RecruitingPhase IIIInterventional

The neurocognitive benefits of proton beam therapy for patients with oligodendroglioma

Oligodendroglioma is an uncommon brain tumour that often has a good long-term outlook. Standard treatment involves surgery, radiotherapy to stop tumour regrowth, and chemotherapy. However, standard radiotherapy can sometimes lead to long-term memory and concentration difficulties years later. The APPROACH study is a UK-wide clinical trial comparing standard radiotherapy with an advanced treatment called proton beam therapy. Proton beams can be focused more tightly, which may reduce the radiation dose received by healthy parts of the brain. Researchers want to see if proton beam therapy lowers the risk of long-term memory problems and improves quality of life without reducing tumour control. Participants are randomly assigned to receive either standard radiotherapy locally or proton therapy in London or Manchester (with accommodation provided). Patients are then followed for five years with memory checks, MRI scans, and health surveys.

At a glance

Status

Recruiting

Phase

Phase III

Sponsor

University of Leeds

Enrolment target

246

Start

17 Jan 2024

Estimated completion

17 Jul 2027

Brain cancer, oligodendroglioma

What is this study about?

An oligodendroglioma is a slow-growing type of brain tumour that typically responds well to treatment. The usual care pathway involves an operation to remove as much of the tumour as safe, followed by radiotherapy to stop any remaining cells from growing, and then chemotherapy. Standard radiotherapy uses high-energy X-rays (photons) given in small daily doses over about six weeks.

While standard radiotherapy is very effective at controlling the tumour, it can affect healthy brain tissue nearby. Over time, some people develop issues with memory, problem-solving, or mental processing speed. These side effects may only appear years after treatment and can make working or daily life more challenging.

Proton beam therapy is a newer, highly targeted type of radiotherapy. Because proton beams can be stopped at a precise depth, less radiation reaches healthy brain tissue. Doctors believe this could protect important areas used for memory and thinking. However, proton beam therapy is expensive and requires specialist equipment. This trial aims to discover whether proton beam therapy truly leads to better long-term brain health and quality of life compared to standard radiotherapy, helping the NHS offer the best care possible.

Key takeaways

The APPROACH study compares standard radiotherapy with advanced proton beam therapy for oligodendroglioma brain tumours.
The main goal is to see if proton beam therapy better protects memory, concentration, and quality of life over time.
Treatment lasts around six weeks, followed by standard chemotherapy and five years of regular check-ups.
Proton treatment takes place in London or Manchester with accommodation provided; standard radiotherapy is at your local hospital.
Joining the study is voluntary, and you can leave at any time without altering your standard medical care.

Who may be eligible?

This trial is open to adults aged 25 and over in the UK who have been diagnosed with an oligodendroglioma that has specific genetic markers (known as an IDH mutation and 1p19q co-deletion). Participants must be reasonably well in their daily life, recovering well from any recent brain surgery, and ready to begin radiotherapy.

People cannot take part if they have already had radiotherapy to the head or neck, or if they have previously had chemotherapy for this tumour. It is also not suitable for people with other conditions affecting memory and brain function, or those with serious kidney, liver, or blood problems that would make follow-up chemotherapy unsafe.

Because the tests used to check memory and concentration are currently only available in English, participants need to be able to complete assessments in English. Anyone who is pregnant or breastfeeding cannot join, and patients who could become pregnant or father a child must agree to use reliable contraception during and after treatment.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

I am 25 years old or older.
I have been diagnosed with an oligodendroglioma brain tumour.
My medical team has advised that I need radiotherapy now.
I have not had radiotherapy to the head or chemotherapy for this tumour in the past.
I am able to complete memory assessments in English.
I am not pregnant or breastfeeding.

Answer every question to see your result.

What does participation involve?

If you decide to take part, a computer will randomly assign you to receive either standard radiotherapy or proton beam therapy. You have an equal chance of receiving either treatment, and both are given once a day on weekdays for about six weeks. If you have standard radiotherapy, you will be treated at your local cancer centre. If you are assigned proton beam therapy, your treatment will take place in either London or Manchester, with accommodation arranged and paid for.

After radiotherapy finishes, participants usually go on to have standard chemotherapy tablets. Researchers will monitor your health for five years. This follow-up involves doing simple memory and thinking puzzles, filling in questionnaires about your daily life and well-being, having regular MRI brain scans, and giving occasional blood samples to check hormone levels. Carers will also be invited to complete short surveys about their experience.

Potential risks and benefits

Taking part may not directly benefit you compared to standard treatment, as both approaches give the same tumour-fighting radiation dose. However, your involvement could help doctors understand how to protect brain function in future patients. Radiotherapy can cause temporary side effects such as fatigue, hair thinning, headaches, skin redness, nausea, and mild swelling in the brain. Chemotherapy also carries risks like tiredness, increased chance of infections, and stomach upsets. Travelling to London or Manchester can cause disruption to your routine. Taking part is completely voluntary, and you can withdraw at any time without your normal NHS care being affected.

Locations (21)

Addenbrookes
Approximate
Cambridge, England
University Hospital Bristol
City only
Bristol, England
Charing Cross Hospital
Approximate
London, England
The Christie
Approximate
Manchester, England
Clatterbridge Cancer Centre
Approximate
Wirral, England
Guy's & St Thomas Hospital
Unverified
London, England
Maidstone Hospital
Unverified
Maidstone, England
James Cook University Hospital
Unverified
Middlesbrough, England
Queens Medical Centre
Unverified
Nottingham, England
Oxford University Hospitals
Unverified
Oxford, England
Derriford Hospital
Unverified
Plymouth, England
University Hospital Birmingham
Unverified
Birmingham, England

Common questions

Will proton beam therapy cure my tumour better than standard radiotherapy?

No difference is expected in tumour control. Both treatments deliver the exact same radiation dose to the tumour. The study is testing whether proton beams cause fewer long-term side effects on memory and thinking.

Can I choose which treatment I receive?

No. A computer assigns you to either standard radiotherapy or proton beam therapy by chance (randomisation). This is the fairest way to compare the two treatments accurately.

What happens if I need to travel for proton beam therapy?

Proton beam therapy is only available at specialist centres in Manchester and London. If you are assigned to this group, accommodation will be provided for you near the hospital for the six weeks of treatment.

What do the memory and thinking tests involve?

These are straightforward, practical tasks such as remembering words, solving simple puzzles, and answering questions. They are designed to measure your concentration, memory, and information processing speed.

Does my family member or carer have to take part?

No, their involvement is entirely optional. Carers are invited to fill out surveys about their experiences and well-being, but you can still join the study even if your carer prefers not to.

How to find out more

Jaike Belgrave

approach@leeds.ac.uk +44 (0)113 343 3275 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.