New research presented at Teenage Cancer Trust's International Conference on Teenage and Young Adult Cancer suggests that chemotherapy may affect the memory of young cancer patients.
Previously, research presented at the 2012 meeting of the Radiological Society of North America claimed to have found physiological evidence of "chemo brain" - the "mental fog" commonly described by some cancer patients that affects concentration and memory, post-treatment.
Using positron emission tomography combined with computed tomography, the researchers - from West Virginia University School of Medicine and West Virginia University Hospitals in Morgantown, WV - observed visible changes to brain function following chemotherapy, including significant decreases in regional brain metabolism.
"The study shows that there are specific areas of the brain that use less energy following chemotherapy," the researchers said. "These brain areas are the ones known to be responsible for planning and prioritizing."
'More than half' of chemo patients are in the bottom 10% of cognitive performance
Preliminary results from a new study - conducted by Oana Lindner, a final year PhD student in the School of Psychological Sciences at the University of Manchester in the UK - show decreased performance in cancer patients' cognitive tests in at least the first 5 years after chemotherapy.
Although Lindner has yet to provide further details on the number of patients involved, the university reports that more than half of the participants had scores similar to the bottom 10% of the general population for spatial abilities and a quarter performed in the bottom 10% for long-term verbal memory.
"This means that many 16 to 50 year old cancer patients may have difficulties in learning and memory," Lindner explains. "It certainly seems to support the phenomenon of chemo brain that so many cancer patients experience."
Lindner and colleagues are now working on additional analyses for factors such as depression or tiredness: "Apart from studying the underlying mechanisms of these impairments, future analyses will also be aimed at finding out how long lasting these effects are."
The study is the first in the UK to investigate how memory and attention performance are affected by chemotherapy across several different cancer groups - breast cancer, lymphoma, sarcoma and germ cell tumor.
Nigel Revell, director of education and advocacy at Teenage Cancer Trust, says that the results confirm what cancer experts have long suspected, that "chemotherapy can impact young people who have gone through the treatment process and have returned back to their studies but are finding it harder to adapt, due to memory loss and lack of concentration span."
Revell explains that the research is relevant to Teenage Cancer Trust as it is the only UK charity dedicated to improving the quality of life of young people with cancer aged 13-24.
"Given the increasing number of people living with and beyond cancer, this is particularly pertinent," he says, explaining that of the young people the trust works with, "most of them are still in education and want to continue down this path once their chemotherapy is over."
One of these young people is 17-year-old Lily Anderson, a former Teenage Cancer Trust patient who describes her experience of attempting to study following her cancer treatment:
"It felt like my brain had become exhausted and more difficult to use. My head was always fuzzy, and my memory and concentration were awful. I couldn't focus on anything for more than half an hour and trying to learn new things was very difficult. It made it almost impossible for me to continue with my school work.
When I was younger, pre-cancer, I was an A/A* student, and picked up things very easily. I breezed through SATS and loved challenging myself. It was difficult going from having such a bright, alive mind to having one that's sluggish and disconnected."