Proton beam therapy treatment for cancer

Proton beam therapy is a type of radiotherapy. Radiotherapy uses high energy X-rays whereas proton beam therapy uses a beam of high energy protons. Protons are small parts of atoms.  

You can find out more about radiotherapy on our information page.

One of the benefits of proton beam therapy is that because the beam is so accurate it sometimes means they can give you a higher dose of treatment as it won’t impact the tissue around the area being treated.  

This also means you might have fewer long-term side effects as a result of the treatment. 

Proton beam therapy can be used to deliver radiation to very specific parts of the body to treat cancer. This means very little or no radiation affects normal tissue around the area being treated. 

Proton beam therapy is given using a machine called a ‘gantry’. The machine rotates 360 degrees around you which means it can accurately aim the proton beam at the area which needs to be treated.  

Proton beam therapy isn’t suitable for everyone, at the moment it can only be used on a limited range of cancer types. Your consultant will talk to you about whether it’s an option for you and they’ll be the ones to refer you if it’s appropriate for your treatment.  

How long your treatment takes will depend on the area that is being treated. You’ll be given more information about this during your assessment visit. 

Every course of proton beam therapy is different depending on your diagnosis and the type of cancer that is being treated. The minimum course for proton beam therapy is usually three weeks and the maximum course is eight and a half weeks. During this time you will have treatment five days a week. Treatment will be on weekdays, not weekends.  

The tests you have before you start proton beam therapy will depend on what your consultant requests. Some of the tests you have to have might include CT scans, MRI scans, PET scans, a lumbar puncture and a renogram (kidney scan). Depending on your diagnosis and what other treatment types you’ve had your sight, hearing and teeth may also be checked.  

You won’t feel any pain while you’re having proton beam therapy. Nothing will touch any part of your body directly. The machine will make some noise and there is sometimes a smell which can be a bit unpleasant. Sometimes people see flashing lights before their eyes during the treatment. Not everyone will experience these but they are all completely normal and safe side effects of the treatment. If you have any questions about what it will be like in the room during your treatment you can always ask your care team.  

The side effects you might experience will depend on which part of your body is being treated. Your care team should explain any potential side effects you might experience before your treatment starts. 

A lot of the common side effects of external radiotherapy are similar to those you might experience after having proton beam therapy. They can be quite mild and don’t last too long, but they can still be unpleasant and uncomfortable. Short-term side effects settle down typically between 6-8 weeks. 

Side effects can include: 

• sore skin in the area you had treated with proton beam therapy. It might be dry and itchy and may also peel 

• losing your hair. But it’s important to note that you’ll only lose hair in the area of your body that you have had treated 

• you will be using a lot of energy to help your body recover so there’s a chance you’ll feel really tired after having proton beam therapy. Traveling to and from hospital every day can also make you feel tired 

• you might experience some nausea (feeling sick) or diarrhoea after treatment. If you do have either of these side effects you can speak to your doctor who should be able to give advice on what to do 

• this might also affect your appetite too. If you’re not feeling great then you might not want to eat anything either. Try and eat small things when you can to keep your energy levels up  

Sometimes, cancer treatments can have side effects that don’t get better once the treatment has finished. These vary depending on where your cancer is but, if you’re worried, talk to your doctor or nurse about possible long-term side effects before you start any treatment. 

Find out more about side effects on our radiotherapy information page.

It’s important to keep in regular contact with your care team about how you’re feeling and any side effects you’re experiencing. They will be able to prescribe medication that can help with some of your symptoms like anti-sickness medication, pain relief or certain creams for sore skin.  

Exercise when you feel up to it and rest when you feel you need to. Try and keep up a healthy lifestyle so you can avoid any breaks in treatment. 

You can also ask to be put in touch with other support staff and allied health professionals who can help you. Allied health professionals work both in and out of hospitals and in some cases might come to your home. They can help with movement or mobility difficulties, visual problems, advice on what to eat and nutrition, communication and everyday activities.  

You can find out more about each allied health professional role on the NHS website.  

If you’re having sex you should use barrier types of contraception, like condoms and dams, to protect you and your partner and to also stop you getting pregnant. You need to let your care team know if you think you might be pregnant as this might affect your treatment.   

You might not feel comfortable talking to your care team about sex but it’s important to remember this is their job and they’ve probably had these conversations lots of times before! They should be able to help you with any questions you might have. 

Proton therapy can affect fertility, but it depends on the part of the body that is being treated. You should speak to your consultant or doctor to find out what impact it may have on your fertility. 

You can find out more about how cancer treatment can affect your fertility on our fertility information page.

You will be on your own for scans and treatment but there will be staff nearby most of the time. There will also be staff watching you all the time on monitors and they can speak to you through the intercom. All you need to do is raise your hand to show you want to speak to someone. They will either be behind a glass shield in the room or down a small corridor during your treatment. 

There are currently two proton beam therapy centres in the UK. They are at The Christie in Manchester and University College Hospital in London.

Thank you to the team at The Christie in Manchester for their support with writing this information!