New Model May Simplify High-Dose Radiosurgery Planning

COLUMBUS, Ohio – There is yet no straightforward way to determine the optimal dose level and treatment schedules for high-dose radiation therapies such as stereotactic radiation therapy, which is used to treat brain and lung cancer, or for high-dose brachytherapy for prostate and other cancers.

Radiation oncologists at the Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC-James) may have solved the problem by developing a new mathematical model that encompasses all dose levels.

Typically, radiation therapy for cancer is given in daily, low doses spread over many weeks. Oncologists often calculate the schedules for these fractionated, low-dose treatment courses using a mathematical model called the linear-quadratic (LQ) Model. The same calculation model is used to evaluate radiation response, interpret clinical data and guide clinical trials.

“Unfortunately the LQ Model doesn’t work well for high-dose radiation therapy,” says co-author Dr. Nina Mayr, professor of radiation oncology at the OSUCCC-James. “Our study resolves this problem by modifying the current method to develop the Generalized LQ (gLQ) Model that covers all dose levels and schedules.”

If verified clinically, the Generalized gLQ Model could guide the planning of dose and schedules needed for the newer radiosurgery and stereotactic radiation therapy and high-dose brachytherapy procedures that are increasingly used for cancer patients, she says.

source: Ohio State University Medical Center