What is the purpose of dexamethasone in brain tumor-related edema?

• A. To reduce peritumoral edema and improve neurologic symptoms
• B. To decrease intracranial pressure drastically
• C. To eradicate tumor cells
• D. To prevent infection

Answer: (A)

Dexamethasone is used in brain tumor–related edema because it rapidly decreases vasogenic edema around the tumor. It stabilizes the blood-brain barrier and reduces capillary permeability, which limits fluid leakage into the surrounding brain tissue. This reduction in edema lessens the mass effect of the tumor and quickly improves neurologic symptoms such as headaches and focal deficits. It is not a tumor-killing drug, so it won’t eradicate tumor cells, and it isn’t used to prevent infection. While lowering edema can help with intracranial pressure, the main purpose here is symptom relief through edema reduction, not drastic ICP change. Use is usually short-term with careful tapering to minimize steroid side effects, and patients should be monitored for hyperglycemia, infection risk, and other steroid-related issues.