Stereotactic body radiation therapy (SBRT)—a technique for delivering precise high dose external beam radiation—can be used to target metastatic lesions in the spine. But treating certain spinal lesions can be challenging given their proximity to the spinal cord and nerve roots. In a presentation that won second place for trainee oral presentations at the recent UW Carbone Cancer Center Research Retreat, Jacob Witt, a UW radiation oncology resident, outlined a new MRI-guided SBRT approach for spine metastases that potentially offers “higher confidence in terms of what we’re treating and, importantly, what we’re not treating.”
The study compared treatment plans for nine patients using two different radiation therapy systems: Varian TrueBeam and ViewRay MRIdian Linac. The latter features an MRI guidance system that enables monitoring of tumors and surrounding tissues during treatment.
Both systems produced similar, high-quality treatment plans. The ViewRay treatment plans did, however, have better dose gradients. The ViewRay system also offers the ability to monitor and to automatically turn off the treatment beam if the target volume moves outside the specified treatment boundary. This produces a “potentially safer” treatment in certain cases, Witt says.
“The study looked at a small patient set, but it has paved the way for us to perform spine SBRT using the ViewRay system, which we now do pretty routinely,” Witt says.
Witt was awarded funds to travel to scientific conferences for placing second at the research retreat. “It was great working on the project, and I was happy to present it and to be part of an event that captures the phenomenal scope of research taking place at the UW Carbone Cancer Center.”