A meta-analysis of the neuropsychological effects of adjuvant chemotherapy treatment in women treated for breast cancer

Memory Impairments and Wellbeing in Breast Cancer Patients: A Systematic Review

Breast cancer is one of the most diagnosed cancers among women. Its effects on the cognitive and wellbeing domains have been widely reported in the literature, although with inconsistent results. The central goal of this review was to identify, in women with breast cancer, the main memory impairments, as measured by objective and subjective tools and their relationship with wellbeing outcomes. The systematic literature search was conducted in the PubMed, Scopus, and ProQuest databases. The selected studies included 9 longitudinal and 10 cross-sectional studies. Although some studies included participants undergoing multimodal cancer therapies, most focused on chemotherapy's effects (57.89%; n = 11). The pattern of results was mixed. However, studies suggested more consistently working memory deficits in breast cancer patients undergoing chemotherapy. In addition, some associations have been identified between objective memory outcomes (verbal memory) and wellbeing indicators, particularly depression and anxiety. The inconsistencies in the results could be justified by the heterogeneity of the research designs, objective and subjective measures, and sample characteristics. This review confirms that more empirical evidence is needed to understand memory impairments in women with breast cancer. An effort to increase the homogeneity of study methods should be made in future studies.

Cognitive intra-individual variability in breast cancer survivors: A systematic review

Subjective and objective cognitive impairments in Breast Cancer Survivors (BCS) often do not correlate. One important contribution to the reported disparities may be the reliance on mean-based cognitive performance. Cognitive intra-individual variability (IIV) may provide important insights into these reported disparities. Cognitive IIV refers to the fluctuation in performance for an individual on either one cognitive task across a trial or dispersed across tasks within a neuropsychological test battery. The purpose of this systematic review was to search for and examine the literature on cognitive IIV in BCS. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) approach was used to search for all articles related to cognitive IIV in BCS. MEDLINE (via PubMed), Embase, and Scopus databases were searched using detailed search terms and strategies. Initially, 164 articles were retrieved but only 4 articles met the criteria for this systematic review. BCS differed from healthy controls in similar ways across the four studies, generally demonstrating similar performance but showing increased cognitive IIV for the more difficult tasks. Differences were enhanced later during chemotherapy. The four studies provide support for cognitive IIV as a useful measure to detect the subtle objective cognitive change often reported by BCS but frequently not detected by standard normed-based cognitive testing. Unexpectedly, measures of cognitive IIV were not consistently associated with self-reported measures of cognition.

Association Between Cardiovascular Disease and Cognitive Dysfunction in Breast Cancer Survivors

BACKGROUND

Breast cancer survivors (BCSs) may have a greater risk for cardiovascular disease (congestive heart failure and hypertension), which in turn, can affect cognitive dysfunction, a frequent, bothersome, and potentially debilitating symptom.

OBJECTIVE

The purpose of this study was to examine the relationship of cardiovascular disease on cognitive function in BCSs.

METHODS

Baseline data from a double-blind randomized controlled trial for cognitive training of BCSs were examined. Early-stage BCS (stages I-IIIA) who were 21 years or older, completed adjuvant therapy (≥6 months), and reported cognitive concerns completed questionnaires and a brief neuropsychological assessment, including tests of memory, attention and working memory, speed of processing, and verbal fluency. Descriptive statistics, Pearson correlation coefficient, and separate linear regression models for each cognitive domain were conducted.

RESULTS

Forty-seven BCSs, who were on average 57.3 (SD, 8.1) years old, were 58% White, and had some college education (75%), completed the study. Furthermore, 44.7% of the BCS had cardiovascular disease (congestive heart failure or hypertension). In linear regression models, cardiovascular disease was significantly related to immediate and delayed memory and attention and working memory ( P < .01-.05).

CONCLUSION

Breast cancer survivors who have cardiovascular disease may also be at a greater risk for cognitive dysfunction post treatment. Results from this study inform both clinical practice and future research, specifically by examining the intersection between cancer, cardiovascular disease (cardiotoxicity), and cognition.

IMPLICATIONS FOR PRACTICE

Nurses should be aware that BCSs with co-occurring cardiovascular disease are at a higher risk for cognitive dysfunction and work within the multidisciplinary team to optimize BCS health and function.

Initial encoding deficits with intact memory retention in older long-term breast cancer survivors

PURPOSE

Cancer survivors frequently report significant forgetfulness, but standard neuropsychological tests often fail to detect primary memory deficits. Past research has suggested survivors may misattribute forgetfulness to memory decay rather than impairments in initial encoding, but no studies have tested whether this pattern is evident in older survivors, who are more vulnerable to age-related memory difficulties. We examined whether long-term breast cancer survivors treated in older adulthood demonstrate deficits in initial encoding, as opposed to increased rates of memory decay, relative to non-cancer controls.

METHODS

Three hundred twenty-eight breast cancer survivors age 60 and above, 5-15 years post-treatment, and 162 age-matched non-cancer controls completed list learning and narrative memory assessments at four time-points over 2 years. Performance on learning trials and delayed recall was analyzed at each time-point to assess group differences in memory encoding, and memory decay was assessed by analyzing changes in performance across delays.

RESULTS

Univariate ANCOVAs correcting for age and education showed that survivors had worse initial encoding performance across multiple time-points, which were compensated for with multiple learning trials to produce recall performance comparable to controls. There were no significant group differences in memory decay.

CONCLUSIONS

Older long-term breast cancer survivors exhibit a consistent pattern of initial encoding deficits, but memory retention was comparable to controls. Future research should consider the role of encoding deficits and age-related factors when evaluating cognitive function in older survivors.

IMPLICATIONS FOR CANCER SURVIVORS

Commonly reported memory problems may stem from encoding deficits in older long-term cancer survivors.

Modulation of mitochondrial dynamics rescues cognitive function in rats with 'doxorubicin-induced chemobrain' via mitigation of mitochondrial dysfunction and neuroinflammation

Doxorubicin (DOX), an effective, extensively used chemotherapeutic drug, can cause cognitive deterioration in cancer patients. The associated debilitating neurological sequelae are referred to as chemobrain. Our recent work demonstrated that Dox treatment resulted in an imbalance in mitochondrial dynamics, ultimately culminating in cognitive decline in rats. Therefore, in this study, we aim to explore the therapeutic efficacy of a pharmacological intervention, which modulates mitochondrial dynamics using a potent mitochondrial fission inhibitor (Mdivi-1) and mitochondrial fusion promoter (M1) against Dox-induced chemobrain. In the study, male Wistar rats were randomly assigned to receive either normal saline solution or six doses of Dox (3 mg·kg-1 ) via intraperitoneal injection. Then, the Dox-treated rats were intraperitoneally given either 1% DMSO as the vehicle, Mdivi-1 (1.2 mg·kg-1 ), M1 (2 mg·kg-1 ), or a combined treatment of Mdivi-1 and M1 for 30 consecutive days. Long-term learning and memory were evaluated using the novel object location task and novel object recognition task. Following euthanasia, the rat brains were dissected to enable further molecular investigation. We demonstrated that long-term treatment with mitochondrial dynamic modulators suppressed mitochondrial fission in the hippocampus following Dox treatment, leading to an improvement in brain homeostasis. Mitochondrial dynamic modulator treatments restored cognitive function in Dox-treated rats by attenuating neuroinflammation, decreasing oxidative stress, preserving synaptic integrity, reducing potential Alzheimer's related lesions, and mitigating both apoptosis and necroptosis following Dox administration. Together, our findings suggested that mitochondrial dynamics modulators protected against Dox-induced cognitive impairment by rebalancing mitochondrial homeostasis and attenuating both oxidative and inflammatory insults.

Comparative analysis of the chemotherapy-related cognitive impairments in patients with breast cancer: a community-based research

This study aimed to evaluate the effects of two common chemotherapy regimens on breast cancer (BC) survivors' cognition. The participants comprised 35 patients with BC who underwent two chemotherapy regimens, AC-T and TAC, and 24 matched healthy volunteers. The participants were assessed regarding cognitive function through Addenbrooke's Cognitive Examination and Cambridge Brain Science tests. The results represent the AC-T regimen to be more toxic than the TAC in domains of language, concentration, and visuospatial working memory (P-value =0.036, 0.008, and 0.031, respectively) and should be prescribed with caution in patients with BC suffering from baseline cognitive impairments.

Longitudinal Trajectories of Memory Performance in Patients with Early-Stage Breast Cancer

Background. While breast cancer and its treatments may affect cognition, the longitudinal trajectories of cognition among those receiving differing cancer treatment types remain poorly understood. Prior research suggests hippocampal-prefrontal cortex network integrity may influence cognition, although how this network predicts performance over time remains unclear. Methods. We conducted a prospective trial including 69 patients with early-stage breast cancer receiving adjuvant therapy and 12 controls. Longitudinal cognitive testing was conducted at four visits: pretreatment-baseline, 6-7 months, 14-15 months, and 23-24 months. Cognitive composite scores of episodic memory, executive functioning, and processing speed were assessed at each timepoint. Baseline structural MRI was obtained in a subset of these participants, and hippocampal and prefrontal cortex regional volumes were extracted. Results. Longitudinal linear mixed modeling revealed significant group by time interactions on memory performance, controlling for age and education. Post hoc analyses revealed this effect was driven by patients treated with chemotherapy or chemotherapy plus hormone therapy, who demonstrated the least improvement in memory scores over time. Treatment group did not significantly influence the relationship between time and processing speed or executive functioning. Neither pretreatment hippocampal nor prefrontal volume differed between groups, and there were no significant group by time by baseline regional volume effects on cognition. Conclusion. Patients with early-stage breast cancer treated with chemotherapy or chemotherapy plus hormone therapy benefit less from practice effects seen in healthy controls on memory tests. Loss of longitudinal practice effect may be a new and clinically relevant measure for capturing patients’ experience of cognitive difficulties after treatment.

Cognitive Dysfunction in Older Breast Cancer Survivors: An Integrative Review

BACKGROUND

Approximately 60% of the more than 3.8 million breast cancer survivors (BCSs) living in the United States are 60 years or older. Breast cancer survivors experience many symptoms including cognitive dysfunction; however, little is known regarding how age affects these symptoms.

OBJECTIVE

This integrative review was conducted to synthesize the literature on cognitive dysfunction in older BCSs. The purpose was to (1) describe the prevalence of objective and subjective cognitive dysfunctions and (2) examine factors associated with cognitive dysfunction in older BCSs.

METHODS

Whittemore and Knafl's integrative review methodology was used to examine cognitive dysfunction in BCSs 60 years or older.

RESULTS

Twelve quantitative studies were included. Up to 41% of older BCSs experienced cognitive dysfunction on neuropsychological examination, and up to 64% reported cognitive dysfunction on subjective measures pretreatment. Approximately half of older BCSs experienced cognitive decline from pretreatment to posttreatment regardless of cognitive measure. The domains most impacted were memory, executive functioning, and processing speed. Objective and subjective cognitive dysfunctions were associated with age, comorbidities, chemotherapy receipt, sleep, neuropsychological symptom cluster, frailty, and quality of life.

CONCLUSIONS

Cognitive dysfunction among older BCSs was common both prior to and following treatment. Cognitive dysfunction was associated with multiple factors that are compounded in the aging population and could be detrimental to quality of life and independent living.

IMPLICATIONS TO PRACTICE

Early assessment and intervention by healthcare providers, including nurses, for cognitive dysfunction in older BCSs are essential. Future research should focus on evidence-based interventions for cognitive dysfunction incorporating the unique needs of older BCSs.

Health-Related Quality of Life: Longitudinal Analysis From the Time of Breast Biopsy Into the Post-treatment Period

Background: The physical, psychological, social, and spiritual quality of life (QoL) may be affected by breast cancer diagnosis and treatment, with mixed findings for psychological quality of life and cognitive ability performance. The present study aimed to evaluate QoL in women over 1 year from biopsy for a breast abnormality. Methods: Self-reported measures of physical, psychological, social, and spiritual QoL were obtained after biopsy results but prior to treatment initiation (baseline), 4 and 12 months later. CogState computerized neuropsychological screening battery also provided an evaluation of psychological QoL. Three groups of women including those with benign biopsy results, those with malignancy treated with chemotherapy, and those with malignancy not treated with chemotherapy were compared at 4 and 12 months after adjusting for baseline to isolate the effects of treatment. Additional covariates included are age, level of education, and income. Results: Benign biopsy results group included 72 women, whereas malignancy was found in 87 women of whom 33 were treated with chemotherapy and 54 without chemotherapy. At the time of diagnosis, women with cancer had worse psychological and social QoL but better spiritual QoL than those with benign biopsy results. Only CogState monitoring accuracy was worse for women with cancer compared with the controls at the time of biopsy results. After adjusting for QoL at baseline, women treated for cancer had worse physical and social QoL at 4 and 12 months later. Psychological well-being was worse for women with cancer at 4th month but improved at 1 year. No differences in cognition were found at 4 and 12 months when adjusted for baseline cognition and covariates. Discussion: Breast cancer is a traumatic life event for women, affecting psychological and social QoL domains, yet increasing spiritual QoL. Later, cancer treatment worsens physical, psychological, and social QoL compared with those without cancer. Conclusions: These findings suggest that interventions to improve psychological QoL may be especially important at the time of cancer diagnosis, while interventions to improve physical well-being are the most needed during and following cancer treatment. Support to improve social QoL is needed from the time of diagnosis into post-treatment survivorship.

Sex-Specific Differences in Toxicity Following Systemic Paclitaxel Treatment and Localized Cardiac Radiotherapy

Simple Summary

The objective of the present study was to investigate the impact of sex in the development of long-term toxicities affecting quality of life in cancer survivors after systemic paclitaxel treatment and cardiac irradiation. Sex-specific differences may affect tumor biology, drug pharmacokinetics and dynamics, and response to local treatment such as radiation therapy (RT). However, sex is rarely taken into consideration when administering cancer therapies. Interestingly, female mice are protected from paclitaxel-induced neurotoxicity as well as from radiotherapy-induced cardiotoxicity, and deficiency in the small GTPase RhoB reversed the protection in females but not in males. In conclusion, our results are the first to identify sex- and organ-specific responses to systemic paclitaxel administration and localized RT. These results may have important implications for the management of cancer patients and implementation of personalized medicine in oncology.

Abstract

The impact of sex in the development of long-term toxicities affecting the quality of life of cancer survivors has not been investigated experimentally. To address this issue, a series of neurologic and cardiologic endpoints were used to investigate sex-based differences triggered by paclitaxel treatment and radiotherapy exposure. Male and female wild-type (WT) mice were treated with paclitaxel (150 and 300 mg/kg) administered weekly over 6 weeks or exposed to 19 Gy cardiac irradiation. Cohorts were analyzed for behavioral and neurobiologic endpoints to assess systemic toxicity of paclitaxel or cardiovascular endpoints to assess radiotherapy toxicity. Interestingly, female WT mice exhibited enhanced tolerance compared to male WT mice regardless of the treatment regimen. To provide insight into the possible sex-specific protective mechanisms, rhoB-deficient animals and elderly mice (22 months) were used with a focus on the possible contribution of sex hormones, including estrogen. In females, RhoB deficiency and advanced age had no impact on neurocognitive impairment induced by paclitaxel but enhanced cardiac sensitivity to radiotherapy. Conversely, rhoB-deficiency protected males from radiation toxicity. In sum, RhoB was identified as a molecular determinant driving estrogen-dependent cardioprotection in female mice, whereas neuroprotection was not sex hormone dependent. To our knowledge, this study revealed for the first time sex- and organ-specific responses to paclitaxel and radiotherapy.

Pharmacological rescue of cognitive function in a mouse model of chemobrain

BACKGROUND

After chemotherapy, many cancer survivors suffer from long-lasting cognitive impairment, colloquially known as "chemobrain." However, the trajectories of cognitive changes and the underlying mechanisms remain unclear. We previously established paclitaxel-induced inositol trisphosphate receptor (InsP3R)-dependent calcium oscillations as a mechanism for peripheral neuropathy, which was prevented by lithium pretreatment. Here, we investigated if a similar mechanism also underlay paclitaxel-induced chemobrain.

METHOD

Mice were injected with 4 doses of 20 mg/kg paclitaxel every other day to induced cognitive impairment. Memory acquisition was assessed with the displaced object recognition test. The morphology of neurons in the prefrontal cortex and the hippocampus was analyzed using Golgi-Cox staining, followed by Sholl analyses. Changes in protein expression were measured by Western blot.

RESULTS

Mice receiving paclitaxel showed impaired short-term spatial memory acquisition both acutely 5 days post injection and chronically 23 days post injection. Dendritic length and complexity were reduced in the hippocampus and the prefrontal cortex after paclitaxel injection. Concurrently, the expression of protein kinase C α (PKCα), an effector in the InsP3R pathway, was increased. Treatment with lithium before or shortly after paclitaxel injection rescued the behavioral, cellular, and molecular deficits observed. Similarly, memory and morphological deficits could be rescued by pretreatment with chelerythrine, a PKC inhibitor.

CONCLUSION

We establish the InsP3R calcium pathway and impaired neuronal morphology as mechanisms for paclitaxel-induced cognitive impairment. Our findings suggest lithium and PKC inhibitors as candidate agents for preventing chemotherapy-induced cognitive impairment.

Increased resting-state cerebellar-cortical connectivity in breast cancer survivors with cognitive complaints after chemotherapy

Cognitive complaints after chemotherapy are common in breast cancer patients, but the neural bases for these complaints remain unclear. This pilot study explored resting-state functional connectivity (FC) as a marker of subtle cognitive changes in breast cancer patients who experience cognitive complaints. Chemotherapy-treated (n = 20, at least 6 months off therapy) and untreated (n = 17, disease-control) female breast cancer patients with cognitive complaints and healthy controls (n = 20) were recruited. The FC of the right dorsolateral prefrontal cortex was calculated, and any correlations between this FC and neuropsychological assessments were determined. Chemotherapy-treated patients with cognitive complaints displayed increased FC between the right dorsolateral prefrontal cortex and both the contralateral cerebellar lobule VII and the cerebellar vermis XI, compared to the disease-control and healthy-control groups, despite unimpaired neuropsychological performance. The increased FC was negatively correlated with executive function and attention in breast cancer survivors with cognitive complaints. Our pilot study findings provide evidence that cerebellar-cortical FC changes may be a pathophysiological basis for chemotherapy-related cognitive complaints. In addition, the FC changes have the potential to reflect minor or compensated cognitive function impairment in breast cancer patients.

Structural Neuroimaging Findings Related to Adult Non-CNS Cancer and Treatment: Review, Integration, and Implications for Treatment of Cognitive Dysfunction

Cancer- and treatment-related cognitive dysfunction (CRCD) is a common challenge faced by patients diagnosed with non-central nervous system (CNS) cancer. It has become increasingly recognized that multiple factors likely play a role in these symptoms, including the cancer disease process, systemic treatments (e.g., chemotherapy and endocrine therapies), and risk factors that may predispose an individual to both cancer and cognitive dysfunction. As the field has evolved, advanced neuroimaging techniques have been applied to better understand the neural correlates of CRCD. This review focuses on structural neuroimaging findings related to CRCD in adult non-CNS cancer populations, including examination of gray matter volume/density and white matter integrity differences between cancer patients and comparison groups, as well as emerging findings regarding structural network abnormalities. Overall, this literature has demonstrated consistent findings of reduced gray matter volume/density and white matter integrity in cancer patients relative to comparison groups. These are most prominent in individuals treated with chemotherapy, though alterations have also been noted in those treated with anti-estrogen and androgen-deprivation therapies. Alterations in gray and white matter structural network connectivity have also been identified. These structural abnormalities have been observed most prominently in frontal and temporal brain regions, and have been shown to correlate with subjective and objective cognitive function, as well as with physiological and clinical variables, helping to inform understanding of CRCD mechanisms. To date, however, structural neuroimaging techniques have not been utilized in systematic studies of potential CRCD treatments, suggesting a potentially fruitful avenue for future research.

Neurocognitive Effects of Chemotherapy for Colorectal Cancer: A Systematic Review and a Meta-Analysis of 11 Studies

Purpose

Chemotherapy-related cognitive impairment (CRCI) is a controversial concept not much explored on colorectal cancer patients.

Materials and Methods

We identified 11 prospective studies: eight studies on 696 colorectal cancer patients who received chemotherapy and three studies on 346 rectal cancer patients who received neoadjuvant chemoradiotherapy. Standardized mean differences (SMDs) of neuropsychological test results and the cognitive quality-of-life scale were calculated using random effect models. A meta-regression was conducted to investigate the association between mean study population age and effect sizes.

Results

The association between chemotherapy and cognitive impairment was not clear in colorectal cancer patients (SMD, 0.003; 95% confidence interval, −0.080 to 0.086). However, a meta-regression showed that older patients are more vulnerable to CRCI than younger patients (β=–0.016, p < 0.001).

Conclusion

Chemotherapy has an overall positive negligible effect size on the cognitive function of colorectal patients. Age is a significant moderator of CRCI.

Prevalence of cognitive impairment and change in patients with breast cancer: A systematic review of longitudinal studies

OBJECTIVE

Patients with breast cancer face cognitive impairment that affects their quality of life; partially attributable to treatment. Our aim was to detail the prevalence and change of cognitive impairment during the course of treatment. We also investigated the effect of therapy (chemotherapy [CT]) vs. radiotherapy and/or endocrine therapy vs. healthy controls).

METHODS

This article reviews longitudinal cohort studies published to date in Medline and Embase that (i) assess cognition before and after therapy, (ii) report prevalence cognitive impairment or change, and (iii) use standardized and valid neuropsychological tests. We used the original authors' criteria for cognitive impairment.

RESULTS

The title and abstract of 891 articles were screened, resulting in the identification of 90 potentially relevant articles while applying the eligibility criteria. After full-text examination, 17 studies were included. Prevalence of cognitive impairment range from 25% before therapy, through 24% after therapy to 21% at maximal 1-year follow-up (FU). Compared to their pretreatment cognitive functioning, 24% of patients decline after treatment and 24% at 1-year FU. Some studies also reported cognitive improvement showing that 15% and 31% of patients improve, respectively. In general, patients undergoing CT have a higher chance of cognitive impairment and decline than no-CT patients and healthy controls.

CONCLUSIONS

This study shows that one out of four breast cancer patients shows cognitive impairment prior to treatment administration CT and a significant number of patients decline during the course of disease, suggesting that cognitive impairment is not exclusively related to CT and/or no-CT therapies. This study shows that assessment of cognitive functioning, ideally over time, is crucial and may help the implementation of personalized rehabilitation pathways.

Relationship of perceived everyday cognitive function and work engagement in breast cancer survivors

INTRODUCTION

Breast cancer survivors (BCS) who represent approximately 3.5 million survivors in the USA frequently report ongoing cognitive dysfunction that may impact work outcomes. However, little is known about how perceived everyday cognitive function may affect work engagement (a measure of work efficacy and work well-being) in BCS who have completed treatment.

OBJECTIVES

The purpose of this study was to examine the relationship between perceived everyday cognitive function and work engagement in BCS.

METHODS

A convenience sample of 68 employed BCS seen at a Midwest NCI-Cancer Center who were at least 1-year post-treatment, completed a cross-sectional questionnaire assessing demographic and medical characteristics, and perceived everyday cognitive function (Everyday Cognition Scale) and work engagement (Utrecht Work Engagement Scale). Descriptive statistics, Pearson's r, and separate regression models controlling for age and education were used to analyze the data.

RESULTS

BCS who were on average 52 (SD = 8.6) years old, 5 (SD = 3.8) years post-treatment, and primarily employed full-time (79%) participated. A subset of BCS (12%) identified poorer everyday cognitive function after BC diagnosis and treatment. Everyday cognition, including subscales vigor and dedication, were correlated with work engagement (p˂0.01), controlling for age and education.

CONCLUSIONS

Findings indicate the important role of perceived everyday cognitive function in work engagement well into survivorship. Reducing cognitive dysfunction may be an important area for future intervention research to support BCS who return to work.

IMPLICATIONS TO PRACTICE

Healthcare providers need to assess and address perceived cognitive dysfunction to promote work-related outcomes in BCS well into survivorship.

A narrative review of risk factors and interventions for cancer-related cognitive impairment

Cancer-related cognitive impairment (CRCI) refers to a series of cognitive impairment symptoms associated with alternations in brain structure and function, caused by a non-central nervous system malignant tumor and its related treatment. CRCI may present as memory loss, impaired concentration, difficulty in multitasking and word retrieval, and reduced comprehension speed. CRCI has become one of the prevalent factors that compromise the quality of life for cancer survivors. Different treatments, including surgery, chemotherapy, radiotherapy, endocrine therapy, and targeted drugs, may contribute to CRCI. Meanwhile, patients’ factors, including emotional challenges and genetic makeup, also contribute to the development of CRCI. The condition can be treated with using stimulants methylphenidate and modafinil, metabolites of nicotine: cotinine, antidepressants of fluoxetine and fluvoxamine, dementia drug of donepezil, and antioxidants ZnSO4, n-acetyl cysteine, propofol, and Chinese herbal of silver leaf medicine. Psychotherapies, including meditation and relaxation, cognitive rehabilitation training, along with physical therapies, including aerobic exercise, resistance training, balance training, yoga, qigong, tai chi electroencephalogram biofeedback, and acupuncture, are also beneficial in alleviating cancer-related cognitive impairment symptoms. In recent years, researchers have focused on factors related to the condition and on the available interventions. However, most research was conducted independently, and no review has yet summarized the latest findings. This review details and discusses the status of related factors and potential treatments for CRCI. We also supply specific recommendations to facilitate future research and integration in this field.

Longitudinal investigation of cognitive deficits in breast cancer patients and their gray matter correlates: impact of education level

Cognitive deficits are a major complaint in breast cancer patients, even before chemotherapy. Comprehension of the cerebral mechanisms related to cognitive impairment in breast cancer patients remains difficult due to the scarcity of studies investigating both cognitive and anatomical imaging changes. Furthermore, only some of the patients experienced cognitive decline following chemotherapy, yet few studies have identified risk factors for cognitive deficits in these patients. It has been shown that education level could impact cognitive abilities during the recovery phase following chemotherapy. Our main aim was to longitudinally evaluate cognitive and anatomical changes associated with cancer and chemotherapy in breast cancer patients. Our secondary aim was to assess the impact of education level on cognitive performances and gray matter (GM) atrophy in these patients. Twenty patients were included before chemotherapy (T1), 1 month (T2) and 1 year (T3) after chemotherapy. Twenty-seven controls without a history of cancer were assessed at T1 and T3 only. Cluster groups based on education level were defined for both groups and were further compared. Comparison between patients and controls revealed deficits in patients on verbal episodic memory retrieval at T1 and T3 and on executive functions at T3. After chemotherapy, breast cancer patients had GM atrophy that persisted or recovered 1 year after chemotherapy depending on the cortical areas. Increase in GM volumes from T1 to T3 were also found in both groups. At T2, patients with a higher level of education compared to lower level exhibited higher episodic memory retrieval and state anxiety scores, both correlating with cerebellar volume. This higher level of education group exhibited hippocampal atrophy. Our results suggest that, before chemotherapy, cancer-related processes impact cognitive functioning and that this impact seems exacerbated by the effect of chemotherapy on certain brain regions. Increase in GM volumes after chemotherapy were unexpected and warrant further investigations. Higher education level was associated, 1 month after the end of chemotherapy, with greater anxiety and hippocampal atrophy despite a lack of cognitive deficits. These results suggest, for the first time, the occurrence of compensation mechanisms that may be linked to cognitive reserve in relationship to state anxiety. This identification of factors, which may compensate cognitive impairment following chemotherapy, is critical for patient care and quality of life.

Quality of life and mental health in breast cancer survivors compared with non-cancer controls: a study of patient-reported outcomes in the United Kingdom

PURPOSE

There is limited high-quality evidence on quality of life, anxiety, and depressive symptoms in breast cancer survivors and women with no history of cancer. We aimed to address this by comparing patient-reported outcomes between breast cancer survivors and women with no history of breast cancer.

METHODS

Breast cancer survivors and women with no prior cancer were selected from the UK Clinical Practice Research Datalink GOLD primary care database, which includes population-based primary care electronic health record data. Breast cancer survivors and controls were frequency matched by age and primary care practice. Outcomes were assessed with validated instruments via postal questionnaire. Linear and logistic regression models were fitted to estimate adjusted associations between breast cancer survivorship and outcomes.

RESULTS

A total of 356 breast cancer survivors (8.1 years post diagnosis) and 252 women with no prior cancer participated in the study. Compared with non-cancer controls, breast cancer survivors had poorer QoL in the domains of cognitive problems (adjusted β (aβ) = 1.4, p = 0.01), sexual function (aβ = 1.7, p = 0.02) and fatigue (aβ = 1.3, p = 0.01), but no difference in negative feelings, positive feelings, pain, or social avoidance. Breast cancer survivors had higher odds of borderline-probable anxiety (score ≥ 8) (adjusted OR = 1.47, 95%CI:1.15-1.87), but no differences in depression. Advanced stage at diagnosis and chemotherapy treatment were associated with poorer QoL.

CONCLUSIONS

Compared with women with no history of cancer, breast cancer survivors report more problems with cognition, sexual function, fatigue, and anxiety, particularly where their cancer was advanced and/or treated with chemotherapy.

IMPLICATIONS FOR CANCER SURVIVORS

Breast cancer survivors with more advanced disease and/or treated with chemotherapy should be closely monitored and, when possible, offered evidence-based intervention for fatigue, cognitive dysfunction, and sexual problems.

The acceleration of ageing in older patients with cancer

Older cancer survivors may experience ageing at an accelerated rate when compared to their similar-aged, cancer-free counterparts. Ageing is undoubtedly a significant risk factor for cancer. There is evidence to suggest, however, that this relationship may in fact be bidirectional, with cancer and its treatments contributing to the ageing process. In this review, we outline the current literature linking cancer and anti-cancer therapy to adverse ageing outcomes and explore what additional research is needed in order to conclusively define cancer and its treatment as an accelerator of ageing.

Study protocol of the Aerobic exercise and CogniTIVe functioning in women with breAsT cancEr (ACTIVATE) trial: a two-arm, two-centre randomized controlled trial

BACKGROUND

Up to 75% of women diagnosed with breast cancer report chemotherapy-related cognitive changes (CRCC) during treatment, including decreased memory, attention, and processing speed. Though CRCC negatively impacts everyday functioning and reduces overall quality of life in women diagnosed with breast cancer, effective interventions to prevent and/or manage CRCC are elusive. Consequently, women seldom receive advice on how to prevent or manage CRCC. Aerobic exercise is associated with improved cognitive functioning in healthy older adults and adults with cognitive impairments. Accordingly, it holds promise as an intervention to prevent and/or manage CRCC. However, evidence from randomized controlled trials (RCTs) supporting a beneficial effect of aerobic exercise on CRCC is limited. The primary aim of the ACTIVATE trial is to evaluate the impact of supervised aerobic exercise on CRCC in women receiving chemotherapy for breast cancer.

METHODS

The ACTIVATE trial is a two-arm, two-centre RCT. Women diagnosed with stage I-III breast cancer and awaiting neo-adjuvant or adjuvant chemotherapy are recruited from hospitals in Ottawa (Ontario) and Vancouver (British Columbia), Canada. Recruits are randomized to the intervention group (aerobic exercise during chemotherapy) or the wait-list control group (usual care during chemotherapy and aerobic exercise post-chemotherapy). The primary outcome is cognitive functioning as measured by a composite cognitive summary score (COGSUM) of several neuropsychological tests. Secondary outcomes are self-reported cognitive functioning, quality of life, and brain structure and functioning (measured by magnetic resonance imaging (MRI)/functional MRI and electroencephalography). Assessments take place pre-chemotherapy (pre-intervention), mid-way through chemotherapy (mid-intervention/mid-wait period), end of chemotherapy (post-intervention/post-wait period; primary endpoint), 16-weeks post-chemotherapy, and at 1-year post-baseline.

DISCUSSION

Aerobic exercise is a promising intervention for preventing and/or managing CRCC and enhancing quality of life among women diagnosed with breast cancer. The ACTIVATE trial tests several novel hypotheses, including that aerobic exercise can prevent and/or mitigate CRCC and that this effect is mediated by the timing of intervention delivery (i.e., during versus post-chemotherapy). Findings may support prescribing exercise during (or post-) chemotherapy for breast cancer and elucidate the potential role of aerobic exercise as a management strategy for CRCC in women with early-stage breast cancer.

TRIAL REGISTRATION

The trial was registered with the ClinicalTrials.gov database ( NCT03277898 ) on September 11, 2017.

Initial validation of the German version of the Attentional Function Index in a sample of haematological cancer survivors

OBJECTIVE

To date, no German instrument exists to assess subjective levels of cancer-related cognitive impairments (CRCI) in cancer survivors. We translated the validated Attentional Function Index (AFI) into German and explored its psychometric properties.

METHODS

The validation sample consisted of 1,111 haematological cancer survivors mainly recruited from two cancer registries. Factorial structure was explored using principal component analysis, internal consistency via Cronbach's α, construct validity through correlational analyses (Pearson's r) and associations of patient characteristics with the AFI score via regression analyses.

RESULTS

In line with the original version, we revealed three factors, that is "effective action" (seven items), "attentional lapses" (three items) and "interpersonal effectiveness" (three items). The overall reliability α was .91. Verifying construct validity, the AFI score correlated positively with cognitive functioning (r = .64, p ≤ .01) and global QoL (r = .44, p ≤ .01), but negatively with fatigue (r = -.60, p ≤ .01) and depressive symptomatology (r = -.6, p ≤ .01). Older age (β = .12, p < .001), higher comorbidity (β = -.07, p = .02) and being male patient (β = .07, p = .01) were significantly associated with the AFI scores, but effect sizes were small.

CONCLUSION

The German translation of the AFI shows good psychometric properties and thus may be reasonably applied to measure the subjective level of CRCI in German-speaking oncological populations.

Understanding the Profile of Cancer-Related Cognitive Impairments: A Critique of Meta-Analyses

A large body of evidence indicates that cancer survivors who have undergone chemotherapy have cognitive impairments. Substantial disagreement exists regarding which cognitive domains are impaired in this population. We suggest that is in part due to inconsistency in how neuropsychological tests are assigned to cognitive domains. The purpose of this paper is to critically analyze the meta-analytic literature on cancer-related cognitive impairments (CRCI) to quantify this inconsistency. We identified all neuropsychological tests reported in seven meta-analyses of the CRCI literature. Although effect sizes were generally negative (indicating impairment), every domain was declared to be impaired in at least one meta-analysis and unimpaired in at least one other meta-analysis. We plotted summary effect sizes from all the meta-analyses and quantified disagreement by computing the observed and ideal distributions of the one-way χ2 statistic. The actual χ2 distributions were noticeably more peaked and shifted to the left than the ideal distributions, indicating substantial disagreement among the meta-analyses in how neuropsychological tests were categorized to domains. A better understanding of the profile of impairments in CRCI is essential for developing effective remediation methods. To accomplish this goal, the research field needs to promote better agreement on how to measure specific cognitive functions.

Non-pharmacological interventions for cognitive impairment in women with breast cancer post-chemotherapy: A systematic review

PURPOSE

Cognitive impairment is a well-reported side-effect of chemotherapy in persons with breast cancer. Whilst non-pharmacological interventions have proven efficacious in the management of cognitive impairment in high-risk groups, their efficacy in cognitive impairment post-chemotherapy in patients with breast cancer remains unclear.

METHODS

Medline, CINAHL, PsycINFO, Web of Science and Cochrane were searched for randomized controlled trials of non-pharmacological interventions for cognitive impairment post-chemotherapy in women with breast cancer.

RESULTS

Of 429 results, 83 full-texts were reviewed with ten meeting inclusion criteria. Interventions included cognitive training, exercise and complementary therapies. The non-pharmacological interventions assessed displayed variable benefits in subjective and/or objective cognitive assessments, with no strong evidence for beneficial effects across included studies. No studies assessed the efficacy of multi-domain interventions.

CONCLUSIONS

There is mixed evidence supporting non-pharmacological interventions for cognitive impairment post-chemotherapy in women with breast cancer. Moving forward, multidomain trials combining non-pharmacological interventions are imperative in this high risk cohort.

Cellular mechanisms and treatments for chemobrain: insight from aging and neurodegenerative diseases

Chemotherapy is a life-saving treatment for cancer patients, but also causes long-term cognitive impairment, or "chemobrain", in survivors. However, several challenges, including imprecise diagnosis criteria, multiple confounding factors, and unclear and heterogeneous molecular mechanisms, impede effective investigation of preventions and treatments for chemobrain. With the rapid increase in the number of cancer survivors, chemobrain is an urgent but unmet clinical need. Here, we leverage the extensive knowledge in various fields of neuroscience to gain insights into the mechanisms for chemobrain. We start by outlining why the post-mitotic adult brain is particularly vulnerable to chemotherapy. Next, through drawing comparisons with normal aging, Alzheimer's disease, and traumatic brain injury, we identify universal cellular mechanisms that may underlie the cognitive deficits in chemobrain. We further identify existing neurological drugs targeting these cellular mechanisms that can be repurposed as treatments for chemobrain, some of which were already shown to be effective in animal models. Finally, we briefly describe future steps to further advance our understanding of chemobrain and facilitate the development of effective preventions and treatments.

Doxorubicin chemotherapy-induced "chemo-brain": Meta-analysis

Doxorubicin is a leading chemotherapeutic halting cellular replication and inducing p53-dependent apoptosis in cancerous tissue. Like many chemotherapies, doxorubicin damages healthy tissue throughout the body through cellular mechanisms independent of its chemotherapeutic action. Although cognitive impairment is commonly recorded in patients after chemotherapy, the occurrence of doxorubicin-induced "chemo-brain" is debated, as doxorubicin cannot cross the blood-brain barrier. However, the potential of indirect doxorubicin neurotoxicity remains, providing a foundation for doxorubicin-mediated chemo-brain. We present the first meta-analysis of defined cognitive performance of doxorubicin-treated patients. A search of PubMed and MedLine collected 494 studies, 14 of which met analysis criteria. Performance of 511 doxorubicin-treated women with breast cancer was compared to that of 306 healthy controls across measures of defined cognitive modalities. Treated patients experience significant impairment in global cognition compared to controls (g₌ -0.41, P < 0.001), with select impairment in executive function (g = -0.25, P < 0.0001), language (g = -0.30, P < 0.0001), memory (g = -0.12, P < 0.01) and processing speed (g = -0.28, P < 0.01). Within memory, short-term verbal memory is most significantly affected (g = -0.21, P < 0.01). Impairment in select cognitive modalities (executive function, language, memory, short-term verbal memory, processing speed) is prevalent in doxorubicin-treated patients, with some cognitive functions remaining intact (attention, motor function, visuospatial abilities). This information can guide the development of future interventions to improve quality-of-life (QOL) and doxorubicin-derived therapies that target cytotoxicity to cancerous tissue, avoiding healthy tissue damage, which is mediated by seemingly independent mechanisms.

Chemotherapy-related cognitive impairment in patients with breast cancer based on MRS and DTI analysis

The purpose of this study is to investigate chemotherapy-related cognitive impairment (CRCI) in breast cancer patients, analyze absolute concentration and structural changes of metabolites in different brain regions by multimodal neuroimaging technology, and explore correlation between them. Breast cancer patients with chemotherapy treatment group (Ctx+, N = 24) and control group without treatment (Ctx-, N = 20) underwent neuropsychological tests, multivoxel magnetic resonance spectroscopy (MRS), and diffusion tensor imaging (DTI) before and after chemotherapy. Regions of interest (ROls) in magnetic resonance scan include bilateral posterior cingulate gyrus (PCG), bilateral dorsal thalamus (DT), bilateral lenticular nucleus (LN), bilateral posterior horn of the lateral ventricle paratrigonal white matter (PWM). In MRS, absolute concentrations of N-acetylaspartate (NAA), myo-inositol (MI), choline-containing compounds (Cho), total creatine (tCr), glutamine + glutamate (Glx) were quantified using LC Model and SAGE software. In DTI, we used fractional anisotropy (FA) and mean diffusivity (MD) to reflect white matter integrity. In Ctx+ patients, scores of functional assessment of cancer treatment cognition test (FACT-Cog), perceived cognitive impairments (PCI), impact of perceived impairments on quality of life (QOL), perceived cognitive abilities (PCA), auditory-verbal learning test (AVLT) recognition and clock drawing test (CDT) were lower than those before chemotherapy (p < 0.05). In MRS, Ctx+ patients had significantly lower NAA values in bilateral PCG, DT, respectively. The concentrations of tCr were observed to decline in bilateral PCG and right DT. Glx values decreased in right DT. Cho values decreased significantly in bilateral DT. In DTI, Ctx+ patients had lower FA values in bilateral PCG compared with patients before chemotherapy. Among imaging metrics and cognitive scores, positive correlations were observed between changes in AVLT recognition scores and changes in NAA values in bilateral PCG (left PCG: r = 0.470, p < 0.01; right PCG: r = 0.500, p < 0.01). Positive correlations were also found between changes in AVLT recognition and changes in FA values in bilateral PCG (left PCG: r = 0.513, p < 0.01; right PCG: r = 0.563, p < 0.01). Chemotherapy can lead to a decrease in memory function, accompanied by changes in brain metabolite concentration and white matter integrity in some parts of brain.

Systematic review of longitudinal studies on chemotherapy-associated subjective cognitive impairment in cancer patients

OBJECTIVES

This systematic review of longitudinal studies, assessing subjective cognitive impairment (SCI) reported by adult cancer patients, aimed to summarize evidence on the impact of chemotherapy on SCI, identify moderators of SCI, and evaluate methodological issues.

METHODS

Data accrued from Pubmed, EMBASE, CINAHL, PsychInfo, and the Cochrane library. Inclusion criteria were original studies, an exclusively adult sample, valid and reliable subjective cognitive measures, and at least one baseline data point prior to and another after the initiation of chemotherapy. Data were collected on the sample composition, data-collection time points, outcome measures, statistical analysis, and major findings (ie, longitudinal changes in prevalence, severity, and associated factors).

RESULTS

Forty articles published between 2004 and 2019 were retained: 21 examined chemotherapy-treated patients only, and 19 employed control groups. Findings were mixed, with slightly more studies supporting the impact of chemotherapy on SCI. SCI tended to be more prevalent and severe after initiating chemotherapy, compared with patients' own baseline and controls not treated with chemotherapy. Impact appeared to be acute and more likely limited to subsamples. Most studies examining non-breast-cancer samples reported the lack or limited impact of chemotherapy on SCI. The most consistent moderators were depression and fatigue. Methodological issues regarding sampling design, measurement, and statistical analysis were discussed.

CONCLUSION

More rigorously designed longitudinal studies would clarify direct and indirect effects of chemotherapy on SCI.

Cognitive Rehabilitation for Cognitive Dysfunction after Cancer and Cancer Treatment: Implications for Nursing Practice

OBJECTIVE

To provide an overview of cognitive rehabilitation approaches for cognitive dysfunction after cancer and cancer treatment.

DATA SOURCES

Review and synthesis of empirical articles.

CONCLUSION

Cognitive rehabilitation approaches, including cognitive behavioral therapy and cognitive training, for cognitive dysfunction appear feasible to deliver, satisfactory to participants, and have shown promising results in cancer survivors. Future research is needed to address optimal dose, delivery method, access, cost, and the vulnerable aging cancer survivor population.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses must understand the available evidence and be able to provide information and options to cancer survivors to address cognitive changes after cancer.

Cognitive impairments in breast cancer survivors treated with chemotherapy: a study based on event-related potentials

PURPOSE

Chemotherapy-related cognitive impairments in breast cancer patients were usually reported through cognitive questionnaires or scales which may be subjective and insensitive. This study is to assess the effect of chemotherapy on cognitive function in breast cancer patients stratified by age using objective electrophysiological measure, the P300 component of event-related potentials (ERPs) with a large sample size.

METHODS

Totally, 529 primary breast cancer patients, including 178 cases at initial diagnosis stage and before chemotherapy (Group1), 167 cases during chemotherapy (Group2), and 184 cases post chemotherapy and during follow-up period (Group3), were examined with ERPs (P300 component) to assess the effect of chemotherapy on their cognitive function.

RESULTS

There were significant differences of P300 latency in Group2 (364.74 ± 15.73 ms) and Group3 (364.02 ± 17.12 ms, mean follow-up period of 2.42 years) compared with Group1 (355.13 ± 19.47 ms, P < 0.001), respectively. With further age stratification: in patients of < 50 years, P300 latency was significantly prolonged in Group2 and Group3 compared with Group1 (P < 0.001), respectively; in patients of 50-59 years, P300 latency was significantly prolonged in Group2 compared with Group1 (P < 0.05), but without difference in Group1 and Group3 (P>0.05); In patients of ≥ 60 years, there were no differences of P300 latency among three the groups (P>0.05).

CONCLUSIONS

It is first suggested by our objective detection data that the side effect of chemotherapy on cognitive functions in breast cancer patients may decrease with age. Electrophysiological cognitive impairments mainly occur in younger breast cancer patients undergoing chemotherapy and would last for years after chemotherapy, which highlights the importance of early intervention for those patients, especially in younger patients.

Role of stress, age and adjuvant therapy in the cognitive function of patients with breast cancer

According to data largely obtained from retrospective studies, it has been postulated that chemotherapy exerts an aggravating effect on the cognitive function of patients with breast cancer. Potential individual factors related to the effects of chemotherapy on cognitive function have been indicated, such as age-related cognitive dysfunction and stress. Elderly patients differ from non-elderly patients as regards higher cognitive related comorbidities, such as dementia, as well as regarding lower stress levels, indicating that 'chemobrain' may differentially affect these two age groups. The aim of this review was to discuss the effects of stress and chemotherapy on cognitive dysfunction and identify any potential age-related differences in patients with breast cancer treated with adjuvant chemotherapy. For this purpose, a systematic review of the literature was carried out on the PubMed, Scopus and Web of Science databases. The inclusion criteria were original articles published in peer-reviewed journals, elderly and non-elderly patients with breast cancer, reporting on stress and at least one cognitive parameter pre- and/or post-treatment. Eight studies met the preset criteria and were further analyzed. In total, the data of 1,253 women were included, of whom 800 patients with breast cancer were treated with surgery only, systemic treatment only, or both. Although all the studies included a non-elderly breast cancer patient subpopulation, only two of the studies included patients over 65 years of age. All studies indicated a statistically significant association of stress with various domains of cognitive dysfunction in patients, as shown by either self-completed questionnaires, neuropsychological testing or both. An age over 60 years was linked to fewer cognitive difficulties mediated by lower levels of stress. Thus, the evidence supports the association of stress with cognitive deficits in patients with breast cancer, regardless of the type of cancer-related treatment. Therefore, stress should be appropriately addressed. However, further research is required to investigate the association of stress with cognitive function in elderly patients with breast cancer.

Functional Impairments and Work-Related Outcomes in Breast Cancer Survivors: A Systematic Review

Purpose Work participation after breast cancer treatment is generally negatively affected. Occupational health professionals might improve work-related outcomes by bridging the gap between sick-listed employees' levels of functioning and work demands. To aid them in this task, this review explored the association between functional impairments and work-related outcomes in breast cancer survivors. Methods Publications from January 2000-March 2016 were identified through five online databases (i.e. Pubmed, EMBASE, PsycINFO, CINAHL and the Cochrane Library). Quantitative and qualitative studies were included if they focused on functional impairments and work-related outcomes in breast cancer survivors. Two reviewers independently selected studies, extracted data and performed quality assessment. Results The search identified 998 studies, of which 20 studies met eligibility criteria. Impairments in physical functioning negatively affected return to work (RTW) and work ability in quantitative and qualitative studies. Studies measuring cognitive functioning with tests found no association with work-related outcomes, whereas the results of studies using self-reported measures were ambiguous. Social functioning was less commonly investigated and findings differed across work-related outcomes. Emotional functioning was not associated with work-related outcomes in quantitative studies, while in qualitative studies feelings such as insecurity were described as influencing RTW. Conclusions Functional impairments can severely hamper work participation in breast cancer survivors. This provides important opportunities for occupational health professionals to enhance RTW in breast cancer survivors, such as adequately addressing illness perceptions and work expectations. Ongoing research is warranted to aid occupational health professionals in providing effective vocational guidance and improve work-related outcomes in breast cancer survivors.

Comparing the effect of the subcategories of atypical antipsychotic medications on cognition in schizophrenia using a meta-analytic approach

OBJECTIVES

The aim of this study was to compare the two most commonly prescribed classes of atypical antipsychotic medications (i.e., -pines and -dones) with regard to their effects on cognition in patients with schizophrenia.

DATA SOURCES

Ovid Technologies web-based software was used to search the Medline and PsycINFO computerized databases to identify articles that met the inclusion criteria.

REVIEW METHODS

The search was limited to papers published after 1990, written in English, employing human subjects, using atypical antipsychotics, using a within-subjects design or control group of patients with schizophrenia for comparisons, using participants aged from 18-65, and employing standardized neuropsychological measures.

RESULTS

A total of 996 eligible studies were identified, and of these 19 were finally analyzed. Nine domains of cognitive functioning were assessed. The two groups of agents produced equivalent overall effects (-dones = .254 versus -pines = .202). The -pines were found to improve the domains of attention/working memory, executive functioning, fluency, nonverbal memory, processing speed, and verbal memory, each with a significant, small effect size. The -dones were found to improve attention/working memory, executive functioning, motor function, nonverbal memory, processing speed, and verbal memory, each with a significant, small effect size. Failsafe N was robust for all of the domains for the -pines, but only for the verbal memory domain for the -dones, suggesting that the significant findings for the other domains with the -dones are more tenuous.

CONCLUSION

The results indicate that the agents were largely equivalent and that there was no clear evidence that the pattern of cognitive effects differed as a result of the agent applied. The effects themselves, while statistically significant, were small, indicating that some or all of the differences may be attributable to practice effects on the instruments employed.

Cancer-related cognitive impairment in breast cancer survivors: An examination of conceptual and statistical cognitive domains using principal component analysis

There is a great deal of variability in the composition of neuropsychological test batteries used in the assessment of cancerrelated cognitive impairment (CRCI). Not only the development of a gold standard approach for CRCI assessment would allow for easier identification of women suffering from CRCI but it would also promote optimal care for survivors. As a first step towards the development of a valid and reliable unified test battery, the objective of this study was to verify whether the theoretical domains commonly used in CRCI assessment are statistically supported, before and after breast cancer treatment. Principal component analyses (PCA) were performed on the results from 23 neuropsychological tests grouped into eight conceptual domains. For baseline data, the Kaiser-Meyer-Olkin was .82 and Bartlett's X2(253, N=95) = 949.48, P<0.001. A five-component solution explained 60.94% of the common variance. For the post-treatment data, the Kaiser-Meyer-Olkin was .83 and Bartlett's X2(253, N=95) = 1007.21, P<0.001 and a five component solution explained 62.03% of the common variance. Although a visual comparison of the theoretical model with those determined via PCA indicated important overlap between conceptual domains and statistical components, significant dissimilarities were also observed.

Blood-based biomarkers of cancer-related cognitive impairment in non-central nervous system cancer: protocol for a scoping review

INTRODUCTION

Cancer-related cognitive impairment (CRCI) can have detrimental effects on quality of life, even among patients with non-central nervous system (CNS) cancers. Several studies have been conducted to explore different markers associated with CRCI to understand its pathobiology. It is proposed that the underlying mechanisms of CRCI are related to a cascade of physiological adaptive events in response to cancer and/or treatment. Hence, peripheral blood would be a logical source to observe and identify these physiological events. This paper outlines the protocol for a scoping review being conducted to summarise the extant literature regarding blood-based biomarkers of CRCI among patients with non-CNS cancer.

METHODS/ANALYSIS

Methods will be informed by the updated guidelines of Arksey and O'Malley. The systematic search for literature will include electronic databases, handsearching of key journals and reference lists, forward citation tracking and consultation with content experts. Study selection will be confirmed by duplicate review and calculation of inter-rater reliability. Data to be charted will include study design, sample size, cancer and treatment characteristics, demographic characteristics, cognitive variable/s and biomarkers assessed, associations between cognitive functioning and biomarkers (including statistics used), and rigour in biomarker sample collection and processing. Results will be presented through: (1) a descriptive numerical summary of studies, including a flow diagram based on the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement, (2) a list of blood-based biomarkers associated with CRCI and (3) a narrative overview developed through collaboration among the research team and consultation with content experts.

DISSEMINATION

The findings of this review will highlight current directions and gaps in the current body of evidence that may lead to improved rigour in future CRCI investigations. The dissemination of this work will be facilitated through the involvement of clinicians and researchers on the research team, an external consultation process and the presentation of the results through scholarly publication and presentation.

Association of Neurocognitive Deficits With Radiotherapy or Chemoradiotherapy for Patients With Head and Neck Cancer

Importance

Neurocognitive deficits (NCD) have been observed in noncentral nervous system cancers, yet short- and long-term neurocognitive data on patients treated for head and neck cancer (HNC) are lacking.

Objective

To assess objective neurocognitive function before and after definitive radiation therapy for HNC.

Design, Setting, and Participants

In a prospective, longitudinal study, neurocognitive function and self-reported symptoms were assessed in 80 patients with histologically proven HNC requiring definitive chemoradiotherapy or radiotherapy and in 40 healthy controls 4 times (baseline, 6, 12, and 24 months after baseline) prior to commencing treatment at Princess Margaret Cancer Centre, Toronto, Canada.

Main Outcomes and Measures

Neurocognitive test scores were converted to age-corrected z scores (mean, 0; standard deviation, 1) and reported as mean scores, standardized regression-based scores, and frequencies of impairments in intellectual capacity, concentration, memory, executive function, processing speed, and motor dexterity. Multivariable analysis was used to identify factors associated with NCD 2 years after treatment.

Results

Eighty patients and 40 healthy controls enrolled. Analyses revealed significant differences between patient and control mean performance in some domains, with patient deficits increasing over time: intellectual capacity (Cohen d, effect sizes [95% CIs] of -0.46 [-0.64 to 0.30], -0.51 [-0.72 to -0.30], and -0.70 [-0.92 to -0.49] for time points 6, 12, and 24 months, respectively); concentration/short-term attention span (-0.19 [-0.37 to 0.00], -0.38 [-0.55 to -0.21], -0.54 [-0.71 to -0.37]); verbal memory (-0.16 [-0.33 to 0.02], -0.38 [-0.64 to -0.12], -0.53 [-0.74 to -0.32]); executive function (-0.14 [-0.27 to 0.00], -0.34 [-0.52 to -0.16], -0.43 [-0.64 to -0.22]), and global cognitive function composite (-0.38 [-0.55 to -0.22], -0.75 [-0.92 to -0.58], -1.06 [-1.26 to -0.86]). There was an increased rate of impaired global neurocognitive functioning among patients (38%) at 24 months compared with controls (0%). Neurocognitive deficits were not associated with baseline cytokines.

Conclusions and Relevance

Head and neck cancer survivors have neurocognitive sequelae up to 2 years after definitive chemoradiotherapy or radiation treatment. Patients and health care teams should know about such potential risks. Further research is warranted in search of strategies to avoid, reduce, and compensate for declines.

Smartphone-Enabled Health Coaching Intervention (iMOVE) to Promote Long-Term Maintenance of Physical Activity in Breast Cancer Survivors: Protocol for a Feasibility Pilot Randomized Controlled Trial

Background

Although physical activity has been shown to contribute to long-term disease control and health in breast cancer survivors, a majority of breast cancer survivors do not meet physical activity guidelines. Past research has focused on promoting physical activity components for short-term breast cancer survivor benefits, but insufficient attention has been devoted to long-term outcomes and sustained exercise adherence. We are assessing a health coach intervention (iMOVE) that uses mobile technology to increase and sustain physical activity maintenance in initially inactive breast cancer survivors.

Objective

This pilot randomized controlled trial (RCT) is an initial step in evaluating the iMOVE intervention and will inform development of a full-scale pragmatic RCT.

Methods

We will enroll 107 physically inactive breast cancer survivors and randomly assign them to intervention or control groups at the University Health Network, a tertiary cancer care center in Toronto, Canada. Participants will be women (age 18 to 74 years) stratified by age (55 years and older/younger than 55 years) and adjuvant hormone therapy (AHT) exposure (AHT vs no AHT) following breast cancer treatment with no metastases or recurrence who report less than 60 minutes of preplanned physical activity per week. Both intervention and control groups receive the 12-week physical activity program with weekly group sessions and an individualized, progressive, home-based exercise program. The intervention group will additionally receive (1) 10 telephone-based health coaching sessions, (2) smartphone with data plan, if needed, (3) supportive health tracking software (Connected Wellness, NexJ Health Inc), and (4) a wearable step-counting device linked to a smartphone program.

Results

We will be assessing recruitment rates; acceptability reflected in selective, semistructured interviews; and enrollment, retention, and adherence quantitative intervention markers as pilot outcome measures. The primary clinical outcome will be directly measured peak oxygen consumption. Secondary clinical outcomes include health-related quality of life and anthropometric measures. All outcome measures are administered at baseline, after exercise program (month 3), and 6 months after program (month 9).

Conclusions

This pilot RCT will inform full-scale RCT planning. We will assess pilot procedures and interventions and collect preliminary effect estimates.

Trial Registration

ClinicalTrials.gov NCT02620735; https://clinicaltrials.gov/ct2/show/NCT02620735 (Archived by WebCite at https://clinicaltrials.gov/ct2/show/NCT02620735)

A novel preventive therapy for paclitaxel-induced cognitive deficits: preclinical evidence from C57BL/6 mice

Chemotherapy-induced central nervous system (CNS) neurotoxicity presents an unmet medical need. Patients often report a cognitive decline in temporal correlation to chemotherapy, particularly for hippocampus-dependent verbal and visuo-spatial abilities. We treated adult C57Bl/6 mice with 12 × 20 mg kg^-1 paclitaxel (PTX), mimicking clinical conditions of dose-dense chemotherapy, followed by a pulse of bromodesoxyuridine (BrdU) to label dividing cells. In this model, mice developed visuo-spatial memory impairments, and we measured peak PTX concentrations in the hippocampus of 230 nm l^-1, which was sevenfold higher compared with the neocortex. Histologic analysis revealed a reduced hippocampal cell proliferation. In vitro, we observed severe toxicity in slowly proliferating neural stem cells (NSC) as well as human neuronal progenitor cells after 2 h exposure to low nanomolar concentrations of PTX. In comparison, mature post-mitotic hippocampal neurons and cell lines of malignant cells were less vulnerable. In PTX-treated NSC, we observed an increase of intracellular calcium levels, as well as an increased activity of calpain- and caspase 3/7, suggesting a calcium-dependent mechanism. This cell death pathway could be specifically inhibited with lithium, but not glycogen synthase kinase 3 inhibitors, which protected NSC in vitro. In vivo, preemptive treatment of mice with lithium prevented PTX-induced memory deficits and abnormal adult hippocampal neurogenesis. In summary, we identified a molecular pathomechanism, which invokes PTX-induced cytotoxicity in NSC independent of cell cycle status. This pathway could be pharmacologically inhibited with lithium without impairing paclitaxel's tubulin-dependent cytostatic mode of action, enabling a potential translational clinical approach.

Late effects of blood and marrow transplantation

Hematopoietic cell transplantation is a curative treatment for a variety of hematologic diseases. Advances in transplantation technology have reduced early transplant-related mortality and expanded application of transplantation to older patients and to a wider variety of diseases. Management of late effects after transplantation is increasingly important for a growing number of long-term survivors that is estimated to be half a million worldwide. Many studies have shown that transplant survivors suffer from significant late effects that adversely affect morbidity, mortality, working status and quality of life. Late effects include diseases of the cardiovascular, pulmonary, and endocrine systems, dysfunction of the thyroid gland, gonads, liver and kidneys, infertility, iron overload, bone diseases, infection, solid cancer, and neuropsychological effects. The leading causes of late mortality include recurrent malignancy, lung diseases, infection, secondary cancers and chronic graft-versus-host disease. The aim of this review is to facilitate better care of adult transplant survivors by summarizing accumulated evidence, new insights, and practical information about individual late effects. Further research is needed to understand the biology of late effects allowing better prevention and treatment strategies to be developed.

Systemic therapies and cognitive impairment for breast cancer: an overview of the current literature

Both endocrine and chemotherapy can be utilized for breast cancer patients' management, in multiple setting (i.e., primary systemic therapy, adjuvant, metastatic treatment). Health-related quality of life in breast cancer survivors can be significantly influenced by cognitive impairment, which has been related in several previously reported experiences to systemic therapies administration. However, although the growing body of literature, the impact of both chemo- and endocrine therapy on cognitive function is currently unclear, due to many confounding factors (i.e., multiple therapies, duration of therapy, comorbidity, age). The aim of the present review is to present an overview of the current literature concerning the possible influence of endocrine and systemic therapy on breast cancer patients' cognitive impairment.

Review paper. Chemobrain in patients suffering from cancer based on the example of multiple myeloma

Introduction: The incidence rate of cancers emphasizes the necessity to investigate not only patients’ somatic ailments but also their psychosocial functioning as well as the need to raise the quality standards of cancer patients. The improvement of the quality of life is one of the major challenges of psycho-oncology, which is the science created in the interface of two disciplines: psychology and medicine.

One of the important aspects of psycho-oncologists’ activity is the minimization of negative side-effects related to treatment, such as changes in patients’ cognitive functioning resulting from anti-cancer treatment.

Objective: The aim of this work is to provide the reader with the knowledge concerning the phenomenon of chemobrain in a very special group of patients with hemato-oncologic tumour. Few researches related to this topic have confirmed the occurrence of cognitive deficits resulting from the cancer process, taken cytotoxic drugs, other forms of anti-cancer therapy and the activeness of biochemical compounds in patients with multiple myeloma.

Methods: The author has done a literary review concerning the topic under study using the Google Scholar and EBSCO databases. The main part of this work consists of references to Polish and English research literature published after 2000. The review includes also classic works from the eighties and nineties of the 20th century.

Results: The present work has been divided into several sections. The part devoted to explanation of the term chemobrain describes the evolution of its definition over the years. The second section - ‘Heterogeneity of the phenomenon - causes’ - underlines the influence of biochemical etiological factors, such as the impact of the activity of proinflammatory cytokines on the cognitive state of the patients suffering from tumour. Next part - ‘Chemobrain and multiple myeloma’ is devoted to the clinical characteristics of this cancer and to the descriptions of the selected methods of chemotherapy. The review of researches concerning the deteriorated cognitive functioning of patients with multiple myeloma in relation to the probable aetiology of this disease has been also presented.

Conclusions: The review of Polish and English literature concerning the functioning of memory and attention processes in the patients suffering from multiple myeloma can serve as an inspiration for a search for objective biochemical factors conditioning the deterioration of cognitive processes of the patients undergoing anti-cancer treatment.