Carefully lowering the MR-Linac through the roof of Sunnybrook’s Odette Cancer Centre, and into a specially constructed radiation treatment bunker, was a feat almost as massive as the six-tonne machine itself.
But you would be remiss if you thought the MR-Linac was only focused on big things. It promises to target tumours with millimetre precision.
The MR-Linac is the first and only machine in the world to combine simultaneous external-beam radiation therapy (known as a linear accelerator) and high-field strength magnetic resonance imaging (MRI), an engineering feat that allows Sunnybrook teams to locate, visualize and track tumours as they move inside the body and target radiation therapy precisely where needed. A tumour’s location is typically determined based on images prior to radiation.
Dr. Arjun Saghal, director of the Cancer Ablation Therapy Program.
Now, the slightest movements of a tumour can be pinpointed with real-time MRI guidance, sparing healthy tissue from radiation. While still in the clinical trial phase, the merging of these powerful technologies could transform radiation therapy for some of the hardest-to-treat cancers, and more common cancers, too, including pancreas and prostate.
Visionary donors, who recognized its promise and supported its research in its infancy, helped bring the MR-Linac to Sunnybrook, the first in Canada.
After securing Health Canada approval, Sunnybrook got to work beginning clinical trials.
Sunnybrook’s interprofessional team — including radiation oncologists, medical physicists, and medical radiation therapists — made history and treated the first patient in Canada on the MR-Linac in August 2019.
The team watched while the beam of radiation targeted a glioblastoma, the most common type of malignant brain tumour among adults. Witnessing the radiation hit the target meant the team could ensure pinpoint accuracy, sparing healthy tissue and adjusting for tumour changes. In the months since, this technology has been brought to 105 patients with brain cancer.
The new MR-Linac — the Elekta Unity.
Visionary donors helped bring the MR-Linac to Sunnybrook, the first in Canada.
Sunnybrook treated its first patient with prostate cancer in November 2019. As the prostate moves during treatment based on surrounding organs, the MR-Linac takes into account its daily position in relation to these organs.
Throughout these trials, the Cancer Ablation Therapy Program’s team works closely with researchers, who are using daily MRIs to determine how a tumour responds to radiation by examining the cell death or growth of each tumour. By studying this data, it is their hope Sunnybrook will be able to personalize treatment by predicting which tumour will or won’t respond to treatment. This is particularly important for cancers where there have been few advances in treatment options in years.
“Generous donors have enabled Canadians to access world-leading technologies, right here at Sunnybrook,” says Dr. Arjun Sahgal, director of the Cancer Ablation Therapy Program, whose team is assessing the technology.
“We are close to breaking barriers, and evaluating the technology and its potential to do better for the patient,” he says.
Sunnybrook is proud to have been instrumental in the development and implementation of this technology, as one of seven founding members of the MR-Linac consortium, a global research partnership to transform the future of radiation therapy.
And we’re just getting started.
