Cognitive function after chemotherapy in adults with solid tumours

BackgroundEvidence is emerging that some cancer survivors suffer cognitive impairment after chemotherapy; the cause is unknown.MethodsHere we review studies evaluating cognitive impairment in adult cancer survivors and discuss methodological challenges associated with this research. We evaluate evidence for cognitive impairment in cancer patients, the incidence of self-reported impairment, and identify potential mechanisms and confounders.ResultsMost studies of cognitive function are cross-sectional and report impairment in 15–45% of subjects. Longitudinal studies suggest that some impairment is present prior to receiving chemotherapy, and that this worsens in some patients. The aetiology is unknown. A larger number of subjects self-report changes in cognitive function after chemotherapy; this does not correlate with objective testing.ConclusionsCognitive impairment occurs in a subset of cancer survivors and is generally subtle. Most evidence suggests an association with chemotherapy although other factors associated with the diagnosis and treatment of cancer may contribute.