Classification of CNS Tumours 2021 (PDF)

CLASSIFICATION OF THE TUMOURS OF THE CNS DR TEMBA MUDARIKI  Learning Outcomes Understanding the Significance of the WHO Classification of Tumours Appreciating the global standard provided by the WHO Classification of Tumours for understanding and categorizing...

CLASSIFICATION OF THE TUMOURS OF THE CNS DR TEMBA MUDARIKI  Learning Outcomes Understanding the Significance of the WHO Classification of Tumours Appreciating the global standard provided by the WHO Classification of Tumours for understanding and categorizing tumours based on histological and molecular characteristics. Recognizing the importance of regular updates to incorporate new scientific discoveries, advancements in diagnostic techniques, and changes in the understanding of tumour biology for improving diagnostic accuracy, guiding treatment decisions, and fostering research in oncology. Appreciating the Significance of the 2021 Update for CNS Tumours Understanding the specific impact of the 2021 update on CNS tumours, highlighting the incorporation of novel entities, refinement of existing categories, and the integration of molecular parameters into the classification for more precise and comprehensive diagnosis and treatment strategies.  Learning Outcomes Understanding the Overview of the 2021 WHO Classification of CNS Tumours Grasping the importance of the fifth edition of the WHO Classification of CNS Tumours, which represents a significant milestone in the field of neuro-oncology by incorporating the latest advancements in understanding CNS tumour biology and emphasizing the importance of molecular parameters in classification. Understanding the changes and additions introduced in the update, including the refinement of diagnostic criteria, redefinition of existing categories, and integration of updated grading criteria based on histological and molecular features. Recognizing the General Changes in CNS Tumour Classification Understanding the significant changes brought about by the 2021 update, including the reshaping of the landscape of CNS tumour classification, evolution of tumour nomenclature, gene and protein nomenclature, evolution of tumour grading, and introduction to novel diagnostic technologies.  Learning Outcomes Specific Changes in Tumour Types Grasping the specific changes introduced in the classification and characterization of gliomas, glioneuronal tumours, and neuronal tumours, reflecting the evolving understanding of the molecular and genetic underpinnings of these tumour types for more precise diagnosis and management. Understanding the Diagnosis, Classification, Staging, and Treatment of Gliomas Understanding the multi-faceted approach to diagnosing gliomas, integrating clinical evaluation, neuroimaging, histopathological analysis, and the significance of molecular markers in subtyping gliomas. Grasping the staging of gliomas based on histological and molecular features, as well as the potential for aggressive growth and invasion. Understanding the treatment and management of gliomas, including surgical, radiation, and chemotherapy approaches, as well as emerging immunotherapy and targeted therapies.  Learning Outcomes Implications for Clinical Practice and Research Recognizing the implications of the 2021 WHO Classification of CNS Tumours for clinical practice, including personalized treatment approaches, prognostic value, and the potential for clinical trial design. Understanding the impact on research, including the identification of novel targets, deeper understanding of tumour biology, and the potential for predictive biomarkers and their impact on treatment selection and patient responses. Future Directions and Areas of Continued Research Appreciating the avenues for future research and continued exploration, including the need for further molecular subtyping, continued research into targeted therapies and immunotherapy, biomarker discovery, and the importance of conducting clinical trials that incorporate refined molecular and histological classification of gliomas.  Background of the WHO Classification of Tumours  Globally recognized standard for the classification of tumours  Framework for understanding and categorizing various types of tumours based on their histological and molecular characteristics  Update is crucial for clinicians, pathologists, and researchers in the field of neuro- oncology  Personalized treatment strategies and improved patient outcomes  Fifth edition of the classification specifically focused on CNS tumours  Introduces novel entities, refines existing categories, and incorporates molecular parameters into the classification Overview of the 2021 WHO Classification of CNS Tumours Significance of the WHO Fifth Edition  Latest advancements in our understanding of CNS tumour biology  Incorporating molecular and genetic insights  Importance of molecular parameters in the classification of CNS tumours  Integrated histomolecular approach  More precise framework for diagnosing and managing CNS tumours Overview of the Changes and Additions  Addition of novel entities  Reclassification of certain tumour types based on molecular characteristics  Refinement of diagnostic criteria  Redefinition of existing categories  Addition of new diagnostic entities based on molecular findings  Incorporation of updated grading criteria for certain tumour types Overview of the 2021 WHO Classification of CNS Tumours Explanation of the Organizational Structure of the Classification  Designed to provide a systematic framework for categorizing CNS tumours  Histological and molecular characteristics Includes sections dedicated to different tumour types Detailed descriptions of diagnostic criteria Molecular features Relevant prognostic factors General Changes in CNS Tumour Classification Introduction to General Changes Encompass a wide array of updates improving  Accuracy  Precision of tumour diagnosis and classification  Patient care Focus on CNS Tumour Taxonomy Refined taxonomy for CNS tumours Latest understanding of their molecular and genetic characteristics Redefining and categorizing tumour types based on their distinct molecular profiles  Often have implications for prognosis and treatment selection Evolution of CNS Tumour Nomenclature Nomenclature for CNS tumours has evolved Reflect advances in our understanding of their underlying biology Renaming of certain tumour types Reclassification of tumours based on molecular and genetic features  General Changes in CNS Tumour Classification Gene and Protein Nomenclature for CNS Tumour Classification Incorporation of gene and protein nomenclature into CNS tumour classification important Highlighting specific genetic alterations and protein expression patterns Integral to the characterization and classification of CNS tumours Evolution of CNS Tumour Grading Changes in the grading of CNS tumours Reflecting advancements in our understanding of tumour behaviour and prognosis  Evolution involves refining grading criteria based on histological and molecular features  Providing a more accurate assessment of tumour aggressiveness and potential clinical outcomes NOS (Not Otherwise Specified) and NEC (Not Elsewhere Classified) Diagnoses May address the NOS and NEC diagnoses Aiming to minimize their use by providing more specific diagnostic entities based on histological and molecular characteristics Introduction to Novel Diagnostic Technologies Novel diagnostic technologies Integration of advanced imaging modalities Molecular profiling techniques Other innovative diagnostic tools that enhance the accuracy and specificity of tumour diagnosis  Specific Changes in Tumour Types Focus on Gliomas, Glioneuronal Tumours, and Neuronal Tumours 2021 update of the WHO Classification of CNS Tumours, several specific changes  Classification and characterization of gliomas  Glioneuronal tumours Changes reflect the evolving understanding of the molecular and genetic underpinnings of these tumour types  Gliomas  Glioneuronal Tumours  Neuronal Tumours  Gliomas The 2021 update introduces refined criteria for the classification of gliomas Emphasizing the integration of molecular parameters alongside histological features. This includes the incorporation of specific genetic alterations Mutations in IDH (isocitrate dehydrogenase) genes, 1p/19q codeletion status, and TERT (telomerase reverse transcriptase) promoter mutations, Stratify gliomas into distinct subtypes with prognostic and therapeutic implications. Update may introduce changes in the grading of gliomas Aligning with the updated diagnostic criteria based on histological and molecular features. Shift reflects the growing importance of a combined histomolecular approach in the classification of gliomas  Glioneuronal Tumours The 2021 update includes revisions in the classification and characterization of glioneuronal tumours Emphasizing the integration of molecular parameters to refine diagnostic criteria and subtyping. This involves the incorporation of specific genetic alterations and molecular profiles Distinguishing different subtypes of glioneuronal tumours, contributing to improved diagnostic accuracy and prognostication.  Neuronal Tumours The 2021 update addresses revisions in the classification of neuronal tumours Focusing on the integration of molecular parameters to refine diagnostic criteria and subtyping. This involves the incorporation of specific genetic alterations and molecular profiles that aid in distinguishing different subtypes of neuronal tumours Enabling more precise diagnosis and classification. Gliomas: Diagnosis, Classification, Staging, and Treatment Diagnosis of Gliomas Diagnosing gliomas involves a multi-faceted approach  Combination of clinical evaluation  Neuroimaging  Histopathological analysis Diagnostic process  Thorough neurological examination  Imaging studies such as magnetic resonance imaging (MRI) and computed tomography (CT) scans  Biopsy or surgical resection may be performed to obtain tissue for histopathological analysis.  Histopathology plays a crucial role in determining the specific subtype of glioma, as different subtypes have distinct histological characteristics Gliomas: Diagnosis, Classification, Staging, and Treatment Histopathological Classification of Gliomas Histopathological analysis of gliomas involves examining tissue samples  Microscope to identify characteristic features such as cell morphology  Nuclear atypia  Mitotic activity  Microvascular proliferation  Necrosis Examination allows pathologists to classify gliomas into specific subtypes astrocytomas, oligodendrogliomas, and mixed gliomas Immunohistochemical staining for specific markers such as GFAP (glial fibrillary acidic protein)  Oligodendrocyte transcription factor (OLIG2) aids in distinguishing between different subtypes of gliomas.  Molecular Markers and Glioma Subtyping Histopathological features, molecular markers play a crucial role in subtyping gliomas  The presence of mutations in isocitrate dehydrogenase (IDH) genes  Loss of heterozygosity of chromosomes 1p and 19q  Expression of the Ki-67 proliferation marker Further classify gliomas into distinct subtypes  Presence of an IDH mutation and 1p/19q codeletion is characteristic of oligodendrogliomas  The absence of these mutations and the presence of TERT promoter mutations are more commonly associated with astrocytomas.  Staging of Gliomas Gliomas are staged based on the World Health Organization (WHO) grading system Categorizes tumours into grades I to IV based on their histological and molecular features Their potential for aggressive growth and invasion Grade I and II tumours are considered low-grade Grade III and IV tumours are classified as high-grade The Ki-67 proliferation marker, reflects the rate of cellular proliferation  Often used to assess tumour aggressiveness  Incorporated into the grading process  Higher Ki-67 labelling indices are associated with more aggressive and higher-grade gliomas  Treatment and Management of Gliomas Surgery Surgical resection is often the initial step in the treatment of gliomas Aiming to remove as much of the tumour as possible while minimizing damage to healthy brain tissue Advances in neurosurgical techniques, including image-guided surgery and awake brain mapping  Have improved the safety and efficacy of tumour resection. Radiation Therapy  Following surgery, radiation therapy may be recommended  To target any remaining tumour cells and reduce the risk of recurrence  Techniques such as intensity-modulated radiation therapy (IMRT) and stereotactic radiosurgery allow for precise delivery of radiation to the tumour while sparing healthy brain tissue.  Treatment and Management of Gliomas Chemotherapy Chemotherapy, often in the form of oral or intravenous medications May be utilized as an adjuvant treatment to target residual tumour cells Primary treatment for inoperable or recurrent gliomas Use of targeted therapies  Drugs that specifically inhibit molecular pathways implicated in glioma growth, continues to evolve. Immunotherapy and Targeted Therapies Emerging treatments such as immunotherapy and targeted molecular therapies are being investigated for their potential in treating gliomas.  Harness the body's immune system  Target specific molecular pathways involved in tumour growth  New avenues for personalized treatment approaches.  Treatment and Management of Gliomas Supportive Care and Symptom Management Gliomas and their treatments can cause neurological symptoms and impact overall well-being. Palliative care, supportive therapies, and symptom management strategies are an essential part of the comprehensive care plan for patients with gliomas Focusing on maintaining quality of life and managing treatment-related side effects.  Implications for Clinical Practice and Research Clinical Practice: Personalized Treatment Approaches Integrating histological and molecular features enables more precise diagnosis and classification Personalized treatment approaches tailored to the specific subtype and molecular profile of the glioma. Targeted and effective treatments. Prognostic Value Incorporation of molecular parameters, such as IDH mutations, 1p/19q codeletion status, and TERT promoter mutations Provide valuable prognostic information, aiding in treatment decision-making and patient counselling. Clinical Trial Design: Target specific molecular pathways Implications for Clinical Practice and Research Research: Identification of Novel Targets Developing targeted therapies and immunotherapies that exploit the specific molecular vulnerabilities of different glioma subtypes. Understanding Tumour Biology: The mechanisms underlying tumour initiation, progression, and treatment resistance. Predictive Biomarkers: Potential to revolutionize treatment selection and improve patient responses to therapy. Future Directions and Areas of Continued Research Molecular Subtyping Further research is needed to refine and expand the molecular subtyping of gliomas  Identifying additional molecular markers and genetic alterations that can further stratify gliomas into distinct subtypes with unique biological behaviours and therapeutic vulnerabilities. Targeted Therapies Identifying and validating new molecular targets can lead to the development of more effective and personalized treatment approaches for patients with gliomas. Future Directions and Areas of Continued Research Immunotherapy Immune checkpoint inhibitors and chimeric antigen receptor (CAR) T-cell therapy, in the treatment of gliomas is a promising area of research. Understanding the immune microenvironment of gliomas and identifying immunotherapeutic targets is crucial for advancing this field. Biomarker Discovery Discovery and validation of predictive biomarkers that can guide treatment selection and predict response to therapy. Biomarkers for treatment response, disease progression, and patient outcomes are crucial for advancing precision medicine in glioma management. Clinical Trials Evaluate the efficacy of targeted therapies, immunotherapies, and combination treatments tailored to the specific molecular subtypes of gliomas.