Predictors of duloxetine response in patients with oxaliplatin-induced painful chemotherapy-induced peripheral neuropathy (CIPN): a secondary analysis of randomised controlled trial - CALGB/alliance 170601

A retrospective cohort study describing chemotherapy-induced peripheral neuropathy in Non-Hodgkin lymphoma patients treated with EPOCH ± R: does HIV status matter?

The frontline immuno-chemotherapy regimen for HIV-associated non-Hodgkin Lymphoma is dose-adjusted EPOCH ± R (etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab). Chemotherapy-induced peripheral neuropathy (CIPN), caused by vincristine, is a common adverse effect of EPOCH ± R, negatively impacting long-term patient outcomes. The primary objective of this study was to determine the incidence of CIPN, stratified by HIV status, in patients treated with EPOCH ± R. A retrospective cohort study at a tertiary referral comprehensive cancer center evaluated patients treated with EPOCH ± R from 2011 to 2018. The final sample included 27 patients with HIV compared to 279 without HIV (total n = 306). Overall, the incidence of CIPN was 29.4% (n = 90), including 5 with HIV (18.5%) and 85 without HIV (30.5%). Propensity scores were used to match patients by HIV status. Although no relationship was found between HIV status and neuropathy, CIPN affects too many undergoing treatments for lymphoma, supporting future investigations to minimize toxicities.

Chemotherapy-Induced Peripheral Neuropathy (CIPN): A Narrative Review and Proposed Theoretical Model

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a common and debilitating symptom experienced by cancer survivors. Despite the burden of CIPN-related symptoms, interventions remain limited.

OBJECTIVES

This narrative review seeks to propose a framework for CIPN predisposing, precipitating, and perpetuating factors (3Ps), which will provide a foundation for future research and clinical interventions aimed at mitigating CIPN-related symptoms and morbidity.

METHODS

A comprehensive literature search was performed using PubMed, guided by keywords related to "chemotherapy-induced peripheral neuropathy." Studies were limited to those with full text available in English.

RESULTS

Predisposing factors outlined in this framework, such as older age and comorbid conditions, can be used to identify patients who have a higher risk of developing CIPN. The major precipitating factor of CIPN is the delivery of chemotherapy to peripheral nerves, which may be mitigated via cryotherapy or compression therapy during chemotherapy. Perpetuating factors can offer insight into psychological, cognitive, and behavioral modifications that could be treatment targets for CIPN management.

CONCLUSION

The proposed 3P model can guide the development of effective interventions for CIPN by suggesting modifiable psychological and behavioral treatment targets that may mitigate the impact of CIPN for cancer patients.

Cryotherapy for prevention of chemotherapy induced peripheral neuropathy in breast cancer

Peripheral neuropathy is a well-described complication of chemotherapy. There are no known treatments to reverse peripheral neuropathy. Chemotherapy-induced peripheral neuropathy is a dose-limiting toxicity in cancer treatment and is debilitating. Cryotherapy, or the use of cold garments/ice bags applied to extremities during chemotherapy, is a method to prevent or minimize treatment related neuropathy. There is no standard method of providing cryotherapy currently. A review of the literature was performed revealing that a variety of cryotherapy methods exist. While small studies suggest potential preventive effect of some forms of cryotherapy, consistent results from well-designed randomized studies are lacking. A small benefit from the use of cryotherapy to prevent peripheral neuropathy might exist, but conflicting studies exist. In light of the low cost to implement ice bags during chemotherapy and the low risk of toxicity, the use of ice bags may be reasonable during taxane chemotherapy for the treatment of breast cancer.

Maximizing treatment efficacy through patient stratification in neuropathic pain trials

Treatment of neuropathic pain remains inadequate despite the elucidation of multiple pathophysiological mechanisms and the development of promising therapeutic compounds. The lack of success in translating knowledge into clinical practice has discouraged pharmaceutical companies from investing in pain medicine; however, new patient stratification approaches could help bridge the translation gap and develop individualized therapeutic approaches. As we highlight in this article, subgrouping of patients according to sensory profiles and other baseline characteristics could aid the prediction of treatment success. Furthermore, novel outcome measures have been developed for patients with neuropathic pain. The extent to which sensory profiles and outcome measures can be employed in routine clinical practice and clinical trials and across distinct neuropathic pain aetiologies is yet to be determined. Improvements in animal models, drawing on our knowledge of human pain, and robust public-private partnerships will be needed to pave the way to innovative and effective pain medicine in the future.

Quantitative proteomic analysis of oxaliplatin induced peripheral neurotoxicity

Oxaliplatin (OXA)-induced peripheral neurotoxicity (OIPN) is a high-incidence and dose-dependent adverse reaction during OXA treatment. Its underlying mechanisms remain unclear, and no effective treatment or prevention therapies are currently available. Here, we employed a data independent acquisition (DIA)-based quantitative proteomic strategy to investigate the global proteome alterations in the dorsal root ganglion (DRG) tissues from mice injected with OXA for different periods. We identified 1128 differentially regulated proteins that were divided into six subclusters according to their alteration trends. Interestingly, these proteins were involved in cellular processes such as cell cycle, ribosomal stress, metabolism, and ion transport. In addition, OXA administration induced abundance changes of ion channels and proteins associated with mitochondrial function and reactive oxygen species production. Furthermore, we investigated the effects of diroximel fumarate (DRF), an FDA-approved oral fumarate drug for the treatment of relapsing forms of multiple sclerosis. Our findings showed that DRF could effectively ameliorate symptoms of OIPN and reduce the level of oxidative stress in mice. Taken together, our study systematically mapped the proteome alteration associated with the neural toxicity of OXA, and the findings could be leveraged to better understand the mechanisms of OIPN and to develop more effect treatment therapies. SIGNIFICANCE: Oxaliplatin (OXA)-induced peripheral neurotoxicity (OIPN) is a high-incidence and dose-dependent adverse reaction with unclear mechanism. Here we employed a data independent acquisition (DIA)-based quantitative proteomic strategy to explore the proteome changes in dorsal root ganglion (DRG) tissues from mice treated by OXA. The findings provided novel insights regarding the mechanisms of OIPN. For example, our data showed that OXA induced a broad disturbance in metabolism, particularly in glycolysis and amino acid metabolism. Additionally, we observed abundance changes of many ion channels and proteins associated with mitochondrial function and reactive oxygen species production. Furthermore, this study provided the first evidence for the possibility of repositioning diroximel fumarate (DRF) for treating OIPN.

Application Potential of Plant-Derived Medicines in Prevention and Treatment of Platinum-Induced Peripheral Neurotoxicity

As observed with other chemotherapeutic agents, the clinical application of platinum agents is a double-edged sword. Platinum-induced peripheral neuropathy (PIPN) is a common adverse event that negatively affects clinical outcomes and patients’ quality of life. Considering the unavailability of effective established agents for preventing or treating PIPN and the increasing population of cancer survivors, the identification and development of novel, effective interventions are the need of the hour. Plant-derived medicines, recognized as ideal agents, can not only help improve PIPN without affecting chemotherapy efficacy, but may also produce synergy. In this review, we present a brief summary of the mechanisms of platinum agents and PIPN and then focus on exploring the preventive or curative effects and underlying mechanisms of plant-derived medicines, which have been evaluated under platinum-induced neurotoxicity conditions. We identified 11 plant extracts as well as 17 plant secondary metabolites, and four polyherbal preparations. Their effects against PIPN are focused on oxidative stress and mitochondrial dysfunction, glial activation and inflammation response, and ion channel dysfunction. Also, ten clinical trials have assessed the effect of herbal products in patients with PIPN. The understanding of the molecular mechanism is still limited, the quality of clinical trials need to be further improved, and in terms of their efficacy, safety, and cost effectiveness studies have not provided sufficient evidence to establish a standard practice. But plant-derived medicines have been found to be invaluable sources for the development of natural agents with beneficial effects in the prevention and treatment of PIPN.

Updates in the Treatment of Chemotherapy-Induced Peripheral Neuropathy

OPINION STATEMENT

Chemotherapy-induced peripheral neuropathy (CIPN) is a common toxicity associated with treatment with platinum-based agents, taxanes, vinca alkaloids, and other specific agents. The long-term consequences of this condition can result in decreased patient quality of life and can lead to reduced dose intensity, which can negatively impact disease outcomes. There are currently no evidence-based preventative strategies for CIPN and only limited options for treatment. However, there are several strategies that can be utilized to improve patient experience and outcomes as more data are gathered in the prevention and treatment setting. Before treatment, patient education on the potential side effects of chemotherapy is key, and although trials have been limited, recommending exercise and a healthy lifestyle before and while undergoing chemotherapy may provide some overall benefit. In patients who develop painful CIPN, our approach is to offer duloxetine and titrate up to 60 mg daily. Chemotherapy doses may also need to be reduced if intolerable symptoms develop during treatment. Some patients may also try acupuncture and physical therapy to help address their symptoms, although this can be limited by cost, time commitment, and patient motivation. Additionally, data on these modalities are currently limited, as studies are ongoing. Overall, approaching each patient on an individual level and tailoring treatment options for them based on overall physical condition, their disease burden, goals of care and co-morbid health conditions, and willingness to trial different approaches is necessary when addressing CIPN.

Target enzymes in oxaliplatin-induced peripheral neuropathy in Swiss mice: A new acetylcholinesterase inhibitor as therapeutic strategy

In the present study it was hypothesized that 5-((4-methoxyphenyl)thio)benzo[c][1,2,5] thiodiazole (MTDZ), a new acetylcholinesterase inhibitor, exerts antinociceptive action and reduces the oxaliplatin (OXA)-induced peripheral neuropathy and its comorbidities (anxiety and cognitive deficits). Indeed, the acute antinociceptive activity of MTDZ (1 and 10 mg/kg; per oral route) was observed for the first time in male Swiss mice in formalin and hot plate tests and on mechanical withdrawal threshold induced by Complete Freund's Adjuvant (CFA). To evaluate the MTDZ effect on OXA-induced peripheral neuropathy and its comorbidities, male and female Swiss mice received OXA (10 mg/kg) or vehicle intraperitoneally, on days 0 and 2 of the experimental protocol. Oral administration of MTDZ (1 mg/kg) or vehicle was performed on days 2-14. OXA caused cognitive impairment, anxious-like behaviour, mechanical and thermal hypersensitivity in animals, with females more susceptible to thermal sensitivity. MTDZ reversed the hypersensitivity, cognitive impairment and anxious-like behaviour induced by OXA. Here, the negative correlation between the paw withdrawal threshold caused by OXA and acetylcholinesterase (AChE) activity was demonstrated in the cortex, hippocampus, and spinal cord. OXA inhibited the activity of total ATPase, Na⁺ K⁺ - ATPase, Ca²⁺ - ATPase and altered Mg²⁺ - ATPase in the cortex, hippocampus, and spinal cord. OXA exposure increased reactive species (RS) levels and superoxide dismutase (SOD) activity in the cortex, hippocampus, and spinal cord. MTDZ modulated ion pumps and reduced the oxidative stress induced by OXA. In conclusion, MTDZ is an antinociceptive molecule promising to treat OXA-induced neurotoxicity since it reduced nociceptive and anxious-like behaviours, and cognitive deficit in male and female mice.

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.

Colorectal Cancer Survivors Suffering From Sensory Chemotherapy-Induced Peripheral Neuropathy Are Not a Homogenous Group: Secondary Analysis of Patients' Profiles With Oxaliplatin-Induced Peripheral Neuropathy

Oxaliplatin, a pivotal drug in the management of colorectal cancer, causes chemotherapy-induced peripheral neuropathy (CIPN) in a third of cancer survivors. Based on a previous cross-sectional study assessing oxaliplatin-related sensory CIPN in colorectal cancer survivors, a secondary analysis was designed to explore the possibility that different clusters of patients may co-exist among a cohort of patients with oxaliplatin-related CIPN. Other objectives were to characterize these clusters considering CIPN severity, anxiety, depression, health-related quality of life (HRQOL), patients’ characteristics and oxaliplatin treatments. Among the 96 patients analyzed, three clusters were identified (cluster 1: 52, cluster 2: 34, and cluster 3: 10 patients). Clusters were significantly different according to CIPN severity and the proportion of neuropathic pain (cluster 1: low, cluster 2: intermediate, and cluster 3: high). Anxiety, depressive disorders and HRQOL alteration were lower in cluster 1 in comparison to clusters 2 and 3, but not different between clusters 2 and 3. This study underlines that patients with CIPN are not a homogenous group, and that CIPN severity is associated with psychological distress and a decline of HRQOL. Further studies are needed to explore the relation between clusters and CIPN management.

Monosialotetrahexosylganglioside in the treatment of chronic oxaliplatin-induced peripheral neurotoxicity: TJMUCH-GI-001, a randomised controlled trial

BACKGROUND

Chronic oxaliplatin-induced peripheral neurotoxicity (OIPN) is the most troublesome and dose-limiting side effect of oxaliplatin. There is no effective treatment for chronic OIPN. We conducted a randomised controlled trial to investigate the efficacy of monosialotetrahexosylganglioside (GM1) in treating chronic OIPN.

METHODS

In this single-centre, double-blind, phase Ⅲ trial, gastrointestinal cancer patients with persistent chronic OIPN were randomised in 1:1 ratio to receive either GM1 or placebo at Tianjin Medical University Cancer Institute and Hospital, China. GM1 was dosed at 60 mg daily for every 3 weeks or 40 mg daily for every 2 weeks. Seven- and fourteen- day infusions were administered to concurrent oxaliplatin users and oxaliplatin discontinuation patients, respectively. The primary endpoint was the relief of neurotoxicity (≥30% improvement), measured by a newly developed patient reported outcome measure (MCIPN) based on prior questionnaires including the European Organization for Research and Treatment of Cancer Quality of Life Chemotherapy Induced Peripheral Neuropathy Questionnaire twenty-item scale. Visual analogue score (VAS) was used as another instrument for patients to evaluate the total Chronic OIPN treatment effect. VAS responders (≥30% improvement), double responders (≥30% improvement in both MCIPN and VAS), and high responders (≥50% improvement in the MCIPN total score) were also calculated. The secondary endpoints were safety and quality of life. The additional endpoints are progression-free survival (PFS), disease-free survival (DFS), overall survival (OS), and tumour response. (Trial registration number: NCT02486198 at ClinicalTrials.gov).

FINDINGS

Between May 2015 to December 2017, 145 patients were randomly assigned to receive either GM1 (n=73) and placebo (n=72). Majority of the patients in both arms (90% in GM1 and 83% in placebo) continued receiving oxaliplatin on the trial. More patients responded in the GM1 group than in the placebo group (MCIPN responders: 53% vs 14%, VAS responders: 49% vs 22%, double responders: 41% vs 7%, and high responders: 32% vs 13%, all P < ·01). Analyses were also performed in concurrent oxaliplatin users. The results were consistent with those of the whole group. No deleterious effects of GM1 on survival or tumour response were found. There were no ≥G3 GM1-related adverse events.

INTERPRETATION

In patients with chronic OIPN, the use of GM1 reduces the severity of chronic OIPN compared with placebo.

FUNDING

This work was supported by clinical trial development fund of Tianjin Medical University Cancer Institute and Hospital (No.C1706).

Targeting strategies for oxaliplatin-induced peripheral neuropathy: clinical syndrome, molecular basis, and drug development

Oxaliplatin (OHP)-induced peripheral neurotoxicity (OIPN) is a severe clinical problem and potentially permanent side effect of cancer treatment. For the management of OIPN, accurate diagnosis and understanding of significant risk factors including genetic vulnerability are essential to improve knowledge regarding the prevalence and incidence of OIPN as well as enhance strategies for the prevention and treatment of OIPN. The molecular mechanisms underlying OIPN are complex, with multi-targets and various cells causing neuropathy. Furthermore, mechanisms of OIPN can reinforce each other, and combination therapies may be required for effective management. However, despite intense investigation in preclinical and clinical studies, no preventive therapies have shown significant clinical efficacy, and the established treatment for painful OIPN is limited. Duloxetine is the only agent currently recommended by the American Society of Clinical Oncology. The present article summarizes the most recent advances in the field of studies on OIPN, the overview of the clinical syndrome, molecular basis, therapy development, and outlook of future drug candidates. Importantly, closer links between clinical pain management teams and oncology will advance the effectiveness of OIPN treatment, and the continued close collaboration between preclinical and clinical research will facilitate the development of novel prevention and treatments for OIPN.

Efficacy of the Motivational Interviewing-Walk Intervention for Chemotherapy-Induced Peripheral Neuropathy and Quality of Life During Oxaliplatin Treatment: A Pilot Randomized Controlled Trial

BACKGROUND

Oxaliplatin-induced peripheral neuropathy (OIPN) is prevalent among gastrointestinal cancer survivors and often impairs quality of life (QOL).

OBJECTIVE

This pilot randomized controlled trial aimed to explore the effect of an 8-week home-based brisk walking (the "MI-Walk") intervention on (1) OIPN severity and (2) QOL at 8 weeks, compared with physical activity (PA) education alone in oxaliplatin-receiving adults with gastrointestinal cancer.

INTERVENTIONS/METHODS

Participants (N = 57) recruited from 5 infusion sites received PA education at their second oxaliplatin visit, followed by phone assessments of adverse events over 8 weeks. Half (n = 29) received additional MI-Walk intervention motivational supports (eg, a Fitbit Charge 2 and motivational enhancement therapy sessions). Self-reported OIPN, QOL, and PA were measured before and after intervention.

RESULTS

The intervention compared with the control condition had no effect on sensory OIPN (mean difference [X¯[INCREMENT]] = -0.01; P > .99), motor OIPN (X¯[INCREMENT] = 2.39; P = .17), and QOL (X¯[INCREMENT] = -1.43; P > .99). Eight-week sensory (X¯ =11.48 ± 0.38) and motor OIPN severities (X¯ = 7.48 ± 0.36) were mild but higher than baseline (P ≤ .01). Self-reported PA level increased over time in both groups (X¯[INCREMENT] = 44.85; P = .01). Averaging ≥225 moderate to vigorous PA minutes per week led to less sensory OIPN, particularly finger/hand tingling (X¯[INCREMENT] = -26.35; P = .01).

CONCLUSIONS

This study failed to detect beneficial effects of the MI-Walk intervention; however, the findings suggest that aerobic walking may blunt but not completely prevent OIPN. Further research is necessary.

IMPLICATIONS FOR PRACTICE

Although the effectiveness of brisk walking in reducing OIPN is unclear, this study supports prior evidence that moderate to vigorous PA is beneficial and safe during chemotherapy treatment.

Post-mastectomy pain syndrome: A timely review of its predisposing factors and current approaches to treatment

Background:

Post-mastectomy pain syndrome (PMPS) has been reported to occur in 25–60% of patients following surgeries for breast cancer, the highest occurring cancer in women worldwide. There has been much research interest due to this high prevalence. However, there is still a lack of incorporation of PMPS prevention strategies in standard perioperative plans, and our understanding of this condition is still incomplete.

Objectives:

This narrative review discusses recent literature on modifiable risk factors, current approaches to prevention and treatment and potential directions for future treatment and research.

Methods:

A PubMed search with the relevant keywords was done for articles published in the last 10 years.

Results:

The incidence of PMPS can be reduced by early recognition and management of modifiable risk factors as well as the perioperative use of analgesics and regional nerve blocks. These also have a significant role in the management of established PMPS together with surgical interventions and physical therapy.

Conclusions:

PMPS is still poorly defined and hence underdiagnosed and undertreated at this point. Perioperative peripheral nerve blocks have a very promising role as preventive analgesia to reduce the risk of developing PMPS, but large-scale randomised controlled studies will need to be done to evaluate their comparative efficacy. There is a need to prioritise PMPS prevention as a standard inclusion into the perioperative plans of mastectomy patients.

Duloxetine against symptomatic chemotherapy-induced peripheral neurotoxicity in cancer survivors: a real world, open-label experience

The objective of this observational study was to evaluate the efficacy and safety of duloxetine in a cohort of 100 cancer survivors with chemotherapy-induced peripheral neurotoxicity (CIPN). CIPN was graded employing the TNSc and the NCI-CTCv4. The Patient Global Impression of Change (PGIC) scale measured the efficacy of duloxetine (1: no benefit; to 7: excellent response). A clinically meaningful response was considered a PGIC > 4. Median age was 62 (29-81) years and 42% were male. CIPN was graded as grades 1, 2 and 3 in 20, 66, and 14% of patients, respectively. Median time to duloxetine initiation was 6 (1-63) months after chemotherapy. Fifty-seven patients early dropped out from duloxetine, due to lack of efficacy (20%) or side effects (37%). Male patients more frequently discontinued duloxetine due to lack of efficacy (35.7 vs. 8.6% P = 0.001). PGIC scores were higher in female patients (4 vs. 1, P = 0.001), taxane-treated patients (4 vs. 1, P = 0.042) and with short-lasting (<6 months) CIPN (4 vs. 1, P = 0.008). Patients with long-lasting CIPN had a higher rate of adverse events (47 vs. 27%, P = 0.038) and discontinuation (54.8 vs. 45.1%, P = 0.023). In the multivariate analysis, female gender and short-lasting CIPN were independently associated with a favorable response to duloxetine. Low tolerability, male gender, and long-lasting CIPN significantly limited duloxetine use in daily practice setting. A minority of cancer survivors with CIPN treated with duloxetine had a meaningful CIPN improvement, and tolerability was overall low. Female gender and short-term CIPN were independently associated with a favorable response to duloxetine.

Oral pharmacotherapeutics for the management of peripheral neuropathic pain conditions - a review of clinical trials

INTRODUCTION

Epidemiological studies have shown that 6.9-10% of people suffer from neuropathic pain, a complex painful condition which is often undertreated. Data regarding the effectiveness of treatment options for patients with neuropathic pain is inconsistent, and there is no single treatment option that shows cost-effectiveness across studies.

AREAS COVERED

In this narrative review, the authors present the results of different prospective, randomized controlled trials, systematic reviews and meta-analyses assessing the effects of different oral medications in the management of various peripheral neuropathic pain conditions. The authors discuss the effectiveness of commonly used oral medications such as voltage-gated calcium channels antagonists, voltage-gated sodium channel antagonists, serotonin-norepinephrine reuptake inhibitors, NMDA antagonists, and medications with other mechanisms of action.

EXPERT OPINION

Most of the presented medications were more effective than placebo; however, when compared to each other, none of them were significantly superior. The heterogeneity of the studies looking into different oral neuropathic conditions has been the major issue that prevents us from making stronger recommendations. There are multiple reasons including high placebo responsiveness, improperly treated underlying comorbidities (particularly anxiety and depression), and inter-patient variability. Different sensory phenotypes should also be taken into consideration when designing future clinical trials for neuropathic pain.

Comparison of clinical characteristics of post-refractive surgery-related and post-herpetic neuropathic corneal pain

Purpose:

To compare the clinical characteristics and in vivo confocal microscopy (IVCM) findings of patients with neuropathic corneal pain (NCP) due to refractive surgery (RS-NCP) and herpetic eye disease (H-NCP) to controls.

Methods:

Sixteen patients with RS-NCP and 7 patients with H-NCP, and 37 healthy reference age- and sex-matched healthy controls were included to the study. The medical records were reviewed for demographic features, detailed disease history, ocular surface disease index (OSDI), ocular pain assessment survey (OPAS) scores. IVCM images of patients were analyzed and compared to reference controls by two masked observers.

Results:

The mean pain intensity score for the last 24 h (5.1 ± 2.4 vs. 3.9 ± 1.2; p = 0.27), last 2 weeks (6.1 ± 2.5 vs. 4.8 ± 2.3; p = 0.13) for RS-NCP vs. H-NCP respectively, and quality of life scores (p = 0.23) were similar in both groups. Quality of life, especially mood (p = 0.06) and enjoying life/relations to others (p = 0.10) were affected in both groups, but were not statistically significant between groups. The mean total nerve density was lower in RS-NCP (5,702.4 ± 4,599.0 μm/mm²) compared to their respective controls (26,422.8 ± 4,491.0; p < 0.001) and in the H-NCP group (2,149.5 ± 2,985.9) compared to their respective controls (22,948.8 ± 3,169.0; p < 0.001). Alterations in DC density were similar between all groups (38.3 ± 48.0 cells/mm² in RS-NCP, 61.0 ± 76.9 in H-NCP, p = 0.95).

Conclusion:

Neuropathic corneal pain patients due to refractive surgery show similar clinical characteristics, pain levels, quality of life impact, and IVCM findings as patients with NCP due to herpetic eye disease.

Understanding voluntariness of consent in first-in-human cell therapy trials

Consensus about contents of voluntariness in informed consent is lacking. Core criteria for voluntary consent are needed to ensure voluntariness. This article outlines the multidimensionality of voluntariness and identifies what could reduce voluntariness, especially in first-in-human clinical trials involving cell therapies. In such trials, truly voluntary consent is especially important because: such trials may involve risk of serious harm, while in case of some diseases, eligible patients often have potentially effective therapeutic alternatives; patients considering participation in high-risk first-in-human trials may feel more desperate and some may be dependent on their caregivers, including those in the family; implanted cells cannot be taken out of the patient's body if the patient wants to withdraw.

Oxaliplatin-Induced Lhermitte's Sign in Gastric Cancer

A 64-year-old Japanese man with no significant medical history presented with epigastric discomfort of 2-weeks' duration. He was diagnosed with metastatic HER2-positive gastric cancer. Chemotherapy with capecitabine, oxaliplatin, and trastuzumab was initiated. During the eighth cycle, he suddenly complained of electric shock-like pain in both legs upon neck flexion, consistent with Lhermitte's sign. Oxaliplatin was discontinued, and Lhermitte's sign resolved after 3 months. Neurotoxicity is commonly observed in platinum-based chemotherapy, but Lhermitte's sign is rare. This is the first report of oxaliplatin-induced Lhermitte's sign in a gastric cancer patient.

Management of Oxaliplatin-Induced Peripheral Sensory Neuropathy

Oxaliplatin-induced peripheral neurotoxicity (OIPN) is a severe and potentially permanent side effect of cancer treatment affecting the majority of oxaliplatin-treated patients, mostly with the onset of acute symptoms, but also with the establishment of a chronic sensory loss that is supposed to be due to dorsal root ganglia neuron damage. The pathogenesis of acute as well as chronic OIPN is still not completely known, and this is a limitation in the identification of effective strategies to prevent or limit their occurrence. Despite intense investigation at the preclinical and clinical levels, no treatment can be suggested for the prevention of OIPN, and only limited evidence for the efficacy of duloxetine in the treatment setting has been provided. In this review, ongoing neuroprotection clinical trials in oxaliplatin-treated patients will be analyzed with particular attention paid to the hypothesis leading to the study, to the trial strengths and weaknesses, and to the outcome measures proposed to test the efficacy of the therapeutic approach. It can be concluded that (1) prevention and treatment of OIPN still remains an important and unmet clinical need, (2) further, high-quality research is mandatory in order to achieve reliable and effective results, and (3) dose and schedule modification of OHP-based chemotherapy is currently the most effective approach to limit the severity of OIPN.

Chemotherapy-induced peripheral neuropathy-part 2: focus on the prevention of oxaliplatin-induced neurotoxicity

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is regarded as one of the most common dose-limiting adverse effects of several chemotherapeutic agents, such as platinum derivatives (oxaliplatin and cisplatin), taxanes, vinca alkaloids and bortezomib. CIPN affects more than 60% of patients receiving anticancer therapy and although it is a nonfatal condition, it significantly worsens patients' quality of life. The number of analgesic drugs used to relieve pain symptoms in CIPN is very limited and their efficacy in CIPN is significantly lower than that observed in other neuropathic pain types. Importantly, there are currently no recommended options for effective prevention of CIPN, and strong evidence for the utility and clinical efficacy of some previously tested preventive therapies is still limited.

METHODS

The present article is the second one in the two-part series of review articles focused on CIPN. It summarizes the most recent advances in the field of studies on CIPN caused by oxaliplatin, the third-generation platinum-based antitumor drug used to treat colorectal cancer. Pharmacological properties of oxaliplatin, genetic, molecular and clinical features of oxaliplatin-induced neuropathy are discussed.

RESULTS

Available therapies, as well as results from clinical trials assessing drug candidates for the prevention of oxaliplatin-induced neuropathy are summarized.

CONCLUSION

Emerging novel chemical structures-potential future preventative pharmacotherapies for CIPN caused by oxaliplatin are reported.

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.

Quality of Life in Painful Peripheral Neuropathies: A Systematic Review

Objective

Neuropathic pain is a common presenting complaint of patients with peripheral neuropathy (PN) and is considered one of the most disabling neuropathic symptoms, with detrimental effects on patients' quality of life (QoL). The aim of this review was to overview the current literature that focuses on QoL in painful PN of various aetiologies. We sought to clarify the direct effect of pain and its treatment on patients' QoL.

Methodology

A systematic computer-based literature search was conducted using the PubMed database to search for papers on QoL in painful PN. Information was extracted regarding prevalence, demographics, and response to treatment where relevant.

Results

We identified 66 articles eligible for inclusion. The vast majority of studies (n=47) focused on patients with diabetic PN. Other aetiologies of painful PN where QoL has been studied to date include gluten, immune-mediated, HIV, chemotherapy-induced, and chronic idiopathic axonal polyneuropathy. Pharmacological treatment is the mainstay in managing pain and has a direct positive and independent effect on the overall QoL. Other nonpharmacological approaches can also be of benefit, either alone or as adjuvant treatments, and are discussed.

Conclusion

The findings demonstrate that QoL is impaired in painful PN and should not be neglected in clinical practice. Patients' pain management and subsequent impact on QoL should routinely be assessed and monitored.

Mechanisms, Predictors, and Challenges in Assessing and Managing Painful Chemotherapy-Induced Peripheral Neuropathy

OBJECTIVE

To describe the known predictors and pathophysiological mechanisms of chronic painful chemotherapy-induced peripheral neuropathy (CIPN) in cancer survivors and the challenges in assessing and managing it.

DATA SOURCES

PubMed/Medline, CINAHL, Scopus, and PsycINFO.

CONCLUSION

The research on chronic painful CIPN is limited. Additional research is needed to identify the predictors and pathophysiological mechanisms of chronic painful CIPN to inform the development of assessment tools and management options for this painful and possibly debilitating condition.

IMPLICATIONS FOR NURSING PRACTICE

Recognition of the predictors of chronic painful CIPN and proactive CIPN assessment and palliative management are important steps in reducing its impact on physical function and quality of life.

Duloxetine, a Balanced Serotonin-Norepinephrine Reuptake Inhibitor, Improves Painful Chemotherapy-Induced Peripheral Neuropathy by Inhibiting Activation of p38 MAPK and NF-κB

Chemotherapy-induced peripheral neuropathy (CIPN) is a severe, toxic side effect that frequently occurs in anticancer treatment and may result in discontinuation of treatment as well as a serious reduction in life quality. The CIPN incidence rate is as high as 85–90%. Unfortunately, there is currently no standard evidence-based CIPN treatment. In several clinical trials, it has been reported that duloxetine can improve CIPN pain induced by oxaliplatin (OXA) and paclitaxel (PTX); thus, The American Society of Clinical Oncology (ASCO) recommends duloxetine as the only potential treatment for CIPN. However, this guidance lacks the support of sufficient evidence. Our study shows that duloxetine markedly reduces neuropathic pain evoked by OXA or PTX. Duloxetine acts by inhibiting the activation of p38 phosphorylation, thus preventing the activation and nuclear translocation of the NF-κB transcription factor, reducing the inflammatory response and inhibiting nerve injury by regulating nerve growth factor (NGF). Furthermore, in this study, it is shown that duloxetine does not affect the antitumor activity of OXA or PTX. This study not only provides biological evidence to support the use of duloxetine as the first standard CIPN drug but will also lead to potential new targets for CIPN drug development.

Estimating the Frequency, Severity, and Clustering of SPADE Symptoms in Chronic Painful Chemotherapy-Induced Peripheral Neuropathy

BACKGROUND

Patients undergoing treatment for cancer commonly experience symptoms such as sleep disturbance, pain, anxiety, depression, and low energy/fatigue (SPADE), subsequently altering physical function and complicating effective symptom management. However, little is known about the frequency, severity, and clustering of SPADE symptoms in individuals with chronic painful chemotherapy-induced peripheral neuropathy (CIPN). Aims/Design: The purpose of this cross-sectional, secondary analysis was to describe the frequency, severity, and clustering of SPADE symptoms and their association with physical function in individuals with chronic painful CIPN. Participants/Subjects: Sixty individuals with chronic painful CIPN were recruited from five academic and community oncology outpatient center to participate in a randomized controlled pilot trial designed to test the efficacy of a cognitive behavioral therapy-based pain management program.

METHODS

Participants completed the 0-10 Average CIPN Pain Numerical Rating Scale and Patient-Reported Outcome Measurement Information System measures for sleep-related impairment, anxiety, depression, fatigue, and pain interference via tablet before being randomly assigned to a study arm. The frequency, severity, and clustering of SPADE symptoms were calculated via descriptive statistics and Partitioning Around Medoids cluster analysis. Spearman rank correlation was performed to determine the association between number of SPADE symptoms and pain interference severity.

RESULTS AND CONCLUSIONS

Participants (n = 59) experienced numerous SPADE symptoms. 66.1% of participants experienced at least two SPADE symptoms concurrently. The cluster analysis revealed high (n = 36) and low (n = 23) severity subgroups. There was a moderate correlation (r = 0.48) between the number of SPADE symptoms and pain interference severity. Determining the clustering of SPADE symptoms in individuals with chronic painful CIPN may lead to targeted multifaceted interventions to improve physical function.

Médiateurs potentiels d’amélioration de la neuropathie périphérique chimio-induite douloureuse par une intervention cognitivocomportementale en ligne

Objet

Des données préliminaires ont révélé qu’une intervention autoguidée cognitivocomportementale de gestion de la douleur (PROSPECT) était efficace contre la neuropathie périphérique chronique douloureuse induite par chimiothérapie (NPCI), mais le mécanisme d’action demeure inconnu. L’objectif de cette analyse secondaire a consisté à déterminer si les changements par rapport à l’anxiété, à la dépression, aux troubles du sommeil ou à la fatigue diminuaient la douleur après l’utilisation de PROSPECT chez les patients atteints de NPCI.

Méthodologie

En tout, 60 participants ont été sélectionnés au hasard pour recevoir soit l’intervention autoguidée cognitivocomportementale contre la douleur (accès pendant huit semaines), soit le traitement habituel. Un journal sur sept jours de suivi de la douleur due à la NPCI et le système PROMIS (Patient Reported Outcomes Measurement Information System) de mesure de l’anxiété, de la dépression, de la fatigue et des troubles du sommeil ont été utilisés avant et après l’étude (huit semaines). L’analyse de la médiation causale a été utilisée pour quantifier les médiateurs d’amélioration quant aux douleurs les plus intenses.

Résultats

Aucun des médiateurs hypothétiques n’a eu un effet statistiquement important sur les douleurs les plus fortes (n = 38).

Implications

D’autres recherches sont nécessaires pour déterminer les médiateurs potentiels d’intensité de la douleur qui peuvent être ciblés par des stratégies cognitivocomportementales spécifiques afin d’améliorer la gravité de la douleur de la CIPN.

Potential mediators of improvement in painful chemotherapy-induced peripheral neuropathy via a web-based cognitive behavioural intervention

PURPOSE

Preliminary evidence suggests that a self-guided cognitive and behaviourally-based pain management intervention (PROSPECT) is effective for chronic painful chemotherapy-induced peripheral neuropathy (CIPN), but its mechanism of action is unknown. The purpose of this secondary analysis was to explore if changes in anxiety, depression, sleep-related impairment, or fatigue mediated improvements in worst pain following PROSPECT in individuals with chronic painful CIPN.

METHODS

Sixty participants were randomized to receive self-guided cognitive behavioural pain management (access for eight weeks) or treatment as usual. A seven-day worst CIPN pain diary and the PROMIS measures of anxiety, depression, fatigue, and sleep-related impairment were administered pre/posttest (eight-weeks). Causal mediation analysis was used to quantify mediators of worst pain improvement.

RESULTS

None of the hypothesized mediators had a statistically significant effect on worst pain (n=38).

IMPLICATIONS

Further research is needed to identify potential mediators of pain intensity that can be targeted by specific cognitive behavioural strategies to improve painful CIPN severity.

Persistent Post-Mastectomy Pain: Risk Factors and Current Approaches to Treatment

Persistent Post-Mastectomy Pain (PPMP) is a common condition that can follow surgeries for breast cancer, the most common cancer in women. Because of the frequency of PPMP and its potential severity, it has received increasing research attention. This manuscript reviews the recent research literature, beginning with a brief history and then relevant medical, surgical, demographic, and psychosocial risk factors. Subsequently, social, psychological, and functional sequelae that have been linked to PPMPS are considered, as is research on current pharmacological, psychological, and rehabilitative approaches to treatment. The review concludes with a discussion of directions for future research and treatment that might reduce the incidence and impact of PPMP on breast cancer survivors. PERSPECTIVE: This article describes current research literature involving mechanisms, risks, and treatments related to persistent post-mastectomy pain. Implications of research findings also are discussed for pre- and post-surgical approaches to pain management, current treatments, and promising research directions.

Chemotherapy-induced peripheral neuropathy: a review of recent findings

PURPOSE OF REVIEW

Chemotherapy-induced peripheral neuropathy (CIPN) is a common, frequently chronic condition characterized by pain and decreased function. Given the growing number of cancer survivors and an increasing recognition of opioid therapy limitations, there is a need for critical analysis of the literature in directing an informed and thoughtful approach for the management of painful CIPN.

RECENT FINDINGS

A PubMed search for 'chemotherapy-induced peripheral neuropathy AND pain' identifies 259 publications between 1 January 2016 and 31 March 2017. Based on review of this literature, we aim to present a clinically relevant update of painful CIPN. Notably, the use of duloxetine as a first-line agent in treatment of CIPN is confirmed. Moreover, clinical trials focus on nonpharmacologic strategies for managing painful CIPN.

SUMMARY

Despite the volume of recent publications, there are limited preventive or therapeutic strategies for CIPN supported by high-level evidence. Duloxetine remains the only pharmacologic agent with demonstrated benefit; its clinical use should be routinely considered. Moving forward, nonopioid analgesic therapies will likely play an increasing role in CIPN treatment, but further research is necessary to confirm their utility. Promising therapies include vitamin B12 supplementation, physical therapy, and various forms of neuromodulation.

A rat model of FOLFOX-induced neuropathy: effects of oral dimiracetam in comparison with duloxetine and pregabalin

BACKGROUND AND AIM

The FOLFOX family of chemotherapy regimens are hampered by the development of a painful neuropathy. Current clinical treatments are inadequate, and furthermore, the research of innovative drugs is strongly disadvantaged by the absence of a preclinical model based on the complete mixture of FOLFOX components. The aim of this study was to set up a rat model of FOLFOX-induced neuropathy in rats, validate its predictability by reference drugs, and evaluate the effectiveness of the new anti-neuropathic compound dimiracetam.

METHODS

Male Sprague-Dawley rats were treated intraperitoneally with the FOLFOX components (6 mg kg^-1 oxaliplatin, 50 mg kg^-1 5-FU, 90 mg kg^-1 leucovorin calcium salt) or oxaliplatin alone (6 mg kg^-1) on days 0, 7, 14, and 21, whereas a separate group received one more injection of FOLFOX on day 28. Pain behavioural measurements (paw pressure, cold plate, and electronic Von Frey tests) and motor coordination (Rota-rod test) were assessed before and after treatments. Behavioural, motor, neurological, and autonomic parameters (open field and Irwin tests) were evaluated.

RESULTS

FOLFOX reduced the pain threshold in response to mechanical noxious and thermal (cold) non-noxious stimuli beginning from day 14 up to day 42 comparably to oxaliplatin alone. A fifth FOLFOX injection enhanced the severity but not the duration of painful alterations. Spontaneous activity, behavioural, autonomic, and neurological functions were also affected, whereas the motor coordination was not altered. On day 22, duloxetine (15 mg kg^-1, per os), morphine (10 mg kg^-1, subcutaneously), or pregabalin (20 mg kg^-1, per os), acutely administered, reduced the FOLFOX-dependent hypersensitivity. Repeated treatments with dimiracetam (150 mg kg^-1, per os, twice daily, from day 22) significantly protected rats from FOLFOX-induced alterations of pain threshold as well as from autonomic and neurological impairments taking effect after 7 days treatment. Pregabalin repeatedly administered (20 mg kg^-1, per os, twice daily, from day 22) was less effective in reducing mechanical hypersensitivity.

CONCLUSION

A clinically consistent model of FOLFOX-induced neurotoxicity has been developed in rats. Dimiracetam fully reduced hypersensitivity and neurological alterations showing a relevant profile as anti-neuropathic resource.