University of Cincinnati advances FLASH radiation therapy with new clinical trial
Collaboration with Cincinnati Children’s, Varian Medical Systems demonstrates safety of treatment
University of Cincinnati Cancer Center researchers led a first-of-a-kind clinical study showing that a cancer treatment known as FLASH, or ultra-high-dose-rate proton beam radiation therapy, safely and effectively reduced pain in patients with cancer that had spread to the bones in the chest (thoracic bone metastases).
The study was conducted in collaboration with Cincinnati Children's, Varian Medical Systems and UC Health.
The findings from the FAST-02 clinical trial were published in Radiotherapy and Oncology.
FLASH radiation therapy delivers treatment in a fraction of a second rather than minutes, up to a thousand times faster than typical radiation therapy.
Proton gantry at the Proton Therapy Center where the research took place. Photo/Colleen Kelley
FAST-02 was the first clinical trial to evaluate this therapy for bone metastases in the chest or thorax, near critical organs such as the heart and lungs. The results build on the team's earlier FAST-01 trial, which established the safety of the treatment for bone metastases in the arms and legs. By treating bone metastases near vital organs rather than in the extremities, this second trial further assessed the safety of this new treatment.
In the study, researchers used FLASH radiation therapy to treat 10 patients with different types of cancers that had spread to their bones, causing pain at disease sites in the ribs, collarbones, breastbone/sternum or shoulder blades. No serious treatment-related side effects were observed, and no moderate or severe radiation-related complications were found during follow-up. The most common side effect was mild skin changes that resolved over time.
Importantly, 75% of patients evaluated three months after FLASH reported complete pain relief at the treated site, and no patients experienced cancer spread or recurrence at the FLASH-treated site during the follow-up period.
“The significance of FAST-02 lies in our treatment sites being bone metastases within the thorax, which places them near the lungs, heart and spinal cord,” said study lead co-investigator Emily Daugherty, MD, associate professor of radiation oncology at the University of Cincinnati, a member of the University of Cincinnati Cancer Center and a UC Health radiation oncologist.
“Assessing critical organ side effects is essential for any future implementation of FLASH in deep-seated tumors. Importantly, the results continue to show that FLASH effectively controls pain with minimal side effects, and there were no serious adverse events related to the treatment."
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