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Radiation Therapy (RT)

Radiation therapy (also called radiotherapy) uses radiation (high-energy rays) to kill or shrink tumour cells.
What is RT?
About this treatment
Radiation therapy, or radiotherapy, is used to treat some, but not all, cancers. About half of patients with cancer get radiation therapy as part of their treatment.

Radiation therapy can be used to try to cure cancer, reduce the chance of it coming back, or to help relieve symptoms. You might have it by itself or with other treatments such as surgery, chemotherapy, or hormone therapy.

Most radiation therapy is delivered by a machine from outside of the body (external radiation therapy). Radiation therapy can also be delivered from inside the body, called internal radiation therapy or brachytherapy. Your radiation oncologist will decide which type you need.

We encourage you to watch our four, short videos about radiation therapy:


For more information, click "+" on the topics below.

 
Radiation destroys cells in the treatment area. It does this either by destroying the cell directly or by damaging its DNA so that it cannot grow anymore. Cancer cells are more sensitive to radiation than normal cells.

It is very hard to destroy cancer cells without damaging some normal cells too. Damage to normal cells causes side effects. However, normal cells can recover from radiation damage better than cancer cells.

The goal of radiation therapy is to give enough radiation to destroy the cancer cells in your body, but not enough that your normal cells cannot recover.

Find out more about radiation therapy side effects here. 

 
When deciding on your course of treatment your radiation oncologist considers:

  • Your type of cancer
  • Where it is in the body
  • Other treatments you’ve had, are having, or going to have
  • Your general health and fitness
Radiation therapy with the goal of curing cancer or reducing the chance it can come back can last between 1 to 7 weeks.

If the goal for your treatment is to relieve symptoms, you might have anything from a single treatment to 2 weeks of treatment.

Most people have one treatment daily from Monday to Friday, with a rest on weekends and holidays.

However, these scenarios can vary. For example, you might have treatment once a week for a few weeks, or more than one treatment per day. You might also have treatment on the weekend. Your doctor will confirm your treatment schedule.

Treatment appointment times are usually not the same every day. Let someone on your care team know if you need a specific time window for your appointments. They will try to accommodate, but it can be difficult depending on how busy the department is. 

 
You may feel anxious about your radiation therapy treatment. This is completely normal.

It can help to talk through any worries you have with your radiation oncologist, nurse, or radiation therapists. We also offer counselling services with health professionals. They can help you cope with emotions and concerns about your treatment.

Find out more about the other services and support programs we offer here to help you through your cancer care journey.
Having RT
Whether you have radiation therapy as part of your treatment depends on:
 
  • what type of cancer you have
  • how big your cancer is
  • if your cancer has spread or not. 
Find out more about when and where you might have radiation therapy, who gives it, and what your treatment journey might look like. 

For additional information, click "+" on the topics below.


Radiation therapy is used for two main reasons: to try to cure cancer (radical or curative) or to help control symptoms (palliative).

Your radiation oncologist will decide whether or not you should have radiation therapy as part of your treatment. It depends on what type of cancer you have, how big it is, and whether it has spread or not.

You might have radiation therapy:

  • Before surgery
  • After surgery
  • As part of a bone marrow transplant
  • Together with chemotherapy
  • By itself 

Radiation therapy is usually given as an outpatient. For external radiation therapy, you will travel to the radiation therapy department at your nearest regional cancer centre. You will go home after your treatment.

For some types of internal radiation therapy (or brachytherapy), you might have to stay in the hospital overnight. If you’re already staying in the hospital, your hospital care team will arrange your transportation to the radiation therapy department.

Some types of radiation therapy are only offered in specific regional cancer centres. If you need a type of treatment that is only offered at a centre far from home, talk to your radiation oncologist about where you can stay.

Find out more here about your options for transportation and lodging.

Doctors who specialise in treating cancer with radiation therapy are called radiation oncologists.

Your radiation oncologist works with other health professionals who have been trained in cancer treatment and care. Your health care team during your radiation treatment will include:

  • A radiation oncologist
  • Radiation therapists
  • Medical physicists (specialists who help make the radiation treatment plan)
Your primary team is responsible for designing, planning, and delivering your radiation treatment plan safely and effectively. You will see radiation therapists every day for your treatment appointments. You will see your radiation oncologist at least once during your treatment course.

Other members of your health care team may include:

  • Nurses
  • Dietitians
  • Speech language pathologists
  • Medical oncologist
  • Surgeon
  • Physiotherapists

Once you and your radiation oncologist have decided that you will have radiation therapy treatment, the planning process will start.
 
To plan your treatment your radiation oncologist needs to see where the cancer is and the area around it. Usually, this means you will have a planning CT simulation appointment in the radiation therapy department.

At this appointment, you will lie down on the CT scanner bed. The radiation therapists will position you. Please tell the radiation therapists if you are uncomfortable.  You will have to lie in this exact position each time you have your radiation treatment.

Depending on what area of your body is being treated, you may also need:

  • A mould or mask(shell) to keep you perfectly still
  • IV contrast (dye) injection to help see the cancer or blood vessels better
  • Permanent tattoos (the size of a freckle) to help put you in the right position
After the CT simulation appointment, the radiation oncologist, radiation therapists, and medical physicist will plan your treatment.

Once your treatment plan is completed, a radiation therapy clerk will call you with the date and time of your first treatment. On that day, the radiation therapists will sit down with you to explain the process and answer your questions. 

Types of RT
There are many types of radiation therapy. Depending on your cancer type, stage of your cancer and how you are feeling, the radiation oncologist will decide what type of radiation therapy is right for you. 

There are two main types of radiation:

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