The Relationship between Cancer and Dementia: An Updated Review

SIMPLE SUMMARY: As cancer treatments continue to improve, more patients are surviving cancer. However, treatment-related complications, such as cognitive impairment, are becoming increasingly prevalent. Recent research suggests a link between cancer and dementia. Progress has been made in understanding the cognitive changes associated with cancer treatment, but more needs to be carried out to prevent and screen early for dementia in cancer survivors. In this review, we summarize the current literature on the incidence and mechanisms of cognitive impairment in patients with various types of cancer, including lung, breast, head and neck, gastric, prostate, colorectal, and brain tumors/metastases following different treatments. We also discuss potential risk factors and cellular mechanisms of neurodegeneration caused by cancer treatment in order to identify the early onset of cognitive deficits in cancer patients. ABSTRACT: The risk of cancer and dementia increases with age, raising complex questions about whether it is appropriate to continue cancer treatment in older patients. There is emerging research suggesting the association between cancer and dementia. However, the mechanistic underpinnings are still under investigation. Progress has already been made toward understanding the cognitive effects associated with cancer therapy. Such associations raise awareness about the need to establish better prevention methods and early screening in clinical practice. Additionally, recent studies have suggested possible therapeutic strategies for better preserving cognitive function and reducing the risk for dementia before patients start cancer treatment. We review the current literature and summarize the incidence and mechanisms of cognitive impairment in patients with lung cancer, breast cancer, head and neck cancer, gastric cancer, prostate cancer, colorectal cancer, and brain tumor/brain metastasis following different kinds of therapies. Possible risk factors are suggested to identify the early onset of cognitive changes in cancer patients and provide more insight into the pathophysiological process of dementia.