Pitfalls in the diagnosis of brain tumours

European Journal of Nuclear Medicine and Molecular Imaging, 2001

Cancerous transformation entails major biochemical changes including modifications of the energy metabolism of the cell, e.g. utilisation of glucose and other substrates, protein synthesis, and expression of receptors and antigens. Tumour growth also leads to heterogeneity in blood flow owing to focal necrosis, angiogenesis and metabolic demands, as well as disruption of transport mechanisms of substrates across cell membranes and other physiological boundaries such as the blood-brain barrier. All these biochemical, histological and anatomical changes can be assessed with emission tomography, X-ray computed tomography (CT), magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS). Whereas anatomical imaging is aimed at the diagnosis of brain tumours, biochemical imaging is better suited for tissue characterisation. The identification of a tumoural mass and the assessment of its size and vascularisation are best achieved with X-ray CT and MRI, while biochemical imaging can provide additional information that is crucial for tumour classification, differential diagnosis and follow-up. As the assessment of variables such as water content, appearance of cystic lesions and location of the tumour are largely irrelevant for tissue characterisation, a number of probes have been employed for the assessment of the biochemical features of tumours. Since biochemical changes may be related to the growth rate of cancer cells, they can be thought of as markers of tumour cell proliferation. Biochemical imaging with radionuclides of processes that occur at a cellular level provides information that complements findings obtained by anatomical imaging aimed at depicting structural, vascular and histological changes. This review focusses on the clinical application of anatomical brain imaging and biochemical assessment with positron emission tomography, single-photon emission tomography and MRS in the diagnosis of primary brain tumours, as well as in follow-up.

Neuroradiology plays an essential part in the clinical management of patients with brain tumors [1]. Magnetic resonance imaging (MRI) and, to a lesser extent, computed tomography (CT) are the cornerstones for the diagnosis, definition of extent, detection of spread and follow-up of residual or recurrent tumor [2]. The purpose of this presentation is to discuss basic and advanced neuroradiological techniques that have been developed in the examination and management of patients with brain tumors. Until recently, neuroradiological techniques were used to characterize cerebral neoplasms by: • Definition of the exact tumor location (intra-or extra-axial, supra-or infratentorial) [3,4,5]; • Demonstration of anatomy in various planes; • Display of differences in tissue density (MDCT); • Display of differences in MRI signal intensity between normal and abnormal brain tissue; • Use of contrast media to demonstrate tumor vascularity (cerebral arteriography) or to detect breakdown of the bloo...

Acta Neurochirurgica, 1995

Arquivos de Neuro-Psiquiatria, 2009

IP Innovative Publication Pvt. Ltd., 2018

Introduction: A cerebral lesion refers to any type of abnormal tissue found in the brain, particularly in the cerebral cortex. The cerebrum is responsible for allowing voluntary movements within the human body. Cerebral tumors arise from tissue throughout the brain. Neuroglial cells mainly consist of astrocytes, oligodendrocytes and ependymal cells. These cells provide shelter and maintenance for neurons. About half of the primary CNS tumors derive from glial cells. Aims and Objectives: To study the lesions of cerebrum with age and sex incidence and to find the incidence between neoplastic and non-neoplastic lesions and correlation with radiological appearance and histopathological findings of the lesions. Materials and Methods: A present study including of 150 cases of cerebral lesions. All surgical biopsies were taken at department of Neurosurgery and then send for the histopathology examination in department of Pathology of Smt. N.H.L. Municipal Medical College attached with Sheth V.S. General Hospital, Ahmedabad, Gujarat from July 2011 to June 2013. Results: Out of these total 150 biopsies, 100 were diagnosed as neoplastic lesions and 50 were diagnosed as non-neoplastic lesions. Among the neoplastic lesions, majority cases were of Gliomas (82%). Among the non-neoplastic lesions, majority cases were of infectious origin (60%). Out of total 82 cases of gliomas, 64 were of astrocytic Gliomas (78%). The peak age incidence for patients with neoplastic lesions was the 4th and 5th decade while that for benign lesions was 1st and 3rd decade. The male to female ratio was 2.7:1. Summary and Conclusion: Among the 100 neoplastic lesions most common was Gliomas. Among the glioma, most common was the Astrocytoma (78%) which was followed by the oligodendroglioma (11%) and then Ependymoma (6%). Overall male: female ratio was 2.7:1 in the patient with Glial tumors. Out of 50 non neoplastic cerebral lesions, 30 (60%) were of infectious origin. Keywords: Astrocytoma, Cerebral lesions, Glioma, Histopathology examination.

Journal of Pathology of Nepal, 2020

Gliomas; IDH; 1p/19q-codeletion; Astrocytic tumours comprise the majority of central nervous system tumours and they have been traditionally graded as recommended by World Health Organization on the basis of atypia, mitoses, microvascular proliferation and necrosis. The 2016 WHO classification of diffuse gliomas incorporates both molecular and histological criteria to categorize these tumours to better predict behavior. A layered diagnostic format is now the recommended approach with the WHO grade being assigned on histological criteria to be supplemented by molecular characterization once the result of isocitrate dehydrogenase is available. The presence of 1p/19q-codeletion has now been included in the definition of oligodendrogliomas. Oligoastrocytomas have now almost vanished as an entity because they are classified as either astrocytomas or oligodendrogliomas after molecular testing. Tests have to be modified in resource limited settings to reach a molecular diagnosis based on n...

Journal of Health and Allied Sciences NU, 2022

Background Central nervous system (CNS) tumors are relatively rare. However, brain tumors are one of the leading causes of cancer-related morbidity and mortality. Accurate histopathologic diagnosis and molecular diagnostics are critical for managing these patients. Histopathology plays a vital role in diagnosis, but clinical and radiological information is also crucial while evaluating brain tumors. Materials and Methods A cross-sectional observational study was performed for a period of 1 year in the pathology department of a tertiary hospital. All the brain biopsies sent for histopathological analysis were analyzed, and among which five brain biopsy tissue posing the diagnostic dilemma in conventional histopathology were included in the study. Immunohistochemistry was performed wherever necessary. Results During the study period, we encountered 32 cases of brain biopsy. Five cases posing diagnostic challenges in histopathological diagnosis were included in the study. Expert opinio...

Arquivos Brasileiros de Neurocirurgia: Brazilian Neurosurgery, 2016

Background: Accurate differentiation of brain infections from necrotic glioblastomas (GBMs) may not always be possible on morphologic MRI or on diffusion tensor imaging (DTI) and dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI) if these techniques are used independently. Purpose: To investigate the combined analysis of DTI and DSC-PWI in distinguishing brain injections from necrotic GBMs. Study Type: Retrospective. Population: Fourteen patients with brain infections and 21 patients with necrotic GBMs. Field Strength/Sequence: 3T MRI, DTI, and DSC-PWI. Assessment: Parametric maps of mean diffusivity (MD), fractional anisotropy (FA), coefficient of linear (CL), and planar anisotropy (CP) and leakage corrected cerebral blood volume (CBV) were computed and coregistered with postcontrast T 1-weighted and FLAIR images. All lesions were segmented into the central core and enhancing region. For each region, median values of MD, FA, CL, CP, relative CBV (rCBV), and top 90 th percentile of rCBV (rCBV max) were measured. Statistical Tests: All parameters from both regions were compared between brain infections and necrotic GBMs using Mann–Whitney tests. Logistic regression analyses were performed to obtain the best model in distinguishing these two conditions. Results: From the central core, significantly lower MD (0.90 3 10 23 6 0.44 3 10 23 mm 2 /s vs. 1.66 3 10 23 6 0.62 3 10 23 mm 2 /s, P 5 0.001), significantly higher FA (0.15 6 0.06 vs. 0.09 6 0.03, P < 0.001), and CP (0.07 6 0.03 vs. 0.04 6 0.02, P 5 0.009) were observed in brain infections compared to those in necrotic GBMs. Additionally, from the contrast-enhancing region, significantly lower rCBV (1.91 6 0.95 vs. 2.76 6 1.24, P 5 0.031) and rCBV max (3.46 6 1.41 vs. 5.89 6 2.06, P 5 0.001) were observed from infective lesions compared to necrotic GBMs. FA from the central core and rCBV max from enhancing region provided the best classification model in distinguishing brain infections from necrotic GBMs, with a sensitivity of 91% and a specificity of 93%. Data Conclusion: Combined analysis of DTI and DSC-PWI may provide better performance in differentiating brain infections from necrotic GBMs. Level of Evidence: 1 Technical Efficacy: Stage 2

Journal of Neuro-Oncology, 2008