FLASH An innovative electron radiotherapy technology (Video: CERN)

An innovative electron radiotherapy technology

Many breakthrough applications in the medical field have resulted from developments in particle physics research. One such example is the use of very high-energy electrons (VHEE) for a frontier radiotherapy technique called FLASH radiotherapy, a highly targeted cancer treatment, capable of reaching deep into a patient’s body with fewer side-effects than traditional radiotherapy.

In September 2020, CERN and Switzerland’s Lausanne University Hospital (CHUV) announced their collaboration to develop the conceptual design of an innovative radiotherapy facility that would deliver high radiation doses in milliseconds instead of minutes. The goal being to exploit the so-called FLASH effect, wherein radiation doses administered over short time periods appear to damage tumours more than healthy tissue, potentially minimising harmful side-effects.

In June 2021, CHUV and the ISREC Foundation announced that funding had been secured, thanks to the financial support of the Biltema Foundation for the next phase of the design and construction of the facility.

In 2022, CERN, the CHUV and THERYQ (ALCEN Group, France) signed an agreement for the development of the device, which will be based at CHUV and is expected to be operational within two years. First clinical trials planned for 2025.

Using the CLIC high-performance linear electron accelerator technology, we designed a facility which is capable of treating large and deep-seated tumours in the very short timescales needed for FLASH therapy
- Walter Wuensch, project leader at CERN
FLASH image


This pioneering installation will capitalise on CERN breakthrough accelerator technology and will be based on the high-gradient accelerator technology developed for the proposed CLIC electron–positron collider. Various research teams have been performing their biomedical research related to VHEE and FLASH at the CERN Linear Electron Accelerator for Research (CLEAR), one of the few facilities available for characterising VHEE beams.

This project is partly funded by CERN's Medical Applications budget since 2020 for a duration of two years.

For more information:

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