Pituitary Tumor: Radiation Therapy
Radiation is often used to treat pituitary tumors that come back after surgery. If you are not healthy enough to have surgery, radiation may be used to shrink a tumor that is causing problems. It may also be used to treat pituitary tumors that cause symptoms that medicine can’t help. If a tumor is very large, the surgeon may first remove as much as safely possible. Then the rest of the tumor will be treated with radiation.
Radiation works very slowly on pituitary tumors. It may take up to 10 years to control a tumor's growth and hormone production.
How is radiation therapy given?
Before radiation starts, imaging scans are taken. These are used to clearly outline the size and shape of the tumor. The radiation beams are controlled to fit this shape and kill the tumor. This helps limit damage to nearby healthy tissue.
Radiation for pituitary tumors can be given in different ways. Conventional radiation is given from a machine outside the body. The radiation is directed at the pituitary. Treatment is given 5 times a week for several weeks.
Other types of radiation that may be used include:
Stereotactic radiation. This form of radiation precisely targets the tumor. It directs beams at the tumor from several different angles. Treatment may be given in 1 session. This method can safely give a higher radiation dose. It can also radiate the tumor and not the entire brain. This kind of radiation can prevent a mild decrease in mental sharpness that can happen many years after conventional radiation. But it can’t be used if the tumor is near important nerves, such as the optic nerve.
Proton beam radiation. This type of radiation therapy uses a different type of beam. It can focus right on the pituitary tumor. This may limit radiation to nearby healthy tissues. But it is only done in a few medical centers because special equipment must be used.
It's common to have a mold, mask, or frame made. This will hold you in the exact same position for each radiation treatment.
Side effects of radiation for pituitary tumors
Talk to your doctor about what you might feel like during and after radiation therapy. Side effects may get worse as treatment goes on, but can be treated.
Side effects often get better or go away over time after treatment ends. The side effects of radiation therapy include:
Skin in the treated area that is irritated, dry, red, and blistered like a sunburn
Hair loss on the part of your head that the radiation passes through to reach the tumor
Feeling tired or weak
Swelling in the brain that causes headaches, confusion, seizures, and speech problems
Damage to the pituitary gland that makes it stop working
Talk to your doctor about what side effects you can expect. Also talk about what can be done to prevent or ease them. Ask your doctor what symptoms to watch out for. Know when you should call your healthcare team.
Some long-term side effects of radiation may not show up for many years after you finish treatment. These depend on the dose and location of the radiation. These also depend on how many times you had the treatment. Ask your doctor what you may expect.
March 21, 2017
Gersten, Todd, MD,Stump-Sutliff, Kim, RN, MSN, AOCNS