Snapshot A 47-year-old man presents to the emergency department complaining of a headache. His symptoms have been progressively worsening over the course of week. He does not have a past medical history of headaches and has noticed some weakness in his left upper extremity. Physical examination is notable for 4/5 power throughout the left upper extremity. MRI brain with gadolinium demonstrates a white matter mass lesion with patchy enhancement. Neurosurgery is consulted for surgical resection. Introduction Definition malignant tumor arise from oligodendrocytes most commonly affects the frontal and temporal lobe and is slow growing ETIOLOGY Pathophysiology genetic mutations lead to dysregulated and abnormal cellular proliferation Epidemiology Demographics typically 25-45 years of age Presentation Symptoms/physical exam clinical manifestations depend on where the tumor arises from seizure headaches personality changes Imaging MRI brain with and without contrast indication imaging study of choice findings enhancing mass calcifications are characteristic absence of contrast enhancement does not exclude the diagnosis Studies Histopathology and molecular testing indication confirms the diagnosis findings histopathology "fried egg" cellular appearance round nuclei within a clear cytoplasm molecular testing IDH1 or IDH2 mutation and 1p/19q co-deletion Differential Other malignant brain neoplasm differentiating factors based on histological findings e.g., glioblastomas will have pleomorphic tumor cells surrounding a central area of necrosis Treatment Surgical resection indication initial step in management obtain tissue for histopathology and molecular testing radiation therapy and chemotherapy is typically given as well Complications Seizures Neurological deficits Prognosis Poor