An increased number of inflammatory cells in the brain correlates with cognitive complaints in cancer patients after their treatment, according to new research by KU Leuven PhD student Gwen Schroyen.
It had long been known that some cancer patients can struggle with cognitive complaints after their treatment, even after they have been declared cured. Some people experience difficulty coming up with certain words, find it harder to multitask or lose their thread when briefly interrupted during a conversation.
The researchers tried to find an explanation for the phenomenon of an inflammatory reaction in the brain, as such a reaction is known to be present in the rest of the body, with cancer and during treatment. Other studies also indicated those elevated levels in the brains of rats or mice when a tumour was present or during cancer treatment.
Schroyen's team was able to set up such a study in humans for the first time and the increased amount of inflammatory cells could be clearly visualised in the brains of treated cancer patients.
What they found
Thirty breast cancer patients, 15 of whom had finished their chemotherapy a month ago and 15 of whom had not received chemotherapy, were tested. A control group of 15 people who had never had breast or any other cancer, were included in the study.
The brains of each person were monitored via scans and cognitive tests were taken. Those who had received chemotherapy showed a markedly increased concentration of inflammatory cells in certain areas of the brain.
Moreover, patients who scored worse on cognitive tests also had an increased inflammatory response in the frontal lobe of the brain, the place where people's higher cognitive functions and personality traits are expressed, among other things.
"The discovery is extremely valuable," Schroyen said. "For a long time it was thought that patients' complaints 'were only in their heads' and that there was nothing structurally wrong."