Radiation therapy to the brain

Stereotactic radiosurgery is often used when cancer has only spread to a few sites in the brain. Side effects vary depending on where the radiation is aimed, and usually become most serious 1 to 2 years after treatment. Talk with your radiation oncologist about what to watch for and when to call for help.

Sometimes the whole brain is treated with radiation when cancer has spread into many sites. This may also be done to prevent cancer from spreading to the brain. Whole-brain radiation can cause these side effects:

• Headaches
• Swelling of the brain
• Hair loss
• Nausea
• Vomiting
• Extreme tiredness (fatigue)
• Hearing loss
• Skin and scalp changes
• Trouble with memory and speech
• Seizures

Medicines are usually given to prevent brain swelling, but it’s important to let your doctor know about headaches and other symptoms. Delayed effects (usually 1 or 2 years later) of whole-brain radiation may be caused by death of brain tissue. These delayed effects can include serious problems such as memory loss, stroke-like symptoms, and poor brain function.