Researchers from the Netherlands caution that exposing the human brain to radiotherapy, a practice that is widespread in treatments against brain tumors known as low-grade glioma, can actually be very dangerous in the long run. The investigation revealed that patients who were treated using this method showed a far greater risk of suffering from memory and attention deficits 12 years after they had the procedure than people treated without radiotherapy. In a new study published in the journal The Lancet Neurology, the Dutch team advises physicians to hold off on using radiotherapy whenever possible, so as to avoid such side effects.

In the case of low-grade glioma, radiotherapy is given to patients so as to prevent the relapsing of cancer. But, at this point, there is some debate among professionals as to whether this therapy should be administered immediately after the initial surgery, or if physicians should not prescribe it until signs of relapse occur. Scientists have cautioned for a long time that radiotherapy also acts on healthy parts of the brain, causing mild damage to the healthy tissue around tumors. This knowledge was what prompted the researchers to undertake this study.

Another previous study, conducted on the same 65 patients as the new one, revealed that 6 years after radiotherapy the patients showed no clear signs of any impairment in terms of attention, memory, and their ability to respond to stimuli. It would appear, the experts say, that it takes a lot more time for the symptoms to develop than originally thought. Statistical correlations revealed that only 27 percent of the patients who only had surgery showed mental decline, whereas more than 57 percent of those who had received radiotherapy showed symptoms, the BBC News informs.

“It always depends on the patient, but if it is possible to defer radiotherapy, maybe people should,” advises the leader of the new study, Dr Linda Douw. She is an expert at the VU University Medical Center Department of Neurology, in Amsterdam. The scientist also reveals that numerous other therapies such as chemo are currently under scrutiny, to assess their long-term effects on the human body.

“Surgery is generally a preferred option with chemotherapy or radiotherapy coming into play at a later stage, if the glioma progresses. Continued research and increased knowledge about the disease is enabling us to treat it increasingly effectively while reducing side effects,” concludes Cancer Research UK scientist Dr Jeremy Rees, who also holds an appointment at the National Hospital for Neurology and Neurosurgery Honorary.