The association between endocrine therapy use and dementia among post-menopausal women treated for early-stage breast cancer in Ontario, Canada

Breast cancer therapies reduce risk of Alzheimer's disease and promote estrogenic pathways and action in brain

Worldwide, an ever-increasing number of women are prescribed estrogen-modulating therapies (EMTs) for the treatment of breast cancer. In parallel, aging of the global population of women will contribute to risk of both breast cancer and Alzheimer's disease. To address the impact of anti-estrogen therapies on risk of Alzheimer's and neural function, we conducted medical informatic and molecular pharmacology analyses to determine the impact of EMTs on risk of Alzheimer's followed by determination of EMT estrogenic mechanisms of action in neurons. Collectively, these data provide both clinical and mechanistic data indicating that select EMTs exert estrogenic agonist action in neural tissue that are associated with reduced risk of Alzheimer's disease while simultaneously acting as effective estrogen receptor antagonists in breast.

Neurologic complications of breast cancer

Breast cancer is a heterogeneous disease with unique neurologic complications that can arise from central nervous system (CNS) involvement or secondary to treatments themselves. As progress is made, with more targeted therapies and combinations available, particularly in the realm of human epidermal growth factor receptor 2 (HER2)-positive disease, the role of these new agents in patients with CNS disease is gradually evolving, although intracranial efficacy itself is lagging. At the same time, both systemic and local standard therapies pose clinical challenges regarding neurologic complications, such as peripheral neuropathy and cognitive changes. The development of new agents, such as immunotherapy, and new strategies, such as incorporating systemic therapies into local therapy, unveil new presentations of neurological complications.

A Systematic Review on the Potential Acceleration of Neurocognitive Aging in Older Cancer Survivors

As survival rates increase, more emphasis has gone to possible cognitive sequelae in older cancer patients, which could be explained by accelerated brain aging. In this review, we provide a complete overview of studies investigating neuroimaging, neurocognitive, and neurodegenerative disorders in older cancer survivors (>65 years), based on three databases (Pubmed, Web of Science and Medline). Ninety-six studies were included. Evidence was found for functional and structural brain changes (frontal regions, basal ganglia, gray and white matter), compared to healthy controls. Cognitive decline was mainly found in memory functioning. Anti-hormonal treatments were repeatedly associated with cognitive decline (tamoxifen) and sometimes with an increased risk of Alzheimer's disease (androgen deprivation therapy). Chemotherapy was inconsistently associated with later development of cognitive changes or dementia. Radiotherapy was not associated with cognition in patients with non-central nervous system cancer but can play a role in patients with central nervous system cancer, while neurosurgery seemed to improve their cognition in the short-term. Individual risk factors included cancer subtypes (e.g., brain cancer, hormone-related cancers), treatment (e.g., anti-hormonal therapy, chemotherapy, cranial radiation), genetic predisposition (e.g., APOE, COMT, BDNF), age, comorbidities (e.g., frailty, cognitive reserve), and psychological (e.g., depression, (post-traumatic) distress, sleep, fatigue) and social factors (e.g., loneliness, limited caregiver support, low SES). More research on accelerated aging is required to guide intervention studies.

The Relationship between Cancer and Dementia: An Updated Review

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.

[Why and how to assess older people with cancer?]

The older population accounts for almost 60% of new cancers. Their management is a public health problem and is complex. It raises different questions: Is the patient's prognosis linked to cancer or another pathology? The heterogeneity of this population emphasises the importance of the overall condition assessment, in particular to avoid over-treatment (or under-treatment), and to be able to identify frail or vulnerable elderly patients who are at risk of having more treatment toxicities. Through this article, we will recall the importance of geriatric in-depth evaluation (EGA) by detailing the different factors that impact the therapeutic decision, tolerance to treatments… This EGA is however time-consuming and not all patients can be evaluated. In order to identify the subjects covered by this EGA, screening scales have been developed. Finally, we will develop the place of research in oncogeriatric management.