In neuropathology, a primary application of IHC for brain tumors is to determine the glial versus neuronal lineage of the tumor cells. The central nervous system contains a complex mix of cell types, and tumors can arise from glial cells (astrocytes, oligodendrocytes, ependymal cells) or neurons and their precursors. Under routine H&E staining, many of these tumors can look similar. IHC panels are essential for accurate classification, which dictates prognosis and treatment. Key markers include: 1) **Glial markers**: GFAP (glial fibrillary acidic protein) for astrocytes, Olig2 for oligodendroglial lineage. 2) **Neuronal markers**: Synaptophysin, NeuN, and MAP2 for neuronal differentiation. 3) **Proliferation markers**: Ki-67 (MIB-1) for grading. For example, positive staining for GFAP and a high Ki-67 helps diagnose a high-grade astrocytoma (glioblastoma), while co-expression of Olig2 and IDH1 mutation is characteristic of oligodendroglioma. Synaptophysin positivity is key for diagnosing medulloblastoma or central neurocytoma.

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Zambia

• ivwananji siwale – 29 pts

• Visual Pathway Lesions
• Positive and Negative Symptoms
• Hallucinations and Delusions
• Antipsychotic Medications
• Emergency: Environmental Emergencies