Michael Weller (Switzerland)
University Hospital Zurich Department of NeurologyAuthor Of 2 Presentations
GLIOMAS
- Michael Weller (Switzerland)
WORK IN PROGRESS: CHANGES TO WHO BRAIN TUMOR CLASSIFICATION
- Michael Weller (Switzerland)
Abstract
Abstract Body
The WHO classification of central nervous system (CNS) tumors had been revised in 2016 to include for the first time molecular biomarkers that are important for tumor classification and clinical decision making. Thereafter, the cIMPACT-NOW (Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy – not officially WHO) formed to further refine CNS tumor classification through specific recommendations that addressed issues of classification still controversial in 2016. Several cIMPACT-NOW proposals have shaped the new 2021 WHO classification of brain tumors.
Mutations in the isocitrate dehydrogenase (IDH) 1 or 2 genes continue to play a major role in glioma classification beyond 2021. Among IDH-mutant gliomas, loss of ATRX expression identifies IDH-mutant astrocytomas without necessity for 1p/19q codeletion testing. Conversely, etection of a 1p/19q codeletion in an IDH-mutant glioma defines an oligodendroglial tumor. The nomenclature for IDH-mutant glioblastoma has been changed to astrocytoma, IDH-mutant, WHO grade 4, with CDKN2A homozygous deletion representing a molecular marker for these tumors. IDH-wildtype astrocytomas that lack microvascular proliferation or necrosis but exhibit telomerase reverse transcriptase promoter mutation, epidermal growth factor receptor amplification and/or a +7/-10 genotype are now classified as IDH-wildtype glioblastoma. H3.3 G34-mutant diffuse hemispheric gliomas have been proposed as a new entity separate from IDH-wildtype glioblastoma.
The new WHO classification increases the diagnostic accuracy and refines clinical care by changing treatment recommendations, e.g. for patients with IDH-wildtype astrocytomas showing molecular features of glioblastoma. It also has major implications for clinical trial design, notable inclusion and exclusion criteria for ongoing and upcoming clinical trials.
Presenter of 2 Presentations
GLIOMAS
- Michael Weller (Switzerland)
WORK IN PROGRESS: CHANGES TO WHO BRAIN TUMOR CLASSIFICATION
- Michael Weller (Switzerland)
Abstract
Abstract Body
The WHO classification of central nervous system (CNS) tumors had been revised in 2016 to include for the first time molecular biomarkers that are important for tumor classification and clinical decision making. Thereafter, the cIMPACT-NOW (Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy – not officially WHO) formed to further refine CNS tumor classification through specific recommendations that addressed issues of classification still controversial in 2016. Several cIMPACT-NOW proposals have shaped the new 2021 WHO classification of brain tumors.
Mutations in the isocitrate dehydrogenase (IDH) 1 or 2 genes continue to play a major role in glioma classification beyond 2021. Among IDH-mutant gliomas, loss of ATRX expression identifies IDH-mutant astrocytomas without necessity for 1p/19q codeletion testing. Conversely, etection of a 1p/19q codeletion in an IDH-mutant glioma defines an oligodendroglial tumor. The nomenclature for IDH-mutant glioblastoma has been changed to astrocytoma, IDH-mutant, WHO grade 4, with CDKN2A homozygous deletion representing a molecular marker for these tumors. IDH-wildtype astrocytomas that lack microvascular proliferation or necrosis but exhibit telomerase reverse transcriptase promoter mutation, epidermal growth factor receptor amplification and/or a +7/-10 genotype are now classified as IDH-wildtype glioblastoma. H3.3 G34-mutant diffuse hemispheric gliomas have been proposed as a new entity separate from IDH-wildtype glioblastoma.
The new WHO classification increases the diagnostic accuracy and refines clinical care by changing treatment recommendations, e.g. for patients with IDH-wildtype astrocytomas showing molecular features of glioblastoma. It also has major implications for clinical trial design, notable inclusion and exclusion criteria for ongoing and upcoming clinical trials.
Moderator of 3 Sessions
- Michael Weller (Switzerland)
- Michael Weller (Switzerland)
- Michael Weller (Switzerland)