As many cancer patients and doctors would attest, treatment for the aggressive disease can be just as physically taxing as the disease itself. At the University of Iowa Department of Radiation Oncology, new software has been installed with the purpose of better targeting tumors and reducing radiation exposure for the patient.
The medical center is the first in North America to enter the next phase of MR-Linac technology, a system that was installed there in 2019. This “software update” has so far only been implemented by two other medical centers in the world – the IRCCS Ospedale Sacro Cuore Don Calabria in Italy and UMC Utrecht in the Netherlands – and is known as Comprehensive Motion Management (CMM). It uses software that automatically turns the radiation beam on and off during treatment to account for any movement of the tumor.
“That’s the exciting part of this,” Said Dan Hyer, Ph.D., medical physicist and professor in the UI Department of Radiation Oncology. “Previously, we weren’t able to constantly monitor the position of the tumor in real time.”
Mr. Hyer is responsible for the clinical implementation of the CMM technology, which UI Health Care has been utilizing to treat patients since fall 2023. The medical center had volunteered to be a “pilot site” for the new technology – sharing feedback with Elekta, the company that created MR-Linac.
According to Mr. Hyer, radiation therapists who operate the system go through several days of training.
“We use hands-on mock scenarios with a ‘phantom,’” Mr. Hyer explained. “Think of a box that has moving targets that represent tumors. We can see them moving and just practice.”
In real-world scenarios, CMM is being used primarily for abdominal and thoracic tumors, according to Mr. Hyer.
“It really makes targeting of the tumors much improved,” said Dr. Bryan Allen, associate professor, chair and DEO of the UI Department of Radiation Oncology. “For example, lung cancer. As we breathe, tumors are going to move… With the MR-Linac we’re able to monitor the movement before each treatment.”
Historically, the movement of a tumor would be monitored the week before treatment and used as a factor when calculating the “margin” that could be put around the tumor while administering the treatment, Dr. Allen explained.
“We can now shrink down how big of expansion we need to have to monitor these tumors and treat them adequately,” he said. “That decreases how much of the normal surrounding [tissue] we have to treat. So this is really improving the patient’s care by decreasing the radiation dose to the surrounding normal tissue structures, decreasing the toxicity.”
The time it now takes to treat each patient with the new technology is the only “catch,” according to Dr. Allen. Each CMM treatment lasts 45 minutes to an hour.
“Normally, our machines can get through 20 to 30 patients, or more, per day,” he said. “Now we try to keep it to about 10 to 15… But our goal is to be able to provide Iowans with the best cancer care possible, and this technology is helping us do that.”
Memorial Sloan Kettering, a cancer center with multiple locations in New York and New Jersey, is set to be the next pilot site for CMM technology, according to Mr. Hyer.
