Novel technology for in situ irradiation of tumors

Radiation therapy is an established method of cancer treatment. It works by subjecting tumor cells to ionizing radiation, damaging their genetic material and, ideally, eliminating the tumor. Researchers have long been working on methods for directing as much radiation as possible at tumors while avoiding harm to surrounding tissue, but thus far it has proven impossible to prevent damage to the skin and healthy organs when treating internal tumors.

Preventing damage to surrounding tissue

To solve this problem, Professor Anke-Susanne Müller and Professor Matthias Fuchs, from KIT's Institute for Beam Physics and Technology (IBPT), and Professor Oliver Jäkel from the DKFZ, have teamed up to develop a novel electron accelerator for radiation therapy. Existing radiation therapy devices are reaching their limits and the ways of improving them are largely exhausted, so the researchers aim to employ a new method.

We're using high-intensity laser light to accelerate electrons to nearly the speed of light over very short distances."

Professor Matthias Fuchs, KIT's Institute for Beam Physics and Technology

The electrons will be aimed directly at tumors, with the goal of destroying them. The light-driven mechanism could allow a thousandfold reduction in the size of an electron accelerator, from about a meter to less than a millimeter. The resulting device, almost as small as a hair, could be inserted into a patient's body on an endoscope.

"Tumors could be irradiated directly and with high precision from the inside without damaging healthy tissue. It's a completely new approach," Müller said, adding that it would make a different tumor treatment outcome possible as therapy could be completed with a dose of ultrashort, high-intensity pulses of radiation at a single appointment. According to Müller, initial high-dose therapy tests have also demonstrated that this kind of irradiation mobilizes the immune system, which then responds better to metastases.

Making radiation therapy accessible for everyone

Further basic research is still needed to resolve open issues, and this where Müller, with her experience in accelerator physics, and Fuchs, as an expert in high-performance lasers, are needed. Jäkel, in turn, can contribute his medical physics expertise when it comes to optimizing the technology for radiation therapy and integrating it in medical equipment.

The research team's ultimate goal is a compact irradiation unit that needs far less space, maintenance and electricity than current medical equipment - characteristics that could enable economical production and better access to radiation therapy worldwide. "Global access to such therapy has been severely limited until now due to high costs and infrastructure demands," Jäkel said. He noted that the capacity of current radiation therapy equipment is not nearly enough and that the worldwide rise in life expectancy with its accompanying increase in tumors means much more such equipment will be needed in the future.

Duringthe next two years, the UCART team will produce a demonstration unit. Later it plans to work with partners in industry to pave the way for preclinical trials leading to routine use. If all goes according to plan, at some point the new technology could be available in many medical facilities and as easy to use as X-ray machines, according to Müller. "Then cancer treatment would be accessible to a larger number of patients, from local medical practices to developing countries," she said.