North Central Cancer Treatment Group/Alliance trial N08CA-the use of glutathione for prevention of paclitaxel/carboplatin-induced peripheral neuropathy: a phase 3 randomized, double-blind, placebo-controlled study

Targeting dorsal root ganglia for chemotherapy-induced peripheral neuropathy: from bench to bedside

Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating condition affecting an increasing number of cancer survivors worldwide. However, insights into its pathophysiology and availability of effective therapies remain lacking. Dorsal root ganglia (DRG) have been studied as a key component of chemotherapeutic drug toxicity and a potential therapeutic target for CIPN treatment. This comprehensive review aims to synthesize, summarize, and correlate the results of both preclinical and clinical studies relevant to the pathophysiology and management of CIPN in relation to the DRG. Design: Review. A thorough literature search was conducted using the terms 'dorsal root ganglion' and 'chemotherapy-induced peripheral neuropathy', along with appropriate variations. Searched databases included PubMed, EMBASE, Medline, Cochrane Library, Wiley Library, and Web of Science. Inclusion criteria targeted all English language, peer-reviewed original research from the inception of these databases to the present year. Review articles, book chapters, and other nonoriginal publications were excluded. Of 134 relevant studies identified, the majority were preclinical studies elucidating how various chemotherapeutic agents, especially taxanes, disrupt neurotransmission, inflammatory processes, and apoptotic pathways within sensory neurons of DRG. Not only do these effects correlate with the presentation of CIPN, but their disruption has also been shown to reduce CIPN symptoms in preclinical models. However, clinical studies addressing DRG interventions are very limited in number and scope at this time. These results reveal various pathways within DRG that may be effective targets for CIPN treatment. While limited, clinical studies do offer promise in the utility of DRG neuromodulation in managing painful CIPN. In the future, clinical trials are needed to assess interventions aimed at these neuronal and nonneuronal pathological targets to better treat this complex condition.

Chemotherapy-Induced Peripheral Neuropathy: A Recent Update on Pathophysiology and Treatment

Chemotherapy-induced peripheral neuropathy (CIPN) is a major long-lasting side effect of some chemotherapy drugs, which threatens cancer survival rate. CIPN mostly affects sensory neurons and occasionally motor neurons, causing numbness, tingling, discomfort, and burning pain in the upper and lower extremities. The pathophysiology of CIPN is not completely understood; however, it is believed that chemotherapies induce peripheral neuropathy via directly damaging mitochondria, impairing the function of ion channels, triggering immunological mechanisms, and disrupting microtubules. The treatment of CIPN is a medical challenge, and there are no approved pharmacological options. Currently, duloxetine and other antidepressants, antioxidant, anti-inflammatory, and ion-channel targeted therapies are commonly used in clinics to relieve the symptoms of CIPN. Several other types of drugs, such as cannabinoids, sigma-1 receptor antagonists, and nicotinamides ribose, are being evaluated in preclinical and clinical studies. This paper summarizes the information related to the physiology of CIPN and medicines that could be used for treating this condition.

Targeting therapy-induced senescence as a novel strategy to combat chemotherapy-induced peripheral neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is a treatment-limiting adverse effect of anticancer therapy that complicates the lifestyle of many cancer survivors. There is currently no gold-standard for the assessment or management of CIPN. Subsequently, understanding the underlying mechanisms that lead to the development of CIPN is essential for finding better pharmacological therapy. Therapy-induced senescence (TIS) is a form of senescence that is triggered in malignant and non-malignant cells in response to the exposure to chemotherapy. Recent evidence has also suggested that TIS develops in the dorsal root ganglia of rodent models of CIPN. Interestingly, several components of the senescent phenotype are commensurate with the currently established primary processes implicated in the pathogenesis of CIPN including mitochondrial dysfunction, oxidative stress, and neuroinflammation. In this article, we review the literature that supports the hypothesis that TIS could serve as a holistic mechanism leading to CIPN, and we propose the potential for investigating senotherapeutics as means to mitigate CIPN in cancer survivors.

Chemotherapy-Induced Peripheral Neuropathy: Diagnosis, Agents, General Clinical Presentation, and Treatments

PURPOSE OF REVIEW

This review aims to discuss pathophysiology, diagnosis, clinical presentation, and treatment of chemotherapy-induced peripheral neuropathy. Agent-specific presentation and pathophysiology is also being discussed.

RECENT FINDINGS

As new systemic oncological treatments continue to be developed, the number of cancer survivors continues to grow. Survivors are living longer with the long-term side effects of oncological treatments. We reviewed the pathophysiology of agent-specific chemotherapy-induced peripheral neuropathy and the updates in its treatment and preventative tools. Chemotherapy-induced peripheral neuropathy is a debilitating long-term side effect that often impairs cancer survivors' function and quality of life. The increasing life expectancy of cancer survivors has resulted in increased prevalence of this condition. Understanding its intricacies can provide physicians with better treatment tools and research opportunities to develop or identify new therapeutic agents.

Efficacy of electroacupuncture in the treatment of peripheral neuropathy caused by Utidelone: Study protocol for a randomized controlled trial

Introduction

Utidelone (UTD1) is a new chemotherapeutic drug for recurrent or metastatic breast cancer. However, it usually leads to severe peripheral neuropathy (PN) and causes numbness of the hands and feet and significant pain in patients' life. Electroacupuncture (EA) is considered beneficial in improving PN and relieving numbness of the hands and feet. This trial aims to evaluate the therapeutic effect of EA on PN caused by UTD1 in patients with advanced breast cancer.

Methods and analysis

This study is a prospective randomized controlled trial. A total of 70 patients with PN caused by UTD1 will be randomly assigned to the EA treatment group and the control group in a ratio of 1:1. The patients in the EA treatment group will receive 2 Hz EA three times a week for 4 weeks. The patients in the control group will take mecobalamin (MeCbl) tablets orally, one tablet each, three times a day for 4 weeks. The main outcome measures will be the evaluation scale of peripheral neurotoxicity of chemotherapeutic drugs according to the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-CIPN 20-item (EORTC QLQ-CIPN20) and the peripheral neurotoxicity assessment rating according to NCI CTCAE version 5.0. Secondary outcomes will be the quality of life scale according to the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire (EORTC QLQ-C30). The results will be evaluated at baseline, post-treatment phase, and follow-up. All major analyses will be based on the intention-to-treat principle.

Ethics and dissemination

This protocol was approved by the Medical Ethics Committee of Zhejiang Cancer Hospital on 26 July 2022. The license number is IRB-2022-425. This study will provide clinical efficacy data on EA in the treatment of PN caused by UTD1 and will help to prove whether EA is an effective and safe therapy. The study results will be shared with healthcare professionals through the publication of manuscripts and conference reports.

Trial registration number

ChiCTR2200062741.

Paclitaxel Inhibits KCNQ Channels in Primary Sensory Neurons to Initiate the Development of Painful Peripheral Neuropathy

Cancer patients undergoing paclitaxel infusion usually experience peripheral nerve degeneration and serious neuropathic pain termed paclitaxel-induced peripheral neuropathy (PIPN). However, alterations in the dose or treatment schedule for paclitaxel do not eliminate PIPN, and no therapies are available for PIPN, despite numerous studies to uncover the mechanisms underlying the development/maintenance of this condition. Therefore, we aimed to uncover a novel mechanism underlying the pathogenesis of PIPN. Clinical studies suggest that acute over excitation of primary sensory neurons is linked to the pathogenesis of PIPN. We found that paclitaxel-induced acute hyperexcitability of primary sensory neurons results from the paclitaxel-induced inhibition of KCNQ potassium channels (mainly KCNQ2), found abundantly in sensory neurons and axons. We found that repeated application of XE-991, a specific KCNQ channel blocker, induced PIPN-like alterations in rats, including mechanical hypersensitivity and degeneration of peripheral nerves, as detected by both morphological and behavioral assays. In contrast, genetic deletion of KCNQ2 from peripheral sensory neurons in mice significantly attenuated the development of paclitaxel-induced peripheral sensory fiber degeneration and chronic pain. These findings may lead to a better understanding of the causes of PIPN and provide an impetus for developing new classes of KCNQ activators for its therapeutic treatment.

Emerging Approaches for the Management of Chemotherapy-Induced Peripheral Neuropathy (CIPN): Therapeutic Potential of the C5a/C5aR Axis

Chemotherapy-induced peripheral neuropathy (CIPN) is the most common neurologic complication of chemotherapy, resulting in symptoms like pain, sensory loss, and numbness in the hands and feet that cause lots of uneasiness in patients with cancer. They often suffer from pain so severe that it interrupts the treatment, thus invalidating the entire chemotherapy-based healing process, and significantly reducing their quality of life. In this paper, we underline the role of the complement system in CIPN, highlighting the relevance of the C5a fragment and its receptor C5aR1, whose activation is thought to be involved in triggering a cascade of events that can lead to CIPN onset. Recent experimental data showed the ability of docetaxel and paclitaxel to specifically bind and activate C5aR1, thus shining light on one of the molecular mechanisms by which taxanes may activate a cascade of events leading to neuropathy. According to these new evidence, it was possible to suggest new mechanisms underlying the pathophysiology of CIPN. Hence, the C5a/C5aR1 axis may represent a new target for CIPN treatment, and the use of C5aR1 inhibitors can be proposed as a potential new therapeutic option to manage this high unmet medical need.

Paclitaxel binds and activates C5aR1: A new potential therapeutic target for the prevention of chemotherapy-induced peripheral neuropathy and hypersensitivity reactions

Chemotherapy-induced peripheral neuropathy (CIPN) and hypersensitivity reactions (HSRs) are among the most frequent and impairing side effects of the antineoplastic agent paclitaxel. Here, we demonstrated that paclitaxel can bind and activate complement component 5a receptor 1 (C5aR1) and that this binding is crucial in the etiology of paclitaxel-induced CIPN and anaphylaxis. Starting from our previous data demonstrating the role of interleukin (IL)-8 in paclitaxel-induced neuronal toxicity, we searched for proteins that activate IL-8 expression and, by using the Exscalate platform for molecular docking simulations, we predicted the high affinity of C5aR1 with paclitaxel. By in vitro studies, we confirmed the specific and competitive nature of the C5aR1-paclitaxel binding and found that it triggers intracellularly the NFkB/P38 pathway and c-Fos. In F11 neuronal cells and rat dorsal root ganglia, C5aR1 inhibition protected from paclitaxel-induced neuropathological effects, while in paclitaxel-treated mice, the absence (knock-out mice) or the inhibition of C5aR1 significantly ameliorated CIPN symptoms-in terms of cold and mechanical allodynia-and reduced the chronic pathological state in the paw. Finally, we found that C5aR1 inhibition can counteract paclitaxel-induced anaphylactic cytokine release in macrophages in vitro, as well as the onset of HSRs in mice. Altogether these data identified C5aR1 as a key mediator and a new potential pharmacological target for the prevention and treatment of CIPN and HSRs induced by paclitaxel.

Characterization of Patients With and Without Painful Peripheral Neuropathy After Receiving Neurotoxic Chemotherapy: Traditional Quantitative Sensory Testing vs C-Fiber and Aδ-Fiber Selective Diode Laser Stimulation

Painful chemotherapy induced peripheral neuropathy (CIPN) is a common complication of chemotherapy with drugs such as taxanes and platinum compounds. Currently, no methods are available for early detection of sensory changes that are associated with painful CIPN, nor are there biomarkers that are specific to painful CIPN. This study aimed to compare Diode Laser fiber type-selective stimulator (DLss), a method to selectively stimulate cutaneous C and Aδ fibers, to traditional quantitative sensory testing (QST) in determining psychophysical differences between patients with painful CIPN and a control group. Sensory testing was performed on the dorsal mid-foot of 20 patients with painful neuropathy after taxane- or platinum-based chemotherapy, and 20 patients who received similar neurotoxic chemotherapy, without painful CIPN. In a multivariable analysis, C-fiber to Aδ fiber detection threshold ratio, measured by DLss, was significantly different between the groups (P <.05). While QST parameters such as warmth detection threshold were different between the groups in univariate analyses, these findings were likely attributable to group differences in patient age and cumulative chemotherapy dose. PERSPECTIVE: In this study, fiber-specific DLss test showed potential in identifying sensory changes that are specific for painful neuropathy, encouraging future testing of this approach as a biomarker for early detection of painful CIPN. TRIAL REGISTRATION: The study was approved by the Washington University Institutional Review Board (#201807162) and registered at ClinicalTrials.gov (NCT03687970).

Pharmacogenomics of cisplatin-induced neurotoxicities: Hearing loss, tinnitus, and peripheral sensory neuropathy

PURPOSE

Cisplatin is a critical component of first-line chemotherapy for several cancers, but causes peripheral sensory neuropathy, hearing loss, and tinnitus. We aimed to identify comorbidities for cisplatin-induced neurotoxicities among large numbers of similarly treated patients without the confounding effect of cranial radiotherapy.

METHODS

Utilizing linear and logistic regression analyses on 1680 well-characterized cisplatin-treated testicular cancer survivors, we analyzed associations of hearing loss, tinnitus, and peripheral neuropathy with nongenetic comorbidities. Genome-wide association studies and gene-based analyses were performed on each phenotype.

RESULTS

Hearing loss, tinnitus, and peripheral neuropathy, accounting for age and cisplatin dose, were interdependent. Survivors with these neurotoxicities experienced more hypertension and poorer self-reported health. In addition, hearing loss was positively associated with BMIs at clinical evaluation and nonwork-related noise exposure (>5 h/week). Tinnitus was positively associated with tobacco use, hypercholesterolemia, and noise exposure. We observed positive associations between peripheral neuropathy and persistent vertigo, tobacco use, and excess alcohol consumption. Hearing loss and TXNRD1, which plays a key role in redox regulation, showed borderline significance (p = 4.2 × 10^-6 ) in gene-based analysis. rs62283056 in WFS1 previously found to be significantly associated with hearing loss (n = 511), was marginally significant in an independent replication cohort (p = 0.06; n = 606). Gene-based analyses identified significant associations between tinnitus and WNT8A (p = 2.5 × 10^-6 ), encoding a signaling protein important in germ cell tumors.

CONCLUSIONS

Genetics variants in TXNRD1 and WNT8A are notable risk factors for hearing loss and tinnitus, respectively. Future studies should investigate these genes and if replicated, identify their potential impact on preventive strategies.

A Systematic Review and Meta-Analysis of the Effectiveness of Neuroprotectants for Paclitaxel-Induced Peripheral Neuropathy

Background

Paclitaxel-induced peripheral neuropathy (PIPN) is a disabling side effect of paclitaxel with few effective preventive strategies. We aim to determine the efficacy of pharmacological and non-pharmacological neuroprotective interventions in preventing PIPN incidence.

Methods

Biomedical literature databases were searched from years 2000 to 2021 for trials comparing neuroprotective interventions and control. Meta-analysis was performed using the random-effects model. The primary outcome was the incidence of PIPN.

Results

Of 24 relevant controlled trials, 14 were eligible for meta-analysis. Pooled results from seven non-pharmacological trials were associated with a statistically significant 48% relative reduction of PIPN risk with low heterogeneity. Conversely, pooled results from six pharmacological trials were associated with a significant 20% relative reduction of PIPN risk with moderate heterogeneity. Both pharmacological and non-pharmacological approaches appear effective in reducing PIPN incidence in the treatment arm compared to control (pooled RR < 1).

Conclusion

Current evidence suggests that both interventions may reduce PIPN risk. Non-pharmacological interventions appear more effective than pharmacological interventions.

Chemotherapy-Induced Peripheral Neuropathy: Epidemiology, Pathomechanisms and Treatment

PURPOSE

This review provides an update on the current clinical, epidemiological and pathophysiological evidence alongside the diagnostic, prevention and treatment approach to chemotherapy-induced peripheral neuropathy (CIPN).

FINDINGS

The incidence of cancer and long-term survival after treatment is increasing. CIPN affects sensory, motor and autonomic nerves and is one of the most common adverse events caused by chemotherapeutic agents, which in severe cases leads to dose reduction or treatment cessation, with increased mortality. The primary classes of chemotherapeutic agents associated with CIPN are platinum-based drugs, taxanes, vinca alkaloids, bortezomib and thalidomide. Platinum agents are the most neurotoxic, with oxaliplatin causing the highest prevalence of CIPN. CIPN can progress from acute to chronic, may deteriorate even after treatment cessation (a phenomenon known as coasting) or only partially attenuate. Different chemotherapeutic agents share both similarities and key differences in pathophysiology and clinical presentation. The diagnosis of CIPN relies heavily on identifying symptoms, with limited objective diagnostic approaches targeting the class of affected nerve fibres. Studies have consistently failed to identify at-risk cohorts, and there are no proven strategies or interventions to prevent or limit the development of CIPN. Furthermore, multiple treatments developed to relieve symptoms and to modify the underlying disease in CIPN have failed.

IMPLICATIONS

The increasing prevalence of CIPN demands an objective approach to identify at-risk patients in order to prevent or limit progression and effectively alleviate the symptoms associated with CIPN. An evidence base for novel targets and both pharmacological and non-pharmacological treatments is beginning to emerge and has been recognised recently in publications by the American Society of Clinical Oncology and analgesic trial design expert groups such as ACTTION.

Lithium and preventing chemotherapy-induced peripheral neuropathy in breast cancer patients: a placebo-controlled randomized clinical trial

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse effect of some chemotherapy regimens. Lithium has been suggested for CIPN in some animal studies. We aimed to study lithium's preventive effect on CIPN in breast cancer patients treated with taxanes and platinum-based medications.

METHOD

A double-blind placebo-controlled randomized clinical trial (RCT) was implemented on 36 breast cancer patients in two equal-size groups by block randomization. Participants in both groups consumed daily tablets, either placebo or lithium (300 mg), for 5 days in each course of chemotherapy. The tablets were prescribed 1 day before the start of chemotherapy. The electromyography (EMG) and nerve-conduction-velocity (NCV) tests were achieved before the first chemotherapy, 3 and 9 months after the treatment. The changes and signs or symptoms of CIPN, such as numbness, tingling, freezing, sensitivity to touch, muscle weakness, fibrillation, and knee and elbow reflex disorders, were recorded by examination. The trend of outcome changes was compared between two groups during the 9 months of study.

RESULTS

In both groups, neurologic signs and symptoms were exacerbated during the first 3 months and improved up to the ninth month of study. Results showed significant changes of all EMG-NCV variables during the 9 months of research in each group (P < 0.001), but the interaction of time and group effect was not significant in none of those indices. All symptoms changed significantly over the study time (P < 0.001) without significant statistical difference between the two groups (P=0.352). No side effect was found during the study.

CONCLUSION

The study showed that 300 mg lithium prescription once daily for 5 days might not effectively prevent CIPN in breast cancer patients. Evaluation of lithium effect on CIPN on different cancers in future studies is suggested.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials IRCT20160813029327N10 .  Registration date: May 16, 2018.

Clinical significance of SIRT3 and inflammatory factors in multiple myeloma patients with bortezomib-induced peripheral neuropathy: a cohort study

The present study aimed to investigate the role of SIRT3 and inflammatory factors in bortezomib-induced peripheral neuropathy (PN). This prospective observational cohort study included a total of 159 patients of multiple myeloma patients during June 2016 to June 2019. All patients received the strategy of bortezomib and dexamethasone and were further divided into the PN group and the non-PN group. Serum SIRT3, CRP, IL-6 and TNF-α levels were measured by enzyme-linked immunosorbent assay (ELISA). During the study period, 76 (47.8%) patients developed PN. The inflammatory factors all gradually decreased and SIRT3 levels were gradually increased after treatment by bortezomib combined with dexamethasone compared with the baseline. The levels of all inflammatory factors were markedly higher, while SIRT3 levels were lower in PN patients compared with the non-PN patients at the same time point after treatment. In PN grade III patients, the serum levels of CRP, IL-6 and TNF-α were significantly higher, while serum levels of SIRT3 were markedly lower than the grade I-II patients. SIRT3 was negatively correlated with CRP, IL-6 and TNF-α. After nursing treatment and reduction of bortezomib dose, the levels of SIRT3 significantly increased, while levels of inflammatory decreased in PN patients with grade III. SIRT3 and inflammatory factors showed the potential for diagnosis of bortezomib-induced PN. Besides, SIRT3, IL-6 and TNF-α were the independent risk factors for MM patients developing PN after treatment of bortezomib. Higher inflammatory factors and lower SIRT3 might be associated with the development of bortezomib-induced PN in multiple myeloma patients, which might be reversed by decreased bortezomib dose and proper nursing treatment.

Chemotherapy-induced peripheral neuropathy and rehabilitation: A review

Chemotherapy-induced peripheral neuropathy (CIPN) is a common complication after chemotherapy that can damage the sensory, motor, autonomic, or cranial nerves in approximately 30%-60% of patients with cancer. CIPN can lead to detrimental dose modifications and/or premature chemotherapy discontinuation due to patient intolerance. The long-term impact of CIPN is particularly challenging and can have a profound impact on the quality of life (QoL) and survivorship. However, this condition is often underdiagnosed. No agents have been established to prevent CIPN. Pre-chemotherapy testing is recommended for high-risk patients. Duloxetine is considered a first-line treatment, whereas gabapentin, pregabalin, tricyclic antidepressants, and topical compounding creams may be used for neuropathic pain control. Home-based, low-to-moderate walking, and resistance exercise during chemotherapy can reduce the severity and prevalence of CIPN symptoms, especially in older patients. Pre-habilitation and rehabilitation should be recommended for all patients receiving cytotoxic chemotherapies. The purpose of this article is to review common chemotherapeutic drugs causing CIPN, risk factors, diagnosis and treatment of CIPN, and evidence of the benefits of rehabilitation.

Preclinical and Clinical Evidence of Therapeutic Agents for Paclitaxel-Induced Peripheral Neuropathy

Paclitaxel is an essential drug in the chemotherapy of ovarian, non-small cell lung, breast, gastric, endometrial, and pancreatic cancers. However, it frequently causes peripheral neuropathy as a dose-limiting factor. Animal models of paclitaxel-induced peripheral neuropathy (PIPN) have been established. The mechanisms of PIPN development have been elucidated, and many drugs and agents have been proven to have neuroprotective effects in basic studies. In addition, some of these drugs have been validated in clinical studies for their inhibitory PIPN effects. This review summarizes the basic and clinical evidence for therapeutic or prophylactic effects for PIPN. In pre-clinical research, many reports exist of neuropathy inhibitors that target oxidative stress, inflammatory response, ion channels, transient receptor potential (TRP) channels, cannabinoid receptors, and the monoamine nervous system. Alternatively, very few drugs have demonstrated PIPN efficacy in clinical trials. Thus, enhancing translational research to translate pre-clinical research into clinical research is important.

Genetic Predictors of Chemotherapy-Induced Peripheral Neuropathy from Paclitaxel, Carboplatin and Oxaliplatin: NCCTG/Alliance N08C1, N08CA and N08CB Study

Chemotherapy-induced peripheral neuropathy (CIPN) is a common and potentially permanent adverse effect of chemotherapeutic agents including taxanes such as paclitaxel and platinum-based compounds such as oxaliplatin and carboplatin. Previous studies have suggested that genetics may impact the risk of CIPN. We conducted genome-wide association studies (GWASs) for CIPN in two independent populations who had completed European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ)-CIPN20 assessments (a CIPN-specific 20-item questionnaire which includes three scales that evaluate sensory, autonomic, and motor symptoms). The study population N08Cx included 692 participants from three clinical trials (North Central Cancer Treatment Group (NCCTG) N08C1, N08CA, and N08CB) who had been treated with paclitaxel, paclitaxel plus carboplatin, or oxaliplatin. The primary endpoint for the GWAS was the change from pre-chemotherapy CIPN20 sensory score to the worse score over the following 18 weeks. Study population The Mayo Clinic Breast Disease Registry (MCBDR) consisted of 381 Mayo Clinic Breast Disease Registry enrollees who had been treated with taxane or platinum-based chemotherapy. The primary endpoint for the GWAS assessed was the earliest CIPN20 sensory score available after the completion of chemotherapy. In multivariate model analyses, chemotherapy regimen (p = 3.0 × 10-8) and genetic ancestry (p = 0.007) were significantly associated with CIPN in the N08Cx population. Only age (p = 0.0004) was significantly associated with CIPN in the MCBDR population. The SNP most associated with CIPN was rs56360211 near PDE6C (p =7.92 × 10-8) in N08Cx and rs113807868 near TMEM150C in the MCBDR (p = 1.27 × 10-8). Due to a lack of replication, we cannot conclude that we identified any genetic predictors of CIPN.

Small extracellular vesicles ameliorate peripheral neuropathy and enhance chemotherapy of oxaliplatin on ovarian cancer

There are no effective treatments for chemotherapy induced peripheral neuropathy (CIPN). Small extracellular vesicles (sEVs) facilitate intercellular communication and mediate nerve function and tumour progression. We found that the treatment of mice bearing ovarian tumour with sEVs derived from cerebral endothelial cells (CEC-sEVs) in combination with a chemo-drug, oxaliplatin, robustly reduced oxaliplatin-induced CIPN by decreasing oxaliplatin-damaged myelination and nerve fibres of the sciatic nerve and significantly amplified chemotherapy of oxaliplatin by reducing tumour size. The combination therapy substantially increased a set of sEV cargo-enriched miRNAs, but significantly reduced oxaliplatin-increased proteins in the sciatic nerve and tumour tissues. Bioinformatics analysis revealed the altered miRNAs and proteins formed two distinct networks that regulate neuropathy and tumour growth, respectively. Intravenously administered CEC-sEVs were internalized by axons of the sciatic nerve and cancer cells. Reduction of CEC-sEV cargo miRNAs abolished the effects of CEC-sEVs on oxaliplatin-inhibited axonal growth and on amplification of the anti-cancer effect in ovarian cancer cells, suggesting that alterations in the networks of miRNAs and proteins in recipient cells contribute to the therapeutic effect of CEC-sEVs on CIPN. Together, the present study demonstrates that CEC-sEVs suppressed CIPN and enhanced chemotherapy of oxaliplatin in the mouse bearing ovarian tumour.

Research design considerations for chronic pain prevention clinical trials: IMMPACT recommendations

Although certain risk factors can identify individuals who are most likely to develop chronic pain, few interventions to prevent chronic pain have been identified. To facilitate the identification of preventive interventions, an IMMPACT meeting was convened to discuss research design considerations for clinical trials investigating the prevention of chronic pain. We present general design considerations for prevention trials in populations that are at relatively high risk for developing chronic pain. Specific design considerations included subject identification, timing and duration of treatment, outcomes, timing of assessment, and adjusting for risk factors in the analyses. We provide a detailed examination of 4 models of chronic pain prevention (ie, chronic postsurgical pain, postherpetic neuralgia, chronic low back pain, and painful chemotherapy-induced peripheral neuropathy). The issues discussed can, in many instances, be extrapolated to other chronic pain conditions. These examples were selected because they are representative models of primary and secondary prevention, reflect persistent pain resulting from multiple insults (ie, surgery, viral infection, injury, and toxic or noxious element exposure), and are chronically painful conditions that are treated with a range of interventions. Improvements in the design of chronic pain prevention trials could improve assay sensitivity and thus accelerate the identification of efficacious interventions. Such interventions would have the potential to reduce the prevalence of chronic pain in the population. Additionally, standardization of outcomes in prevention clinical trials will facilitate meta-analyses and systematic reviews and improve detection of preventive strategies emerging from clinical trials.

Protective effect of the oral administration of cystine and theanine on oxaliplatin-induced peripheral neuropathy: a pilot randomized trial

BACKGROUND

Oxaliplatin, one of the key cytotoxic drugs for colorectal cancer, frequently causes peripheral neuropathy which leads to dose modification and decreased patients' quality of life. However, prophylactic or therapeutic measures have not yet been established. Orally administered amino acids, cystine and theanine, promoted the synthesis of glutathione which was one of the potential candidates for preventing the neuropathy. The aim of this study was to determine whether daily oral administration of cystine and theanine attenuated oxaliplatin-induced peripheral neuropathy (OXLIPN).

METHODS

Twenty-eight colorectal cancer patients who received infusional 5-fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) therapy were randomly and evenly assigned to the cystine and theanine group and the control group. OXLIPN was assessed up to the sixth course using original 7-item questionnaire as well as Common Terminology Criteria for Adverse Events (CTCAE) grading scale.

RESULTS

Neuropathy scores according to our original questionnaire were significantly smaller in the cystine and theanine group at the fourth (p = 0.026), fifth (p = 0.029), and sixth course (p = 0.038). Furthermore, significant differences were also observed in CTCAE neuropathy grades at the fourth (p = 0.037) and the sixth course (p = 0.017). There was one patient in each group who required dose reduction due to OXLIPN. Except for neurotoxicity, no significant differences were noted in the incidence of adverse events, and the total amount of administered oxaliplatin.

CONCLUSION

The results demonstrated the daily oral administration of cystine and theanine attenuated OXLIPN.

Platinum-induced peripheral neurotoxicity: From pathogenesis to treatment

Platinum-induced peripheral neurotoxicity (PIPN) is a common side effect of platinum-based chemotherapy that may cause dose reduction and discontinuation, with oxaliplatin being more neurotoxic. PIPN includes acute neurotoxicity restricted to oxaliplatin, and chronic non-length-dependent sensory neuronopathy with positive and negative sensory symptoms and neuropathic pain in both upper and lower limbs. Chronic sensory axonal neuropathy manifesting as stocking-and-glove distribution is also frequent. Worsening of neuropathic symptoms after completing the last chemotherapy course may occur. Motor and autonomic involvement is uncommon. Ototoxicity is frequent in children and more commonly to cisplatin. Platinum-based compounds result in more prolonged neuropathic symptoms in comparison to other chemotherapy agents. Patient reported outcomes questionnaires, clinical evaluation and instrumental tools offer complementary information in PIPN. Electrodiagnostic features include diffusely reduced/abolished sensory action potentials, in keeping with a sensory neuronopathy. PIPN is dependent on cumulative dose but there is a large variability in its occurrence. The search for additional risk factors for PIPN has thus far yielded no consistent findings. There are currently no neuroprotective strategies to reduce the risk of PIPN, and symptomatic treatment is limited to duloxetine that was found effective in a single phase III intervention study. This review critically examines the pathogenesis, incidence, risk factors (both clinical and pharmacogenetic), clinical phenotype and management of PIPN.

Taxane and epothilone-induced peripheral neurotoxicity: From pathogenesis to treatment

Taxane-induced peripheral neurotoxicity (TIPN) is the most common non-hematological side effect of taxane-based chemotherapy, and may result in dose reductions and discontinuations, having as such a detrimental effect on patients' overall survival. Epothilones share similar mechanism of action with taxanes. The typical TIPN clinical presentation is mainly comprised of numbness and paresthesia, in a stocking-and-glove distribution and may progress more proximally over time, with paclitaxel being more neurotoxic than docetaxel. Motor and autonomic involvement is less common, whereas an acute taxane-induced acute pain syndrome is frequent. Patient reported outcomes questionnaires, clinical evaluation, and instrumental tools offer complementary information in TIPN. Its electrodiagnostic features include reduced/abolished sensory action potentials, and less prominent motor involvement, in keeping with a length-dependent, axonal dying back predominately sensory neuropathy. TIPN is dose-dependent and may be reversible within months after the end of chemotherapy. The single and cumulative delivered dose of taxanes is considered the main risk factor of TIPN development. Apart from the cumulative dose, other risk factors for TIPN include demographic, clinical, and pharmacogenetic features with several single-nucleotide polymorphisms potentially linked with increased susceptibility of TIPN. There are currently no neuroprotective strategies to reduce the risk of TIPN, and symptomatic treatments are very limited. This review critically examines the pathogenesis, incidence, risk factors (both clinical and pharmacogenetic), clinical phenotype and management of TIPN.

Psychometric Testing of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Chemotherapy-Induced Peripheral Neuropathy 20-Item Scale Using Pooled Chemotherapy-Induced Peripheral Neuropathy Outcome Measures Standardization and Alliance for Clinical Trials in Oncology A151408 Study Data

BACKGROUND

No criterion-standard patient-reported outcome measure of chemotherapy-induced peripheral neuropathy (CIPN) exists.

OBJECTIVES

The aims of this study were to reevaluate the sensitivity, reliability, and validity of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-CIPN (QLQ-CIPN20) measure and suggest possible revisions that could strengthen it.

METHODS

Cross-sectional QLQ-CIPN20 data from 8 European countries (n = 271) were pooled with data from 4 North American multisite CIPN intervention trials (n = 884). The combined sample (N = 1155) included patients with varied cancer diagnoses who had received neurotoxic chemotherapy. Item score ranges, Cronbach's α, and exploratory factor analysis were used to evaluate sensitivity, internal consistency, and structural validity.

RESULTS

Individual item mean scores ranged from 1.21 to 2.34 (SD range, 0.55-1.17). All item scores encompassed the entire 1 to 4 range. We recommend that 4 items be removed because of low item-item score correlations (r < 0.30). On the basis of the remaining 16 items, 88% of the variance was explained by 2 factors whose Cronbach's α coefficients were .90 and .85. However, items lacked conceptual alignment with previously published factor structures.

CONCLUSION

Using a large, diverse sample of European and North American participants, the reduced 16-item QLQ-CIPN20 is sensitive and internally consistent. However, factor analysis results revealed an unstable factor structure.

IMPLICATIONS FOR PRACTICE

The use of a reliable, valid, and sensitive criterion-standard QLQ-CIPN20 variant in clinical practice settings could improve function, quality of life, and CIPN symptom control by facilitating patient reporting and thereby clinician awareness of this underrecognized consequence of cancer therapy.

Randomized controlled trial of cryotherapy to prevent paclitaxel-induced peripheral neuropathy (RU221511I); an ACCRU trial

PURPOSE

This pilot trial aimed to assess if cooling hands and feet with crushed ice during receipt of paclitaxel helps prevent peripheral neuropathy.

METHODS

This prospective, randomized trial compared cryotherapy to standard care in patients initiating paclitaxel weekly x 12. For those on cryotherapy, hands and feet were cooled starting 15 min prior to and ending 15 min after each paclitaxel dose. EORTC QLQ-CIPN20 was completed at baseline, weekly x12, then monthly x6. Area under the curve (AUC) was calculated for subscale scores, adjusting for baseline, and compared between arms (Wilcoxon rank-sum test). Cross-study comparisons used data from 2 prior similarly-conducted neuropathy trials.

RESULTS

Forty-six patients were accrued. Three withdrew and one was ineligible. Of the remaining 42 (21 cryotherapy, 21 control), 39 (19 cryotherapy, 20 control) were analyzable for AUC. Cryotherapy was well tolerated, but the AUC of the CIPN20 sensory scores over 12 weeks of paclitaxel was not found to differ between the study arms (mean difference 3.45, 95% CI -3.13 to 10.02, p = 0.26). However, the control arm of the current trial experienced less neuropathy than did the placebo arms of two previous similar trials. When our cryotherapy arm was compared to the combined control arms from all three trials, the cryotherapy arm had less neuropathy (Wilcoxon Rank-Sum p = 0.01).

CONCLUSION

While there was no difference in CIPN20 scores identified between the 2 study arms in the current phase II trial, further investigation is needed given that the control arm experienced less neuropathy than was expected.

Pharmacological Treatment of Chemotherapy-Induced Neuropathic Pain: PPARγ Agonists as a Promising Tool

Chemotherapy-induced neuropathic pain (CINP) is one of the most severe side effects of anticancer agents, such as platinum- and taxanes-derived drugs (oxaliplatin, cisplatin, carboplatin and paclitaxel). CINP may even be a factor of interruption of treatment and consequently increasing the risk of death. Besides that, it is important to take into consideration that the incidence of cancer is increasing worldwide, including colorectal, gastric, lung, cervical, ovary and breast cancers, all treated with the aforementioned drugs, justifying the concern of the medical community about the patient’s quality of life. Several physiopathological mechanisms have already been described for CINP, such as changes in axonal transport, mitochondrial damage, increased ion channel activity and inflammation in the central nervous system (CNS). Another less frequent event that may occur after chemotherapy, particularly under oxaliplatin treatment, is the central neurotoxicity leading to disorders such as mental confusion, catatonia, hyporeflexia, etc. To date, no pharmacological therapy has shown satisfactory effect in these cases. In this scenario, duloxetine is the only drug currently in clinical use. Peroxisome proliferator-activated receptors (PPARs) belong to the class of nuclear receptors and are present in several tissues, mainly participating in lipid and glucose metabolism and inflammatory response. There are three PPAR isoforms: α, β/δ and γ. PPARγ, the protagonist of this review, is expressed in adipose tissue, large intestine, spleen and neutrophils. This subtype also plays important role in energy balance, lipid biosynthesis and adipogenesis. The effects of PPARγ agonists, known for their positive activity on type II diabetes mellitus, have been explored and present promising effects in the control of neuropathic pain, including CINP, and also cancer. This review focuses largely on the mechanisms involved in chemotherapy-induced neuropathy and the effects of the activation of PPARγ to treat CINP. It is the aim of this review to help understanding and developing novel CINP therapeutic strategies integrating PPARγ signalling.

Protective Role of Epigallocatechin Gallate in a Rat Model of Cisplatin-Induced Cerebral Inflammation and Oxidative Damage: Impact of Modulating NF-κB and Nrf2

Cisplatin is a widely used chemotherapeutic agent in treating various types of cancers. However, it can induce neurotoxicity and nephrotoxicity, limiting its dose and clinical use. Although previous studies indicated the direct link between cisplatin-induced central neurotoxicity and oxidative stress, the exact mechanism is not completely understood. Therefore, herein we investigated the effects of prophylactic and concurrent treatment with (-)-epigallocatechin-3-gallate (EGCG), a natural polyphenolic neuroprotective antioxidant, on cisplatin-induced brain toxicity in rats to delineate its molecular mechanism of action. We found that cisplatin initiated a cascade of genetic, biological, and histopathological changes in the brain cortex, inducing inflammatory cytokines, appearance of scattered inflammatory cells, nitro-oxidative stress, and apoptotic proteins in the cerebral cortex. However, EGCG not only protected against cisplatin-induced inflammatory burden but also ameliorated the induction of nitro-oxidative stress and apoptotic proteins triggered by cisplatin in the cerebral cortex of pre- and co-treated rats with respect to their unprotected counterparts. EGCG anti-inflammatory effect here may be attributed to the downregulation of nuclear factor kappa B (NF-κB). Additionally, this natural polyphenol significantly ameliorated cisplatin-elicited reduction in cerebral cortex brain-derived neurotrophic factor and acetylcholine esterase. Upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream heme oxygenase-1 (HO-1) by EGCG prophylactic and concurrent administration here seems also to play a key role in the protective impact of EGCG against cisplatin toxicity through enhancing total antioxidant capacity. Thus, EGCG can be used as a promising prophylactic adjuvant for preventing the development of brain inflammation and oxidative damage associated with cisplatin chemotherapy.

Chemotherapy-Induced Peripheral Neuropathy: Association With Increased Risk of Falls and Injuries

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating and degenerative side effect of many commonly used chemotherapy agents. Symptoms manifest as sensory and motor neuropathies. CIPN may necessitate chemotherapy dose reduction or discontinuation.

OBJECTIVES

This review intends to summarize literature linking CIPN to an increased risk of falls and injuries and provides recommendations to help maintain patient safety and maximize physical function.

METHODS

A literature search was conducted using MEDLINE®, PubMed®, and ScienceDirect.

FINDINGS

Assessment of CIPN and CIPN-related falls and injuries is vital in preventing related complications, and proper education of oncology nursing staff on CIPN assessment and management is necessary.

Prevention and Management of Chemotherapy-Induced Polyneuropathy

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a severe and common side effect caused by a variety of antineoplastic agents. Approximately 30-40% of patients treated with agents such as taxanes, vinca alkaloids, or platinum derivatives will develop CIPN. CIPN presents predominantly as a sensory axonal neuro(no)pathy with occasional motor and autonomic dysfunction exhibiting considerable variability of clinical symptoms ranging from mild tingling sensation to severe neuropathic pain. Typical symptoms include numbness ("minus symptom"), weakness, and abnormal gait as well as paresthesia and pain ("positive symptoms"). As CIPN symptoms potentially lead to long-term morbidity and can even aggravate after cessation of therapy, patients' quality of life can be tremendously affected. In view of improved breast cancer survival outcomes, the late effects of CIPN are an unmet need in these patients. Therefore, early detection and assessment of first symptoms is important to effectively prevent severe CIPN. Therapeutic options for patients with CIPN are still limited, and pharmacological treatment focuses primarily on reduction or relief of neuropathic pain. CIPN is usually acutely managed by dose reduction or discontinuation of causative chemotherapy, potentially compromising treatment outcome. Currently, there is no causative proven therapy for the prevention of CIPN.

Characterization of Internal Validity Threats to Phase III Clinical Trials for Chemotherapy-Induced Peripheral Neuropathy Management: A Systematic Review

Objective:

The recent American Society of Clinical Oncology (ASCO) Clinical Guidelines for chemotherapy-induced peripheral neuropathy (CIPN) management (48 Phase III trials reviewed) only recommend duloxetine. However, before concluding that a CIPN intervention is ineffective, scientists and clinicians should consider the risk of Type II error in Phase III studies. The purpose of this systematic review was to characterize internal threats to validity in Phase III CIPN management trials.

Methods:

The PubMed, CINAHL, EMBASE^®, and Scopus databases were searched for Phase III clinical trials testing interventions for CIPN management between 1990 and 2018. The key search terms were neoplasms, cancer, neuropathy, and CIPN. Two independent researchers evaluated 24 studies, using a modified Joanna Briggs Institute Checklist for Randomized Control Trials developed by the authors specific for CIPN intervention trials.

Results:

Two studies exhibited minimal or no design flaws. 22/24 Phase III clinical trials for CIPN have two or greater design flaws due to sample heterogeneity, malapropos mechanism of action, malapropos intervention dose, malapropos timing of the outcome measurement, confounding variables, lack of a valid and reliable measurement, and suboptimal statistical validity.

Conclusions:

Numerous CIPN interventions have been declared ineffective based on the results of Phase III trials. However, internal validity threats to numerous studies may have resulted in Type II error and subsequent dismissal of a potentially effective intervention. Patients may benefit from rigorous retesting of several agents (e.g., alpha-lipoic acid, duloxetine, gabapentin, glutathione, goshajinkigan, lamotrigine, nortriptyline, venlafaxine, and Vitamin E) to expand and validate the evidence regarding ASCO's recommendations for CIPN management.

Activation of KCNQ Channels Prevents Paclitaxel-Induced Peripheral Neuropathy and Associated Neuropathic Pain

Paclitaxel-induced peripheral neuropathy (PIPN) and associated neuropathic pain are the most common and serious adverse effects experienced by cancer patients receiving paclitaxel treatment. These effects adversely impact daily activities and consequently the quality of life, sometimes forcing the suspension of treatment and negatively influencing survival. Patients are usually at high risk of developing PIPN if paclitaxel induces acute pain, which strongly suggests that an acute increase in the excitability of nociceptors underlies the chronic alterations of PIPN. KCNQ/Kv7 channels are widely expressed in the primary sensory neurons to modulate their excitability. In the present study, we show that targeting KCNQ/Kv7 channels at an early stage is an effective strategy to attenuate the development of PIPN. We found that paclitaxel did not decrease the expression level of KCNQ/Kv7 channels in the primary sensory neurons as detected by quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and Western blotting. However, retigabine, which is a specific KCNQ/Kv7 channel opener, attenuated significantly the development of PIPN, as shown by both morphologic and behavioral evidence. We also observed that retigabine had no obvious effect on the chemosensitivity of breast cancer cells to paclitaxel. Although retigabine has been approved by the FDA as an anticonvulsant, our study suggests that this drug can be repurposed to attenuate the development of PIPN. PERSPECTIVE: Paclitaxel-induced peripheral neuropathy and associated neuropathic pain are severe and resistant to intervention. The results of our study demonstrated that retigabine (a clinically available medicine) can be used to attenuate the development of paclitaxel-induced peripheral neuropathy.

Rasch model-based testing of the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Chemotherapy-Induced Peripheral Neuropathy (QLQ-CIPN20) using Alliance for Clinical Trials in Oncology (Alliance) A151408 study data

PURPOSE

To test the psychometric properties of the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Chemotherapy-Induced Peripheral Neuropathy (QLQ-CIPN20) using Rasch-based methods.

METHODS

A secondary data analysis was performed using pooled QLQ-CIPN20 data from patients (N = 1008) who had participated in any of four multi-site chemotherapy-induced peripheral neuropathy (CIPN) treatment and prevention trials. QLQ-CIPN20 responses were evaluated using a polytomous Rasch partial credit model. Data were assessed for person-item fit using the chi-square statistic, item scaling based on response proportions, threshold ordering using item characteristic curves and logit threshold locations, differential item response (DIF) (i.e., response bias) using likelihood ratio tests, and unidimensionality using cluster analysis.

RESULTS

A statistically significant chi-square test indicated poor fit of the observed to the expected responses. More than 70% of the respondents reported a complete absence of six symptoms, reflecting significant floor effects and poor item scaling. Disordered/non-ordinal or narrow response thresholds were found for 11 of the 20 items. Item responses were significantly different by gender (p < 0.0001) and chemotherapy type (p < 0.0001). Cluster analysis findings suggest that the QLQ-CIPN20 is a unidimensional scale due to the absence of item clusters.

CONCLUSIONS

Rasch model testing revealed psychometric weaknesses that could be addressed by revising the QLQ-CIPN20's problematic items and response options. Alternatively, perhaps the new gold standard CIPN measurement approach in future intervention trials should involve use of only the best items, which would also allow comparisons across previous trials that utilized the QLQ-CIPN20.

In Search of a Gold Standard Patient-Reported Outcome Measure for Use in Chemotherapy- Induced Peripheral Neuropathy Clinical Trials

Purpose:

To test a reduced version—CIPN15—of the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Chemotherapy-Induced Peripheral Neuropathy scale (QLQ-CIPN20) to establish a possible gold-standard patient-reported outcome measure for chemotherapy-induced peripheral neuropathy (CIPN).

Methods:

Using a prospective, longitudinal, case–control design, patients (n = 121) receiving neurotoxic chemotherapy completed the CIPN15 at baseline and 12 weeks and underwent objective neurological assessment using the 5-item Total Neuropathy Score-Clinical (TNSc). Healthy controls (n = 30) completed the CIPN15 once. Structural validity was evaluated using factor analysis. Because a stable factor structure was not found, a sum score was used to evaluate measures of the CIPN15’s psychometric properties—reliability, validity, sensitivity, and responsiveness—as follows: internal consistency via Cronbach’s α and item–item correlations; test–retest reliability via correlation between 2 CIPN15 scores from each patient; concurrent validity via correlation between CIPN15 and 5-item TNSc scores; contrasting group validity via comparison of CIPN15 scores from patients and healthy controls; sensitivity via descriptive statistics (means, standard deviation, ranges); and responsiveness via Cohen’s d effect size.

Results:

Most patients received single agent oxaliplatin (33.7%), paclitaxel (21.2%), or more than 1 neurotoxic drug concurrently (29.8%). Factor analysis revealed no stable factor structure. Cronbach’s α for the CIPN15 sum score was 0.91 (confidence interval [CI] = 0.89-0.93). Test–retest reliability was demonstrated based on strong correlations between the 2 scores obtained at the 12-week time point (r = 0.86; CI = 0.80-0.90). The CIPN15 and 5-item TNSc items reflecting symptoms (not signs) were moderately correlated (r range 0.57-0.72): concurrent validity. Statistically significant differences were found between patient and healthy control CIPN15 mean scores (P < .0001): contrasting group validity. All items encompassed the full score range but the CIPN15 linearly converted sum score did not: sensitivity. The CIPN15 was responsive based on a Cohen’s d of 0.52 (CI = 0.25-0.79).

Conclusion:

The sum-scored CIPN15 is reliable, valid, sensitive, and responsive when used to assess taxane- and platinum-induced CIPN.

Pain in Platin-Induced Neuropathies: A Systematic Review and Meta-Analysis

Introduction

Platin-induced peripheral neuropathy (PIPN) is a common cause of PN in cancer patients. The aim of this paper is to systematically review the current literature regarding PIPN, with a particular focus on epidemiological and clinical characteristics of painful PIPN, and to discuss relevant management strategies.

Methods

A systematic computer-based literature search was conducted on the PubMed database.

Results

This search strategy resulted in the identification of 353 articles. After the eligibility assessment, 282 articles were excluded. An additional 24 papers were identified by scanning the reference lists. In total, 95 papers met the inclusion criteria and were used for this review. The prevalence of neuropathic symptoms due to acute toxicity of oxaliplatin was estimated at 84.6%, whereas PN established after chemotherapy with platins was estimated at 74.9%. Specifically regarding pain, the reported prevalence of pain due to acute toxicity of oxaliplatin was estimated at 55.6%, whereas the reported prevalence of chronic peripheral neuropathic pain in PIPN was estimated at 49.2%.

Conclusion

Peripheral neuropathy is a common complication in patients receiving platins and can be particularly painful. There is significant heterogeneity among studies regarding the method for diagnosing peripheral neuropathy. Nerve conduction studies are the gold standard and should be performed in patients receiving platins and complaining of neuropathic symptoms post-treatment.

Patient-reported (EORTC QLQ-CIPN20) versus physician-reported (CTCAE) quantification of oxaliplatin- and paclitaxel/carboplatin-induced peripheral neuropathy in NCCTG/Alliance clinical trials

PURPOSE

Clinical practice guidelines on chemotherapy-induced peripheral neuropathy (CIPN) use the NCI Common Terminology Criteria for Adverse Events (CTCAE), while recent clinical trials employ a potentially superior measure, the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-CIPN twenty-item scale (QLQ-CIPN20), a patient-reported outcome (PRO). Practitioners and researchers lack guidance, regarding how QLQ-CIPN20 results relate to the traditional CTCAE during the serial assessment of patients undergoing chemotherapy.

METHODS

Two large CIPN clinical trial datasets (538 patients) pairing QLQ-CIPN20 and CTCAE outcomes were analyzed using a multivariable linear mixed model with QLQ-CIPN20 score as the outcome variable, CTCAE grade as the main effect, and patient as random effect (accounting for internal correlation of serial measures).

RESULTS

The association between QLQ-CIPN20 scores and CTCAE grades was strong (p < 0.0001), whereby patients with higher CTCAE grade had worse QLQ-CIPN20 scores. Some variation of QLQ-CIPN20 scores was observed based on drug, treatment, and cycle. While there was a marked difference in the mean QLQ-CIPN20 scores between CTCAE grades, the ranges of QLQ-CIPN20 scores within each CTCAE grade were large, leading to large overlap in CIPN20 scores across CTCAE grades.

CONCLUSIONS

A strong positive association of QLQ-CIPN20 scores and CTCAE grade provides evidence of convergent validity as well as practical guidance, as to how to quantitatively interpret QLQ-CIPN20 scores at the study level in terms of the traditional CTCAE. The present results also highlight an important clinical caveat, specifically, that conversion of a specific QLQ-CIPN20 score to a specific CTCAE score may not be reliable at the level of an individual patient.

Clinical and Genome-Wide Analysis of Cisplatin-Induced Peripheral Neuropathy in Survivors of Adult-Onset Cancer

Purpose: Our purpose was to characterize the clinical influences, genetic risk factors, and gene mechanisms contributing to persistent cisplatin-induced peripheral neuropathy (CisIPN) in testicular cancer survivors (TCSs).Experimental Design: TCS given cisplatin-based therapy completed the validated EORTC QLQ-CIPN20 questionnaire. An ordinal CisIPN phenotype was derived, and associations with age, smoking, excess drinking, hypertension, body mass index, diabetes, hypercholesterolemia, cumulative cisplatin dose, and self-reported health were examined for 680 TCS. Genotyping was performed on the Illumina HumanOmniExpressExome chip. Following quality control and imputation, 5.1 million SNPs in 680 genetically European TCS formed the input set. GWAS and PrediXcan were used to identify genetic variation and genetically determined gene expression traits, respectively, contributing to CisIPN. We evaluated two independent datasets for replication: Vanderbilt's electronic health database (BioVU) and the CALGB 90401 trial.Results: Eight sensory items formed a subscale with good internal consistency (Cronbach α = 0.88). Variables significantly associated with CisIPN included age at diagnosis (OR per year, 1.06; P = 2 × 10-9), smoking (OR, 1.54; P = 0.004), excess drinking (OR, 1.83; P = 0.007), and hypertension (OR, 1.61; P = 0.03). CisIPN was correlated with lower self-reported health (OR, 0.56; P = 2.6 × 10-9) and weight gain adjusted for years since treatment (OR per Δkg/m2, 1.05; P = 0.004). PrediXcan identified lower expressions of MIDN and RPRD1B, and higher THEM5 expression as associated with CisIPN (P value for each < 5 × 10-6) with replication of RPRD1B meeting significance criteria (Fisher combined P = 0.0089).Conclusions: CisIPN is associated with age, modifiable risk factors, and genetically determined expression level of RPRD1B Further study of implicated genes could elucidate the pathophysiologic underpinnings of CisIPN. Clin Cancer Res; 23(19); 5757-68. ©2017 AACR.

Risk-reduction and treatment of chemotherapy-induced peripheral neuropathy

INTRODUCTION

Chemotherapy-induced peripheral neuropathy (CIPN), a common adverse effect of several chemotherapeutic agents, has a significant impact on quality of life and may even compromise treatment efficacy, requiring chemotherapy dose reduction or discontinuation. CIPN is predominantly related with sensory rather than motor symptoms and the most common related cytotoxic agents are platinum compounds, taxanes and vinca alkaloids. CIPN symptoms may resolve after treatment cessation, but they can also be permanent and continue for years. Areas covered: We present an overview of CIPN pathophysiology, clinical assessment, prevention and treatment identified through a Pubmed search. Expert commentary: No substantial progress has been made in the last few years within the field of prevention and/or treatment of CIPN, in spite of remarkable efforts. Continuous research could expand our knowledge about chemotherapeutic-specific neuropathic pathways and eventually lead to the conception of innovative and targeted agents for the prevention and/or treatment of this debilitating chemotherapy adverse effect.

Ion channels and neuronal hyperexcitability in chemotherapy-induced peripheral neuropathy; cause and effect?

Abstract

Cancer is the second leading cause of death worldwide and is a major global health burden. Significant improvements in survival have been achieved, due in part to advances in adjuvant antineoplastic chemotherapy. The most commonly used antineoplastics belong to the taxane, platinum, and vinca alkaloid families. While beneficial, these agents are frequently accompanied by severe side effects, including chemotherapy-induced peripheral neuropathy (CPIN). While CPIN affects both motor and sensory systems, the majority of symptoms are sensory, with pain, tingling, and numbness being the predominant complaints. CPIN not only decreases the quality of life of cancer survivors but also can lead to discontinuation of treatment, thereby adversely affecting survival. Consequently, minimizing the incidence or severity of CPIN is highly desirable, but strategies to prevent and/or treat CIPN have proven elusive. One difficulty in achieving this goal arises from the fact that the molecular and cellular mechanisms that produce CPIN are not fully known; however, one common mechanism appears to be changes in ion channel expression in primary afferent sensory neurons. The processes that underlie chemotherapy-induced changes in ion channel expression and function are poorly understood. Not all antineoplastic agents directly affect ion channel function, suggesting additional pathways may contribute to the development of CPIN Indeed, there are indications that these drugs may mediate their effects through cellular signaling pathways including second messengers and inflammatory cytokines. Here, we focus on ion channelopathies as causal mechanisms for CPIN and review the data from both pre-clinical animal models and from human studies with the aim of facilitating the development of appropriate strategies to prevent and/or treat CPIN.

[Chemotherapy-induced peripheral neuropathies: an integrative review of the literature]

OBJECTIVE

To identify scientific studies and to deepen the knowledge of peripheral neuropathies induced by chemotherapy antineoplastic, seeking evidence for assistance to cancer patients.

METHOD

Integrative review of the literature conducted in the databases Latin American and Caribbean Health Sciences (LILACS), Scientific Electronic Library Online (SciELO), Medical Literature Analysis (PubMed/MEDLINE), the Cochrane Library and the Spanish Bibliographic Index Health Sciences (IBECS).

RESULTS

The sample consisted of 15 studies published between 2005-2014 that met the inclusion criteria. Studies showed aspects related to advanced age, main symptoms of neuropathy and chemotherapy agents as important adverse effect of neuropathy.

CONCLUSION

We identified a small number of studies that addressed the topic, as well as low production of evidence related to interventions with positive results. It is considered important to develop new studies proposed for the prevention and/or treatment, enabling adjustment of the patient's cancer chemotherapy and consequently better service.

A Systematic Review of the Incidence and Risk Factors for Taxane Acute Pain Syndrome in Patients Receiving Taxane-Based Chemotherapy for Prostate Cancer

Taxane acute pain syndrome (TAPS) is characterized by myalgia and arthralgia starting 24 to 48 hours after taxane-based chemotherapy and lasting ≤ 7 days. Little is known about its incidence and predisposing factors in patients with prostate cancer. A systematic review was performed to identify studies reporting the incidence and risk factors for TAPS in patients receiving taxane-based chemotherapy for prostate cancer. Embase, Ovid Medline, and other nonindexed citations were searched from 1947 to July 7, 2015. Randomized trials and prospective observational studies reporting the outcomes for prostate cancer patients who had received taxane-based chemotherapy were assessed. Four reviewers independently screened the citations and full text reports for data collection. Of 980 citations, 5 studies (2710 patients) met the eligibility criteria. The incidence of myalgia and arthralgia was reported in 4 trials (14%, [29% and 38%], 44.2%, and 46%). TAPS was not reported with cabazitaxel chemotherapy. Clinical risk factors were identified in 4 studies, suggesting that TAPS was numerically more common in the castrate-resistant setting and when concurrent medications (eg, corticosteroids) were not used. Although the TAPS incidence has been poorly reported in clinical practice, the results of the present study suggest that arthralgia and myalgia are a common toxicity in patients with prostate cancer. An improved and universal definition of TAPS, patient-directed reporting of TAPS, and improved standardized assessments are needed to better identify patients at the greatest risk of experiencing TAPS and improving patient care.

Chemotherapy-induced peripheral neuropathy: an update on the current understanding

Chemotherapy-induced peripheral neuropathy is a common side effect of selected chemotherapeutic agents. Previous work has suggested that patients often under report the symptoms of chemotherapy-induced peripheral neuropathy and physicians fail to recognize the presence of such symptoms in a timely fashion. The precise pathophysiology that underlies chemotherapy-induced peripheral neuropathy, in both the acute and the chronic phase, remains complex and appears to be medication specific. Recent work has begun to demonstrate and further clarify potential pathophysiological processes that predispose and, ultimately, lead to the development of chemotherapy-induced peripheral neuropathy. There is increasing evidence that the pathway to neuropathy varies with each agent. With a clearer understanding of how these agents affect the peripheral nervous system, more targeted treatments can be developed in order to optimize treatment and prevent long-term side effects.

Research design considerations for chronic pain prevention clinical trials: IMMPACT recommendations

Although certain risk factors can identify individuals who are most likely to develop chronic pain, few interventions to prevent chronic pain have been identified. To facilitate the identification of preventive interventions, an IMMPACT meeting was convened to discuss research design considerations for clinical trials investigating the prevention of chronic pain. We present general design considerations for prevention trials in populations that are at relatively high risk for developing chronic pain. Specific design considerations included subject identification, timing and duration of treatment, outcomes, timing of assessment, and adjusting for risk factors in the analyses. We provide a detailed examination of 4 models of chronic pain prevention (ie, chronic postsurgical pain, postherpetic neuralgia, chronic low back pain, and painful chemotherapy-induced peripheral neuropathy). The issues discussed can, in many instances, be extrapolated to other chronic pain conditions. These examples were selected because they are representative models of primary and secondary prevention, reflect persistent pain resulting from multiple insults (ie, surgery, viral infection, injury, and toxic or noxious element exposure), and are chronically painful conditions that are treated with a range of interventions. Improvements in the design of chronic pain prevention trials could improve assay sensitivity and thus accelerate the identification of efficacious interventions. Such interventions would have the potential to reduce the prevalence of chronic pain in the population. Additionally, standardization of outcomes in prevention clinical trials will facilitate meta-analyses and systematic reviews and improve detection of preventive strategies emerging from clinical trials.

National Cancer Institute-supported chemotherapy-induced peripheral neuropathy trials: outcomes and lessons

Chemotherapy-induced peripheral neuropathy (CIPN) is one of the most common and debilitating complications of cancer treatment. Due to a lack of effective management options for patients with CIPN, the National Cancer Institute (NCI) sponsored a series of trials aimed at both prevention and treatment. A total of 15 such studies were approved, evaluating use of various neuro-modulatory agents which have shown benefit in other neuropathic pain states. Aside from duloxetine, none of the pharmacologic methods demonstrated therapeutic benefit for patients with CIPN. Despite these disappointing results, the series of trials revealed important lessons that have informed subsequent work. Some examples of this include the use of patient-reported symptom metrics, the elimination of traditional--yet unsubstantiated--practice approaches, and the discovery of molecular genetic predictors of neuropathy. Current inquiry is being guided by the results from these large-scale trials, and as such, stands better chance of identifying durable solutions for this treatment-limiting toxicity.

Chemotherapy-induced peripheral neurotoxicity and complementary and alternative medicines: progress and perspective

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a severe and dose-limiting side effect of antineoplastic drugs. It can cause sensory, motor and autonomic system dysfunction, and ultimately force patients to discontinue chemotherapy. Until now, little is understood about CIPN and no consistent caring standard is available. Since CIPN is a multifactorial disease, the clinical efficacy of single pharmacological drugs is disappointing, prompting patients to seek alternative treatment options. Complementary and alternative medicines (CAMs), especially herbal medicines, are well known for their multifaceted implications and widely used in human health care. Up to date, several phytochemicals, plant extractions, and herbal formulas have been evaluated for their potential therapeutic benefit of preventing the onset and progression of CIPN in experimental models. Clinical acupuncture has also been shown to improve CIPN symptoms. In this review, we will give an outline of our current knowledge regrading the advanced research of CIPN, the role of CAMs in alleviating CIPN and possible lacunae in research that needs to be addressed.