CERN’s European science lab is home to researchers who regularly employ particle physics to question our understanding of the universe. They also use their skills to expand the limits. Cancer treatment.
Here, physicists work with giant particle accelerators to explore ways to extend the reach and fight cancer radiation therapy.
Roberto Corsini, the facility coordinator at CERN, stands beside a large linear particle accelerator. It consists of a 40-meter long metal beam with tubes wrapped in aluminum foil at one end and an array of measuring instruments protruding from colorful wires.
The research here, he told AFP during a recent visit, is aimed at creating very high energy beams of electrons – the negatively charged particles in the nucleus of an atom – that eventually could help to combat cancerous cells more effectively.
Corsini said that they are currently researching a “technology for accelerating electrons to the energies needed to treat deep-seated cancers.”
This idea involves using these very high energy electrons (VHEE), along with a new promising treatment method called Flash.
Reducing ‘collateral damage’
This new method delivers radiation dose in fractions of a second, rather than the current one that can take several minutes.
It has been proven that this can have the same damaging effect on the targeted tumor, but it causes less damage to surrounding healthy tissue.
Benjamin Fisch, CERN knowledge transfer officer, stated that traditional radiation therapy can create collateral damage.
According to him, the FLASH treatment has a short but powerful effect on cancer cells while also reducing the toxicity of healthy tissue.
FLASH was used for the first time on patients in 2018. The FLASH protocol is based upon medical linear accelerators that are currently available, linacs. These provide low-energy electron beams of approximately 6-10 MeV.
Because the beams are so low in energy, they cannot penetrate deeply. This means that the highly-effective treatment can be used only on superficial tumors such as skin cancer.
CERN’s physicists now collaborate with the Lausanne University Hospital, (CHUV), to develop a FLASH delivery device that can accelerate electrons up to 100 to 200 MeV. This makes it possible for the technique to be used for more difficult-to reach tumors.
‘Game-changer’
Deeply-seated cancer tumors that cannot be treated with chemotherapy or surgery are often considered to be terminal.
Professor Jean Bourhis, chief of CHUV’s radiology division, stated to AFP that “it is the ones we don’t treat at the moment which are the targets.”
It could be a game-changer for certain cancers, which can account for up to one-third the cases of cancer.
FLASH, which has a much lower effect on surrounding tissue than other methods, may be able to remove tumors that have been found in the brain and near other vital organs.
Bourhis stated that it may not be possible to eliminate the deaths caused by stubborn cancer tumors from history, but at least there will still be an opportunity for more treatments, if it succeeds.
‘Compact’
The challenge is to make the accelerator small enough to fit in a hospital.
At CERN, a large gallery has been dedicated to housing the CLEAR accelerator, which requires 20 meters to push the electrons up to the required energy level – and another 20 meters to condition, measure, and deliver the beam.
Corsini argued that CERN has the ability to accelerate in a smaller space.
CHUV is developing a prototype that will do the same job, but with a machine measuring 10 meters in length.
Corsini explained that the “compact solution” reduces costs, lowers power consumption, and is easy to put into a hospital, without needing to build a new building.
Construction of the prototype will begin in February. Clinical trialsBourhis indicated that the 2025 start could occur “if all goes smoothly.”
