Around 1 in 5 people diagnosed with cancer in the UK take part in a clinical trial.
A trial looking at treatment for children and teenagers with a primitive neuroectodermal tumour that has come back (PNET-CNS 2000 01)
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This trial looked at using high dose chemotherapy and a stem cell transplant for children who had a neuroectodermal tumour that had come back following treatment.
Primitive neuroectodermal tumour (PNET) is a group of brain cancers that mainly occur in children. Doctors treat PNETs in the brain with surgery, radiotherapy and chemotherapy. But sometimes these treatments don’t work very well and the cancer comes back.
This trial was for children and young people up to the age of 21. We use the term 'you' in this summary, but of course if you are a parent, we are referring to your child.
If you have a PNET in the brain that has come back, it is difficult to treat.
The researchers wanted to find out if
Summary of results
The trial team found that high dose chemotherapy was of little benefit for children and young people with primitive neuroectodermal tumours (PNETs) in the brain that had come back.
This trial included 45 children and young people who had a PNET that had come back. Of these, 40 had the most common type of PNET called a medulloblastoma and 5 had a rarer type called a supratentorial PNET. Most of them had previously had radiotherapy.
In this study, the planned treatment was cyclophosphamide and surgery or radiotherapy if appropriate. If this got rid of all or most of the cancer (put it into complete or nearly complete remission), the children and young people taking part could go on to have high dose chemotherapy.
Of the 5 children who had supratentorial PNET
- All 5 started cyclophosphamide chemotherapy
- 4 had surgery before having cyclophosphamide
- 1 went on to have high dose chemotherapy and radiotherapy
Unfortunately all of their tumours continued to grow and sadly they died.
Of the 40 children with medulloblastoma
- All had cyclophosphamide
- 19 also had surgery
- 22 went on to have high dose chemotherapy
The researchers found that the average length of time they lived was just over 1 and half years.
After an average follow up period of nearly 7 and half years, 37 children had sadly died. The trial team concluded there was little benefit in giving high dose chemotherapy to children whose primitive neuroectodermal tumour had come back.
We have based this summary on information from the team who ran the trial. The information they sent us has been reviewed by independent specialists (
How to join a clinical trial
Professor Barry Pizer
Children's Cancer and Leukaemia Group (CCLG)
Chugai Pharma UK Ltd
National Institute for Health Research Cancer Research Network (NCRN)