September 16, 2019 — At the 2019 American Society for Radiation Oncology (ASTRO) annual meeting, being held Sept. 15-18 in Chicago, Varian announced Ethos therapy, an artificial intelligence (AI)-driven holistic solution designed to increase the capability, flexibility and efficiency of radiotherapy. This new solution is designed to deliver an entire adaptive treatment in a typical 15-minute timeslot, from patient setup through treatment delivery.
Adaptive therapy provides the ability to alter the treatment plan based on tumor and anatomical changes. The goal is to better target the tumor, reduce dose to healthy tissue and potentially improve overall outcomes.
The streamlined workflow of Ethos therapy is enabled by its AI-driven planning and contouring capabilities. The physician defines their clinical intent from predefined templates and the initial treatment plan is generated based on the physician's intent. The treatment plan is adapted in response to the variability of the tumor's shape and cellular characteristics, along with fluctuations in the tumor's position due to changes in nearby organs. The ability of Ethos to deliver on-couch adaptive treatment puts the patient at the center of care.
Ethos therapy offers the use of multimodality images — including magnetic resonance (MR), positron emission tomography (PET) and computed tomography (CT) — and daily iterative cone beam computed tomography (CBCT) images at the console. By providing an up-to-date view of the patient's anatomy, Ethos therapy provides clinicians the confidence to make more informed adaptive treatment decisions. The solution is built on Varian's latest treatment delivery technology, and provides fast imaging and treatment delivery without compromising quality.
"Ethos therapy will enable our physicians to better visualize the changes in a patient's anatomy and quickly adapt the therapy accordingly to help provide better treatments to patients," said Poul Geertsen, M.D., Ph.D., head of radiotherapy, Department of Oncology at Herlev and Gentofte Hospital, Copenhagen, Denmark. "We have already delivered the first Ethos therapy treatment, and our clinical staff was impressed by the capabilities and the ability to deliver this advanced treatment in a typical timeslot."
To advance the worldwide adoption of intelligent adaptive therapy, Varian formed the Adaptive Intelligence Consortium in April 2019. Participants include clinicians and scientists from leading cancer clinics across the globe. The consortium will lead clinical trials to develop evidence-based clinical protocols for Ethos therapy.
Ethos therapy has received CE mark and is currently U.S. Food and Drug Administration (FDA) 510(k) pending and not for sale in all markets.
Watch the 2019 ASTRO VIDEO: Artificial Intelligence Driven Adaptive Radiotherapy System Begins Treating Patients — Interview with David Sjostrom, Ph.D., deputy chief physicist, Herlev Hospital
For more information: www.varian.com
December 11, 2025 
