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What Happens During Radiation Therapy for Acute Lymphocytic Leukemia (ALL)

You will receive radiation treatments either as an outpatient or as a patient inside the hospital. If you’re having treatment directed at just a small part of your body, you can likely do this as an outpatient. If you’re getting ready for a stem cell transplant, you will have the treatments as an inpatient.

Preparing for radiation

To prepare for your treatment, you will have a session called a simulation. During this session, your radiation therapist determines which position you’ll need to be in during treatments. Your doctor will want to make sure that the radiation is pointed at the exact same spot each time. This is called your treatment field or treatment port. First you find a comfortable position and the therapist determines where the radiation needs to go. Then the radiation therapist marks your body with ink that won’t wash off right away in the shower.

On the days you get radiation

On the days you receive radiation treatment, you’ll lie on a table while the machine is placed over you. You may have to wear a hospital gown. The experience is much like that of getting an X-ray, only longer. It takes about 15 minutes to complete. However, you should plan on being there for about an hour.

At the start of the treatment session, a radiation therapist may place blocks or special shields to protect parts of your body that don’t need to be exposed to radiation. The therapist then lines up the machine so that radiation is directed to the spot that was marked during the simulation. When you are ready, the therapist leaves the room and turns the machine on. You may hear whirring or clicking noises while the radiation is being given. During the session, you will be able to talk to the therapist over an intercom. You can’t feel radiation, so the process will be painless. Also, you will not be radioactive afterward.

When you get total body irradiation

If you’re having total body irradiation as part of a stem cell transplant, you stand in a special machine or lie down on either your stomach or your back. Special shields protect your organs, such as your lungs, heart, and kidneys, from high-dose radiation.


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