Research claims "safe" doses of radiotherapy may contribute to progressive mental decline in brain cancer patients.
According to a study published in the journal The Lancet Neurology, radiotherapy used to treat the most common form of brain tumour, low-grade glioma, has been associated with mental impairment over a period of six years. Questions remain over the effect of radiotherapy on long-term brain tumour survivors.
The latest study led by Linda Douw, from the VU University Medical Centre in Amsterdam, the Netherlands, looked at 65 patients an average of 12 years after treatment.
Tests on attention, executive functioning, verbal memory, working memory, psychomotor functioning and information processing speed were carried out and researchers found more than half the patients who were given radiotherapy had suffered a mental decline compared with 27% of those who were not.
Radiotherapy patients were found to have poorer attentional and executive functioning, and were slower at information processing.
The team concluded that "The current results indicate that radiotherapy is associated with long-term cognitive deterioration, regardless of fraction dose" and that all patients who had radiotherapy were at risk, not just those given high-level doses of radiation.