Revolutionizing Radiation Therapy
At the NYP David H. Koch Center, an MRI-guided linear accelerator promises cancer patients more targeted treatments.
For Dr. Silvia Formenti, the most exciting aspect of the NewYork-Presbyterian David H. Koch Center is a linear accelerator with integrated magnetic resonance imaging (MRI), the MRIdian by ViewRay.
MRI enables the most precise targeting of radiation by accurately tracking the position and shape of a patient’s tumor. When internal organs move in response to respiratory and heart movement, this machine directs the treatment to precisely respond to the tumor’s change in position. The result is smaller and more precise fields of radiation, which spare the adjacent normal tissue. Best of all for patients, treatment courses can be shorter and more accurate.
The first on the East Coast, this state-of-the-art machine delivers “the classical photon radiotherapy, but in the context of MRI imaging,” says Dr. Formenti, the Sandra and Edward Meyer Chair for Cancer Research, professor and chairman of radiation oncology, and radiation oncologist in chief of NewYork-Presbyterian/Weill Cornell Medical Center, and a member of the NYP David H. Koch Center planning committee.
“The magnetic resonance imaging enables much more precision in defining the organs within the body, and with much more clarity. Also, [it offers] some functional information that you wouldn’t get with a normal CT scan and normal radiation machine. These unique characteristics enable the safe delivery of larger and more precisely targeted doses of radiation, reducing the number of visits needed to ablate a cancer.”
About two-thirds of cancer patients receiving treatment undergo a form of radiation therapy. But during a typical session, the patient’s tumors and internal organs move as a result of breathing or heartbeat. That means that although a radiologist positions the patient correctly at the start and end of the session, the radiation beam may not target the tumor as precisely as expected throughout the treatment.
“With the standard available technology, we can confirm the patient is in the correct position and verify that the organ and tumor are in the correct position before or after radiation — but not in real time,” says Dr. Formenti. The new linear accelerator improves upon this by relying on MR imaging to inform delivery of the dose only when the tumor is exactly in the position to be targeted by the radiation beam. Thus, the healthy tissues surrounding the tumor are largely spared.
What’s more, in keeping with the NewYork-Presbyterian David H. Koch Center’s patient-first ethos, “we are working very closely with the company that developed this machine to try to give the patient control of their movement,” says Dr. Formenti. “The patient will be able to see on the screen … internal movement in the body, and learn how to modify the breathing to adjust and align the target with the radiation beam. The patient becomes a partner and is in the driver’s seat. In addition to enhancing the precision and efficiency of treatment, I think it’s also going to be psychologically helpful to give back some of that control to cancer patients, who often feel somehow excluded from the management of their disease.”
In addition to the MRI-guided linear accelerator, the center will have two other linear accelerators that are capable of treating tumors with the most sophisticated techniques, including intensity modulated radiation therapy, electron beam therapy, and stereotactic body radiation therapy.