Children with non-central nervous system tumors treated with platinum-based chemotherapy are at risk for hearing loss and cognitive impairments

Background

Childhood cancer survivors (CCS) with chemotherapy induced sensorineural hearing loss (SNHL) are at risk for neurocognitive impairments. The purpose of this study was to determine the relationship between SNHL and cognitive function among CCS.

Procedure

Inclusion: non-CNS solid tumor diagnosis; history of platinum chemotherapy (cisplatin and/or carboplatin); 8-17 years of age; off anti-cancer treatment for ≥6 months; and English speaking. Exclusion: history of intrathecal chemotherapy, cranial radiation, or baseline neurocognitive disorder. Participants completed the NIH Toolbox Cognition Battery at enrollment. T-tests were used to compare participants with normal hearing to those with hearing loss and the total sample with established Toolbox normative data (mean: 50; SD: 10).

Results

Fifty-seven individuals enrolled; 52 completed full cognitive testing. Participants were on average 12.2 years of age and 7.0 years since treatment completion. Twenty-one participants (40%) received cisplatin, 27 (52%) carboplatin, and 4 (8%) received both. Fifteen participants (29%) demonstrated SNHL based on the better ear. CCS, regardless of the presence or absence of SNHL, demonstrated significantly lower mean cognitive skills compared to the normative sample in attention, executive function, language- vocabulary and oral reading, processing speed, and fluid, crystallized and total composite scores (all p < 0.01). Participants with SNHL had significantly lower crystallized composite (vocabulary, oral reading) than those with normal hearing (41.9 vs. 47.2, p < 0.05, Cohen's d = 0.62).

Conclusions

CCS at risk for platinum induced hearing loss but without cranial radiation or intrathecal chemotherapy exposure demonstrate impaired cognitive skills and those with SNHL demonstrate lower crystallized composite scores.

Frontal and anterior temporal hypometabolism post chemoradiation in head and neck cancer: A real-world PET study

BACKGROUND AND PURPOSE

Adverse neurological effects after cancer therapy are common, but biomarkers to diagnose, monitor, or risk stratify patients are still not validated or used clinically. An accessible imaging method, such as fluorodeoxyglucose positron emission tomography (FDG PET) of the brain, could meet this gap and serve as a biomarker for functional brain changes. We utilized FDG PET to evaluate which brain regions are most susceptible to altered glucose metabolism after chemoradiation in patients with head and neck cancer (HNCa).

METHODS

Real-world FDG PET images were acquired as standard of care before and after chemoradiation for HNCa in 68 patients. Linear mixed-effects voxelwise models assessed changes after chemoradiation in cerebral glucose metabolism quantified with standardized uptake value ratio (SUVR), covarying for follow-up time and patient demographics.

RESULTS

Voxelwise analysis revealed two large clusters of decreased glucose metabolism in the medial frontal and polar temporal cortices following chemoradiation, with decreases of approximately 5% SUVR after therapy.

CONCLUSIONS

These findings provide evidence that standard chemoradiation for HNCa can lead to decreased neuronal glucose metabolism, contributing to literature emphasizing the vulnerability of the frontal and anterior temporal lobes, especially in HNCa, where these areas may be particularly vulnerable to indirect radiation-induced injury. FDG PET shows promise as a sensitive biomarker for assessing these changes.

Prevalence and associated factors of chemotherapy-related cognitive impairment in older breast cancer survivors

AIMS

To examine the prevalence and associated factors of chemotherapy-related cognitive impairment (CRCI) in older breast cancer survivors (BCS).

DESIGN

Systematic review.

DATA SOURCES

We searched EMBASE, PubMed, PsychInfo, CINAHL, Cochrance Library, Web of Science, CNKI and SinoMed, without language restrictions, for studies published from the establishment of the database to September 2022.

REVIEW METHODS

Two researchers independently examined the full texts, data extraction and quality assessment, and any discrepancies were resolved through discussion with a third reviewer. Quality of evidence was assessed using the Newcastle-Ottawa Scale and the Agency for Healthcare Research and Quality Scale.

RESULTS

The seven included studies showed that the estimated prevalence of CRCI in older BCS ranged from 18.6% to 27% on objective neuropsychological tests and from 7.6% to 49% on subjective cognitive assessments. The areas most affected were attention, memory, executive functioning and processing speed. CRCI was associated with 10 factors in six categories, including sociodemographic (e.g. age, education level), physiological (e.g. sleep disorders, fatigue and comorbidities), psychological (e.g. anxiety, depression), treatment modalities (e.g. chemotherapy cycles, chemotherapy regimens), genetic (e.g. APOE2, APOE4) and lifestyle factor (e.g. physical inactivity).

CONCLUSION

CRCI is multifactorial and has a relatively high prevalence. However, the results of subjective and objective cognitive examinations were inconsistent, possibly due to variations in tools used to evaluate different definitions of CRCI. Nevertheless, as there are few published studies of older BCS, this conclusion still require verification by well-designed studies in the future.

IMPACT

We found that the prevalence of CRCI in older adults is relatively high and multifactorial, providing evidence for further health care for this population.

NO PATIENT OR PUBLIC CONTRIBUTION

There was no patient or public involvement.

Cognitive impairments associated with chemotherapy in women with breast cancer: a meta-analysis and meta-regression

Chemotherapy is one of the most widely used treatments for breast cancer (BC). However, there is evidence of side effects like cognitive changes related to the chemotherapy treatment. The aim of the study was not only to summarize the existing evidence on the relationship between chemotherapy and cognitive performance in women with BC but also to identify additional consequences and aspects associated with these impairments. We conducted a systematic review with meta-analysis and meta-regression to present updated information on the matter. We retrieved data from the databases PubMed, Web of Science, PsycINFO, CINAHL, and Scopus. Twenty studies comprising over 2,500 women were examined and the results indicated that chemotherapy can compromise cognition in women with BC (-1.10 OR [95%CI: -1.81 to -0.74], P<0.01), with working memory (-0.49 OR [95%CI: -0.85 to -0.13], P=0.03) being the most affected among the domains. Furthermore, additional data indicated that cognitive impairment is most likely amid women with BC having a lower education level (Q=4.85, P=0.02). Our results suggested that chemotherapy affects cognitive functions in women with BC, and certain characteristics can worsen the deterioration. A comprehensive study of women with breast cancer and existing predictors contributes to optimized personal journeys, elevated life prospects, and advanced care that can also aid prognosis and therapeutic approaches.

Transcranial Magnetic Stimulation for the Treatment of Chemo Brain

This pilot feasibility study aimed to evaluate the effects of transcranial magnetic stimulation (TMS) on chemotherapy-related cognitive impairment (CRCI), and we report here on the first patient.

BACKGROUND

Deleterious cognitive changes due to chemotherapy or CRCI are commonly referred to as "chemo brain". With the increasing survival of cancer patients, this poorly understood and inadequately treated condition will likewise have an increasing toll on individuals and society. Since there is no approved treatment for chemo brain, we have initiated a therapeutic trial using transcranial magnetic stimulation (TMS), a non-invasive brain stimulation technique approved in many countries for the treatment of neurologic and psychiatric conditions like migraine and depression.

CASE PRESENTATION

A 58-year-old woman, diagnosed 7 years prior with left breast cancer, underwent partial mastectomy with sentinel lymph node biopsy. She then received four cycles of adjuvant chemotherapy followed by radiation therapy. Afterwards, she was on tamoxifen for 4 years and then switched to aromatase inhibitors. The patient's CRCI started during chemotherapy and severely impaired her quality of life for an additional two years. In the third year after chemotherapy, the CRCI partially cleared to stabilize to the level at the time of presentation for this trial. The patient continues to have memory difficulties and decreased concentration, which makes multi-tasking very difficult to impossible. She is reliant on memory aids at work and at home. The participant underwent 10 consecutive sessions of TMS during weekdays for 2 weeks. Stimulation was directed to the left dorsolateral prefrontal cortex. After TMS, the participant significantly improved in memory function on neuropsychological testing. While she reported no subjective differences in concentration or memory, she did report an improvement in her sleep. Functional magnetic resonance imaging of the brain before and after TMS showed increased resting-state functional connectivity between the stimulation site and several brain regions. Remarkably, after 6 years of chemo brain and remaining in the same position at work due to her inability to concentrate and multi-task, she applied for and received a promotion 5-6 months after her TMS treatments.

CONCLUSIONS

This first patient in the phase 1 clinical trial testing of TMS for the treatment of "chemo brain" provided important lessons for feasibility and insights into mechanisms of potential benefit.

Cognitive function and breast cancer molecular subtype before and after chemotherapy

Chemotherapy-related cognitive impairment has been reported in patients with breast cancer and received growing attention due to increased survival rate. However, cognitive outcome according to pathological tumor features, especially human epidermal growth factor receptor (HER2) status, has not been clearly elucidated. Despite its potential link with cognitive status through neuroinflammatory response, existing research is sparse and limited to cross-sectional studies. In this observational cohort study, 52 breast cancer patients received a series of neuropsychological examinations before and after chemotherapy. Patients' performances were compared with normative data, and analyzed with Reliable Change Indices and mixed-model analysis of covariance. Results showed that there was a higher percentage of HER2+ patients than HER2- patients who showed defective attention and processing speed before chemotherapy, and that there were more patients with HER2+ status showing cognitive decline on tests of attention and executive functions following chemotherapy. Group-wise analyses confirmed the foregoing pattern and further revealed that patients with HER2+ status also tended to deteriorate more in verbal memory after chemotherapy. These findings indicate that HER2 overexpression may serve as prognostic factors that help explain the heterogeneous cognitive outcome in breast cancer survivors. Further studies are needed to replicate this finding and delineate the underlying mechanisms.

Interventions promoting cognitive function in patients experiencing cancer related cognitive impairment: A systematic review

OBJECTIVE

To examine the effect of interventions used to enhance cognitive function in patients experiencing cancer-related cognitive impairment.

METHODS

Studies including adults with a non-metastatic cancer who have received chemotherapy as part of their treatment and who have undergone interventions targeting cancer-related cognitive impairment were included. Studies involving patients with metastatic cancer and pre-existing cognitive deficits were excluded. Academic Search Complete, CINAHL Plus with full text, MEDLINE, Education Full Text, PsycARTICLES, PsycINFO, and ERIC were searched for studies published between January 2011 and September 2022. Data extraction and quality appraisal were conducted by two authors and cross-checked by the review team. Quality appraisal was conducted using 12 items from the Mixed Methods Appraisal Tool. Findings were presented narratively without meta-analysis.

RESULTS

Thirty-one studies were included. Interventions were categorised as integrative/complementary, cognitive behavioural therapy and compensatory strategies, exercise, psychoeducational/psychosocial, brain-training, and pharmacological. Over 100 instruments were identified, including the Functional Assessment of Cancer Therapy-Cognitive, Trail Making Tests-A and B, and instruments measuring secondary outcomes, including depression. Instruments often measured attention and concentration, language, memory, executive function, and/or patient-reported outcomes. Improvements were reported, with most studies measuring some or various aspects of cognitive functioning and very few studies measuring all domains of cognitive functioning, making it difficult to draw definitive conclusions about effectiveness.

CONCLUSIONS

Various interventions are available to treat cancer-related cognitive impairment. Outcome measurement was inconsistent and future research should prioritise using standardised measures. Current evidence, whilst not being definitive, suggests that certain interventions show greater promise than others, including cognitive behavioural therapy and brain training.

Neurological Complications of Conventional and Novel Anticancer Treatments

Various neurological complications, affecting both the central and peripheral nervous system, can frequently be experienced by cancer survivors after exposure to conventional chemotherapy, but also to modern immunotherapy. In this review, we provide an overview of the most well-known adverse events related to chemotherapy, with a focus on chemotherapy induced peripheral neurotoxicity, but we also address some emerging novel clinical entities related to cancer treatment, including chemotherapy-related cognitive impairment and immune-mediated adverse events. Unfortunately, efficacious curative or preventive treatment for all these neurological complications is still lacking. We provide a description of the possible mechanisms involved to drive future drug discovery in this field, both for symptomatic treatment and neuroprotection.

Blood-Based Biomarkers of Cancer-Related Cognitive Impairment in Non-Central Nervous System Cancer: A Scoping Review

This scoping review was designed to synthesize the extant literature on associations between subjective and/or objective measures of cancer-related cognitive impairment (CRCI) and blood-based biomarkers in adults with non-central nervous system cancers. The literature search was done for studies published from the start of each database searched (i.e., MEDLINE, Embase, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, Cochrane Central Register of Controlled Trials, grey literature) through to October 20, 2021. A total of 95 studies are included in this review. Of note, a wide variety of biomarkers were evaluated. Most studies evaluated patients with breast cancer. A variety of cognitive assessment measures were used. The most consistent significant findings were with various subjective and objective measures of CRCI and levels of interleukin-6 and tumor necrosis factor. Overall, biomarker research is in an exploratory phase. However, this review synthesizes findings and proposes directions for future research.

Classification of Chemotherapy-Related Subjective Cognitive Complaints in Breast Cancer Using Brain Functional Connectivity and Activity: A Machine Learning Analysis

The aim of this study was combining multi-level resting-state functional magnetic resonance imaging (rs-fMRI) features with machine learning method to distinguish breast cancer patients with chemotherapy-related subjective cognitive complaints (SCC) from non-chemotherapy (BC) and healthy controls (HC). Forty subjects in SCC group, forty-nine in BC group and thirty-four in HC group were recruited and underwent rs-fMRI scanning. Based on the anatomical automatic labeling brain atlas, the functional metrics of all subjects included functional connectivity, amplitude of low frequency fluctuation and fractional amplitude of low frequency fluctuation, regional homogeneity, voxel-mirrored homotopic connectivity and degree centrality were calculated and extracted as features set. Then, the rs-fMRI features were selected by two-sample t-test, removing variables with a high pairwise correlation and least absolute shrinkage and selection operator regression. Finally, the support vector machine models were built for classification (SCC vs. BC, SCC vs. HC). Thirty-eight features (SCC vs. BC) and seventeen features (SCC vs. HC) were selected separately, and the accuracy of the models were 82.0% and 91.9%, respectively. These findings demonstrated a valid machine learning approach that effectively distinguished breast cancer patients with chemotherapy-related SCC from non-chemotherapy and healthy controls, providing potential neuroimaging evidence for early diagnosis and clinical intervention of chemotherapy-related SCC.

Reliability and validity of a novel cognitive self-assessment tool for patients with cancer

Background

Subjective cognitive function is an important outcome measure in oncology. The Functional Assessment of Cancer Therapy-Brain (FACT-Br) is a quality of life (QoL) measure that includes indices of physical, emotional, social, and neurologic aspects of disease but does not measure cognitive function. This study seeks to validate a novel index of cognition derived from the FACT-Br.

Methods

Patients with heterogeneous cancer diagnoses (N = 214) completed neuropsychological evaluation and self-report measures. Nine FACT-Br items regarding cognition were combined to form the FACT-Br-cognitive index (CI). Reliability was evaluated by exploratory factor analysis and internal consistency. Concurrent validity was assessed by correlating FACT-Br-CI with the Patient-Reported Outcomes Measurement Information System (PROMIS) Cognitive-8 scales. Discriminant validity was assessed by correlating FACT-Br-CI with other FACT-Br indices and the Beck Depression and Anxiety Inventories (BDI, BAI). Exploratory analyses evaluated the impact of cognitive performance and disease variables on FACT-Br-CI.

Results

The FACT-Br-CI consisted of a single factor that demonstrated high internal consistency (α = 0.867) and strong concurrent validity, correlating strongly with PROMIS Cognitive-8 scales (r = 0.675-0.782). The relationship between the FACT-Br-CI and other FACT subscales ranged from moderate to strong (r = 0.372-0.601), as did correlations with measures of depression (BDI, r = -0.621) and anxiety (BAI, r = -0.450). Modest correlations were observed with neuropsychological measures (rs = 0.249-0.300).

Conclusions

The FACT-Br-CI is a reliable and valid measure of self-reported cognition. Studies that included the FACT-Br could be retrospectively analyzed to assess subjective cognitive outcomes, enriching the information from prior research. Integration of the FACT-Br-CI in routine clinical care may be an efficient method of monitoring cognition.

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.

Altered Functional Connectivity Density in Young Survivors of Acute Lymphoblastic Leukemia Using Resting-State fMRI

Objective

Using functional connectivity density (FCD) mapping measured by resting-state functional magnetic resonance imaging (rs-fMRI), an ultrafast data-driven graph theory approach, we attempted to study the abnormalities in neural activity of young survivors of acute lymphoblastic leukemia (ALL) and to explore the neuropathological evidence of chemotherapy-related cognitive impairment of patients.

Methods

Twenty young survivors of ALL and 18 well-matched healthy controls (HCs) were recruited in this study. All ALL patients and healthy controls underwent rs-fMRI scans and completed neurocognitive testing. The between-group differences in short-range and long-range FCD were calculated by the option of degree centrality (DC) in MATLAB software after preprocessing. The correlations between the FCD value and each of the neurocognitive outcomes were analyzed in the ALL patients.

Results

The group-averaged FCD maps showed similar spatial patterns between the two groups. Compared with the HCs, ALL patients showed decreased long-range FCD in regions of the bilateral lingual gyrus, cingulate cortex, hippocampal gyrus, and right calcarine fissure. Simultaneously, decreased regions in the short-range FCD map were the bilateral lingual gyrus, cingulate cortex, parahippocampal gyrus and right calcarine fissure. Increased functional connectivity (FC) was observed between the region with decreased long-range FCD and the posterior cerebellar lobe, and decreased FC was observed between the region and the middle occipital gyrus, cuneus and lingual gyrus. Thus, there existed no brain areas with increased FCD. The decreased short-range FCD value of ALL patients was positively correlated with the score on the Digit Span Test (Forward), and the increased FC value was negatively correlated with the score on the Trail Making Test part A.

Conclusion

Our results suggest the altered functional connectivity of young survivors of ALL in the posterior region of the brain and posterior lobe of the cerebellum. Alterations in spontaneous neuronal activity seem to parallel the neurocognitive testing, which indicates that the rs-fMRI could be used as a neuroimaging marker for neurological impairment in ALL patients.

Loss of Adaptive Myelination Contributes to Methotrexate Chemotherapy-Related Cognitive Impairment

Activity-dependent myelination is thought to contribute to adaptive neurological function. However, the mechanisms by which activity regulates myelination and the extent to which myelin plasticity contributes to non-motor cognitive functions remain incompletely understood. Using a mouse model of chemotherapy-related cognitive impairment (CRCI), we recently demonstrated that methotrexate (MTX) chemotherapy induces complex glial dysfunction for which microglial activation is central. Here, we demonstrate that remote MTX exposure blocks activity-regulated myelination. MTX decreases cortical Bdnf expression, which is restored by microglial depletion. Bdnf-TrkB signaling is a required component of activity-dependent myelination. Oligodendrocyte precursor cell (OPC)-specific TrkB deletion in chemotherapy-naive mice results in impaired cognitive behavioral performance. A small-molecule TrkB agonist rescues both myelination and cognitive impairment after MTX chemotherapy. This rescue after MTX depends on intact TrkB expression in OPCs. Taken together, these findings demonstrate a molecular mechanism required for adaptive myelination that is aberrant in CRCI due to microglial activation.

Methotrexate Chemotherapy Induces Persistent Tri-glial Dysregulation that Underlies Chemotherapy-Related Cognitive Impairment

Chemotherapy results in a frequent yet poorly understood syndrome of long-term neurological deficits. Neural precursor cell dysfunction and white matter dysfunction are thought to contribute to this debilitating syndrome. Here, we demonstrate persistent depletion of oligodendrocyte lineage cells in humans who received chemotherapy. Developing a mouse model of methotrexate chemotherapy-induced neurological dysfunction, we find a similar depletion of white matter OPCs, increased but incomplete OPC differentiation, and a persistent deficit in myelination. OPCs from chemotherapy-naive mice similarly exhibit increased differentiation when transplanted into the microenvironment of previously methotrexate-exposed brains, indicating an underlying microenvironmental perturbation. Methotrexate results in persistent activation of microglia and subsequent astrocyte activation that is dependent on inflammatory microglia. Microglial depletion normalizes oligodendroglial lineage dynamics, myelin microstructure, and cognitive behavior after methotrexate chemotherapy. These findings indicate that methotrexate chemotherapy exposure is associated with persistent tri-glial dysregulation and identify inflammatory microglia as a therapeutic target to abrogate chemotherapy-related cognitive impairment. VIDEO ABSTRACT.

Self-reported chemotherapy-related cognitive impairment compared with cognitive complaints following menopause

OBJECTIVE

Cancer-related cognitive impairment (CRCI) is commonly reported following the administration of cancer treatment. Current longitudinal studies, primarily in women with breast cancer, suggest that up to 35% to 60% of patients exhibit persistent CRCI (pCRCI) following completion of chemotherapy. Complaints of subjective cognitive decline (SCD) are also commonly reported by women during and following the menopause transition in noncancer patients. Although the majority of evidence for cognitive difficulties in cancer patients and survivors is attributed to chemotherapy, there is growing evidence to suggest that menopausal status can also influence cognitive function in cancer patients.

METHODS

Given that menopausal status may be contributing to pCRCI, we compared a group of primarily postmenopausal women with pCRCI to 2 groups of postmenopausal women: women who endorse menopause-associated SCD (maSCD+) and women who do not (maSCD-) to explore the similarities/differences between maSCD and pCRCI and the potential role of menopause in pCRCI.

RESULTS

Persistent CRCI participants report more severe SCD symptoms than women after natural menopause, despite being on average 2.5-year postchemotherapy, supporting previous findings that CRCI can persist for months to years after completing treatment. Persistent CRCI participants not only endorsed greater SCD but also exhibited objective performance differences. In addition, pCRCI participants endorsed significantly greater menopausal symptoms compared with either maSCD group. Results were not related to menopausal status prior to chemotherapy or current endocrine therapy use.

CONCLUSIONS

These results suggest that while menopausal symptoms may contribute to SCD experienced by cancer patients after chemotherapy, they do not fully account for pCRCI.

What is known and unknown about chemotherapy-related cognitive impairment in patients with haematological malignancies and areas of needed research

Cancer-related cognitive impairment (CRCI) is an important clinical problem for cancer patients and survivors. In this review, we summarize studies investigating the occurrence of impaired cognition in patients with haematological malignancies. Most published studies focus on survivors of childhood acute lymphoblastic leukaemia and primary central nervous system lymphoma. We also discuss studies conducted in acute myeloid leukaemia, myelodysplastic syndromes, chronic myeloid leukaemia, Hodgkin lymphoma (HL), non-HL and chronic lymphocytic leukaemia. Although research in this area is still emerging, it appears that a subset of chemotherapy-treated haematological malignancy survivors experience CRCI. Future research should focus on expanding the literature reviewed here with larger studies appropriately powered to assess cognition via objective and subjective measures in a longitudinal fashion to tease apart the impact of disease and the various forms of cancer treatment.