Software tailors treatment parameters, personalizes dose delivery to account for anatomical changes
Radiation oncologists at the University of Maryland Marlene and Stewart Greenebaum Cancer Center are implementing a new treatment planning system that will customize radiation therapy for cancer patients over the course of their treatment. The system, known as RayStation®, will allow doctors to fine-tune the radiation dose and make other adjustments to the treatment plan as patients experience changes such as tumor shrinkage and/or weight loss.
“We are taking a step forward toward more customized radiation treatments with this capability of performing adaptive, or ‘personalized’ radiotherapy,” says William F. Regine, M.D., the Isadore & Fannie Schneider Foxman Professor and Chairman of the Department of Radiation Oncology at the University of Maryland School of Medicine and chief of radiation oncology at the University of Maryland Medical Center. “This new planning system gives us the ability to make adjustments to the initial treatment plan and tailor the treatment to the individual patient based on tumor or anatomical changes.”
Cancer patients who are treated with radiation typically receive treatments five days a week, for five to seven weeks. With most planning systems, making adjustments and determining the effect of these adjustments during the actual treatment regimen can require complex, labor-intensive computations that can interrupt or delay therapy, Dr. Regine adds. “This system provides us with a solution that avoids any such interruption or delay for the patient,” he says.
The challenge for radiation oncologists is to provide the optimum dose of radiation to the tumor while minimizing the dose to sensitive tissues and organs in the body. Certain organs, such as the spinal cord and heart, are more sensitive to radiation exposure than others. Traditional treatment planning systems require a repetitive process of planning, evaluating and modifying treatment before a patient’s therapy begins. Doctors prescribe the optimal dose to attack the tumor, and dosimetrists translate that into a treatment plan, while trying to minimize the dose to other nearby organs as much as possible. If physicians see that a sensitive organ may receive too much radiation, they must modify the treatment plan to further minimize dose to that area. With current treatment planning systems, this process can become prohibitively complex.
The system employs what is known as “multi-criteria optimization,” allowing experts to more easily use computer controls to visualize in real time the effect that any slight adjustment of dose to one organ has on all the critical nearby structures. “This technology allows us to prioritize, in real time, adjustments of dose reduction for surrounding healthy tissue or organs,” Dr. Regine says.
E. Albert Reece, M.D., Ph.D., M.B.A., vice president for medical affairs at the University of Maryland and the John Z. and Akiko K. Bowers Distinguished Professor and dean of the University of Maryland School of Medicine, says, “The radiation oncologists at the Marlene and Stewart Greenebaum Cancer are recognized not only for their research and innovation but also for the precision with which they deliver radiation therapy to patients. With advances in technology, they are able to more directly target the tumor while sparing normal, healthy tissue.”
The new system will be in full operation this spring at the Greenebaum Cancer Center and later in the year at several other hospitals in the University of Maryland Medical System.
RayStation is a registered trademark of RaySearch Laboratories AB.