About Radiation Therapy and Radiation Therapists

Radiation Therapist performing therapy on a patientRadiation therapy involves using high-energy radiation beams in a finely-focused way. These beams are strong enough to damage or kill cancer cells and stop them from dividing and spreading. Radiation therapy is often used to treat or cure cancer or it can be used to provide relief from symptoms (in cancers that have spread to other parts of the body). The therapy can be given externally by machines (external beam radiation) or internally by placing small amounts of radioactive materials into body cavities or tissues (brachytherapy). In order to destroy cancerous tissue, radiation therapy involves exposure to higher doses of radiation than are required for diagnostic imaging. So it's vital that the radiation be precisely targeted and the patient's exposure carefully monitored.

Radiation therapists are responsible for acquiring imaging information to plan the radiation beams, generating individual treatment plans for a patient and making sure it is delivered accurately on a daily basis, whilst providing ongoing support and care. They work with the radiation oncologist, medical physicist and oncology nurse, playing a vital role in the treatment and care of cancer patients. 

Radiation therapists (MRTT) are regulated health care professionals and registered with the College of Medical Radiation Technologists of Ontario (CMRTO). Registration with the CMRTO assures the public that the MRTT has met the entry to practice requirements as defined by the registration regulations made under the MRT Act. All MRTTs are required to successfully complete an approved program in medical radiation sciences, successfully complete an approved examination and meet other requirements as defined by the CMRTO. Through its quality assurance program the CMRTO also ensures that MRTTs continue to maintain their competence.

The innovative clinical practice of radiation therapists at Princess Margaret is diverse, and includes involvement in areas such as intensity modulated radiation therapy (IMRT), image guided radiation therapy (IGRT), stereotactic radiation therapy, brachytherapy, research, clinical trials, patient education, staff education and informatics.

Approximately half of all cancer patients will require radiation therapy at some point in their cancer care. Princess Margaret's Radiation Medicine Program (RMP) is structured to provide patients with the best advice, assessment, treatment and follow-up care available.

The RMP is made up of three core disciplines: radiation oncology, radiation therapy and radiation physics. Closely integrated into teams, we participate in education, research and clinical care with a host of nurses, dietitians, physiotherapists, and social workers. More than 350 people make this one of the largest radiation programs in North America.

At Princess Margaret, the clinical specialist radiation therapist (CSRT) is an advanced practice role. They are registered radiation therapists who have acquired advanced knowledge and skills through a combination of experience and training in caring for individuals and families with cancer, and Master's level education. They integrate theoretical, research and practical knowledge to exercise sound judgment across complex and varying social, cultural and environmental organizational contexts making a unique and significant contribution to the timely provision of excellent radiation therapy treatment and patient care in the cancer care system.

Patient Education Videos

For more information on radiation therapy, please watch our patient education videos at Step-by-Step Guide to the Radiation Therapy Treatment Process.

The video also explains how radiation works in the body and how the team works together to deliver the highest quality treatments.


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