Children who received radiotherapy which exposed their head are at increased risk of developing a type of brain tumour called a meningioma, new research suggests.
In an analysis of 1011 survivors of childhood cancer published in JAMA Oncology today (Thursday 6th October), researchers led by the investigators at the National Cancer Institute in the US pooled together the largest four previous studies investigating the risk of meningioma after childhood cancer.
The study included 273 survivors of childhood cancer who developed a meningioma, together with 738 survivors who did not develop a meningioma and compared the treatments that they had received for childhood cancer over the period from 1942 to 2000.
Increased exposure of the meninges to radiotherapy led to an increased risk of developing a meningioma and there was a 30-fold increased risk for survivors who had received the highest doses of greater than 24 Gy compared to those not exposed. There was evidence that children whose meninges were exposed under the age of 10 years had a higher risk of meningioma than those exposed at older ages.
There was a suggestion that exposure to a type of chemotherapy called methotrexate may also increase the risk of meningioma, but there was no evidence that the risk increased with increased exposure, so this needs further investigation.
The results support on-going efforts to reduce the exposure of healthy tissue to radiation from cancer treatmentProfessor Michael Hawkins
Professor Michael Hawkins, Director of the Centre for Childhood Cancer Survivor Studies at the University of Birmingham and a co-author of the paper said:
“Childhood cancer is rare, and brain tumours after childhood cancer rarer still, and so we need worldwide pooling of data for satisfactory studies. This pooled case-control analysis provides the largest ever study of meningioma risk among survivors of childhood cancer to the best of our knowledge.
"The results support on-going efforts to reduce the exposure of healthy tissue to radiation from cancer treatment”.
What is a Meningioma?
A Meningioma is a type of brain tumour that begins in the lining of the brain, called the meninges.
Meningiomas are the most common type of primary brain tumour, with 21 out of every 100 brain tumours diagnosed in England between 2006 and 2010.