Chemotherapy could cause brain damage in breast cancer patients scientists have warned.
A groundbreaking study discovered that breast cancer patients who had undergone the treatment – which uses medicine to kill cancerous cells – had significantly less activity in parts of the brain responsible for memory and planning compared to those who were not treated.
Researchers from Stanford University believe the findings could explain the phenomenon ‘chemo brain’ – a term used to describe foggy thinking and memory lapses following chemotherapy sessions.
Lead author Shelli Kesler said: ‘This is a huge validation for these women who are telling their doctors ‘something is wrong with me.”
The study involved 25 breast cancer patients who had been treated with chemotherapy, 19 breast cancer patients who had surgery and other treatments, and 18 healthy women.
All were asked to perform a card-sorting task, involving problem-solving skills while their brain activity was monitored through functional magnetic resonance imaging (fMRI).
Each participant was also asked to complete a questionnaire assessing their own cognitive abilities.
The 25 patients who had been treated with chemotherapy, made more errors on the task and the scans revealed reduced activity in parts of the brain responsible for working memory, cognitive control, monitoring and planning.
Kesler added: ‘This shows that when a patient reports she’s struggling with these types of problems, there’s a good chance there has been a brain change.’
The study, published in the Archives of Neurology supports previous findings, and cancer patients have long complained of neurological side effects such as short-term memory loss and, in extreme cases, vision loss, and even dementia following chemotherapy.
But doctors have traditionally dismissed these complaints attributing them to stress caused by cancer diagnosis and treatment.
Kesler said that the next step is to start investigating which patients are most vulnerable to these types of deficits caused by chemotherapy administered either in tablet form, or via an injection or infusion directly into a vein.
A 2008 study by the University of Rochester Medical Center (URMC) and Harvard Medical School linked the widely used chemotherapy drug 5-fluorouracil (5-FU) to the deterioration of healthy brain cells.
Lead author Mark Noble said: ‘It is clear that, in some patients, chemotherapy appears to trigger a degenerative condition in the central nervous system.’
‘It is critical that we understand their precise impact on the central nervous system, and then use this knowledge as the basis for discovering means of preventing such side effects.’