 21 , 82 , 83 ]. In brief, analysis of diffusion MR imaging data provides several parameters such as apparent diffusion coefficient (ADC), mean diffusivity (MD), fractional anisotropy (FA), coefficient of linear (CL), planar (CP) and spherical (CS) anisotropies.…”

“…Since immunotherapies can result in delayed responses, imaging methods can prevent responsive patients from discontinuing a possibly beneficial treatment and similarly can aid non-responsive patients from continuing a potentially harmful and ineffective treatment. Physiologic imaging methods such as diffusion and perfusion imaging as well as amino acid and reporter gene-based positron emission tomography (PET) provide valuable information about tumor biology and microenvironment [ 19 , 20 , 21 ]. Several studies [ 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ] have reported the potential of these imaging techniques in the evaluation of treatment response to CCRT and antiangiogenic therapies in GBM patients, suggesting that these techniques can also aid in assessing treatment response to immunotherapies.…”

The Molecular Effects of Ionizing Radiations on Brain Cells: Radiation Necrosis vs. Tumor Recurrence

“…In the event of a brain tumor, clinical manifestations should prompt neuroimaging [28]. The best diagnostic tool to evaluate CNS neoplastic lesions is represented by MRI, which has largely replaced computed tomography (CT), although the latter could still be used in patients with contraindications to MRI or as a quick screening modality [29,30]. In general, in the case of brain tumors surgical resection is the first step when possible and only then radiation therapy follows with or without combined chemotherapy [31].…”

Neuroimaging Studies Evaluating Effective Therapies for High-Grade Glioma

“…Advanced MRI and PET imaging techniques are increasingly gaining the interest of not only researchers but also clinicians, as they have the ability to assist in the identification of biomarkers with the above mentioned ideal characteristics. 34,338 However, key to the identification of neuroimaging biomarkers, which provide robust metrics for patient stratification and for the prognostic evaluation of treatment response, is the standardisation of image acquisition, processing and analysis protocols. 34,338 The has emerged only in the last decade to address the need for better approaches to comprehensively characterise heterogeneous tumours, such as brain, breast, head and neck, and prostate cancers.…”

“…34,338 However, key to the identification of neuroimaging biomarkers, which provide robust metrics for patient stratification and for the prognostic evaluation of treatment response, is the standardisation of image acquisition, processing and analysis protocols. 34,338 The has emerged only in the last decade to address the need for better approaches to comprehensively characterise heterogeneous tumours, such as brain, breast, head and neck, and prostate cancers. 339 Radiomics has the potential to push the current clinical limits of the prognostic ability of radiological datasets, thereby becoming a powerful tool to support clinical decision-making in the era of personalised medicine.…”