UK ‘failing’ next generation of child cancer patients without more genetic trials

More genetic testing and trials must be rolled out for children if the UK is to avoid failing future generations of young cancer patients, an expert has said.

Authors of a new study believe that targeted treatments, already available for adults in clinical trials, could be even more effective in children because the mutations in their tumours are less complex.

In certain adult cancers, this approach has significantly improved outcomes – but so far children have not benefited.

In a pilot study by London’s Institute of Cancer Research and the Royal Marsden NHS Foundation Trust, around half of 223 children whose tumours were tested were found to have mutations that could be targeted by the drugs.

But only 7% of these were able to access the appropriate treatment, the researchers said.

This was because some patients were already being treated with standard drugs, while others were too ill at the point of being tested.

However, the researchers said there were a “significant” number for whom they felt it was a “shame” that they could not access any other treatment, due to regulatory and funding barriers.

Some of children who received the drugs experienced benefits including their tumours responding, and a stabilisation that prolonged life.

Dr Mike Hubank (pictured), one of the authors, is calling for more trials so that the evidence for how these treatments can affect children can be better understood.

The head of clinical genomics at The Royal Marsden said: “I can sometimes see that the intentions are understandable why children aren’t put onto innovative therapies – there is a fear, there is always a nervousness of doing something wrong. Of course if it’s a child, you don’t know how that drug necessarily works in a child.

“But… if you don’t ever test any of these drugs, you’ll never improve the situation. So are we failing them? We’re failing future generations of children who will get cancer if we don’t start looking for more innovative ways to test children now.

“And that does mean taking a few risks in some circumstances.

“The pharma industry and the regulators are very risk averse, but there’s two kinds of risks.

“There are risks now and there are risks of not doing something in future and I think it’s about getting that balance right, and I don’t think we’ve got that balance right.

“I think we’re too cautious.”

The new test is different from whole genome sequencing because it homes in on a genetic panel of 91 genes that drive and spread cancer’s growth.

The researchers are currently analysing samples from between 5-20 children per week, at a cost of around £350 to the NHS.

They hope that they will be able to test hundreds of children with solid tumours each year.

Study author Dr Sally George, clinical research fellow at The Institute of Cancer Research, London, said making the test more widely available was “a very definite step towards precision medicine in children with cancer”.

She said: “The drivers of childhood tumour are often much clearer, so if we can develop effective drugs for the drivers then the hypothesis is that these types of therapies may actually be more effective in children.”

The study, which involved 20 UK hospitals sending in biopsies, is published in the European Journal of Cancer.

The genetic test was repeated again in children who were given treatment to see what had changed.

They found that in six children, the cancer had acquired new mutations as it evolved in response to treatment.

For 12 children, they tested for the mutations by analysing a blood sample.

The blood tests picked up almost all of the mutations found in the tumour, and in some cases they also found extra mutations not detected in a tumour biopsy.

The researchers hope they will be able to use blood tests to monitor how tumours evolve.

Copyright (c) PA Media Ltd. 2019, All Rights Reserved. Picture (c) The Royal Marsden NHS Foundation Trust.