Neurotoxic complications of chemotherapy in patients with cancer: clinical signs and optimal management

Improving health engagement and lifestyle management for breast cancer survivors with diabetes

Breast cancer survivors with type 2 diabetes are at high risk for cancer recurrence, serious health complications, more severe symptoms, psychological distress, and premature death relative to breast cancer survivors without diabetes. Maintaining glycemic control is critical for decreasing symptoms and preventing serious health problems. Many breast cancer survivors with type 2 diabetes have difficulty maintaining diabetes self-management behaviors and achieving glycemic control. Both cancer and diabetes-related symptoms (e.g., physical symptoms and psychological distress) are often barriers to engaging in diabetes self-management strategies. This study evaluates a novel diabetes coping skills training (DCST) intervention for improving breast cancer survivors' abilities to manage symptoms and adhere to recommended diabetes self-management behaviors. The telephone-based DCST protocol integrates three key theory-based strategies: coping skills training for managing symptoms, adherence skills training, and healthy lifestyle skills training. A randomized clinical trial will test the DCST intervention plus diabetes education by comparing it to diabetes education alone. Symptoms, distress, diabetes self-management behaviors, and self-efficacy will be assessed at baseline and 3, 6, and 12 months. Glycosylated hemoglobin (HbA1c) will be assessed at baseline, 6, and 12 months. This study addresses a critical gap in the care of breast cancer survivors by evaluating a novel behavioral intervention to improve the management of symptoms, adherence, and glycemic control in breast cancer survivors with type 2 diabetes. Special considerations for this medically underserved population are also provided. The findings of this study could lead to significant improvements in clinical care and beneficial outcomes for breast cancer survivors. Trials registration: ClinicalTrials.gov, NCT02970344, registered 11/22/2016.

Nose-to-Brain Delivery of Cancer-Targeting Paclitaxel-Loaded Nanoparticles Potentiates Antitumor Effects in Malignant Glioblastoma

Glioblastoma multiforme (GBM) is an aggressive tumor with no curative treatment. The tumor recurrence after resection often requires chemotherapy or radiation to delay the infiltration of tumor remnants. Intracerebral chemotherapies are preferentially being used to prevent tumor regrowth, but treatments remain unsuccessful because of the poor drug distribution in the brain. In this study, we investigated the therapeutic efficacy of cancer-targeting arginyl-glycyl-aspartic tripeptide (RGD) conjugated paclitaxel (PTX)-loaded nanoparticles (NPs) against GBM by nose-to-brain delivery. Our results demonstrated that RGD-modified PTX-loaded NPs showed cancer-specific delivery and enhanced anticancer effects in vivo. The intranasal (IN) inoculation of RGD-PTX-loaded NPs effectively controls the tumor burden (75 ± 12% reduction) by inducing apoptosis and/or inhibiting cancer cell proliferation without affecting the G₀ stage of normal brain cells. Our data provide therapeutic evidence supporting the use of intranasally delivered cancer-targeted PTX-loaded NPs for GBM therapy.

Diabetes and Clinical Outcome in Patients With Metastatic Colorectal Cancer: CALGB 80405 (Alliance)

BACKGROUND

Diabetes is a prognostic factor for some malignancies, but its association with outcome in patients with advanced or metastatic colorectal cancer (CRC) is less clear.

METHODS

This cohort study was nested within a randomized trial of first-line chemotherapy and bevacizumab and/or cetuximab for advanced or metastatic CRC. Patients were enrolled at 508 community and academic centers throughout the National Clinical Trials Network. The primary exposure was physician-documented diabetes at the time of enrollment. The primary endpoint was overall survival (OS); secondary endpoints were progression-free survival (PFS) and adverse events. Tests of statistical significance were two-sided.

RESULTS

Among 2326 patients, 378 (16.3%) had diabetes. The median follow-up time was 6.0 years. We observed 1973 OS events and 2173 PFS events. The median time to an OS event was 22.7 months among those with diabetes and 27.1 months among those without diabetes (HR = 1.27, 95% CI = 1.13 to 1.44; P < .001). The median time to a PFS event was 9.7 months among those with diabetes and 10.8 months among those without diabetes (HR = 1.16, 95% CI = 1.03 to 1.30; P = .02). Patients with diabetes were more likely to experience no less than grade 3 hypertension (8.1% vs 4.4%; P = .054) but were not more likely to experience other adverse events, including neuropathy.

CONCLUSIONS

Diabetes is associated with an increased risk of mortality and tumor progression in patients with advanced or metastatic CRC. Patients with diabetes tolerate first-line treatment with chemotherapy and monoclonal antibodies similarly to patients without diabetes.

The impact of neuroimaging advancement on neurocognitive evaluation in pediatric brain tumor survivors: A review

Pediatric brain tumors are a type of tumors that are commonly present in children and young adults. With the improvement of treatment, the quality of life, especially the cognitive functioning, is gaining increasingly more attention. Apart from cognitive evaluations, neuroimaging studies begin to play an important part in neurocognitive functioning investigation. In this way, the brain tissue changes caused by tumor variables (including tumor location and tumor size) and treatment variables (including surgery, chemotherapy and radiotherapy) can be detected by neuroimaging. Recent advancement of neuroimaging techniques, such as functional-MRI (fMRI) and diffusion tensor imaging (DTI), made great contributions to understanding cognitive dysfunction and quantifying the effects of tumor variables and treatment variables. In recent years, laminar-fMRI provided a potentially valuable tool for examining the exact origins of neural activity and cognitive function. On the other hand, molecular fMRI might guide diagnosis and treatment of brain disease in the future by using new biomarkers, and DTI can detect white matter changes and obtain some anatomically specific information.

A Randomized, Placebo-Controlled Trial Evaluating Changes in Peripheral Neuropathy and Quality of Life by Using Low-Frequency Electrostimulation on Breast Cancer Patients Treated With Chemotherapy

Background: This study examined the effect of a portable low-frequency electrostimulation (ES) device on patients diagnosed with chemotherapy-induced peripheral neuropathy (CIPN) immediately after chemotherapy for breast cancer. Methods: A single-center, randomized, placebo-controlled trial was conducted. A total of 72 patients newly diagnosed with CIPN were enrolled and randomly placed into the ES (n = 36) or the sham ES group (SES; n = 36). Duloxetine or pregabalin was prescribed to all participants from the initial assessment. The devices for 14 days, at least twice a day, for at least 120 minutes. The primary outcomes were the overall intensities of the CIPN symptoms as assessed using Numerical Rating Scale (NRS). Secondary outcomes included Total Neuropathy Score (TNS), European Organization for Research and Treatment of Cancer Quality of Life (EORTC-QLQ), Chemotherapy-Induced Peripheral Neuropathy 20 (CIPN20), Functional Assessment of Cancer Therapy-Breast (FACT-B), and Instrument on Pattern Identification and Evaluation for CIPN (IPIE-CIPN). Results: No differences in NRS scores were found between the patients in the ES and the SES group (P = 0.267). Patients in both groups showed significantly reduced CIPN intensities (ES P < .001; SES P < .001). No significant differences between the groups were found in TNS, EORTC-QLQ, CIPN20, and FACT-B. The general symptoms of CIPN diagnosed as cold arthralgia showed significance only in the ES group (P = .006). Conclusion: Compared with a placebo, the effectiveness of the low-frequency ES device with pharmacological intervention was not significantly different, but a therapeutic effect was possible.

Overview of cisplatin-induced neurotoxicity and ototoxicity, and the protective agents

Cisplatin has dramatically improved the survival rate of cancer patients, but it has also increased the prevalence of hearing and neurological deficits in this population. Cisplatin induces ototoxicity, peripheral (most prevalent) and central (rare) neurotoxicity. This review addresses the ototoxicity and the neurotoxicity associated with cisplatin-based chemotherapy, providing an integrated view of the potential protective agents that have been evaluated in vitro, in vivo and in clinical trials, their targets and mechanisms of protection and their effects on the antitumor activity of cisplatin. So far, the findings are insufficient to support the use of any oto- or neuroprotective agent before, during or after cisplatin chemotherapy. Despite their promising effects in vitro and in animal studies, many agents have not been evaluated in clinical trials. Additionally, the clinical trials have limitations concerning the sample size, controls, measurement, heterogeneous groups, several arms of treatment, short follow-up or no blinding. Besides that, for most agents, the effects on the antitumor activity of cisplatin have not been evaluated in tumor-bearing animals, which discourages clinical trials. Further well-designed randomized controlled clinical trials are necessary to definitely demonstrate the effectiveness of the oto- or neuroprotective agents proposed by animal and in vitro studies.

Systematic Evaluation of Neurotoxicity in Children and Young Adults Undergoing CD22 Chimeric Antigen Receptor T-Cell Therapy

Neurotoxicity associated with CAR-T cell therapy can be life-threatening. With rapid development of CAR-T therapies, a systematic method is needed to identify and monitor symptoms of neurotoxicity, elucidate potential etiologies, and compare toxicity across trials. This paper presents a systematic evaluation developed and used to prospectively assess neurotoxicity in our phase I anti-CD22 CAR-T-cell trial and describes the symptoms of neurotoxicity identified using this methodology. Central nervous system (CNS) studies included routine lumbar punctures performed for disease evaluation pretherapy and posttherapy and a baseline brain MRI. Brief cognitive evaluations, assessing 4 domains (attention, working memory, cognitive flexibility, and processing speed), were administered preinfusion and postinfusion. A newly developed CAR-T-specific neurological symptom checklist (NSC) was completed by caregivers at 3 designated time-points. Serial serum cytokine levels were compared with neurotoxicity symptoms and severity. The majority of the first 22 consecutively treated subjects (ages, 7-30) demonstrated stable or improved cognitive test scores following therapy and no irreversible neurotoxicity, despite CAR-T-related antileukemic response, cytokine release syndrome, and trafficking of CAR-T cells to the CSF. The NSC allowed us to document the type and timing of symptoms and explore the etiology of neurotoxicity associated with CD22 CAR-T therapy. Cytokine profiling demonstrated that more concerning symptoms of neurotoxicity, such as hallucination and disorientation, were significantly associated with higher serum cytokine levels, supporting the hypothesis of inflammation-driven neurotoxicity. Systematic assessments of neurotoxicity were feasible in acutely ill children and young adults and served to characterize and monitor the symptoms associated with CAR-T therapy. We recommend these evaluations be incorporated into future immunotherapy protocols.

Chemotherapy-Related Encephalopathy With Super-Refractory Status Epilepticus in a Child With Osteosarcoma: A Case Report With a Review of Literature

Osteosarcoma is the most frequent primary cancer of the bones, and a combination of primary chemotherapy, surgery, and adjuvant chemotherapy is its current treatment. In adults, some authors have reported problems with memory and concentration following chemotherapy, but in children, severe neurologic dysfunction has been rarely reported. This report describes a 13-year-old patient with primary high-grade nonmetastatic osteosarcoma of the tibia who developed encephalopathy with super-refractory status epilepticus related to chemotherapy. He received methotrexate (MTX) and cisplatin (CDDP)-containing polychemotherapy, and after the first course of drug administration, he developed fever, confusion, a state of psychomotor agitation, and super-refractory status epilepticus with normal laboratory and imaging findings. The causal relationship between the administration of the first polychemotherapy course and his neurological manifestations may be supported by the evaluation and exclusion of other causes. The administration of antiepileptic drugs and off-label atypical antipsychotics was necessary to treat his neurological complications and behavioral changes. This patient represents the first known example of super-refractory status epilepticus in a child treated with MTX and CDDP-containing chemotherapy. Physicians should be aware that encephalopathy and seizures are possible consequences of CDDP therapy when administered alone or in combination with other chemotherapeutic agents. Further studies are needed to better define this relationship in children.

Antioxidant Effects of Satureja hortensis L. Attenuate the Anxiogenic Effect of Cisplatin in Rats

Numerous adverse effects of cisplatin-based therapy are usually accompanied by enhanced oxidative damage and cell apoptosis in various tissues. Even neurotoxic manifestations of cisplatin administration, such as the anxiogenic effect, appear along with the increased oxidative stress and apoptotic indicators in certain brain regions. Thirty-five Wistar albino male rats were divided into seven groups: control, cisplatin (received a single dose of cisplatin: 7.5 mg/kg), three groups with oral administration of Satureja hortensis L. methanolic extract (SH) (low: 50 mg/kg, middle: 100 mg/kg, and high dose: 200 mg/kg) along with cisplatin application, a group with the extract in high dose alone, and a silymarin group (cisplatin and silymarin: 100 mg/kg), in order to evaluate the antioxidant effects of SH on cisplatin-induced increase in the anxiety level. After completing 10-day pretreatments, behavioral testing was performed in the open field and the elevated plus maze, followed by an investigation of oxidative stress and apoptosis parameters in hippocampal tissue samples. Cisplatin administration resulted in anxiogenic-like behavior, increased lipid peroxidation, and proapoptotic markers accompanied by the decline in antioxidant and antiapoptotic defense. The administration of extract alone did not significantly alter any of the estimated parameters. When applied along with cisplatin, SH in a dose of 100 mg/kg induced the significant anxiolytic effect with concomitant recovery of antioxidant and antiapoptotic activity indicators, while both lower and higher doses of the extract failed to improve the adverse effects of cisplatin administration. The beneficial effects of the middle dose of SH were equivalent to the same dose of silymarin, as a “golden standard.” Our results indicate that the antioxidant supplementation with SH in an optimal dose significantly improved the oxidative status and it had antiapoptotic effect in the rat hippocampus disturbed by cisplatin administration, which was accompanied with attenuation of cisplatin-induced anxiogenic effect.

Neuropsychological disorders in non-central nervous system cancer: a review of objective cognitive impairment, depression, and related rehabilitation options

AIM

The objective of the present review was to systematically characterize the types of cognitive impairment that are found in different non-brain types of cancer as measured by objective and validated tests, and also to further examine depression and cognitive function in cancer patients and explore their available rehabilitation treatments.

RESULTS

A total of 29 articles were reviewed. Most of these studies suggest that chemotherapy as well as the combination of chemotherapy and hormonal therapy can influence cognition in different types of cancer patients. Breast cancer patients appear to be the most affected in neuropsychological function, specifically in terms of cognitive impairment and reduced quality of life, as compared to other non-brain solid tumours. Overall, the most impaired functions were verbal ability, memory, executive function, and motor speed.

CONCLUSION

Chemotherapy-related cognitive dysfunction remains under-recognized and undertreated. The various studies reported differing and non-homogenous findings with mixed results, obtained by self-reporting and web-assisted assessment, with other confounding factors such as age and depression during both cancer diagnosis and treatment. An objective neuropsychological assessment is fundamental to avoid underestimation of the extent of chemobrain. Self-reported and web-assisted assessment may ultimately result in confusion between the neuropsychological signs of chemobrain versus those of depression.

Novel trastuzumab-DM1 conjugate: Synthesis and bio-evaluation

Antibody-drug conjugates are now of considerable interest and are recommended for the treatment of cancers. Linkers are having a crucial role in potency and efficacy of these drugs. Herein, for the first time, we have used a water-soluble poly-ethylene glycol based linker (succinimidyl-[(N-maleimido propionamido)-diethyleneglycol] [SM(PEG)2]) for lysine amide coupling of DM1 drug to trastuzumab considering evaluation of the effect of using a hydrophilic linker on physicochemical and biological properties of the resulting conjugate in comparison to the conjugate containing succinimidyl 4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) linker, which has a relative hydrophobic nature. The physicochemical properties of synthesized conjugates were investigated in terms of drug to antibody ratio, size variants and free drug quantities. In vitro biological activity of trastuzumab-DM1 conjugates was assessed on breast cancer cell lines expressing different levels of HER2 using binding affinity, antiproliferative, apoptosis, and antibody-dependent cell-mediated cytotoxicity (ADCC) assays. Synthesized conjugate containing hydrophilic linker, showed higher drug to antibody ratio, no aggregated form and higher cellular toxicity in comparison to SMCC bearing conjugate. Binding affinity and ADCC potential of conjugates was not affected upon the usage of hydrophilic linker. In conclusion, application of SM(PEG)2 for coupling of DM1 to trastuzumab enhance desirable characteristics of the resulting conjugate.

Preventive action of benztropine on platinum-induced peripheral neuropathies and tumor growth

The endogenous cholinergic system plays a key role in neuronal cells, by suppressing neurite outgrowth and myelination and, in some cancer cells, favoring tumor growth. Platinum compounds are widely used as part of first line conventional cancer chemotherapy; their efficacy is however limited by peripheral neuropathy as a major side-effect. In a multiple sclerosis mouse model, benztropine, that also acts as an anti-histamine and a dopamine re-uptake inhibitor, induced the differentiation of oligodendrocytes through M1 and M3 muscarinic receptors and enhanced re-myelination. We have evaluated whether benztropine can increase anti-tumoral efficacy of oxaliplatin, while preventing its neurotoxicity.We showed that benztropine improves acute and chronic clinical symptoms of oxaliplatin-induced peripheral neuropathies in mice. Sensory alterations detected by electrophysiology in oxaliplatin-treated mice were consistent with a decreased nerve conduction velocity and membrane hyperexcitability due to alterations in the density and/or functioning of both sodium and potassium channels, confirmed by action potential analysis from ex-vivo cultures of mouse dorsal root ganglion sensory neurons using whole-cell patch-clamp. These alterations were all prevented by benztropine. In oxaliplatin-treated mice, MBP expression, confocal and electronic microscopy of the sciatic nerves revealed a demyelination and confirmed the alteration of the myelinated axons morphology when compared to animals injected with oxaliplatin plus benztropine. Benztropine also prevented the decrease in neuronal density in the paws of mice injected with oxaliplatin. The neuroprotection conferred by benztropine against chemotherapeutic drugs was associated with a lower expression of inflammatory cytokines and extended to diabetic-induced peripheral neuropathy in mice.Mice receiving benztropine alone presented a lower tumor growth when compared to untreated animals and synergized the anti-tumoral effect of oxaliplatin, a phenomenon explained at least in part by benztropine-induced ROS imbalance in tumor cells.This report shows that blocking muscarinic receptors with benztropine prevents peripheral neuropathies and increases the therapeutic index of oxaliplatin. These results can be rapidly transposable to patients as benztropine is currently indicated in Parkinson's disease in the United States.

Retinal and Preretinal Hemorrhages in a Patient Receiving Hyper-CVAD Chemotherapy for T-Cell Acute Lymphoblastic Leukemia

Hyperfractionated cyclophosphamide, vincristine, adriamycin, and dexamethasone (Hyper-CVAD) is an important chemotherapeutic regimen for acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma. We present a case of a 23-year-old male with T-cell ALL and visual acuity of 20/20 in the right eye and 20/25 in the left eye who developed significant changes in his vision after starting Hyper-CVAD therapy. The patient initially presented with cotton wool spots in the fundus shortly after starting the regimen. After going through the induction phase of chemotherapy, he had a sudden decline in his vision to light perception in the left eye. Posterior segment exam revealed retinal ischemia and multilayered hemorrhages in both eyes as well as a large preretinal hemorrhage obscuring the fovea in the left eye. Labs associated the appearance of these hemorrhages with a significant decrease in hemoglobin and a platelet count of 5 K/μL. A Nd:YAG laser applied in the left eye at the posterior hyaloid face allowed blood to drain into the vitreous cavity and brought the patient's visual acuity back to baseline. Hyper-CVAD is an aggressive chemotherapy regimen that can cause severe thrombocytopenia secondary to myelosuppression. Frequent retinal evaluations and timely intervention is advisable in these cases as extensive intraretinal hemorrhages may cause irreversible damage.

Chemotherapy and Inflammatory Cytokine Signalling in Cancer Cells and the Tumour Microenvironment

Cancer is the result of a cell's acquisition of a variety of biological capabilities or 'hallmarks' as outlined by Hanahan and Weinberg. These include sustained proliferative signalling, the ability to evade growth suppressors, resisting cell death, enabling replicative immortality, inducing angiogenesis, and the ability to invade other tissue and metastasize. More recently, the ability to escape immune destruction has been recognized as another important hallmark of tumours. It is suggested that genome instability and inflammation accelerates the acquisition of a variety of the above hallmarks. Inflammation, is a product of the body's response to tissue damage or pathogen invasion. It is required for tissue repair and host defense, but prolonged inflammation can often be the cause for disease. In a cancer patient, it is often unclear whether inflammation plays a protective or deleterious role in disease progression. Chemotherapy drugs can suppress tumour growth but also induce pathways in tumour cells that have been shown experimentally to support tumour progression or, in other cases, encourage an anti-tumour immune response. Thus, with the goal of better understanding the context under which each of these possible outcomes occurs, recent progress exploring chemotherapy-induced inflammatory cytokine production and the effects of cytokines on drug efficacy in the tumour microenvironment will be reviewed. The implications of chemotherapy on host and tumour cytokine pathways and their effect on the treatment of cancer patients will also be discussed.

Prediction of Chemotherapy-Induced Peripheral Neuropathy in Patients with Lymphoma and Myeloma: the Roles of Brain-Derived Neurotropic Factor Protein Levels and A Gene Polymorphism

Background and Purpose

Brain-derived neurotrophic factor (BDNF) is a neuronal growth factor that plays an essential role in the maintenance of the nervous system. We have evaluated the peripheral blood protein levels of BDNF and the valine-to-methionine substitution at codon 66 (Val66Met) single-nucleotide polymorphism (SNP) as potential biomarkers for the early recognition of chemotherapy-induced peripheral neuropathy (CIPN) in non-Hodgkin lymphoma and multiple myeloma patients.

Methods

CIPN was assessed in 45 patients at the diagnosis and during vincristine or bortezomib-based therapy using objective [reduced version of the Total Neuropathy Score (TNSr)] and subjective (FACT-GOG-NTx) tools. Depression was assessed using the Patient Health Questionnaire-9 (PHQ-9) questionnaire. BDNF protein levels and the Val66Met SNP were determined using ELISA and Sanger sequencing.

Results

The pretreatment BDNF protein level was inversely correlated with the maximum TNSr, FACT-GOG-NTx, and PHQ-9 scores in both genotypes. BDNF patients with the Val/Val genotype demonstrated significantly higher maximum FACT-GOG-NTx and PHQ-9 scores than those with the Val/Met and Met/Met genotypes (Met-BNDF carriers). Correlations between PHQ-9 and TNSr score were found only in Met-BDNF carriers, suggesting that peripheral neuropathy and depression coincide in Met-BDNF carriers.

Conclusions

Determining the BDNF protein levels before initiating chemotherapy might be a useful tool for CIPN risk assessment and preemptive dose modification. The present data should be validated in larger studies that include other neurotoxic agents.

[White matter alterations after chemotherapy and radiation]

Nowadays chemotherapy and radiotherapy are fundamental therapy concepts in the guidelines of malignant tumors of the central nervous system. Both therapy concepts can cause neurological symptoms or white matter alterations can occur, which can be classified into acute, subacute and chronic. Both symptoms and white matter alterations during acute and subacute phases are in most cases completely reversible, whereas chronic white matter alterations can lead to severe neurological limitations and further impair the quality of life of cancer patients.

The evaluation of changes in peripheral neuropathy and quality-of-life using low-frequency electrostimulation in patients treated with chemotherapy for breast cancer: a study protocol

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a progressive, enduring, and sometimes irreversible neurotoxic symptom that occurs in 30-40% of chemotherapy-treated cancer patients. CIPN negatively affects both the patient's abilities to perform daily activities and their health-related quality of life (HRQOL) after chemotherapy treatment. Although this neuropathy has been treated with duloxetine and/or gabapentin, limited therapeutic benefits have been reported, thereby necessitating the development of an integrated approach that combines pharmacological management and complementary methods such as acupuncture and electric nerve stimulation. Therefore, this study is designed to examine the effect of a portable, low-frequency electrostimulation (ES) device on CIPN symptoms and HRQOL of female patients diagnosed with CIPN immediately after chemotherapy for breast cancer.

METHODS

This study is a single-center, randomized, placebo-controlled trial with two parallel groups and a 2-week follow-up. We will enroll 80 breast cancer patients who are newly diagnosed with CIPN after chemotherapy. Duloxetine or pregabalin will be prescribed to all participants from the initial assessment. Half of the patients will be assigned into the experimental group and the other half to the control group. The CarebandR (Piomed Inc., Seoul, Korea), a wearable wristband that generates low-frequency electrostimulation, will be administered only to the experimental group. Electrostimulation will be administered on the unilateral PC6 acupoint. A numerical rating scale will be used to assess the overall intensity of CIPN symptoms. The key secondary outcome variables include patient-reported CIPN symptom distress tested by a self-rated questionnaire, physician-rated symptom severity assessed by the Total Neuropathy Score, and HRQOL.

DISCUSSION

It is expected that the combination of a low-frequency electrostimulation device and pharmacological intervention (duloxetine or pregabalin) will produce synergistic effects in breast cancer patients with CIPN after treatment. To our knowledge, this is the first study to investigate the beneficial effect of a new integrated approach for CIPN management after breast cancer treatment. The study findings can expand our knowledge and understanding of the occurrence of CIPN and the efficacy of integrated intervention efforts to ameliorate CIPN symptoms.

TRIAL REGISTRATION

Clinical Research Information Service (CRIS), Republic of Korea, ID: KCT0002357 . Registered retrospectively on 13 June 2017.

Living with chemotherapy-induced peripheral neuropathy: Uncovering the symptom experience and self-management of neuropathic symptoms among cancer survivors

PURPOSE

The study aimed at uncovering the symptom experience of neurotoxicity, self-adopted approaches and perspectives in managing chemotherapy-induced peripheral neuropathic (CIPN) symptoms in a sample of Chinese cancer survivors.

METHODS

A qualitative descriptive study was used to explore individual experiences. A purposive sample of 12 female participants experiencing CIPN was invited to semi-structured interviews who were part of a larger prospective observational study investigating the natural progression and risk factors of CIPN. Textual interview data were managed in NVivo. Content analysis was used.

RESULTS

Participants were aged 41-64 years and experienced moderate to severe neuropathic symptoms from 5 to 23 months after completion of a six-cycle chemotherapy regimens at reported during the interviews. Four categories emerged from the qualitative data, namely, (1) experience come to reality: characteristics of CIPN symptoms, (2) disruptions and perceived threat: ability to perform activities and resume work, (3) re-establishing an 'at least satisfactory level of well-being', and (4) views of and approaches in managing neuropathic symptoms.

CONCLUSIONS

The characteristics of CIPN symptoms causing disruptions in functional and/or psychosocial well-being from the patients' perspectives and the self-help strategies used to manage symptoms showed a need to provide quality multidisciplinary supportive care, focusing on restoring functional and psychosocial well-being, and enhancing knowledge about symptom assessment and evidence-based strategies for empowering cancer survivors to cope with this complex symptom.

Neurocognitive and Psychosocial Outcomes in Pediatric Brain Tumor Survivors

The late neurocognitive and psychosocial effects of treatment for pediatric brain tumor (PBT) represent important areas of clinical focus and ongoing research. Neurocognitive sequelae and associated problems with learning and socioemotional development negatively impact PBT survivors' overall health-related quality of life, educational attainment and employment rates. Multiple factors including tumor features and associated complications, treatment methods, individual protective and vulnerability factors and accessibility of environmental supports contribute to the neurocognitive and psychosocial outcomes in PBT survivors. Declines in overall measured intelligence are common and may persist years after treatment. Core deficits in attention, processing speed and working memory are postulated to underlie problems with overall intellectual development, academic achievement and career attainment. Additionally, psychological problems after PBT can include depression, anxiety and psychosocial adjustment issues. Several intervention paradigms are briefly described, though to date research on innovative, specific and effective interventions for neurocognitive late effects is still in its early stages. This article reviews the existing research for understanding PBT late effects and highlights the need for innovative research to enhance neurocognitive and psychosocial outcomes in PBT survivors.

Balance and Gait Impairment: Sensor-Based Assessment for Patients With Peripheral Neuropathy

BACKGROUND

Individuals with peripheral neuropathy (PN) frequently experience balance and gait impairments that can lead to poor physical function, falls, and injury. Nurses are aware that patients with cancer experience balance and gait impairments but are unsure of optimal assessment and management strategies.

OBJECTIVES

This article reviews options for balance and gait assessment for patients diagnosed with cancer experiencing PN, describes advantages and limitations of the various options, and highlights innovative, clinically feasible technologies to improve clinical assessment and management.

METHODS

The literature was reviewed to identify and assess the gold standard quantitative measures for assessing balance and gait.

FINDINGS

Gold standard quantitative measures are burdensome for patients and not often used in clinical practice. Sensor-based technologies improve balance and gait assessment options by calculating precise impairment measures during performance of simple clinical tests at the point of care.

Mediating Effect of Postsurgical Chemotherapy on Presence of Dementia and Survival among Patients 65 and Older with Stage III Colon Cancer

Introduction: Both colon cancer and dementia are prevalent among the elderly and have a high risk of cooccurrence. Previous studies found that patients with dementia were treated less aggressively. In this study, we hypothesized that presence of preexisting dementia was associated with worse survival for stage III colon cancer patients, and that postoperative chemotherapy was on the causal pathway.Methods: We defined preexisting dementia in Surveillance Epidemiology and End Results Medicare data through either a formal diagnosis or a prescription for dementia drugs or both before the diagnosis of cancer. We applied multivariable Cox regression to estimate the effect of preexisting dementia on survival, adjusting for demographic factors, tumor characteristics, and receipt of chemotherapy. We assessed mediating effects in the context of the counterfactual framework using the accelerated failure time model.Results: There were 4,573 patients diagnosed with stage III colon cancer between 2007 and 2009 identified. A preexisting diagnosis of dementia significantly increased the risk of death by 45% (HR = 1.45, 95% CI: 1.29-1.63). Patients with either a formal diagnosis of dementia or a related prescription had significantly lower cause-specific survival than their cognitively healthy counterparts. Receipt of chemotherapy was a significant mediator on the causal pathway. The effect of presence of dementia was mediated by receipt of chemotherapy by 13% for preexisting dementia.Conclusions: Preexisting dementia is significantly associated with worse survival for stage III colon cancer patients, and its deleterious effect is partially explained by decreased likelihood of postoperative chemotherapy receipt.Impact: This is the first study that provides estimate of the mediating effect of diminished chemotherapy in patients with stage III colon cancer and dementia, simultaneously demonstrating the cancer-specific survival benefit of chemotherapy in the presence of dementia. Cancer Epidemiol Biomarkers Prev; 26(10); 1558-63. ©2017 AACR.

Insights into optic pathway glioma vision loss from mouse models of neurofibromatosis type 1

Neurofibromatosis type 1 (NF1) is a common cancer predisposition syndrome caused by mutations in the NF1 gene. The NF1-encoded protein (neurofibromin) is an inhibitor of the oncoprotein RAS and controls cell growth and survival. Individuals with NF1 are prone to developing low-grade tumors of the optic nerves, chiasm, tracts, and radiations, termed optic pathway gliomas (OPGs), which can cause vision loss. A paucity of surgical tumor specimens and of patient-derived xenografts for investigative studies has limited our understanding of human NF1-associated OPG (NF1-OPG). However, mice genetically engineered to harbor Nf1 gene mutations develop optic gliomas that share many features of their human counterparts. These genetically engineered mouse (GEM) strains have provided important insights into the cellular and molecular determinants that underlie mouse Nf1 optic glioma development, maintenance, and associated vision loss, with relevance by extension to human NF1-OPG disease. Herein, we review our current understanding of NF1-OPG pathobiology and describe the mechanisms responsible for tumor initiation, growth, and associated vision loss in Nf1 GEM models. We also discuss how Nf1 GEM and other preclinical models can be deployed to identify and evaluate molecularly targeted therapies for OPG, particularly as they pertain to future strategies aimed at preventing or improving tumor-associated vision loss in children with NF1.

Oxaliplatin-induced enteric neuronal loss and intestinal dysfunction is prevented by co-treatment with BGP-15

BACKGROUND AND PURPOSE

Gastrointestinal side effects of chemotherapy are an under-recognized clinical problem, leading to dose reduction, delays and cessation of treatment, presenting a constant challenge for efficient and tolerated anti-cancer treatment. We have found that oxaliplatin treatment results in intestinal dysfunction, oxidative stress and loss of enteric neurons. BGP-15 is a novel cytoprotective compound with potential HSP72 co-inducing and PARP inhibiting properties. In this study, we investigated the potential of BGP-15 to alleviate oxaliplatin-induced enteric neuropathy and intestinal dysfunction.

EXPERIMENTAL APPROACH

Balb/c mice received oxaliplatin (3 mg·kg^-1 ·day^-1 ) with and without BGP-15 (15 mg·kg^-1 ·day^-1 : i.p.) tri-weekly for 14 days. Gastrointestinal transit was analysed via in vivo X-ray imaging, before and after treatment. Colons were collected to assess ex vivo motility, neuronal mitochondrial superoxide and cytochrome c levels and for immunohistochemical analysis of myenteric neurons.

KEY RESULTS

Oxaliplatin-induced neuronal loss increased the proportion of neuronal NO synthase-immunoreactive neurons and increased levels of mitochondrial superoxide and cytochrome c in the myenteric plexus. These changes were correlated with an increase in PARP-2 immunoreactivity in the colonic mucosa and were attenuated by BGP-15 co-treatment. Significant delays in gastrointestinal transit, intestinal emptying and pellet formation, impaired colonic motor activity, reduced faecal water content and lack of weight gain associated with oxaliplatin treatment were restored to sham levels in mice co-treated with BGP-15.

CONCLUSION AND IMPLICATIONS

Our results showed that BGP-15 ameliorated oxidative stress, increased enteric neuronal survival and alleviated oxaliplatin-induced intestinal dysfunction, suggesting that BGP-15 may relieve the gastrointestinal side effects of chemotherapy.

Chemical analyses and in vitro and in vivo toxicity of fruit methanol extract of Sechium edule var. nigrum spinosum

CONTEXT

Sechium edule (Jacq.) Sw. (Cucurbitaceae) is used in ethnomedicine, but the diversity of the varietal groups of this species has not often been considered. This is important because we previously reported that different variety of species exhibit different activities across different tumor cell lines.

OBJECTIVE

This study investigates the chemical composition and biological activities of extracts obtained from S. edule var. nigrum spinosum.

MATERIALS AND METHODS

The leukemia P388 cell line and mononuclear bone marrow cells (MNCBMs) were treated with the extract at a concentration ranging from 40 to 2370 μg/mL for cytotoxicity and viability assays. CD-1 mice were treated with 8-5000 mg/kg extract and monitored every hour for the first 24 h and subsequently for seven days for signs of toxicity (LD₅₀). In addition, the chromatographic profile of the extract was determined by HPLC.

RESULTS

The extract inhibits the proliferation of both P388 cells and MNCBMs, with IC₅₀ values of 927 and 1911 μg/mL, respectively, but reduced the viability and induced the apoptosis of only leukemia cells. The LD₅₀ was higher than 5000 mg/kg, and this concentration did not alter the blood chemistry or cell count but doubled the mitotic index in the bone marrow. The HPLC showed the presence of cucurbitacins, phloridzin, naringenin, phloretin, apigenin, and gallic, chlorogenic, vanillic, p-hydroxybenzoic, caffeic, and p-coumaric acids.

DISCUSSION AND CONCLUSION

Sechium edule var. nigrum spinosum contains bioactive compounds that explain the antiproliferative and nutraceutical activities, and its lack of physiological side effects constitutes an added value to a widely consumed vegetable.

Ficus virens proanthocyanidins induced apoptosis in breast cancer cells concomitantly ameliorated 5-fluorouracil induced intestinal mucositis in rats

5-Fluorouracil (5-FU) is a commonly used chemotherapeutic agent for breast cancer. However, its use often leads to drug resistance and mucositis. This study aimed to investigate whether proanthocyanidins from Ficus virens possessed anti-breast cancer and anti-mucositis activities. The results showed that the cytotoxic effects of the proanthocyanidins against MDA-MB-231 and MCF-7 breast cancer cells were in the order of stem barks proanthocyanidins (SPAs) > leaves proanthocyanidins > fruits proanthocyanidins. Moreover, SPAs induced apoptosis in both cell lines which were accompanied with an increase in loss of mitochondrial membrane potential, production of reactive oxygen species, Bax to Bcl-2 protein expression ratio, and activated caspase 3. Furthermore, intraperitoneal injection of 5-FU (150 mg/kg body weight) resulted in body weight loss and jejunal injury in the rats while administration of SPAs (100 mg/kg body weight) counteracted these changes. Collectively, our study demonstrated that SPAs induced apoptosis cell death in breast cancer cells while ameliorating the symptoms of intestinal mucositis in rats.Therefore, SPAs merits further exploration as a potential therapeutic agent for breast cancer and chemotherapy-induced mucositis.

Inhibition of histone deacetylase 6 (HDAC6) protects against vincristine-induced peripheral neuropathies and inhibits tumor growth

As cancer is becoming more and more a chronic disease, a large proportion of patients is confronted with devastating side effects of certain anti-cancer drugs. The most common neurological complications are painful peripheral neuropathies. Chemotherapeutics that interfere with microtubules, including plant-derived vinca-alkaloids such as vincristine, can cause these chemotherapy-induced peripheral neuropathies (CIPN). Available treatments focus on symptom alleviation and pain reduction rather than prevention of the neuropathy. The aim of this study was to investigate the potential of specific histone deacetylase 6 (HDAC6) inhibitors as a preventive therapy for CIPN using multiple rodent models for vincristine-induced peripheral neuropathies (VIPN). HDAC6 inhibition increased the levels of acetylated α-tubulin in tissues of rodents undergoing vincristine-based chemotherapy, which correlates to a reduced severity of the neurological symptoms, both at the electrophysiological and the behavioral level. Mechanistically, disturbances in axonal transport of mitochondria is considered as an important contributing factor in the pathophysiology of VIPN. As vincristine interferes with the polymerization of microtubules, we investigated whether disturbances in axonal transport could contribute to VIPN. We observed that increasing α-tubulin acetylation through HDAC6 inhibition restores vincristine-induced defects of axonal transport in cultured dorsal root ganglion neurons. Finally, we assured that HDAC6-inhibition offers neuroprotection without interfering with the anti-cancer efficacy of vincristine using a mouse model for acute lymphoblastic leukemia. Taken together, our results emphasize the therapeutic potential of HDAC6 inhibitors with beneficial effects both on vincristine-induced neurotoxicity, as well as on tumor proliferation.

Long-term toxicity of cisplatin in germ-cell tumor survivors

CONTEXT

Testicular germ-cell tumors (GCT) are highly curable. A multidisciplinary approach, including cisplatin-based chemotherapy has resulted in cure in the majority of patients with GCT. Thus, the life expectancy of survivors will extend to many decades post-diagnosis. Late treatment toxicities associated with cisplatin-based chemotherapy may impact their future health.

OBJECTIVE

To systematically evaluate evidence regarding the long-term toxicity of cisplatin in GCT survivors.

EVIDENCE ACQUISITION

We carried out a critical review of PubMed/Medline in February 2017 according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. Identified reports were reviewed according to the Consolidated Standards of Reporting Trials (CONSORT) criteria. Eighty-three publications were selected for inclusion in this analysis.

EVIDENCE SYNTHESIS

Included reports evaluated long-term toxicities of cisplatin-based chemotherapy in GCT survivors. Studies reporting neuro- and ototoxicity, secondary malignancies, cardiovascular, renal and pulmonary toxicities, hypogonadism and infertility were found. Seven studies (8%) reported genetic underpinnings of long-term toxicities and 3 (4%) and 14 (19%) studies correlated long-term toxicities with circulating platinum levels and cumulative dose of cisplatin, respectively. Significant risks for long-term toxicities associated with cisplatin and platinum-based regimens were reported. The cumulative dose of cisplatin and circulating platinum were reported as risk factors. Several single-nucleotide polymorphisms identified patients susceptible to cisplatin compared with wild-type individuals.

CONCLUSIONS

GCT survivors cured with cisplatin-based chemotherapy are at risk for long-term side-effects. Detection of single-nucleotide polymorphisms could be a valuable tool for predicting long-term toxicities.

PATIENT SUMMARY

Herein, this article summarizes the available evidence of long-term toxicity of cisplatin-based chemotherapy in GCT survivors and provide insights from Indiana University.

Deciphering metabolic rewiring in breast cancer subtypes

Metabolic reprogramming, an emerging hallmark of cancer, is observed in breast cancer. Breast cancer cells rewire their cellular metabolism to meet the demands of survival, proliferation, and invasion. However, breast cancer is a heterogeneous disease, and metabolic rewiring is not uniform. Each subtype of breast cancer displays distinct metabolic alterations. Here, we focus on unique metabolic reprogramming associated with subtypes of breast cancer, as well as common features. Therapeutic opportunities based on subtype-specific metabolic alterations are also discussed. Through this discussion, we aim to provide insight into subtype-specific metabolic rewiring and vulnerabilities that have the potential to better guide therapy and improve outcomes for patients.

Charcot-Marie-Tooth hereditary neuropathy revealed after administration of docetaxel in advanced breast cancer

Charcot-Marie-Tooth (CMT) neuropathy is the most common hereditary cause of neuropathy. Diagnosis is usually not made during the childhood but in adolescence or late adulthood. It is reported in the literature that some neurotoxic chemotherapeutical agents can reveal an asymptomatic CMT IA hereditary neuropathy. To our knowledge, we report here the first case of CMT IA revealed in a 55-year-old woman after the administration of docetaxel/trastuzumab/pertuzumab for metastatic breast cancer. This case stresses again the necessity to obtain a complete personal and familial anamnesis and to perform a neurologic examination before the administration of neurotoxic chemotherapeutical agents to prevent the clinical expression of these hereditary neuropathies.

Magnetic Nanoparticles: From Design and Synthesis to Real World Applications

The increasing number of scientific publications focusing on magnetic materials indicates growing interest in the broader scientific community. Substantial progress was made in the synthesis of magnetic materials of desired size, morphology, chemical composition, and surface chemistry. Physical and chemical stability of magnetic materials is acquired by the coating. Moreover, surface layers of polymers, silica, biomolecules, etc. can be designed to obtain affinity to target molecules. The combination of the ability to respond to the external magnetic field and the rich possibilities of coatings makes magnetic materials universal tool for magnetic separations of small molecules, biomolecules and cells. In the biomedical field, magnetic particles and magnetic composites are utilized as the drug carriers, as contrast agents for magnetic resonance imaging (MRI), and in magnetic hyperthermia. However, the multifunctional magnetic particles enabling the diagnosis and therapy at the same time are emerging. The presented review article summarizes the findings regarding the design and synthesis of magnetic materials focused on biomedical applications. We highlight the utilization of magnetic materials in separation/preconcentration of various molecules and cells, and their use in diagnosis and therapy.

Does "OPTINAB" strategy ("stop-and-go") work in treatment of advanced pancreatic cancer (APC) with nab-paclitaxel-gemcitabine?

BACKGROUND

MPACT demonstrated a survival benefit of nab-paclitaxel plus gemcitabine versus gemcitabine in advanced pancreatic cancer (APC). However, sensory peripheral neuropathy is a dose-limiting toxicity and neuromodulators have shown limited, if any activity in ameliorating neuropathy. In colorectal cancer, the OPTIMOX ("stop-and-go") approach offered a strategy to reduce neuropathy. No data exist to support this strategy for nab-paclitaxel in APC.

METHODS

Retrospective study of APC patients who developed grade 3 neuropathy during nab-paclitaxel plus gemcitabine was done. Nab-paclitaxel was held and then reinstituted upon radiological or tumor marker progression. Duration of disease control (DCC) was measured. We named this strategy "OPTINAB".

RESULTS

Seven patients out of 27 (25%) developed grade 3 neuropathy after an average of 4.2 months; nab-paclitaxel was suspended while gemcitabine was continued. Maintenance gemcitabine continued for a mean of 2.8 months. Upon progression (radiologic or CA19-9) nab-paclitaxel was re-instituted with gemcitabine. One patient could not tolerate nab-paclitaxel due to worsening of neuropathy while other six continued the combo with mean progression-free survival 2 (PFS2) of 2.2 months. The six patients continued nab-paclitaxel for a mean of PFS2 of 2.2 months (range 1-4 months). Nab-paclitaxel resulted in improvement of an average DDC with an average of (7.0 + 2.2 =) 8.2 months (range 8-13 months). Average overall survival for this group was 11.7 months (range 9.5-17 months). Reintroduction of nab-paclitaxel resulted in an average DDC of 9.4 months. Average overall survival (OS) for this group was 11.7 months.

CONCLUSIONS

"OPTINAB" approach improved PFS2 in these patients and was feasible as majority of the patient tolerated nab-paclitaxel. Although it is a small study, it supports the need for a randomized, prospective study to test the concept of "OPTINAB".

Spinal Metastatic Disease: A Review of the Role of the Multidisciplinary Team

Historically, a simple approach centered on palliation was applicable to the majority of patients with metastatic spinal disease. With advances in diagnosis and treatment, a more complicated algorithm has devolved requiring a multidisciplinary approach with institutional commitment and support. We performed a database review including pertinent articles exploring the multidisciplinary management of spinal metastatic disease. The wide variation in clinical presentation and tumor response to treatment necessitates a multidisciplinary approach that integrates the diagnosis and treatment of the cancer, symptom management, and rehabilitation for optimal care of patients with spinal metastases. Advances in the field of radiology have led to earlier and more focused diagnosis of spinal metastasis and acts to guide therapy. Advances in surgical techniques, neurophysiologic monitoring, and anesthetic expertise have allowed surgeons to perform more extensive procedures leading to improved outcomes and reduced morbidity. Radiation oncology input that is essential as external beam radiation therapy can provide significant pain relief. Non-operative measures may include bisphosphonate infusions, management of complications (e.g. hypercalcemia of malignancy), monoclonal antibody infusions, and chemotherapy if indicated in the treatment of the primary malignancy. Input from psychology services is necessary to address the biopsychosocial ramifications of spinal metastasis. Allied health professionals in the form of physiotherapists, social workers, and dieticians also contribute in maximizing patients' quality of life and well-being.

Cisplatin-induced mitochondrial dysfunction is associated with impaired cognitive function in rats

PURPOSE

Chemotherapy-related cognitive impairment (CRCI) is commonly reported following the administration of chemotherapeutic agents and comprises a wide variety of neurological problems. No effective treatments for CRCI are currently available. Here we examined the mechanisms involving cisplatin-induced hippocampal damage following cisplatin administration in a rat model and in cultured rat hippocampal neurons and neural stem/progenitor cells (NSCs). We also assessed the protective effects of the antioxidant, N-acetylcysteine in mitigating these damages.

EXPERIMENTAL DESIGN

Adult male rats received 6mg/kg cisplatin in the acute studies. In chronic studies, rats received 5mg/kg cisplatin or saline injections once per week for 4 weeks. N-acetylcysteine (250mg/kg/day) or saline was administered for five consecutive days during cisplatin treatment. Cognitive testing was performed 5 weeks after treatment cessation. Cisplatin-treated cultured hippocampal neurons and NSCs were examined for changes in mitochondrial function, oxidative stress production, caspase-9 activation, and neuronal dendritic spine density.

RESULTS

Acute cisplatin treatment reduced dendritic branching and spine density, and induced mitochondrial degradation. Rats receiving the chronic cisplatin regimen showed impaired performance in contextual fear conditioning, context object discrimination, and novel object recognition tasks compared to controls. Cisplatin induced mitochondrial DNA damage, impaired respiratory activity, increased oxidative stress, and activated caspase-9 in cultured hippocampal neurons and NSCs. N-acetylcysteine treatment prevented free radical production, ameliorated apoptotic cellular death and dendritic spine loss, and partially reversed the cisplatin-induced cognitive impairments.

CONCLUSIONS

Our results suggest that mitochondrial dysfunction and increased oxidative stress are involved in cisplatin-induced cognitive impairments. Therapeutic agents, such as N-acetylcysteine, may be effective in mitigating the deleterious effects of cisplatin.

Predictors of cognitive decline in people with cancer undergoing chemotherapy

PURPOSE

The purpose of this study was to investigate the impact of demographic factors, disease/treatment-related factors, and psychological factors on cognitive function.

METHOD

A cross-sectional study was conducted. Participants were recruited from the oncology inpatient units of two hospitals. A convenience sample of 175 patients with cancer who underwent chemotherapy were recruited. The Everyday Cognition Scale (ECog), the Korean version of the Mini Mental State Examination (K-MMSE), Functional Assessment of Cancer Therapy-Fatigue (FACT-F) scale, Hospital Anxiety and Depression Scale (HADS), and a questionnaire to collect information about demographic, disease, and treatment information were completed.

RESULTS

More participants showed a mild decline in cognitive function and self-reported cognitive decline (39.4%) than had objectively confirmed decline (20%). Notably, 53.7-62.9% of the participants showed memory loss and a decline in divided attention. Demographic factors (age, sex), disease/treatment-related factors (chemotherapy cycles, fatigue), and psychological factors (depression) were predictors of cognitive decline in 49.6% of participants.

CONCLUSIONS

Old age and cumulative chemotherapy cycles were the main influential factors for objectively confirmed cognitive decline, and fatigue was the most common predictor of self-reported cognitive decline. Depression was one of the predictors of perceived cognitive decline, but it was not significant for objectively measured cognitive function. Thus, treatment-related factors such as fatigue had a greater impact on cognitive decline than psychological factors.