For Patients
How to Prepare
Before you undergo external beam radiation therapy, your health care team guides you through a planning process to ensure that radiation reaches the precise spot in your body where it's needed. Planning typically includes:
- Radiation simulation. During simulation your radiation therapy team works with you to find a comfortable position for you during treatment. It's imperative that you lie still during treatment, so finding a comfortable position is vital. To do this, you'll lie on the same type of table that's used during radiation therapy. Cushions and restraints are used to position you in the right way and to help you hold still. Your radiation therapy team will mark the area of your body that will receive the radiation. Depending on your situation, you may receive temporary marking with a marker or you may receive permanent tattoos
- Planning scans. Your radiation therapy team may have you undergo X-rays or computerized tomography (CT) scans to determine the area of your body to be treated
- After the planning process, your radiation therapy team decides what type of radiation and what dose you'll receive based on your type and stage of cancer, your general health, and the goals for your treatment
What to Expect
External beam radiation therapy is conducted using a linear accelerator — a machine that directs high-energy beams of radiation into your body. As you lie on a table, the linear accelerator moves around you to deliver radiation from several angles. The linear accelerator can be adjusted for your particular situation so that it delivers the precise dose of radiation your doctor has ordered.
You typically receive external beam radiation on an outpatient basis five days a week over a period of at least two to 10 weeks. Treatments are usually spread out over several weeks to allow your healthy cells to recover in between radiation therapy sessions. Expect each treatment session to last approximately 10 minutes to 30 minutes. In some cases, a single treatment may be used to help relieve pain or other symptoms associated with more advanced cancers.
During a treatment session, you'll lie down in the position determined during your radiation simulation session. You might be positioned with molds to hold you in place and shields may be placed to block radiation from reaching certain parts of your body.
The linear accelerator machine may rotate around your body to reach the target from different directions. The machine makes a buzzing sound. You'll lie still and breathe normally during the treatment, which takes only a few minutes. Your radiation therapy team stays nearby in a room with video and audio connections so that you can talk to each other. You should speak up if you feel uncomfortable, but you shouldn't feel any pain during your radiation therapy session.
Results
If you're receiving radiation to a tumor, your doctor may have you undergo periodic scans after your treatment to see how your cancer has responded to radiation therapy. In some cases your cancer may respond to treatment right away. In other cases it may take weeks or months for your cancer to respond.
