Radiation Therapy Centre Area​​


Princess Margaret Cancer Centre (Directions)

1B and 2B Floors, Radiation Therapy Treatment Centre ​


Monday - Friday: 8:00am - 6:00pm​


Call if you need to change an appointment or if you have any questions.

  • Level 1B Radiation Therapy Simulation
    Phone: 416 946 2172
  • Level 2B Radiation Therapy Treatment
    Phone: 416 946 2187

What We Do

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Cancer & COVID

Radiation therapy is one of the main methods of treating cancer. There are two ways to deliver radiation therapy.

Health Information

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          The Team

          Treating people with radiation takes a well-coordinated team. Your team at the Radiation Therapy Centre includes world-class health care professionals working to support you and your family

          Radiation Oncologists

          Radiation oncologists are doctors who specialize in treating cancer with radiation therapy. They:

          • Prescribe a treatment plan for each patient
          • Monitor your progress throughout radiation therapy treatment
          • Help identify and manage side effects of radiation therapy treatment

          Radiation Therapists

          Radiation therapists are medical radiation technologists who specialize in radiation therapy. They:

          • Develop the treatment plan with your radiation oncologist and medical physicists
          • Deliver the radiation treatment and ensure that it is accurate and precise
          • Monitor your progress and provide support and advice during your treatments

          You will see your radiation therapists every time you go for a treatment session. You can talk to them about any questions or concerns you may have, such as side effects or scheduling issues. They can also recommend other specialists and professionals when you need one.

          Medical Physicists

          Medical physicists are health care professionals who specialize in the physics of radiation therapy. They:

          • Make sure that the radiation treatment machine delivers the correct amount of radiation to the correct area of your body
          • Verify that your treatment plan is safe and precise
          • Are responsible for developing and directing quality control programs for equipment and procedures

          Oncology Nurses

          Oncology nurses are registered nurses who specialize in the care of patients with cancer. They:

          • Provide symptom management and support during your treatment
          • Deliver care and assistance during your review and follow-up appointments

          Patient Flow Coordinators

          Patient Flow Coordinators are clerical staff who specialize in coordinating radiation therapy appointments. They:

          • Schedule all radiation therapy appointments
          • Help check in patients who are having radiation therapy treatment and for clinic appointments​

          What to Expect: Radiation Treatment

          Make sure to bring:

          • Government issued health card (OHIP card)
          • Pacemaker or defibrillator card (if you have one)
          • Any medications that you normally take during the day in case your appointment is delayed


          Radiation Therapy Patient Education Videos

          Watch this series of video modules to learn about the radiation therapy process, from the planning appointment through treatment and follow-up care. You can watch all of the videos in order by clicking on the first image. You can also flip through the videos to select the one you want to watch by clicking on the images on the right side of the video screen. To return to the menu while watching a video, click on the "Flow" icon in the top right corner.

          Steps of Radiation Therapy Treatment

          Radiation therapy treatment involves several steps:

          1. CT Simulation
          2. Planning
          3. Treatment
          4. Review
          5. Follow-up


          1. CT Simulation

          CT simulations are booked Monday to Friday between 9:00 AM and 5:00 PM.

          Your CT simulation appointment is the first step in designing your personalized radiation therapy treatment plan. The simulator (a special CT scanner) takes pictures of your treatment area. Your radiation team uses these pictures to design your treatments.

          Your CT simulation appointment will take about 30 to 45 minutes.

          When you arrive:

          Check in with the Patient Flow Coordinator on level 1B of Princess Margaret Cancer Centre. The Patient Flow Coordinator will:

          • Take your photo. This helps to correctly identify you at your appointments.
          • Ask if you prefer a certain time of day for your appointments. We will do our best to meet your request, however it is not always possible.
          • Ask you about your travel and accommodation arrangements.

          During Your CT Simulation:

          Radiation therapists will perform the CT simulation. They will:

          • Position you on the simulator bed
          • Take CT images of your treatment area
          • Make immobilization devices for you, if needed.
            Immobilization devices are used to help you stay very still during your radiation therapy treatments. Patients receiving treatment to the head, neck or brain often have an immobilization device made during the simulation appointment.
          • Give you contrast medium, if needed.
            Contrast medium (usually simply called “contrast”) may be used during your CT simulation appointment to help your radiation team see your internal organs. Contrast can be given as a drink or as an injection.
          • Give you small tattoos to help position you for your treatments, if needed.
            Tattoos are used to help the radiation therapists make sure you are in the right position for treatments each time you visit. The tattoo is a small, permanent dot of ink that is injected just under your skin. It will not wash off. Usually you will need only 3 to 5 tiny tattoo dots.

          Your radiation oncologist may recommend additional simulation imaging using MRI or PET. If your radiation oncologist recommends this, we will do the MRI or PET simulation on the same day as the CT simulation.

          At the end of your CT simulation appointment we will give you a green appointment card. Bring this card each time you come to the hospital for a radiation treatment appointment.

          The Patient Flow Coordinator  will call you at home after the CT simulation to give you your first radiation therapy treatment appointment and tell you which unit to go to for treatment. Write the date and time of this appointment on the green appointment card. The first radiation therapy treatment appointment is usually booked within a week of your simulation appointment.

          2. Planning

          Treatment planning is done by your radiation team after your CT simulation appointment. Using the information gathered from the simulation, your team works together behind the scenes to design your personalized treatment plan.

          Your treatment plan includes:

          • The number and types of beams needed to treat the area
          • The number of radiation treatments you will need
          • The amount of radiation you will receive at each treatment appointment

          Treatments plans are different for each person. Some treatment plans are given in only 1 day and others may be given over several weeks. On average, radiation treatments are given daily for 4 to 5 weeks.

          3. Treatment

          Treatments are given Monday to Friday between 8:00 AM and 6:00 PM.

          If a statutory holiday occurs during your treatment, your schedule will be adjusted so that you still get the right number of treatments.

          When you arrive:

          Check in at the reception desk on level 1B or 2B of Princess Margaret Cancer Centre.

          • For units 1 to 18 go to level 2B
          • For unit 19 go to level 1B

          The Patient Flow Coordinator will show you how to swipe your green appointment card and will check you in. Your first treatment session will usually last about 30 minutes. Your other treatment sessions will last about 15 to 20 minutes.

          During Your Treatment:

          When it is time for your treatment, the radiation therapists will position you on the treatment bed. Once you are positioned, the bed will be moved under the linear accelerator (the radiation machine). The therapists will check measurements and take images to make sure you are in the right position each day.

          The radiation therapists will not stay in the treatment room with you during treatment. The radiation therapists can see you through a camera while you are receiving treatment and will make sure you’re okay. There is an intercom in the room that you can use to speak to the radiation therapists whenever you need to.

          The linear accelerator will not touch you during the treatment sessions. It may move around your body during the sessions to give you radiation from different angles.

          Radiation treatment doesn’t hurt. You will not see or feel anything during the treatment. You may hear clicking or whirring noises from the machine. These noises are perfectly normal. Radiation treatment does not make you radioactive.

          When the radiation treatment is finished, the radiation therapists will come back into the treatment room. They will remove any immobilization devices and help you off the bed. They will also be able to help you with any side effects you may be having.

          Each radiation treatment room has a CD player for music. You are welcome to bring in your own music to listen to while you have your treatment.

          Your radiation therapist will give you a schedule for your radiation therapy treatment appointments each week. The therapist will review the schedule with you. You can also see your UHN appointments by logging in to myUHN Patient Portal. Learn more about myUHN Patient Portal »

          4. Review

          Your review appointment is a weekly visit with your radiation oncologist and oncology nurse to review how your treatment is going and to take care of any side effects you may have. It is important to ask questions and to tell your doctor how you are feeling during this appointment. You may want to talk about:

          • Any questions or concerns you have about your treatment
          • Whether you have felt any changes since starting treatment
          • Symptoms or side effects you may be experiencing
          • Prescription renewals
          • How you are coping with treatment
          • Whether you have any difficulties getting to your appointments
          • Whether you have any financial difficulties paying for your medications or other supplies

          Before each clinic appointment (in-person or virtual), you will be asked to answer questions about your health and wellbeing. Use eCheck-In to report your symptoms and concerns to your healthcare team.​​

          Your review appointment will be on the weekly schedule that your radiation therapist gives you. Your review appointment could be on level 1B, level 2B or in your clinic. When you arrive, check in at the reception desk on level 1B, level 2B or in your clinic.

          Review appointments usually take about 20 minutes.

          We do our best to stay on time. Unfortunately, your appointment may be delayed by unforeseen circumstances. We recommend that you come prepared for delays. For example, make sure that your arrangements for things like babysitting, elder care and parking can accommodate a longer than expected appointment.

          • The Princess Margaret has a free child-care service called The Magic Castle. The Magic Castle takes care of children up to 12 years old while their parent or guardian goes to an appointment at Princess Margaret.  Find out more about the Magic Castle »

          5. Follow-Up

          During the last week of your radiation therapy treatment, you will receive a follow-up appointment to come back and see your radiation oncologist. The follow-up appointment usually takes place 4 to 8 weeks after you finish your treatment.​​

          What to Expect: Brachytherapy (Internal Radiation)

          Make sure to bring:

          • Government issued health card (OHIP card)
          • Pacemaker or defibrillator card (if you have one)
          • Any medications that you normally take during the day in case your appointment is delayed

          Brachytherapy treatment (or internal radiation therapy treatment) uses sealed ​radioactive material placed near or into the tumour area inside your body. Brachytherapy treatment can also be used in combination with external beam radiation therapy treatment for some cancers.

          The way brachytherapy treatment is delivered depends on the area of the body that needs to be treated.


          High Dose Rate (HDR) Brachytherapy

          HDR brachytherapy treatment may be used to treat some gynecologic, urologic, lung and esophageal tumours.

          HDR brachytherapy uses a special device called an applicator to deliver a sealed radioactive source to the area of the body that needs to be treated. The applicator is inserted and stays in place for the treatment, which usually takes only a few minutes. The applicator is removed after each treatment session. Treatment does not make you radioactive.

          Most people who receive HDR brachytherapy get 1 to 3 treatments, given over a few weeks. HDR brachytherapy treatment is usually given on an outpatient basis (you may not have to stay overnight at the hospital).

          Eye Plaque Brachytherapy

          Eye plaque brachytherapy is used to treat some cancers of the eye (ocular cancer). For eye plaque brachytherapy, a surgeon places radioactive seeds into a special device called a plaque. It is sewn over the tumour on the outside of your eye. The plaque contains radioactive seeds that direct radiation into the tumour in your eye. It stays in place usually up to 7 days. Most people are able to return home while the plaque is in place. At the end of the treatment period, the plaque is surgically removed and no radioactivity remains in your body.

          Prostate Permanent Seed Implant Brachytherapy

          For some men with prostate cancer, radiation treatment may be given using permanent seed implant brachytherapy. Radioactive seeds are implanted into the prostate during an operation. These seeds stay in place in the prostate forever. The seeds release small doses of radiation slowly over time, until the radioactivity gradually fades away.

          Most people who have this type of treatment are able to go home the same day as the operation. ​

          QuickStart Breast Radiation Therapy Program
          Magnetic Resonance guided Radiation Therapy (MRgRT)

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          Last reviewed: 10/4/2022
          Last modified: 2/27/2024 8:53 AM
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