Boost for cancer therapy sought by Ashya King's family

Health 1 September 2014
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Ashya King’s family say they took him to Spain for treatment

(Image: Rex)

A police hunt was launched last week after the parents of a child with a type of brain cancer called medulloblastoma removed him from Southampton General Hospital and fled to Spain.

The brother of Ashya King said yesterday that his family took the 5-year-old so that they could seek a form of cancer treatment called proton beam therapy that they couldn’t get on the National Health Service (NHS).

What is proton beam therapy?
It is a precise form of radiotherapy used to treat a number of rare and difficult-to-reach cancers.


Conventional forms of radiotherapy use X-rays to kill cancer cells, but these are a blunt tool. X-rays carry energy in the form of an electromagnetic wave. As they pass through the body, X-rays damage tumour cells and healthy cells in their path until all their energy has been dissipated.

A newer approach is to use beams of energetic protons. These act in much the same way as X-ray therapy but are less damaging because the protons stop moving once they have hit their target. ” A proton beam goes into the patient, gets to the end of its range, and then deposits all its energy,” says Philip Mayles, head of physics at the Clatterbridge Cancer Centre in Wirral, the only proton beam treatment facility in the UK.

The centre, which is run by the NHS, has been using proton therapy for more than two decades, but only for eye tumours. Mayles estimates it is used on about 150 patients a year.

When else is proton beam therapy used?
Because of its high precision, proton beam therapy is suited to hard-to-reach cancers, such as brain or spine tumours that have yet to spread elsewhere. It is widely used in the US for prostate cancer but the technique is not without its hazards. “You have to get the range of the beam exactly right, otherwise you could miss the back of the tumour, or give a large dose to something beyond it,” says Mayles.

In countries where it is offered, proton beam therapy is often used for treating childhood cancers. Children with brain tumours are especially affected by the damaging side-effects of the more conventional radiotherapies, because their developing tissues are more susceptible to radiation damage. “If you’re going to irradiate a child, you want to get the radiation very precisely to the bit that you’re wanting to treat,” says Mayles.

That’s because one of the downsides of radiotherapy is that it can induce other cancers years later. “If you’re 65, the fact that you get an induced cancer 15 years later is almost irrelevant, whereas if you’re 16 or 5, then you’ve got your whole life for that to be expressed,” says Mayles.

Why is the treatment not offered more widely in the UK?
It is expensive to build the facilities and expensive to use – it could cost £40,000 for a course of treatment.

What’s more, because most proton facilities are in the US, it has been difficult to conduct clinical trials on the therapy because of how the US healthcare system works. Mayles says that because people in US pay for their treatment, patients get to decide what type they would like, so they are unlikely to opt for a randomised clinical trial where they might be given a conventional X-ray treatment rather than the proton therapy they want. Therefore, the UK has been slow to endorse the treatment. There are still questions about how effective it is, and whether it is better than the cheaper, more conventional treatments available here.

How can people in the UK access the treatment?
People can be sent to one of two centres in Florida and Oklahoma, at a cost to the NHS of about £100,000, if a panel of doctors decides that is the best course of action.

When will it be available on the NHS in this country?
It should be available by the end of the decade. The government has committed to funding two proton beam therapy centres, in London and Manchester, at a combined cost of £250 million. The centres are due to open in 2018, and are expected to treat about 1,500 patients a year.

While these cutting-edge centres will be used to address the unanswered questions about the effectiveness of the approach, on their blog Cancer Research UK points out that they will be of no use to the vast majority of the country’s cancer patients. It is thought that only about 1 per cent of cancer patients might be suitable candidates for proton beam therapy – mostly children with brain tumours. The NHS is not planning to offer the therapy for prostate cancer.

Article amended on 3 September 2014

When this article was first published, it said that a randomised clinical trial would use a "sham" treatment as a control. This has now been corrected.

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