Extreme dose rate proton therapy

Fast facts

• Official title: Extreme dose rate proton therapy – reducing the side-effects for brain cancer treatments
• Lead researcher: Dr Jan Schuemann 
• Where: Massachusetts General Hospital and Harvard Medical School
• When: September 2019 – February 2022
• Cost: £120,000 
• Research type: Academic, Pre-clinical, Primary brain tumours 
• Grant round: Expanding Theories
  

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What is it?

Radiation therapy (or radiotherapy) uses controlled and targeted high energy beams of charged particles to destroy the tumour cells. Conventional radiation therapy uses beams of X-rays or photons, whereas proton beam therapy uses beams of protons.

When these high-energy particles (photons or protons) reach the tumour, they transfer their energy to the tumour cells causing damage to the cells’ DNA. Once DNA has accumulated enough damage due to repeated doses of radiation, and is therefore unable to repair itself, the cells die. The problem with this is that repeated doses of radiation are thought to increase the risk of unwanted side-effects.

Previous studies have shown that delivering radiotherapy extremely rapidly can dramatically reduce side-effects. Radiation therapy that delivers the same dose of radiation in a much shorter period of time is called extreme dose radiation (EDR). EDR therapy has not been tested using proton beams, and that’s where this innovative research project comes in.

The research team, led by Dr Schuemann, will use pre-clinical models to test EDR proton therapy with the aim of establishing a treatment regimen that’s effective and well-tolerated by people. They’ll compare EDR to conventional radiation delivery and look for any differences in side-effects, specifically looking into the effects on cognition and motor control.

In addition, the team will share their learnings on how EDR works and how it reduces side-effects to improve outcomes and help shape the future of proton beam research.

Why is it important?

Radiation therapy is a key part of treatment for many cancers, and sometimes the only treatment available. This is especially true for people diagnosed with a brain tumour.

Compared to conventional radiotherapy, proton beam therapy reduces radiation exposure to surrounding healthy tissue. Because the brain is a very sensitive and complex organ this reduced radiation exposure is particularly important. That’s why brain tumours are one of the main diseases treated using proton beam therapy.

When conventional (photon) therapy is used, the beam goes through the tumour and also effects the healthy brain on the far side. This resulting side-effects include issues with: cognition, memory, motor control and speech.

Proton beam therapy is different because doctors can stop the beam in the tumour treatment area so that it doesn’t go further into the brain.

Proton beam therapy is still an emerging treatment and further research is needed to understand the best way to use this therapy. This research is helping to do that, aiming to determine a radiation treatment regimen that will further reduce side-effects, compared to conventional radiotherapy, and improve quality of life for those receiving treatment.

Who will it help?

This research aims to further our understanding of EDR therapy and how it has the potential to help future users of proton beam therapy, including both adults and children diagnosed with brain tumours.

Research into EDR is vital, as this treatment will have the ability to control tumour growth significantly reduced side-effects. In particular, EDR treatments could help people diagnosed with more aggressive tumours, as it’ll allow doctors to increase the amount of radiation delivered to the tumour, potentially improving survival while minimising unwanted tissue damage and side-effects.

In addition, EDR treatment could be of particular benefit to children with brain tumours. These tumours often occur during an important period of a child’s development, which means that side-effects caused by treatment will last longer and result in significant long-term effects on their quality of life.

Milestones

Achieved

We’re looking forward to seeing the achievements of this group when the project starts.

Upcoming

• The research team will set-up the study and calculate the radiation dosage required for EDR therapy.
• They’ll test this dosage in pre-clinical models and evaluate the side-effects on cognition and motor control.
• The research team will also collect samples from the pre-clinical models to further understand how EDR therapy kills the tumours.

If you have any questions about this, or any of our other research projects, please contact us on research@thebraintumourcharity.org