GBM diagnosis typically involves a combination of methods:
- Neurological Examination: A thorough examination to assess vision, hearing, balance, coordination, strength, and reflexes.
- Imaging Tests:
- Magnetic Resonance Imaging (MRI): The primary imaging modality for diagnosing glioblastoma. MRI can provide detailed images of the brain's structure.
- Computed Tomography (CT) Scan: Sometimes used in conjunction with MRI to get a comprehensive view of the brain.
- Biopsy: A definitive diagnosis is made through a biopsy, where a small sample of the tumor tissue is removed and examined under a microscope. This can be done through:
- Molecular Testing: Genetic and molecular testing of the tumor tissue can help identify specific mutations and markers, which can inform treatment decisions. Common markers tested include:
- MGMT (O6-methylguanine-DNA methyltransferase) Promoter Methylation: Associated with better response to certain chemotherapies.
- IDH1 and IDH2 Mutations: Less common in glioblastoma but have prognostic significance.
- 1p/19q Co-deletion: Rare in glioblastoma but important for distinguishing other types of gliomas.
