Impairment In Cancer Survivors Research Articles

Funktionelle Beeinträchtigungen bei Krebsüberlebenden

Funktionelle Beeinträchtigungen bei Krebsüberlebenden

EDA2R reflects the acute brain response to cranial irradiation in liquid biopsies.

Cranial radiotherapy is standard of care for high-grade brain tumors and metastases; however, it induces debilitating neurocognitive impairments in cancer survivors, especially children. As the numbers of pediatric brain cancer survivors continue improving, the numbers of individuals developing life-long neurocognitive sequalae are consequently expected to rise. Yet, there are no established biomarkers estimating the degree of the irradiation-induced brain injury at completion of radiotherapy to predict the severity of the expected neurocognitive complications. We aimed to identify sensitive biomarkers associated with brain response to irradiation that can be measured in easily accessible clinical materials, such as liquid biopsies. Juvenile mice were subjected to cranial irradiation with 0.5, 1, 2, 4, and 8 Gy. Cerebrospinal fluid (CSF), plasma, and brains were collected at acute, subacute, and subchronic phases after irradiation, and processed for proteomic screens, and molecular and histological analyses. We found that the levels of ectodysplasin A2 receptor (EDA2R), member of tumor necrosis factor receptor superfamily, increased significantly in the CSF after cranial irradiation, even at lower irradiation doses. The levels of EDA2R were increased globally in the brain acutely after irradiation and decreased over time. EDA2R was predominantly expressed by neurons, and the temporal dynamics of EDA2R in the brain was reflected in the plasma samples. We propose EDA2R as a promising potential biomarker reflecting irradiation-induced brain injury in liquid biopsies. The levels of EDA2R upon completion of radiotherapy may aid in predicting the severity of IR-induced neurocognitive sequalae at a very early stage after treatment.

Cancer related cognitive impairment: a downside of cancer treatment.

Cancer treatment is associated with long lasting cognitive impairment in cancer survivors. This cognitive impairment is often termed cancer related cognitive impairment (CRCI). Cancer survivors treated for tumors outside the central nervous system are increasingly diagnosed with CRCI. The development of strategies to mitigate the negative effects of cancer treatment on the brain are crucial. Although neuroimaging research has proposed several candidate mechanisms, the pathogenic underpinnings of CRCI remain uncertain. As such, preventative and treatment strategies have not been identified. To fill these gaps, animal models play a vital role in isolating underlying contributing mechanisms that promote CRCI and in testing new therapeutic approaches.

Doxorubicin impairs cognitive function by upregulating AMPAR and NMDAR subunit expression and increasing neuroinflammation, oxidative stress, and apoptosis in the brain

Introduction: The anticancer drug doxorubicin (DOX) is used for various malignancies. However, it also causes cognitive impairment in cancer survivors. In order to determine the mechanisms underlying the acute effects of DOX, we assessed the mRNA and protein expression of glutamate receptors and proteins involved in cognitive function and apoptosis.Methods: Fear-conditioning memory tests were performed in rats after a single intraperitoneal injection of DOX (25 mg/kg) to evaluate short-term memory function. Rat brain samples were collected, and GluA1 mRNA and protein expression; NR2A and NR2B mRNA expression; and COX-2, NF-kB, TNF-α, and MDA, Bax, and caspase-3 levels were assessed via reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assays.Results: We observed a decreased number of entries in Y-maze, decreased exploration time to the novel object in the novel object recognition (NOR), and decreased freezing time in the fear-conditioning memory tests in DOX-treated rats relative to those in control rats, demonstrating cognitive impairment. GluA1, NR2B, and NR2A expression and MDA, NF-κB, Bax, COX-2, TNF-α, and caspase-3 levels in the brain were significantly elevated in DOX-treated rats.Conclusion: DOX induced cognitive impairment in the rats via neuronal toxicity by upregulating AMPAR and NMDAR expression and increasing neuroinflammation, oxidative stress, and apoptosis in the brain.

Neurocognitive Impairment in Non-Central Nervous System Cancer Survivors

Abstract: Cancer and its treatments entail a profound inflammatory response of the central nervous system (CNS). This intense neurotoxic process can lead to significant neurocognitive impairment even in non-CNS cancers. Few studies have examined this domain, and data available is based on limited designs using neuropsychological assessments comprising self-report or traditional testing batteries that capture basic response data. Here, we leverage cognitive electrophysiology, specifically Event-Related Potentials (ERPs), to examine and delineate neurocognitive impairments in non-CNS cancer survivors. Eleven survivors, who were on average 4.6 years in remission from head and neck cancer and 10 matched healthy controls underwent standardized cognitive and emotional “Go-Nogo” paradigms concomitant to EEG recording. Significant differences in amplitude morphology in the very early ERP components (C1, N1, P1) and middle ERP component (N2), were apparent between non-CNS cancer survivors and controls. Later ERP components (P3, N4) did not show amplitude differences. Non-CNS cancer survivors yielded faster latencies in the early components for pain-related stimuli during the emotional paradigm, albeit tended to yield slower ERP latencies overall across both experiments. These findings suggest that early gating and inhibitory control are dysregulated in non-CNS cancer survivors, which can impact executive functioning and cognitive processing involved in everyday activities for many years post-treatment. The findings do not fully align with ERP morphologies associated with neurocognitive impairment in degenerative conditions (such as dementia and Alzheimer’s disease), affecting later-stage ERP components. Our initial results suggest that (1) cognitive impairments in cancer survivors do not follow a degenerative trajectory, (2) rather are in line with “lesion” related damage (such as stroke, epilepsy), and as such, (3) have the potential for treatments involving neurocognitive plasticity.

Cancer survivors post-chemotherapy exhibit unimpaired short-latency stretch reflexes in the proximal upper extremity.

Oxaliplatin (OX) chemotherapy can lead to long-term sensorimotor impairments in cancer survivors. The impairments are often thought to be caused by OX-induced progressive degeneration of sensory afferents known as length-dependent dying-back sensory neuropathy. However, recent preclinical work has identified functional defects in the encoding of muscle proprioceptors and in motoneuron firing. These functional defects in the proprioceptive sensorimotor circuitry could readily impair muscle stretch reflexes, a fundamental building block of motor coordination. Given that muscle proprioceptors are distributed throughout skeletal muscle, defects in stretch reflexes could be widespread, including in the proximal region where dying-back sensory neuropathy is less prominent. All previous investigations on chemotherapy-related reflex changes focused on distal joints, leading to results that could be influenced by dying-back sensory neuropathy rather than more specific changes to sensorimotor circuitry. Our study extends this earlier work by quantifying stretch reflexes in the shoulder muscles in 16 cancer survivors and 16 healthy controls. Conduction studies of the sensory nerves in hand were completed to detect distal sensory neuropathy. We found no significant differences in the short-latency stretch reflexes (amplitude and latency) of the shoulder muscles between cancer survivors and healthy controls, contrasting with the expected differences based on the preclinical work. Our results may be linked to differences between the human and preclinical testing paradigms including, among many possibilities, differences in the tested limb or species. Determining the source of these differences will be important for developing a complete picture of how OX chemotherapy contributes to long-term sensorimotor impairments.NEW & NOTEWORTHY Our results showed that cancer survivors after oxaliplatin (OX) treatment exhibited stretch reflexes that were comparable with age-matched healthy individuals in the proximal upper limb. The lack of OX effect might be linked to differences between the clinical and preclinical testing paradigms. These findings refine our expectations derived from the preclinical study and guide future assessments of OX effects that may have been insensitive to our measurement techniques.

Association of markers of inflammation on attention and neurobehavioral outcomes in survivors of childhood acute lymphoblastic leukemia.

Survivors of childhood acute lymphoblastic leukemia (ALL) are at-risk of developing cognitive impairment and neurobehavioral symptoms. Inflammation induced by a compromised health status during cancer survivorship is proposed as a pathophysiological mechanism underlying cognitive impairment in cancer survivors. To evaluate the associations of biomarkers of inflammation with attention and neurobehavioral outcomes in survivors of childhood ALL, and to identify clinical factors associated with biomarkers of inflammation in this cohort. We recruited patients who were diagnosed with ALL at ≤ 18 years old and were currently ≥5 years post-cancer diagnosis. The study outcomes were attention (Conners Continuous Performance Test) and self-reported behavioral symptoms (Adult Self-Report [ASR] checklist). Using a commercial screening kit, survivors' plasma (5ml) was assayed for 17 cytokines/chemokine cell-signaling molecules that are associated with neurodegenerative diseases. The final panel of the targeted markers included interleukin (IL)-8, IL-13, interferon-gamma (IFN-γ), monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1β, and tumor necrosis factor-α. Biomarker levels were rank-ordered into tertiles based on the sample distribution. Multivariable general linear modeling was used to test for associations between biomarkers and study outcomes in the overall cohort and stratified by gender. This study included 102 survivors (55.9% males, mean[SD] age 26.2[5.9] years; 19.3[7.1] years post-diagnosis). Survivors within top tertiles of IFN-γ (Estimate =6.74, SE=2.26; P=0.0037) and IL-13 (Estimate =5.10, SE=2.27; P=0.027) demonstrated more inattentiveness. Adjusting for age, gender and treatment, more self-reported thought (Estimate=3.53, SE=1.78; P=0.050) and internalizing problems (Estimate =6.52, SE=2.91; P=0.027) correlated with higher IL-8. Higher levels of IL-13 (RR = 4.58, 95% CI: 1.01-11.10) and TNF-α (RR = 1.44, 95% CI: 1.03-4.07) were observed in survivors had developed chronic health conditions (n=26, 25.5%). The stratified analysis showed that association of IFN-γ with attention was stronger in male survivors than in female survivors. Inflammation due to cancer-related late effects may potentially be mechanistic mediators of neurobehavioral problems in pediatric ALL survivors. Markers of inflammation can potentially be applied to assess or monitor the effectiveness of interventions, particularly behavioral interventions, in improving cognitive outcomes in survivors. Future work includes understanding the underlying gender-specific pathophysiology behind functional outcomes in the population.

Radiation-Induced Brain Injury: Age Dependency of Neurocognitive Dysfunction Following Radiotherapy.

Cranial radiotherapy is a known risk factor for neurocognitive impairment in cancer survivors. Although radiation-induced cognitive dysfunction is observed in patients of all ages, children seem to be more vulnerable than adults to suffering age-related deficits in neurocognitive skills. So far, the underlying mechanisms by which IR negatively influences brain functions as well as the reasons for the profound age dependency are still insufficiently known. We performed a comprehensive Pubmed-based literature search to identify original research articles that reported on age dependency of neurocognitive dysfunction following cranial IR exposure. Numerous clinical trials in childhood cancer survivors indicate that the severity of radiation-induced cognitive dysfunction is clearly dependent on age at IR exposure. These clinical findings were related to the current state of experimental research providing important insights into the age dependency of radiation-induced brain injury and the development of neurocognitive impairment. Research in pre-clinical rodent models demonstrates age-dependent effects of IR exposure on hippocampal neurogenesis, radiation-induced neurovascular damage and neuroinflammation.

The Experience of Peripheral Neuropathy Symptoms in Breast Cancer Survivors With Diabetes.

Diabetes (type 2) is a risk factor for developing peripheral neuropathy (PN) symptoms in breast cancer survivors (BCS). Because PN symptoms are associated with deficits in physical functioning and quality of life, more information is needed about the effects of PN symptoms on the lives of BCS with diabetes. The aim of this study was to describe the experiences of PN among BCS with diabetes from their own perspectives. This substudy is part of a larger investigation examining factors associated with cancer-related cognitive impairment in cancer survivors. Female early-stage (stage I-III) BCS with diabetes and PN symptoms were eligible to participate. A qualitative descriptive approach using purposive sampling and semistructured interviews was used. Participant narratives were summarized using standard content analytic techniques. Eleven BCS with diabetes and PN symptoms were interviewed. Participants described PN symptoms that were varied, were often persistent, and had troublesome effects on their physical functioning and quality of life. Participants used a variety of self-management strategies and prescription and over-the-counter medications to manage their PN symptoms. Some said that having both cancer and diabetes exacerbated the PN symptoms and complicated symptom management. Peripheral neuropathy symptoms can have a profound effect on the lives of BCS with diabetes and should be addressed by healthcare providers. Clinical care for this population should include ongoing assessment of PN symptoms, conversations about the effects of these symptoms on everyday life, evidence-based treatment for the symptoms, and support for symptom self-management.

A scoping review of cognitive assessment tools and domains for chemotherapy-induced cognitive impairments in cancer survivors.

Cancer survivors suffer from specific symptoms known as chemotherapy-induced cognitive impairments (CICIs). CICIs are difficult to capture with existing assessments such as the brief screening test for dementia. Although recommended neuropsychological tests (NPTs) exist, international consensus and shared cognitive domains of assessment tools are unknown. The aim of this scoping review was as follows: (1) to identify studies that assess CICIs in cancer survivors; (2) to identify shared cognitive assessment tools and domains by mapping the domains reported in studies using the International Classification of Functioning, Disability and Health (ICF) framework. The study followed the recommendations made by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. We searched the following three databases through October 2021: PubMed, CINAHL, and Web of Science. Prospective longitudinal or cross-sectional studies were selected to determine CICI-specific assessment tools for adult cancer survivors. Sixty-four prospective studies (36 longitudinal studies and 28 cross-sectional studies) were included after checking for eligibility. The NPTs were divided into seven main cognitive domains. The specific mental functions were often used in the order of memory, attention, higher-level cognitive functions, and psychomotor functions. Perceptual functions were used less frequently. In some ICF domains, shared NPTs were not clearly identified. In some different domains, the same NPTs were used, such as the trail making test and the verbal fluency test. When the association between the publishing year and the amount of NPT use was examined, it was found that the amount of tool use tended to decline over the publication years. The Functional Assessment of Cancer Therapy-Cognitive function (FACT-Cog) was a shared consensus tool among the patient-reported outcomes (PROs). Chemotherapy-induced cognitive impairments are currently gaining interest. Shared ICF domains such as memory and attention were identified for NPTs. There was a gap between the publicly recommended tools and the tools actually used in the studies. For PROs, a clearly shared tool, FACT-Cog, was identified. Mapping the domains reported in studies using the ICF can help in the process of reviewing consensus on which NPTs may be used to target cognitive domains. https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000053710, identifier UMIN000047104.

Exploratory study on the effectiveness of integrative neurocognitive remediation therapy (iNCRT) for cancer survivors

IntroductionCancer survivors frequently report suffering from neurocognitive impairment, that persists after physical recovery from their disease. Cognitive impairment is associated with important emotional disturbances, socio-professional consequences and diminished quality of life.ObjectivesThis observational study aims to assess the effectives of an integrative neurocognitive remediation therapy (iNRCT), offered as a 12-week program (1day/week), organized within our Cognitive Remediation Clinic. The iNCRT combines personalized computerized cognitive training and neurocognitive strategy training, with group sessions of physical exercise, mindfulness, and cognitive behavior therapy (CBT).MethodsThe assessment before and after NCRT includes neuropsychological testing (10 subtests), assessment of daily functioning and subjective neurocognitive function (NCF).ResultsOut of 16 eligible cancer survivors, 12 patients were recruited and 11 completed the iNCRT; median age 53 years [range, 41-71]; 3 patients had a prior history of a central nervous system tumor, 5 patients of breast cancer, 2 patients of stage-IV melanoma, and 1 patient of gastric cancer. After iNCRT subjective NCF did not improve significantly (p=0.13) according to the Cognitive Failure Questionnaire. However neuropsychological assessment revealed an improvement on ≥ 1 impaired subtest in all patients; 6 patients improved on ≥ 4 impaired subtests. Improvement was most prominent in long-term verbal and visual memory, working memory and executive function. All patients reported a clinical benefit in their daily function after completion of iNCRT.ConclusionsOur iNRCT, which combines personalized neurocognitive training with physical exercise, mindfulness and CBT can be an effective therapeutic model for treating neurocognitive impairment in cancer survivors, with a clinically relevant impact on their daily function.DisclosureNo significant relationships.

Characterising pragmatic exercise interventions to reduce cognitive impairment in cancer survivors: A scoping review protocol

Objective: The objective of this scoping review is to identify the characteristics of pragmatic exercise interventions aimed to reduce cognitive impairment in cancer survivors, and their effectiveness in reducing this impairment and maintaining high adherence.Introduction: Cognitive impairment (CI) is a particularly troublesome side-effect of cancer treatment that has been suggested to decrease following exercise interventions. Most existing research consists of randomized control trials, which often lack external validity. Pragmatic interventions fill this gap. Some pragmatic trials that provide real-world evidence, however, struggle to maintain strong participant adherence. Thus, examining characteristics of pragmatic interventions with high levels of adherence may be beneficial in improving overall adherence in future pragmatic trials on this topic.Inclusion criteria: This review will examine literature with cancer survivors who are partaking in pragmatic exercise programs. Specifically, literature exploring the effects of pragmatic exercise interventions in decreasing cancer survivors’ CI will be examined, with no limits to intervention mode, frequency, or duration. “Cancer survivor” will be defined as any individual with a cancer diagnosis, at any point along the survivorship continuum.Methods: A comprehensive search strategy was developed in accordance with JBI methodology to retrieve relevant sources. Databases to be reviewed from inception to present will include CINAHL, MEDLINE, EMBASE, SPORTDiscus, Scopus, and PsychInfo. Two independent screeners will examine titles and abstracts as well as full texts of relevant sources. The results of the search and the study inclusion process will be reported in full in a PRISMA-ScR flow diagram. The results will be presented narratively, using appropriate tables and figures.

Effects of CMF and MET on glutamate and dopamine levels in the brain, and their impact on cognitive function.

Chemotherapy can cause cognitive impairment in cancer survivors. CMF, the combination of cyclophosphamide (CYP), methotrexate (MTX), and 5-fluorouracil (5-FU), is employed for the treatment of several types of cancers, such as metastatic breast cancer. Metformin (MET) is an antidiabetic medication used to treat type 2 diabetes that can reportedly alleviate some toxic effects. In the current study, we investigated the ability of MET to alleviate the effects of CMF in neuronal toxicity. Rats were treated with two doses of CMF (intraperitoneal injection) and MET (in the daily drinking water). Rats were subjected to fear conditioning memory tests to evaluate memory function following treatment, and brain samples were collected and homogenized using neuronal lysis buffer for assessment of glutamate and dopamine levels by high-performance liquid chromatography (HPLC). Fear conditioning memory tests revealed a significant reduction in memory function in CMF and CMF+MET groups vs. controls, but no significant change in MET groups vs. controls was detected. Similarly, CMF and CMF+MET groups revealed a significant increase in glutamate and dopamine levels in the brain of MET, CMF, and MET+CMF groups vs. controls based on HPLC results. In addition, although glutamate and dopamine levels were increased, levels varied between groups, with highest levels in the CMF+MET group. Our results demonstrate that cognitive impairment in CMF and CMF+MET groups could result from increased glutamate and dopamine levels in the brain, leading to brain toxicity and failure of MET to alleviate the toxic effects of CMF.

Cancer survivors post-chemotherapy exhibit unique proprioceptive deficits in proximal limbs

BackgroundOxaliplatin (OX) chemotherapy for colorectal cancer is associated with adverse neurotoxic effects that can contribute to long-term sensorimotor impairments in cancer survivors. It is often thought that the sensorimotor impairments are dominated by OX-induced dying-back sensory neuropathy that primarily affects the distal regions of the limb. Recent preclinical studies have identified encoding dysfunction of muscle proprioceptors as an alternative mechanism. Unlike the dying-back sensory neuropathy affecting distal limbs, dysfunction of muscle proprioceptors could have more widespread effects. Most investigations of chemotherapy-induced sensorimotor impairments have considered only the effects of distal changes in sensory processing; none have evaluated proximal changes or their influence on function. Our study fills this gap by evaluating the functional use of proprioception in the shoulder and elbow joints of cancer survivors post OX chemotherapy. We implemented three multidirectional sensorimotor tasks: force matching, target reaching, and postural stability tasks to evaluate various aspects of proprioception and their use. Force and kinematic data of the sensorimotor tasks were collected in 13 cancer survivors treated with OX and 13 age-matched healthy controls.ResultsCancer survivors exhibited less accuracy and precision than an age-matched control group when they had to rely only on proprioceptive information to match force, even for forces that required only torques about the shoulder. There were also small differences in the ability to maintain arm posture but no significant differences in reaching. The force deficits in cancer survivors were significantly correlated with self-reported motor dysfunction.ConclusionsThese results suggest that cancer survivors post OX chemotherapy exhibit proximal proprioceptive deficits, and that the deficits in producing accurate and precise forces are larger than those for producing unloaded movements. Current clinical assessments of chemotherapy-related sensorimotor dysfunction are largely limited to distal symptoms. Our study suggests that we also need to consider changes in proximal function. Force matching tasks similar to those used here could provide a clinically meaningful approach to quantifying OX-related movement dysfunction during and after chemotherapy.

Elucidating the mechanism underlying cognitive dysfunction by investigating the effects of CMF and MET treatment on hippocampal neurons.

Chemotherapy causes long-term cognitive impairment in cancer survivors. A combination of cyclophosphamide (CYP), methotrexate (MTX), and 5-fluorouracil (5-FU) (i.e., CMF) is widely used for cancer treatment. Metformin (MET), an oral antidiabetic drug, confers protection against the adverse effects of chemotherapeutic agents, such as CYP. To elucidate the potential mechanism underlying cognitive dysfunction, we investigated the impact of CMF and MET treatment on the activities of mitochondrial respiratory chain complexes I and IV, as well as lipid peroxidation, in hippocampal neurons. Hippocampal neurons (H19-7) cells were treated for 24 h with MET (0.5 mM) alone; CYP (1 µM), MTX (0.5 µM), and 5-FU (1 µM); and MET (0.5 mM) + CYP (1 µM), MTX (0.5 mM), and 5-FU (1 µM). A 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide assay was performed to evaluate cell survival. Neurons were collected and homogenized in a neuronal lysis buffer to assess mitochondrial complexes (I and IV) activity and lipid peroxidation. Compared to the control, MET-treated cells showed no significant difference in survival rate; however, CMF- and CMF + MET-treated cells showed a significant reduction in survival rate. In addition, relative to the control, CMF- and CMF + MET-treated cells showed a reduction in mitochondrial complex I activity, whereas no significant changes were observed in mitochondrial complex IV activity. MET-treated cells showed no significant differences in lipid peroxidation, but CMF- and CMF + MET-treated cells showed a slight increase in lipid peroxidation. The reduction in the activity of mitochondrial complex I and a slight increase in lipid peroxidation levels may explain the cognitive impairment following CMF and MET treatments.

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

BackgroundCancer-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).MethodsIn 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.FindingsBetween 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.InterpretationThis 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.

Metformin effects on brain development following cranial irradiation in a mouse model.

Cranial radiation therapy (CRT) is a mainstay of treatment for malignant pediatric brain tumors and high-risk leukemia. Although CRT improves survival, it has been shown to disrupt normal brain development and result in cognitive impairments in cancer survivors. Animal studies suggest that there is potential to promote brain recovery after injury using metformin. Our aim was to evaluate whether metformin can restore brain volume outcomes in a mouse model of CRT. C57BL/6J mice were irradiated with a whole-brain radiation dose of 7 Gy during infancy. Two weeks of metformin treatment started either on the day of or 3 days after irradiation. In vivo magnetic resonance imaging was performed prior to irradiation and at 3 subsequent time points to evaluate the effects of radiation and metformin on brain development. Widespread volume loss in the irradiated brain appeared within 1 week of irradiation with limited subsequent recovery in volume outcomes. In many structures, metformin administration starting on the day of irradiation exacerbated radiation-induced injury, particularly in male mice. Metformin treatment starting 3 days after irradiation improved brain volume outcomes in subcortical regions, the olfactory bulbs, and structures of the brainstem and cerebellum. Our results show that metformin treatment has the potential to improve neuroanatomical outcomes after CRT. However, both timing of metformin administration and subject sex affect structure outcomes, and metformin may also be deleterious. Our results highlight important considerations in determining the potential benefits of metformin treatment after CRT and emphasize the need for caution in repurposing metformin in clinical studies.

Abstract 12919: Quantitative Assessment of Cardiovascular Autonomic Impairment in Cancer Survivors: A Single Center Experience

Background: Cardiovascular autonomic dysfunction in cancer survivors is poorly understood. Objectives: To better characterize the clinical characteristics and types of autonomic dysfunction in this population. Methods: A retrospective analysis of cancer survivors within an academic cardio-oncology program referred for suspected autonomic dysfunction was performed. Autonomic reflex testing of adrenergic, cardiovagal, and sudomotor function was done. Patients with pre-existing autonomic dysfunction prior to their cancer diagnosis were excluded. Results: Of approximately 282 patients in the UCLA Cardio-Oncology program, twenty-four patients met the inclusion criteria. Twenty-two had autonomic impairment on autonomic reflex testing. Eight patients were female, and the mean age at time of autonomic testing was 51.3 years. The average duration from cancer diagnosis to autonomic testing was 10.3 years. The reasons for referral included dizziness, tachycardia, palpitations, and syncope. The majority of patients (75%) had hematologic disorders. The most common chemotherapies administered were vinca alkaloids (54.2%), alkylating agents (66.7%), and anthracyclines (54.2%). Most patients received radiation to the thorax (66.7%) and neck (53.3%). Eleven patients had mild autonomic impairment, seven had moderate, and four had severe autonomic impairment. Dysfunction was commonly present in the sympathetic and parasympathetic branches, but most pronounced in the sympathetic system. The majority of patients were diagnosed with orthostatic hypotension (50%), inappropriate sinus tachycardia (20.8%), and postural orthostatic tachycardia syndrome (12.5%) and had subjective improvement with treatment. Conclusion: Cardiovascular autonomic dysfunction occurs in cancer survivors, and commonly affects both the sympathetic and parasympathetic systems. Symptom recognition in patients should prompt autonomic testing and treatment where appropriate.

Chemotherapy-induced grey matter abnormalities in cancer survivors: a voxel-wise neuroimaging meta-analysis.

Findings regarding chemotherapy-induced grey matter abnormalities are heterogeneous, and no meta-analysis has quantitatively assessed brain structural alterations in cancer survivors treated with chemotherapy. To investigate the grey matter abnormalities in non-CNS (central nervous system) cancer survivors treated with chemotherapy using Anisotropic Effect Size Signed Differential Mapping (AES-SDM) software. We identified studies published up to Sep 2018 that compared grey matter in non-CNS cancer survivors treated with chemotherapy (CT+, 10 data sets including 433 individuals) and cancer survivors not treated with chemotherapy (CT-, 7 data sets including 210 individuals) or healthy controls (HC, 3 data sets including 407 individuals) using whole-brain VBM. We used statistical maps from the studies included where available and reported peak coordinates otherwise. Compared with both CT- and HC, the CT + groups exhibited a reduced grey matter volume (GMV), mainly in the prefrontal and anterior cingulate cortex (ACC) and right fusiform gyrus (FG). A smaller GMV in the FG and prefrontal cortex were found in the CT + compared with the CT-groups and in the CT + groups with impaired cognition. GMV in two areas was positively associated with the time since chemotherapy. The present results suggest that non-CNS cancer survivors treated with chemotherapy exhibit grey matter abnormalities in the brain, especially in the prefrontal and ACC cortex. Grey matter volume changes after chemotherapy may contribute to cognitive impairments in cancer survivors that can be observed after chemotherapy.

Quantitative assessment of cardiovascular autonomic impairment in cancer survivors: a single center case series

BackgroundCardiovascular autonomic dysfunction in cancer survivors is poorly understood.ObjectivesTo better characterize the clinical characteristics and types of autonomic dysfunction in this population.MethodsA retrospective analysis of cancer survivors within an academic cardio-oncology program referred for suspected autonomic dysfunction was performed. Autonomic reflex testing of adrenergic, cardiovagal, and sudomotor function was done. Autonomic impairment was graded on severity based on the Composite Autonomic Severity Score system. Patients with pre-existing autonomic dysfunction prior to their cancer diagnosis were excluded.ResultsOf approximately 282 total patients in the UCLA Cardio-Oncology program, 24 were referred for suspected autonomic dysfunction and met the inclusion criteria. 22 had autonomic impairment on autonomic reflex testing. Eight patients were female, and the mean age at time of autonomic testing was 51.3 years. The average duration from cancer diagnosis to autonomic testing was 10.3 years. The reasons for referral included dizziness, tachycardia, palpitations, and syncope. The majority of patients (75%) had hematologic disorders. The most common chemotherapies administered were vinca alkaloids (54.2%), alkylating agents (66.7%), and anthracyclines (54.2%). Most patients received radiation to the thorax (66.7%) and neck (53.3%). Eleven patients had mild autonomic impairment, 7 had moderate, and 4 had severe autonomic impairment. Dysfunction was commonly present in the sympathetic and parasympathetic branches, but most pronounced in the sympathetic system. The majority of patients were diagnosed with orthostatic hypotension (50%), inappropriate sinus tachycardia (20.8%), and postural orthostatic tachycardia syndrome (12.5%) and had subjective improvement with treatment.ConclusionCardiovascular autonomic dysfunction occurs in cancer survivors, and commonly affects both the sympathetic and parasympathetic systems. Symptom recognition in patients should prompt autonomic testing and treatment where appropriate.