Cognition in breast cancer survivors: hormones versus depression

Functional network disorganization and cognitive decline following fractionated whole-brain radiation in mice

Cognitive dysfunction following radiotherapy (RT) is one of the most common complications associated with RT delivered to the brain, but the precise mechanisms behind this dysfunction are not well understood, and to date, there are no preventative measures or effective treatments. To improve patient outcomes, a better understanding of the effects of radiation on the brain's functional systems is required. Functional magnetic resonance imaging (fMRI) has shown promise in this regard, however, compared to neural activity, hemodynamic measures of brain function are slow and indirect. Understanding how RT acutely and chronically affects functional brain organization requires more direct examination of temporally evolving neural dynamics as they relate to cerebral hemodynamics for bridging with human studies. In order to adequately study the underlying mechanisms of RT-induced cognitive dysfunction, the development of clinically mimetic RT protocols in animal models is needed. To address these challenges, we developed a fractionated whole-brain RT protocol (3Gy/day for 10 days) and applied longitudinal wide field optical imaging (WFOI) of neural and hemodynamic brain activity at 1, 2, and 3 months post RT. At each time point, mice were subject to repeated behavioral testing across a variety of sensorimotor and cognitive domains. Disruptions in cortical neuronal and hemodynamic activity observed 1 month post RT were significantly worsened by 3 months. While broad changes were observed in functional brain organization post RT, brain regions most impacted by RT occurred within those overlapping with the mouse default mode network and other association areas similar to prior reports in human subjects. Further, significant cognitive deficits were observed following tests of novel object investigation and responses to auditory and contextual cues after fear conditioning. Our results fill a much-needed gap in understanding the effects of whole-brain RT on systems level brain organization and how RT affects neuronal versus hemodynamic signaling in the cortex. Having established a clinically-relevant injury model, future studies can examine therapeutic interventions designed to reduce neuroinflammation-based injury following RT. Given the overlap of sequelae that occur following RT with and without chemotherapy, these tools can also be easily incorporated to examine chemotherapy-related cognitive impairment.

Cancer-related cognitive impairment in racial and ethnic minority groups: a scoping review

PURPOSE

Disparities in cognitive function among racial and ethnic groups have been reported in non-cancer conditions, but cancer-related cognitive impairment (CRCI) in racial and ethnic minority groups is poorly understood. We aimed to synthesize and characterize the available literature about CRCI in racial and ethnic minority populations.

METHODS

We conducted a scoping review in the PubMed, PsycInfo, and Cumulative Index to Nursing and Allied Health Literature databases. Articles were included if they were published in English or Spanish, reported cognitive functioning in adults diagnosed with cancer, and characterized the race or ethnicity of the participants. Literature reviews, commentaries, letters to the editor, and gray literature were excluded.

RESULTS

Seventy-four articles met the inclusion criteria, but only 33.8% differentiated the CRCI findings by racial or ethnic subgroups. There were associations between cognitive outcomes and the participants' race or ethnicity. Additionally, some studies found that Black and non-white individuals with cancer were more likely to experience CRCI than their white counterparts. Biological, sociocultural, and instrumentation factors were associated with CRCI differences between racial and ethnic groups.

CONCLUSIONS

Our findings indicate that racial and ethnic minoritized individuals  may be disparately affected by CRCI. Future research should use standardized guidelines for measuring and reporting the self-identified racial and ethnic composition of the sample; differentiate CRCI findings by racial and ethnic subgroups; consider the influence of structural racism in health outcomes; and develop strategies to promote the participation of members of racial and ethnic minority groups.

Depression, Inflammation, and Intestinal Permeability: Associations with Subjective and Objective Cognitive Functioning throughout Breast Cancer Survivorship

About one-in-three breast cancer survivors have lingering cognitive complaints and objective cognitive impairment. Chronic inflammation and intestinal permeability (i.e., leaky gut), two risk factors for cognitive decline, can also fuel depression-another vulnerability for cognitive decline. The current study tested whether depression accompanied by high levels of inflammation or intestinal permeability predicted lower subjective and objective cognitive function in breast cancer survivors. We combined data from four breast cancer survivor studies (n = 613); some had repeated measurements for a total of 1015 study visits. All participants had a blood draw to obtain baseline measures of lipopolysaccharide binding protein-a measure of intestinal permeability, as well as three inflammatory markers that were incorporated into an inflammatory index: C-reactive protein, interleukin-6, and tumor necrosis factor-α. They reported depressive symptoms on the Center for Epidemiological Studies depression scale (CES-D), and a binary variable indicated clinically significant depressive symptoms (CES-D ≥ 16). The Kohli (749 observations) and the Breast Cancer Prevention Trial (591 observations) scales assessed subjective cognitive function. Objective cognitive function tests included the trail-making test, Hopkins verbal learning test, Conners continuous performance test, n-back test, FAS test, and animal-naming test (239-246 observations). Adjusting for education, age, BMI, cancer treatment type, time since treatment, study visit, and fatigue, women who had clinically elevated depressive symptoms accompanied by heightened inflammation or intestinal permeability reported poorer focus and marginally poorer memory. However, poorer performance across objective cognitive measures was not specific to inflammation-associated depression. Rather, there was some evidence of lower verbal fluency; poorer attention, verbal learning and memory, and working memory; and difficulties with visuospatial search among depressed survivors, regardless of inflammation. By themselves, inflammation and intestinal permeability less consistently predicted subjective or objective cognitive function. Breast cancer survivors with clinically significant depressive symptoms accompanied by either elevated inflammation or intestinal permeability may perceive greater cognitive difficulty, even though depression-related objective cognitive deficits may not be specific to inflammation- or leaky-gut-associated depression.

Long-Term Cognitive Dysfunction in Cancer Survivors

Cancer-related cognitive impairment (CRCI) is a frequent side effect experienced by an increasing number of cancer survivors with a significant impact on their quality of life. Different definitions and means of evaluation have been used in available literature; hence the exact incidence of CRCI remains unknown. CRCI can be described as cognitive symptoms reported by cancer patients in self-reported questionnaires or as cognitive changes evaluated by formal neuropsychological tests. Nevertheless, association between cognitive symptoms and objectively assessed cognitive changes is relatively weak or absent. Studies have focused especially on breast cancer patients, but CRCI has been reported in multiple types of cancer, including colorectal, lung, ovarian, prostate, testicular cancer and hematological malignancies. While CRCI has been associated with various treatment modalities, including radiotherapy, chemotherapy, hormone therapy and novel systemic therapies, it has been also detected prior to cancer treatment. Therefore, the effects of cancer itself with or without the psychological distress may be involved in the pathogenesis of CRCI as a result of altered coping mechanisms after cancer diagnosis. The development of CRCI is probably multifactorial and the exact mechanisms are currently not completely understood. Possible risk factors include administered treatment, genetic predisposition, age and psychological factors such as anxiety, depression or fatigue. Multiple mechanisms are suggested to be responsible for CRCI, including direct neurotoxic injury of systemic treatment and radiation while other indirect contributing mechanisms are hypothesized. Chronic neuroinflammation mediated by active innate immune system, DNA-damage or endothelial dysfunction is hypothesized to be a central mechanism of CRCI pathogenesis. There is increasing evidence of potential plasma (e.g., damage associated molecular patterns, inflammatory components, circulating microRNAs, exosomes, short-chain fatty acids, and others), cerebrospinal fluid and radiological biomarkers of cognitive dysfunction in cancer patients. Discovery of biomarkers of cognitive impairment is crucial for early identification of cancer patients at increased risk for the development of CRCI or development of treatment strategies to lower the burden of CRCI on long-term quality of life. This review summarizes current literature on CRCI with a focus on long-term effects of different cancer treatments, possible risk factors, mechanisms and promising biomarkers.

A randomised wait-list controlled trial to evaluate Emotional Freedom Techniques for self-reported cancer-related cognitive impairment in cancer survivors (EMOTICON)

BACKGROUND

Cancer-related cognitive impairment (CRCI) is a prevalent source of comprised quality of life in cancer survivors. This study evaluated the efficacy of Emotional Freedom Techniques (EFT) on self-reported CRCI (sr-CRCI).

METHODS

In this prospective multicentre randomised wait-list controlled study (ClinicalTrials.gov Identifier: NCT02771028), eligible cancer survivors had completed curative treatment, were 18 years or older and screened positive for sr-CRCI with ≥ 43 on the Cognitive Failures Questionnaire (CFQ). Participants were randomised to the immediate treatment group (ITG) or wait-list control (WLC) group, based on age (< or ≥ 65 years), gender, treatment (chemotherapy or not), and centre. The ITG started to apply EFT after inclusion and performed this for 16 weeks. The WLC group could only start the application of EFT after 8 weeks of waiting. Evaluations took place at baseline (T0), 8 weeks (T1) and 16 weeks (T2). The primary outcome was the proportion of patients with sr-CRCI according to the CFQ score.

FINDINGS

Between October 2016 and March 2020, 121 patients were recruited with CFQ ≥ 43 indicating sr-CRCI. At T1, the number of patients scoring positive on the CFQ was significantly reduced in the ITG compared to the WLC group (40.8% vs. 87.3% respectively; p<0.01). For the WLC group, a reduction in CFQ scores was observed at T2, comparable to the effect of the ITG at T1. Linear mixed model analyses indicated a statistically significant reduction in the CFQ score, distress, depressive symptoms, fatigue and also an improvement in quality of life.

INTERPRETATION

This study provides evidence for the application of EFT for sr-CRCI in cancer survivors and suggests that EFT may be useful for other symptoms in cancer survivors.

Psychological Aspects to Consider in Breast Cancer Diagnosis and Treatment

PURPOSE OF REVIEW

Breast cancer (BC) is the most common cancer diagnosed in women in the West World. Coping with cancer is cause of extreme stress for patients and their family. The purpose of this review is to evaluate possible approaches to follow to control those situations that can impact on quality of life (QoL) and compliance to treatments.

RECENT FINDINGS

Anxiety, distress, depression, and posttraumatic stress disorder are the most frequent psychological disorders in BC patients. Cognitive disorders and sexual dysfunction can also be important in affecting QoL both in younger and older patients. Younger and older patients show different characteristics of these disorders and different strategies of managing them. Several psychotherapeutic and supportive approaches have proven effective in managing psychological disorders in BC patients. Every BC patient should be supported with these techniques during her entire oncological history, in order to increase QoL and compliance to treatments.

Utility of the Patient-Reported Outcomes Measurement Information System (PROMIS) to measure primary health outcomes in cancer patients: a systematic review

OBJECTIVE

To systematically review the literature on how the Patient-Reported Outcomes Measurement Information System (PROMIS) measure system is used to assess patient-reported outcomes (PROs) in cancer patients.

METHODS

We conducted a systematic review following the PRISMA guidelines. Articles were identified through searches of PubMed, EMBASE, and additional manual review of the publications listed on the PROMIS website. We included studies measuring outcomes, including physical function, fatigue, pain, anxiety, and depression in cancer patients. Eligible articles included interventional and observational studies published in English between 2009 and 2019.

RESULTS

A total of 1789 records were identified and screened by three reviewers, 118 articles were reviewed in full text, and 42 articles met the inclusion criteria. The majority of studies used the PROMIS measure system to prospectively assess longitudinal changes in PROs; the number of measurements ranges from 2 to 4 with the time points of follow-up set at 3, 6, and 12 months after the baseline assessment. Depression and fatigue were the most frequently measured outcomes. Fixed-length short forms with four items were the most common measure types. A transition toward utilizing a web- or smartphone-based electronic tool was observed to limit the burden of the conventional paper-based survey to collect and store PROs.

CONCLUSION

The PROMIS measure system is increasingly popular to measure PROs in cancer patients with acceptance of its various short forms and electronic-based systems to administer data electronically. Findings from this review highlight various aspects of PROMIS and may help health professionals in their choice of PRO tools for optimizing care and support for cancer patients.

Cancer-related cognitive impairment: an update on state of the art, detection, and management strategies in cancer survivors

BACKGROUND

Advances in diagnostic and therapeutic strategies in oncology have significantly increased the chance of survival of cancer patients, even those with metastatic disease. However, cancer-related cognitive impairment (CRCI) is frequently reported in patients treated for non-central nervous system cancers, particularly during and after chemotherapy.

DESIGN

This review provides an update of the state of the art based on PubMed searches between 2012 and March 2019 on 'cognition', 'cancer', 'antineoplastic agents' or 'chemotherapy'. It includes the most recent clinical, imaging and pre-clinical data and reports management strategies of CRCI.

RESULTS

Evidence obtained primarily from studies on breast cancer patients highlight memory, processing speed, attention and executive functions as the most cognitive domains impaired post-chemotherapy. Recent investigations established that other cancer treatments, such as hormone therapies and targeted therapies, can also induce cognitive deficits. Knowledge regarding predisposing factors, biological markers or brain functions associated with CRCI has improved. Factors such as age and genetic polymorphisms of apolipoprotein E, catechol-O-methyltransferase and BDNF may predispose individuals to a higher risk of cognitive impairment. Poor performance on neuropsychological tests were associated with volume reduction in grey matter, less connectivity and activation after chemotherapy. In animals, hippocampus-based memory and executive functions, mediated by the frontal lobes, were shown to be particularly susceptible to the effects of chemotherapy. It involves altered neurogenesis, mitochondrial dysfunction or brain cytokine response. An important next step is to identify strategies for managing cognitive difficulties, with primary studies to assess cognitive training and physical exercise regimens.

CONCLUSIONS

CRCI is not limited to chemotherapy. A multidisciplinary approach has improved our knowledge of the complex mechanisms involved. Nowadays, studies evaluating cognitive rehabilitation programmes are encouraged to help patients cope with cognitive difficulties and improve quality of life during and after cancer.

Long-Term Fatigue and Cognitive Disorders in Breast Cancer Survivors

Survivors of early-stage breast cancer may report treatment-related side effects that persist for several years after the end of primary treatment. Among these, fatigue and cognitive disorders are frequent complaints and can negatively impact quality of life. Cancer-related fatigue is a very prevalent and distressing long-term side effect among breast cancer survivors that typically improves after completion of treatment, although many patients report severe fatigue several years post-treatment. Cognitive disorders are also common among survivors of breast cancer, especially if treated with chemotherapy. These symptoms are usually mild-to-moderate and often transient. Cognitive recovery is frequently observed within months or a few years after completion of chemotherapy or endocrine therapy. However, some breast cancer survivors may have persistent cognitive difficulties. Several types of interventions have proved to be beneficial in reducing cancer-related fatigue and cognitive difficulties. Most of these interventions for cancer-related fatigue are thought to be effective by reducing inflammation or disrupting pro-inflammatory circuits. Further studies are needed on cognitive management that has showed promising results. This narrative review summarizes the state of the art regarding long-term fatigue and cognitive disorders in patients with early breast cancer, describing prevalence, impact, pathophysiology, and risk factors, and focusing on available interventions.

Age-dependent brain volume and neuropsychological changes after chemotherapy in breast cancer patients

This study investigated volumetric brain changes and cognitive performance in premenopausal and postmenopausal patients treated for early-stage breast cancer. Participants underwent elaborate neurocognitive assessments (neuropsychological testing, cognitive failure questionnaire, and high-resolution T1-weighted structural MRI) before and after chemotherapy. Volumetric brain changes were estimated, using longitudinal deformation-based morphometry, and correlated with cognitive changes. In total, 180 women participated in this study, of whom 72 patients with breast cancer had received adjuvant chemotherapy (C+), 49 patients did not receive chemotherapy (C-), and 59 healthy controls (HC). The population was categorized into two age groups: A young group who were premenopausal and younger than 52 years at baseline (n = 55C+/32C-/41HC), and an older group who were postmenopausal and older than 60 years (n = 17C+/17C-/18HC). Cognitive impairment occurred after chemotherapy in both young and older patients, although older patients showed more decline in processing speed (Trail making test b). White matter volume expansion was observed after chemotherapy, only significantly present in the younger subgroup of patients. In patients not treated with chemotherapy, diffuse gray and white matter volume reduction was observed. Less white matter expansion concurred with more cognitive decline (r > .349, p < .05). In conclusion, we found age-dependent cognitive decline and white matter volume changes in patients with breast cancer after chemotherapy, which could possibly be linked to neuroinflammatory processes. White matter expansion after chemotherapy, more pronounced in premenopausal patients, correlated with less cognitive decline. This suggests such expansion to be age-dependent, possibly caused by a protective response in the younger brain to chemotherapy-induced neurotoxicity.

Neuroimmunology of the female brain across the lifespan: Plasticity to psychopathology

The female brain is highly dynamic and can fundamentally remodel throughout the normal ovarian cycle as well as in critical life stages including perinatal development, pregnancy and old-age. As such, females are particularly vulnerable to infections, psychological disorders, certain cancers, and cognitive impairments. We will present the latest evidence on the female brain; how it develops through the neonatal period; how it changes through the ovarian cycle in normal individuals; how it adapts to pregnancy and postpartum; how it responds to illness and disease, particularly cancer; and, finally, how it is shaped by old age. Throughout, we will highlight female vulnerability to and resilience against disease and dysfunction in the face of environmental challenges.

Depression involved in self-reported prospective memory problems in survivors of breast cancer who have received chemotherapy

To investigate the relationship between depression and the self-reported prospective memory (SPM) problems in breast cancer survivors who have received chemotherapy.Sixty-three breast cancer patients were administered with self-rating depression scale (SDS) and the prospective memory questionnaire as part of extensive neuropsychological assessments before and after chemotherapy. The performance of SDS and SPM were compared, with the level of significance set at P < .05.Compared with the group before chemotherapy, there is a significant difference on the SPM score (t = 6.069, P = .000) in breast cancer patients after chemotherapy. Further, there is also a significant difference on the SPM score (t = -4.348, P = .000) between the patients with and without depression group after chemotherapy.The present result indicated that the depression in breast cancer survivors after chemotherapy may be involved in their chemotherapy-induced SPM impairment.

Post-treatment with cotinine improved memory and decreased depressive-like behavior after chemotherapy in rats

PURPOSE

Most cancer patients treated with systemic adjuvant chemotherapy endure long-lasting side effects including decrease in concentration, forgetfulness and slower thinking, which are globally termed "chemobrain." Cotinine, the main derivative of nicotine, improved visual and spatial working memory and decreased depressive-like behavior in an animal model of chemotherapy-induced cognitive impairment.

METHODS

In this study, we investigated the effect of cotinine on weight gain, locomotor activity, cognitive abilities and depressive-like behavior in rats treated with the chemotherapy mix, cyclophosphamide, methotrexate and 5-fluorouracil. Locomotor activity and depressive-like behavior were assessed using the rotarod and Porsolt's tests, respectively. Changes in cognitive abilities were determined using the novel place recognition test.

RESULTS

Female rats treated with cotinine after chemotherapy, recovered weight faster, showed superior cognitive abilities and lower levels of depressive-like behavior than chemotherapy, vehicle-treated rats.

CONCLUSIONS

This evidence suggests that treatment with cotinine may facilitate the recovery and diminish the cognitive consequences of chemotherapy.

Can Exercise Ameliorate Aromatase Inhibitor-Induced Cognitive Decline in Breast Cancer Patients?

Aromatase inhibitors (AIs) have been commonly used as an effective adjuvant therapy in treatment of breast cancer, especially for menopausal women with estrogen receptor-positive breast cancer. Due to the nature of aromatase, the key enzyme for endogenous estrogen synthesis, inhibitory of aromatase-induced side effects, such as cognitive impairment has been reported in both human and animal studies. While extensive evidence suggested that physical exercises can improve learning and memory activity and even prevent age-related cognitive decline, basic research revealed some common pathways between exercise and estrogen signaling that affected cognitive function. This review draws on clinical and basic studies to assess the potential impact of exercise in cognitive function from women treated with AIs for breast cancer and explore the potential mechanism and effects of exercise on estrogen-related cognition.

Long-term trajectories of self-reported cognitive function in a cohort of older survivors of breast cancer: CALGB 369901 (Alliance)

BACKGROUND

The number of survivors of breast cancer aged ≥65 years (“older”) is growing, but to the authors' knowledge, little is known regarding the cognitive outcomes of these individuals.

METHODS

A cohort of cognitively intact older survivors with nonmetastatic, invasive breast cancer was recruited from 78 sites from 2004 through 2011; approximately 83.7% of the survivors (1280 survivors) completed baseline assessments. Follow‐up data were collected at 6 months and annually for up to 7 years (median, 4.1 years). Cognitive function was self‐reported using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ‐C30); scores ranged from 0 to 100, with a higher score indicating better function. Group‐based trajectory modeling determined trajectories; women were assigned to a trajectory group based on the highest predicted probability of membership. Multinomial logistic regression evaluated the association between receipt of chemotherapy (with or without hormonal treatment) and trajectory group.

RESULTS

Survivors were aged 65 to 91 years; approximately 41% received chemotherapy. There were 3 cognitive trajectories: “maintained high” (42.3% of survivors); “phase shift” (50.1% of survivors), with scores slightly below but parallel to maintained high; and “accelerated decline” (7.6% of survivors), with the lowest baseline scores and greatest decline (from 71.7 [standard deviation, 19.8] to 58.3 [standard deviation, 21.9]). The adjusted odds of being in the accelerated decline group (vs the maintained high group) were 2.1 times higher (95% confidence interval, 1.3‐3.5) for survivors who received chemotherapy (with or without hormonal therapy) versus those treated with hormonal therapy alone. Greater comorbidity and frailty also were found to be associated with accelerated decline.

CONCLUSIONS

Trajectory group analysis demonstrated that the majority of older survivors maintained good long‐term self‐reported cognitive function, and that only a small subset who were exposed to chemotherapy manifested accelerated cognitive decline. Future research is needed to determine factors that place some older survivors at risk of experiencing cognitive decline. Cancer 2016;122:3555–3563. © 2016 American Cancer Society

Among older survivors of breast cancer who were followed for up to 7 years, approximately 42% reported maintaining high cognitive function, but receipt of chemotherapy (with or without hormonal therapy) appeared to double the odds of being in the group that reported accelerated cognitive decline (vs maintaining high function), compared with receiving hormonal treatment alone. Further research is needed to determine factors that place some older survivors at risk of experiencing cognitive decline.

Safety of aromatase inhibitor therapy in breast cancer

INTRODUCTION

Aromatase inhibitor (AI) therapy is the current preferred choice of endocrine therapy in postmenopausal estrogen receptor-positive breast cancer patients thanks to their improved effectiveness compared to tamoxifen. Despite the absence of increased endometrial pathology and deep venous thrombosis seen in tamoxifen-users, the safety profile of AIs consists of a variety of bothersome side effects negatively influencing daily functioning.

AREAS COVERED

Besides the well-known adverse effects on joints and bone and the vasomotor system, more neglected and latent toxicity like cognitive problems and vulvovaginal atrophy will be discussed. Concern has been raised in terms of increased risk of fractures and cardiovascular events with chronic AI use.

EXPERT OPINION

Placebo-controlled long-term studies carefully monitoring these adverse events, together with more extensive research in the etiologies, are warranted.