The effects of breast cancer treatment on cognition

There is growing concern among patients with early-stage breast cancer about self-perceived or objective cognitive changes following their diagnosis and treatment. Symptoms include difficulties with multi-tasking, short-term memory, attention and concentration and word-finding, which may have a detrimental effect on quality of life. The severity of symptoms varies widely, when assessed objectively, the problems are generally subtle. Early clinical observational studies accumulated evidence that suggested cognitive problems could be attributed to the direct neurotoxic effects of chemotherapy. However, observations of cognitive deficits before the start of any treatment question the singular role of chemotherapy. Additionally, results from studies examining the effect of endocrine therapies on cognitive function are mixed. Recent neuroimaging techniques have reported structural and functional neural changes associated with breast cancer treatments. Also, translational research has accumulated evidence for the role of immune dysregulation and neurotoxicity from (pro-) inflammatory cytokines. It is clear that cognitive changes associated with breast cancer and its treatment are still far from being fully understood. Other contributing factors such as surgery, radiotherapy, the psychological burden of having cancer treatment, and treatment-related side effects, in particular fatigue may all play a role. Research into pharmacological and non-pharmacological interventions for cognitive impairment is in preliminary stages. Cognitive impairment following breast cancer diagnosis and treatment remains an important priority in breast cancer survivorship. Further investigations are needed to better understand symptoms and processes involved to enable the development of appropriate support for patients and survivors.