There is apparently no specific approach to examine the optimal dose level and treatment schedules for high-dose radiation therapies like stereotactic radiation therapy currently. The latter is seemingly used to treat brain and lung cancer or high-dose brachytherapy for prostate and other cancers. Scientists at the Ohio State University Comprehensive Cancer Center have seemingly solved the problem by creating a new mathematical model that subsumes all dose levels.
Radiation therapy for cancer is supposedly given in daily, low doses over several weeks. Oncologists evaluate the schedules for these fractionated, low-dose treatment courses. This is mainly done with the help of a mathematical model called the linear-quadratic model. Apparently, the same calculation model is used to examine radiation response, understand clinical data and direct clinical trials.
“Unfortunately the LQ Model doesn’t work well for high-dose radiation therapy. Our study resolves this problem by modifying the current method to develop the Generalized LQ (gLQ) Model that covers all dose levels and schedules,” commented co-author Dr. Nina Mayr, professor of radiation oncology at the OSUCCC-James.
Experts share that if the Generalized gLQ model is verified clinically it may help in the planning of dose and schedules required for the newer radiosurgery and stereotactic radiation therapy. It may also help in high-dose brachytherapy methods that seem to be increasingly used for cancer patients.
“Developing proper radiation dose schedules for these promising high-dose treatments is very challenging,” Mayr quoted. “Typically, it involves phase I dose-finding studies and a long, cumbersome process that allows only gradual progression from the pre-clinical and clinical trial stages to broader clinical practice.”
The new gLQ model is anticipated to help oncologists chalk out radiation dose schedules effectively. It may assist scientists to conduct clinical trials for particular cancers rapidly and make these high-dose therapies available to cancer patients faster.
Fractionated low-dose therapy may cause damage to tumor cells during the weeks of exposure, whereas it may cause lesser damage to hardier normal cells. However, patients must visit their hospitals frequently to complete their treatment.
“Our Generalized LQ Model determines appropriate radiation levels across the entire wide spectrum of doses, from low and high, and from many to very few treatments, which is a new approach,” Mayr remarked.
High-dose therapy has seemingly become possible due to the advances in computer and radiation technology. It utilizes several beams of radiation that conform firmly to a tumor’s shape. They meet on the cancer to deliver higher total radiation levels, whereas spare normal tissues. This apparently eradicates more tumor cells in every treatment, however so far lesser treatments are required overall. This analysis is anticipated to be tested soon in clinical trials.
These findings were published in the journal Science Translational Medicine.