Jacinta Bowler
For those with cancer, Australia will have another option by the end of 2025 – a proton therapy centre at the South Australian Health and Medical Research Institute (SAHMRI).
But while many South Australians know the centre is coming, it’s worth understanding how photon therapy actually works, and how it is different to current radiation therapy.
“It is a type of radiation, the only difference is that normally we use gamma rays, but with proton therapy, it’s accelerating a ‘heavy’ charged particle,” says Associate Professor Michael Penniment AM – a radiation oncologist and the director of the Australian Bragg Centre for Proton Therapy at SAHMRI.
A proton is a hydrogen atom with no electrons, which makes it ‘positive’. The protons are sped up faster and faster in a machine called a cyclotron, which looks a bit like a small version of the Large Hadron Collider in Switzerland.
“Your typical cyclotron will accelerate those protons to about two thirds of the speed of light,” Penniment adds.
Regular radiation therapy with gamma or X-rays, pumps radiation through a small area of the body. It works well in areas where there is a large tumour, because the radiation can be directed towards that area. However, some radiation can leak to outside the tumour, which can damage normal cells in the process.
This is acceptable in most circumstances, but sometimes this extra dose of radiation will create problems. Some examples include if a tumour is right next to a spinal cord, those people with brain cancer, or children whose organs and bodies are still developing.
Proton therapy though can be incredibly accurate – down to the millimetre. So, radiation doesn’t also affect normal tissue, instead specifically zapping the cancer.
Importantly, it’s not necessary for every type of cancer, there are specific cases where it can lead to better outcomes.
“Most of the time, it’s about whether it’s going to lead to less side effects and better survivorship,” said Penniment.
The building for the proton therapy centre at SAMHI has just been completed, but the team have a lot to do before the 2025 opening. The team will first be putting in the cyclotron and other equipment and then ensuring that the devices are millimetre accurate.
“The building’s finished, so it’s all looking good. You need the building be dust free and air conditioned before we can start moving the machinery in,” said Penniment.
“Most of the machinery is in Boston at the moment. That’s been tested, and that’ll start coming over and it will start getting installed.
“There will probably be some stuff installed before the end of the year, but basically February, March it’ll be really racking up, and then there will be a good year of us installing.”
Dr Penniment joined Cosmos on stage at Science City on the topic of Cancer. You can find out more and watch the full event here.