Radiation is a risk factor for a type of brain tumour in people under age 30, scientists, including one of Indian-origin, have found.
Researchers analysed records of 35 patients who before the age of 30 were diagnosed with meningiomas. Meningiomas are usually benign tumours that arise from the meninges — the membranes that surround the brain and spinal cord.
Five of the patients had been exposed to ionising radiation earlier in their lives.
This included two patients who received radiation for leukemia at ages 5 and 6; one who received radiation at age 3 for a brain tumour known as a medulloblastoma; and one who received radiation for an earlier skull base tumour that appeared to be a meningioma.
The fifth patient had been exposed at age 9 to radiation from the Chernobyl nuclear power plant disaster in Ukraine. Twenty years later, he was diagnosed with a meningioma.
In the five patients, the average latency period for the tumours was 23.5 years, according to the study published in the journal Neuroscience Discovery.
“The results of this preliminary study have prompted us to look closely at radiation’s effects on the brain,” said Vikram Prabhu, a neurosurgeon at Loyola University Hospital, and first author of the study.
Meningiomas comprise about one-third of all primary brain tumours, but are rare in children and young adults.
Prabhu and his team are doing a follow-up study on patients of all ages who have been treated at Loyola for meningiomas.
In collaboration with Dr Omer Iqbal, from the Department of Pathology, they are analysing the genetics and biology of tumour samples to find how they differ from samples of tumours not linked to radiation.
“It is important to compare and contrast these post-radiation meningiomas with de novo meningiomas, both clinically and biologically, in order to further define optimal therapy,” said Loyola oncologist Kevin Barton, a co-author of the study.
Researchers so far have identified 14 meningioma patients who were exposed to radiation earlier in their lives.
These include three patients who were exposed to Chernobyl radiation and 11 patients who received therapeutic radiation for such conditions as leukemia, medulloblastoma tumours and fungal infections of the scalp.
“Although we have identified radiation as a risk factor for meningiomas, radiation remains an important part of the treatment regimen for certain lesions, and is helping us obtain good results for our patients,” said Dr Edward Melian, a radiation oncologist at Loyola and co-author of the study.
People who have been exposed to large doses of radiation to the head face a small risk of later developing brain tumours.
If such a person experiences symptoms associated with brain tumours, including headaches, seizures, vomiting and blurry vision, he or she should see a doctor, Prabhu said.