Before & During Treatment

What to Expect Before and During Treatment


This CT scan is used to help create a treatment plan which is individualized to your body. The simulation may take up to 45-60 minutes. A customized mold may be made to fit your body, or you may be asked to place your arms in a special frame. The therapist will also draw lines on your skin with a marker. These lines need to stay on your skin throughout your radiation treatment, but are not permanent. The special frames and marks help ensure that the radiation beams are directed at the same targets each day. Following the simulation, it will take 7 to 10 days to design your unique treatment plan.

Field localization:

This is the “dry run” before actual radiation treatments begin. At this time, x-rays are taken of the treatment “fields,” or the areas of your body where the radiation is being directed. These fields are then matched to the computerized plan that was generated based on the simulation CT scan. After the initial field localization, x-rays will be taken each week to ensure that your body is positioned correctly in the treatment machine.

First day of treatment:

You will be positioned in the machine in the same way as the time of field localization. You can expect to see red laser lights on the wall, and you may hear some noise as the radiation machine, or LINAC, is turned on and off. However, the actual radiation cannot be seen, heard, or felt. Each treatment takes 15-20 minutes. Most of this time is devoted to making sure you are positioned properly. You can help speed up your treatment by remaining as still as you can in the machine, and following all the directions that the radiation therapists give you. Your treatment will be 5-7 weeks, weekdays only, for 15-20 minutes each day. Bring a book in case there are unexpected delays.

More Information:

For more details about how radiation treatment works, we also have a patient education booklet. Please ask for this material if you have not received them.