Before the beginning of radiation therapy
- Radiation therapy
- Before the beginning of radiation therapy

Before the beginning of radiation therapy
Before the beginning of radiation therapy
First visit: Meeting with your radiation oncologist
Before starting radiation therapy, you will meet with your radiation oncologist. They will take the time to explain your treatment plan, potential side effects, available strategies to anticipate or mitigate them, and the steps leading up to your first radiation therapy session. Feel free to ask any questions you have about this treatment.
Second visit: Implantation of gold or platinum seeds
In some treatment centers, 3 to 4 gold or platinum seeds are implanted into the prostate to allow for precise localization during radiation therapy treatments. This enables the radiation oncologist and technologists to better visualize your prostate, which may slightly move between each session, and precisely target it with the beam. This procedure is performed using an ultrasound device inserted through the rectum (similar to the one used during the biopsy you had).
Called reference markers, the seeds will remain in your prostate permanently, but will not cause any issues or side effects.
- An antibiotic will be prescribed to prevent infections. You should take it the day before the visit, on the day of the visit, and the day after.
- To prepare for this visit, you will also need to have a rectal enema of the “Fleet” type on the same morning.
Third visit: Simulation of an external radiation therapy session
Simulation is a planning session conducted before the first external radiation therapy session. It ensures that the radiation will be directed exactly to the same location at each session.
Treatment plan: During this visit, the medical team examines the inside of your body using an imaging device, the scanner. This examination is called a scan or computed tomography (CT) scan. The scan precisely delineates the region of your body that will be treated and aims to avoid reaching parts that are not affected. This is called the “treatment plan.”
For this visit and throughout all your treatments, your bladder must be full. Instructions will be provided to guide you.
Positioning:
A technologist determines the exact position you must be in during all treatments. If necessary, they will suggest accessories to help you maintain the desired position. Immobilization devices are specially designed to adapt to the individual’s shape.The prostate can indeed move slightly within the pelvis, depending on the volume of feces or urine in the bladder and rectum. Your healthcare team will endeavor to minimize prostate movement by asking you to follow the same daily schedule for bladder filling and rectum emptying. If everything meets the standards, the plan will be approved, and your treatment can begin.
Skin marking: Next, they will tattoo small points on your skin to serve as reference points throughout the treatment.
Verification and first treatment
Initially, technologists will meet with you to discuss the treatment steps. Feel free to ask YOUR questions.
This final visit verifies that the area to be treated aligns with the treatment plan. You will assume the position you will be in during treatments and will have the necessary accessories to maintain your position.
Then you will receive your first treatment immediately.
Additional Information - Before the beginning of radiation therapy
Sources and references
Last medical and editorial review: April 2024. See our web page validation committee and our collaborators by clicking here.