Burden of chemotherapy-induced neuropathy--a cross-sectional study

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.

Impact of exercise on chemotherapy-induced peripheral neuropathy in survivors with post-treatment primary breast cancer

PURPOSE

Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating side effect of neurotoxic chemotherapy. Exercise activates neuromuscular function and may improve CIPN. We examined the association between exercise and CIPN symptoms in breast cancer survivors.

METHODS

In a retrospective cross-sectional study, we included patients completing a survey assessing exercise exposure and neuropathy symptoms in a tertiary cancer center survivorship clinic. We evaluated exercise duration and intensity using a standardized questionnaire quantified in metabolic equivalent tasks (MET-h/wk). We defined exercisers as patients meeting the National Physical Activity Guidelines' criteria. We used multivariable logistic regressions to examine the relationship between exercise and CIPN and if this differed as a function of chemotherapy regimen adjusting for age, gender, and race.

RESULTS

We identified 5444 breast cancer survivors post-chemotherapy (median age 62 years (interquartile range [IQR]: 55, 71); median 4.7 years post-chemotherapy (IQR: 3.3, 7.6)) from 2017 to 2022. CIPN overall prevalence was 34% (95% confidence interval [CI]: 33%, 36%), 33% for non-taxane, and 37% for taxane-based chemotherapy. CIPN prevalence was 28% (95% CI: 26%, 30%) among exercisers and 38% (95% CI: 37%, 40%) among non-exercisers (difference 11%; 95% CI: 8%, 13%; p < 0.001). Compared to patients with low (<6 MET-h/wk) levels of exercise (42%), 11% fewer patients with moderate (6-20.24 MET-h/wk) to high (>20.25 MET-h/wk) levels of exercise reported CIPN. Exercise was associated with reduced prevalence of all CIPN symptoms regardless of chemotherapy type.

CONCLUSION

CIPN may persist several years following chemotherapy among patients with breast cancer but is significantly reduced by exercise in a dose-dependent manner.

Impact of Cannabidiol and Exercise on Clinical Outcomes and Gut Microbiota for Chemotherapy-Induced Peripheral Neuropathy in Cancer Survivors: A Case Report

Chemotherapy-induced peripheral neuropathy (CIPN) remains a clinical challenge for up to 80% of breast cancer survivors. In an open-label study, participants underwent three interventions: standard care (duloxetine) for 1 month (Phase 1), oral cannabidiol (CBD) for 2 months (Phase 2), and CBD plus multi-modal exercise (MME) for another 2 months (Phase 3). Clinical outcomes and gut microbiota composition were assessed at baseline and after each phase. We present the case of a 52-year-old female with a history of triple-negative breast cancer in remission for over five years presenting with CIPN. She showed decreased monocyte counts, c-reactive protein, and systemic inflammatory index after each phase. Duloxetine provided moderate benefits and intolerable side effects (hyperhidrosis). She experienced the best improvement and least side effects with the combined (CBD plus MME) phase. Noteworthy were clinically meaningful improvements in CIPN symptoms, quality of life (QoL), and perceived physical function, as well as improvements in pain, mobility, hand/finger dexterity, and upper and lower body strength. CBD and MME altered gut microbiota, showing enrichment of genera that produce short-chain fatty acids. CBD and MME may improve CIPN symptoms, QoL, and physical function through anti-inflammatory and neuroprotective effects in cancer survivors suffering from long-standing CIPN.

Vincristine-Induced Neuropathy in Patients Diagnosed with Solid and Hematological Malignancies: The Role of Dose Rounding

BACKGROUND

Vincristine is a vital constituent of chemotherapeutic regimens. Vincristine-induced neuropathy is a challenging adverse effect that impacts quality of life and treatment course. The dose rounding of chemotherapies is a strategy that is commonly used in clinical practice. Nevertheless, the frequency of developed neuropathy in vincristine first-time users and the potential association with dose rounding remains elusive.

METHODS

A retrospective analysis was conducted on patients administered vincristine for the first time between 2016 and 2022 using the King Saud University Medical City (KSUMC) database. Patients were stratified into pediatric and adult groups. Neuropathy frequency, its association with demographic and clinical parameters, and the Impact of dose rounding were assessed using SPSS software version 28.

RESULTS

Approximately 34.6% of patients were diagnosed with neuropathy after vincristine administration. Autonomic neuropathy was common among affected adults and pediatric patients (55.1% and 56.1%, respectively), while cranial neuropathy was more frequent in pediatric patients. Higher BSA (p = 0.038) and Scr (p = 0.044) in the pediatric group, the presence of respiratory comorbidities (p = 0.044), and the use of azole antifungals (p < 0.001) in the adult group were significantly associated with neuropathy episodes. The rounding-up of vincristine doses was significantly associated with increased neuropathy occurrence (p < 0.001), while dose rounding-down was significantly associated with a decrease in neuropathy in both groups of patients (p < 0.001).

CONCLUSIONS

Our findings demonstrate that autonomic neuropathy is the most common vincristine-related neuropathy, regardless of the patient's age. Dose rounding is a significant determinant of vincristine-induced neuropathy in both groups. Further studies are needed to evaluate the variables that exacerbate or prevent neuropathy associated with the first-time use of vincristine.

Soluble epoxide hydrolase inhibition alleviates chemotherapy induced neuropathic pain

Chemotherapy induced peripheral neuropathy (CIPN) is a particularly pernicious form of neuropathy and the associated pain is the primary dose-limiting factor of life-prolonging chemotherapy treatment. The prevalence of CIPN is high and can last long after treatment has been stopped. Currently, late in the COVID-19 pandemic, there are still increased psychological pressures on cancer patients as well as additional challenges in providing analgesia for them. These include the risks of nonsteroidal anti-inflammatory drug (NSAID) analgesics potentially masking early infection symptoms and the immunosuppression of steroidal and opiate based approaches. Even without these concerns, CIPN is often inadequately treated with few therapies that offer significant pain relief. The experiments we report use soluble epoxide hydrolase inhibitors (sEHI) which relieved this intractable pain in preclinical models. Doses of EC5026, an IND candidate intended to treat neuropathic pain, elicited dose dependent analgesic responses in multiple models including platinum-based, taxane, and vinca alkaloid-based CIPN pain in Sprague Dawley rats. At the same time as a class, the sEHI are known to result in fewer debilitating side effects of other analgesics, likely due to their novel mechanism of action. Overall, the observed dose-dependent analgesia in both male and female rats across multiple models of chemotherapy induced neuropathic pain holds promise as a useful tool when translated to the clinic.

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.

Impact of Chemotherapy-Induced Peripheral Neuropathy on Quality of Life in Patients with Advanced Lung Cancer Receiving Platinum-Based Chemotherapy

Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse effect of neurotoxic anticancer drugs that may affect quality of life (QoL). Purpose: The purposes of this study were to: assess the levels of CIPN, anxiety, depression, CIPN–related QoL, and general QoL; and identify the factors related to CIPN–related QoL and general QoL in patients with advanced lung cancer (LC) receiving platinum-based chemotherapy. This cross-sectional study examined patients with advanced LC who received platinum-based chemotherapy from the thoracic oncology inpatient wards of a medical center in northern Taiwan. Structured questionnaires were used to measure patients’ CIPN (European Organization for Research and Treatment of Cancer quality of life questionnaire–chemotherapy–induced peripheral neuropathy 20), anxiety (Hospital Anxiety and Depression Scale Depression Scale [HADS]), depression (HADS), CIPN-related QoL (Functional Assessment of Cancer Therapy /Gynecologic Oncology Group-Neurotoxicity subscale [FACT/GOG–Ntx]), and general QoL (Functional Assessment of Cancer Therapy–General Input [FACT-G]). Of 93 patients with advanced LC, 53.8% reported CIPN–sensory impairment and 47.3% reported CIPN–motor impairment. The most common CIPN symptoms were difficulty getting or maintaining an erection (only for men > 65 years) and difficulty in climbing stairs or getting up out of a chair. Poor CIPN–related QoL (FACT/GOG–Ntx) was associated with more CIPN–sensory and more CIPN–motor impairment. Poor general QoL (FACT-G) was associated with a higher level of depression, a higher level of anxiety, and receipt of more chemotherapy cycles. More than half of LC patients report impairment related to CIPN, calling for holistic treatment to improve QoL.

Vincristine-induced peripheral neuropathy is driven by canonical NLRP3 activation and IL-1β release

Vincristine is an important component of many regimens used for pediatric and adult malignancies, but it causes a dose-limiting sensorimotor neuropathy for which there is no effective treatment. This study aimed to delineate the neuro-inflammatory mechanisms contributing to the development of mechanical allodynia and gait disturbances in a murine model of vincristine-induced neuropathy, as well as to identify novel treatment approaches. Here, we show that vincristine-induced peripheral neuropathy is driven by activation of the NLRP3 inflammasome and subsequent release of interleukin-1β from macrophages, with mechanical allodynia and gait disturbances significantly reduced in knockout mice lacking NLRP3 signaling pathway components, or after treatment with the NLRP3 inhibitor MCC950. Moreover, treatment with the IL-1 receptor antagonist anakinra prevented the development of vincristine-induced neuropathy without adversely affecting chemotherapy efficacy or tumor progression in patient-derived medulloblastoma xenograph models. These results detail the neuro-inflammatory mechanisms leading to vincristine-induced peripheral neuropathy and suggest that repurposing anakinra may be an effective co-treatment strategy to prevent vincristine-induced peripheral neuropathy.

Cold Application and Exercise on Development of Peripheral Neuropathy during Taxane Chemotherapy in Breast Cancer Patients: A Randomized Controlled Trial

Objective

Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of cancer treatment. There is no proven pharmacological application to prevent CIPN. This study was conducted to compare the effects of cold application and exercise on peripheral neuropathy development in patients with breast cancer who received taxane.

Methods

This was a multicenter clinical trial. The study was conducted as a randomized controlled trial on breast cancer patients who had chemotherapy-induced peripheral neuropathy complaints between July 2017 and January 2018 in an outpatient chemotherapy unit of training-research and a university hospital. A standardized, home-based, 12-week exercise program involved progressive strengthening, stretching, and balance exercises. Cold packs were applied for the duration of all 12 taxane infusions and then continued at home. The standard care protocol (information about side effects) of the clinic was used for patients in the control group. Data were collected via Patient Identification Form and CIPN Assessment Tool. Demographic data were evaluated by number and percentage ratios, and the study groups' mean scores were compared by Kruskal-Wallis and Wilcoxon analyses. The data were collected at two time points including baseline (T1) and week 12 (T2).

Results

The study was completed with a total of 90 patients, so that each of the study groups, exercise, cold application, and control groups, included 30 patients. The mean of pre- and posttest results in the cold applied group revealed an increase in hand numbness, weakness, and distress (P < 0.05). However, no significant difference existed between the means of the pre- and the posttests in the exercise group (P = 0.79-0.1). The mean scores of all the symptoms in the control group except the loss of balance increased significantly (P < 0.05). Exercise reduced CIPN symptoms of numbness in hands (P = 0.009) and in the feet (P = 0.005) significantly compared to the cold application and control.

Conclusions

It was found that exercise was more effective than cold application in the management of CIPN.

Tetrodotoxin for Chemotherapy-Induced Neuropathic Pain: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Dose Finding Trial

Tetrodotoxin (TTX) has emerged as a potentially efficacious agent for chemotherapy-induced neuropathic pain (CINP), a prevalent, debilitating condition often resistant to analgesics. This randomized, double-blind, dose-finding study was undertaken to explore safety and trends in efficacy of four TTX doses and to identify a dose for further study. One hundred and twenty-five patients with taxane- or platinum-related CINP received subcutaneous placebo or TTX (7.5 µg twice daily (BID), 15 µg BID, 30 µg once daily (QD), 30 µg BID) for four consecutive days. Primary outcome measure was average patient-reported Numeric Pain Rating Scale (NPRS) score during Days 21–28 post-treatment. Changes in mean NPRS score were not statistically different between cohorts, due to small trial size and influence of a few robust placebo responders. Cumulative responder analysis showed significant difference from placebo with 30 µg BID cohort using the maximum response at any timepoint (p = 0.072), 5-day (p = 0.059), 10-day (p = 0.027), and 20-day (p = 0.071) rolling averages. In secondary quality of life (QOL) outcomes, 30 µg BID cohort also differed significantly from placebo in a number of SF-36 and CIPN20 subscales. Most adverse events (AE) were mild or moderate with oral paresthesia (29.6%) and oral hypoesthesia (24.8%) as most common.

Efficacy and Safety of Acupuncture against Chemotherapy-Induced Peripheral Neuropathy: A Systematic Review and Meta-Analysis

Objective

To determine the effectiveness and safety of acupuncture for chemotherapy-induced peripheral neuropathy. The review has been registered on the “PROSPERO” website; the registration number is CRD42020151654.

Methods

A comprehensive literature search was performed on 7 electronic databases from the time of inception to March 2020. RCTs studies on acupuncture for CIPN compared with medication or sham acupuncture were included. Statistical analysis was carried out using RevMan 5.3.

Results

In total, 19 RCTs covering 1174 patients were enrolled. The results showed that acupuncture significantly increased the effective rate of CIPN compared with medicine and sham acupuncture. And acupuncture had a good effect on the recovery of nerve conduction velocity and improving pain. Among the acupoints involved in the treatment of CIPN, LI4, LI11, ST36, EX10 (Bafeng), and EX-UE 9 (Baxie) were the most commonly used.

Conclusion

The use of acupuncture in the management of CIPN is safe and effective. The most used acupoints for CIPN are LI4, LI11, ST36, EX10 (Bafeng), and EX-UE 9 (Baxie).

Effect of Aromatherapy Massage on Chemotherapy-Induced Peripheral Neuropathic Pain and Fatigue in Patients Receiving Oxaliplatin: An Open Label Quasi-Randomized Controlled Pilot Study

BACKGROUND

Patients receiving oxaliplatin may experience peripheral neuropathic pain and fatigue. Aromatherapy massage, a nonpharmacological method, may help to control these symptoms.

OBJECTIVE

The aim of this open-label, parallel-group, quasi-randomized controlled pilot study was to investigate the effect of aromatherapy massage on chemotherapy-induced peripheral neuropathic pain and fatigue in patients receiving oxaliplatin.

METHODS

Stratified randomization was used to allocate 46 patients to 2 groups: intervention (n = 22) and control (n = 24). Between week 1 and week 6, participants in the intervention group (IG) received aromatherapy massage 3 times a week. There was no intervention in weeks 7 and 8. The control group (CG) received routine care. Neuropathic pain was identified using the Douleur Neuropathique 4 Questions; severity of painful paresthesia was assessed with the numerical rating scale; fatigue severity was identified with the Piper Fatigue Scale.

RESULTS

At week 6, the rate of neuropathic pain was significantly lower in the IG, when compared with the CG. The severity of painful paresthesia based on numerical rating scale in the IG was significantly lower than that in the CG at weeks 2, 4, and 6. At week 8, fatigue severity in the IG was significantly lower when compared with CG (P < .05).

CONCLUSION

Aromatherapy massage may be useful in the management of chemotherapy-induced peripheral neuropathic pain and fatigue.

IMPLICATIONS FOR PRACTICE

This pilot study suggests that aromatherapy massage may be useful to relieve neuropathic pain and fatigue. However, there is a need for further clinical trials to validate the results of this study.

Incidence of peripheral neuropathy associated with eribulin mesylate versus vinorelbine in patients with metastatic breast cancer: sub-group analysis of a randomized phase III study

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is one of the most significant neurologic complications of chemotherapy, impacting patient's behavior and quality of life. CIPN is mostly sensory, with rare incidences of autonomic dysfunction and other neuropathy.

METHODS

We conducted a single-center sub-group analysis of patients with metastatic breast cancer enrolled in a phase III study (NCT02225470) set up to compare eribulin mesylate (1.4 mg/m² on days 1 and 8 every 21 days) with vinorelbine (25 mg/m² on days 1, 8, and 15 every 21 days). The analysis investigated incidence of peripheral neuropathy, time to onset of neuropathy, and safety.

RESULTS

Our analysis included 110 women with a mean age of 50.7 (SD = 10.9). The median accumulated dose of eribulin was 11.2 mg/m² and 125.0 mg/m² for vinorelbine. Among patients in the eribulin group, a performance status (ECOG PS) of 2 was correlated with peripheral sensory neuropathy (p = 0.015), and accumulated eribulin dose (≥ 10 mg/m²) was associated with all neuropathy and peripheral sensory neuropathy (p = 0.003 and p = 0.007, respectively). In the vinorelbine group, patient age (≥ 65 years) was positively associated with all neuropathy (p = 0.043). The time to onset of neuropathy appeared to be longer for eribulin versus vinorelbine (35.3 vs. 34.6 weeks; p = 0.046), with a significantly higher incidence of autonomic neuropathy at weeks 2 and 10 observed among patients receiving vinorelbine (p = 0.008 and p = 0.043, respectively).

CONCLUSION

Vinorelbine is associated with a higher incidence of autonomic neuropathy than eribulin in patients with metastatic breast cancer. Furthermore, the onset of neurotoxicity appears to occur earlier with vinorelbine than eribulin.

Incidence of vincristine induced neurotoxicity in children with acute lymphoblastic leukemia and its correlation with nutritional deficiencies

Injection vincristine is an important component of therapy for acute lymphoblastic leukemia (ALL). An important adverse effect of vincristine is neurotoxicity. The incidence of this adverse effect is well studied. The present was undertaken to determine the incidence of vincristine-induced neurotoxicity in children with ALL after the induction of remission phase of chemotherapy and to ascertain its correlation with undernutrition, vitamin B12, folate and iron deficiency. Thirty children (1-18 years) with ALL were enrolled at the commencement of chemotherapy. The electrophysiological evaluation was done at baseline and repeated after four doses of vincristine (1.5 mg/m²/dose). Clinical evaluation was done regularly. Anthropometry and serum B12, folate and ferritin levels were assessed at baseline. Twelve children over a 4-week period of observation had peripheral neuropathy clinically. The autonomic system was most commonly involved followed by motor and sensory system respectively. On electrophysiological testing, half of the patients had evidence of neuropathy. Micronutrient deficiencies were present in a significant number of patients-63.3% had a B12 deficiency, 20% were deficient in folate and 43.3% in iron. The incidence of vincristine-induced neuropathy in patients with/without these micro-nutrient deficiencies was not statistically significantly different. Vincristine-induced neuropathy is common in Indian children with ALL. The present study did not find any correlation between the occurrences of vincristine-induced neuropathy and nutritional deficiencies. Larger studies are warranted to evaluate the contribution of micronutrient deficiencies to the development of peripheral neuropathy in childhood ALL.

Molecular Mechanisms of the Sense of Touch: An Overview of Mechanical Transduction and Transmission in Merkel Discs of Whisker Hair Follicles and Some Clinical Perspectives

The Merkel disc is a main type of tactile end organs for sensing gentle touch and is essential for sophisticated sensory tasks including social interaction, environmental exploration, and tactile discrimination. Recent studies have shown that Merkel cells are primary sites of mechanotransduction using Piezo2 channels as a molecular transducer in Merkel discs. Furthermore, tactile stimuli trigger serotonin release from Merkel cells to excite their associated whisker Aβ-afferent endings and transmit tactile signals. The tactile transduction and transmission at Merkel discs may have important clinical implications in sensory dysfunctions such as the loss of tactile sensitivity and tactile allodynia seen in patients who have diabetes and inflammatory diseases and undergo chemotherapy.

Polyneuropathies

BACKGROUND

Polyneuropathies (peripheral neuropathies) are the most common type of disorder of the peripheral nervous system in adults, and specifically in the elderly, with an estimated prevalence of 5-8%, depending on age. The options for treatment depend on the cause, which should therefore be identified as precisely as possible by an appropriate diagnostic evaluation.

METHODS

This review is based on the current guidelines and on large-scale cohort studies and randomized, controlled trials published from 2000 to 2017, with an emphasis on non-hereditary types of polyneuropathy, that were retrieved by a selective search in PubMed.

RESULTS

Diabetes is the most common cause of polyneuropathy in Europe and North America. Alcohol-associated polyneuropathy has a prevalence of 22-66% among persons with chronic alcoholism. Because of the increasing prevalence of malignant disease and the use of new chemotherapeutic drugs, chemotherapy-induced neuropathies (CIN) have gained in clinical importance; their prevalence is often stated to be 30-40%, with high variation depending on the drug(s) and treatment regimen used. Polyneuropathy can also arise from genetic causes or as a consequence of vitamin deficiency or overdose, exposure to toxic substances and drugs, and a variety of immunological processes. About half of all cases of polyneu - ropathy are associated with pain. Neuropathic pain can be treated symptomatically with medication. Exercise, physiotherapy, and ergotherapy can also be beneficial, depending on the patient's symptoms and functional deficits.

CONCLUSION

A timely diagnosis of the cause of polyneuropathy is a prerequisite for the initiation of appropriate specific treatment. Patients with severe neuropathy of unidentified cause should be referred to a specialized center for a thorough diagnostic evaluation.

Aspects of vincristine-induced neuropathy in hematologic malignancies: a systematic review

PURPOSE

Vincristine is widely used as anticancer therapy for a variety of hematological malignancies. The treatment is limited by progressive vincristine-induced neuropathy, possibly including both peripheral sensory and motor nerves, autonomic nervous functions, and the central nervous system. This dose-limiting side-effect can diminish quality of life and, furthermore, cause discontinuation of vincristine treatment. The present review elucidates the current knowledge regarding vincristine-induced neuropathy in hematologic malignancies, focusing on neuropathy assessment, clinical and molecular predictive markers, drug-drug interference, prevention, and treatment.

METHODS

This review is conducted by a systematic search strategy for the identification of relevant literature in the PubMed and Embase databases.

RESULTS

No clinical parameters displayed convincing potential as predictors of vincristine-induced neuropathy; however, preexisting neuropathy was consistently reported to be associated with an increased risk of neurotoxicity. In contrast, molecular markers, including polymorphisms in genes involved in the pharmacodynamics and pharmacokinetics of vincristine, displayed great potential as predictive markers of neuropathy incidence and severity. Furthermore, antifungal drugs, such as itraconazole and voriconazole, decrease the metabolism of vincristine and consequently lead to severe neuropathy when co-administered with vincristine, underscoring why fluconazole should be the antifungal drug of choice.

CONCLUSION

Reports from the 71 included studies clearly emphasize the lack of consistency in neuropathy assessment, grading systems, and reporting, making it difficult to interpret results between studies. Thus, truer clinical and molecular markers could emerge if the consistency of neuropathy detection and reporting increases by the use of conventional standardized neuropathy assessment tools and grading scales.

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.

Oncology Acupuncture for Chronic Pain in Cancer Survivors: A Reflection on the American Society of Clinical Oncology Chronic Pain Guideline

Chronic pain syndromes associated with cancer treatment are common but difficult to manage. The American Society of Clinical Oncology recently published a practice guideline to address the unmet needs of cancer survivors, Management of Chronic Pain in Survivors of Adult Cancers, which stresses the importance of implementing integrative therapies including acupuncture. This review focuses on randomized clinical trials of acupuncture for chronic pain in cancer survivors, including its use in chemotherapy-induced peripheral neuropathy, aromatase inhibitor-associated arthralgia, and post neck dissection pain, and provides future directions of oncology acupuncture research in cancer survivorship. The features of oncology acupuncture are also discussed.

Factors Influencing Lower Urinary Tract Symptoms in Advanced Cancer Patients With Chemotherapy-Induced Peripheral Neuropathy

Purpose

This study aimed to investigate the severity of lower urinary tract symptoms (LUTS) and to identify factors that influenced LUTS in advanced cancer patients with chemotherapy-induced peripheral neuropathy (CIPN).

Methods

This cross-sectional study included a total of 158 advanced cancer patients with CIPN. A structured questionnaire including the International Prostate Symptom Score and the Functional Assessment of Cancer Therapy/Gynecology Oncology Group/Neurotoxicity scale was used. Data were analyzed using the Pearson correlation coefficient and multiple regression analysis.

Results

Nocturia was the most prevalent LUTS. A positive relationship was found between CIPN symptoms and LUTS. The duration of cancer diagnosis and the severity of CIPN were key factors that influenced LUTS.

Conclusions

The severity of CIPN symptoms was the most important predictor of LUTS. Nurses’ care for advanced cancer patients should incorporate a comprehensive health assessment, which includes a history of treatment and physical neuropathic symptoms, for any patient complaining of CIPN symptoms.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

The Content Validity of a Chemotherapy-Induced Peripheral Neuropathy Patient-Reported Outcome Measure

PURPOSE/OBJECTIVES

To test the content validity of a 16-item version of the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Chemotherapy-Induced Peripheral Neuropathy (QLQ-CIPN20). 
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RESEARCH APPROACH

Cross-sectional, prospective, qualitative design. 
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SETTING

Six outpatient oncology clinics within the University of Michigan Health System's comprehensive cancer center in Ann Arbor. 
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PARTICIPANTS

25 adults with multiple myeloma or breast, gynecologic, gastrointestinal, or head and neck malignancies experiencing peripheral neuropathy caused by neurotoxic chemotherapy. 
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METHODOLOGIC APPROACH

Cognitive interviewing methodology was used to evaluate the content validity of a 16-item version of the QLQ-CIPN20 instrument.
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FINDINGS

Minor changes were made to three questions to enhance readability. Twelve questions were revised to define unfamiliar terminology, clarify the location of neuropathy, and emphasize important aspects. One question was deleted because of clinical and conceptual redundancy with other items, as well as concerns regarding generalizability and social desirability. 
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INTERPRETATION

Cognitive interviewing methodology revealed inconsistencies between patients' understanding and researchers' intent, along with points that required clarification to avoid misunderstanding. 
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IMPLICATIONS FOR NURSING

Patients' interpretations of the instrument's items were inconsistent with the intended meanings of the questions. One item was dropped and others were revised, resulting in greater consistency in how patients, clinicians, and researchers interpreted the items' meanings and improving the instrument's content validity. Following additional revision and psychometric testing, the QLQ-CIPN20 could evolve into a gold-standard CIPN patient-reported outcome measure.

Association of CYP3A5 Expression and Vincristine Neurotoxicity in Pediatric Malignancies in Turkish Population

Vincristine is a widely used chemotherapeutic agent in the treatment of childhood malignancies. Neuropathy is the most common adverse effect. CYP3A4 and CYP3A5 enzymes of cytochrome p450 enzyme system are responsible in vincristine metabolism. Genetic polymorphism may alter the vincristine metabolism and the neurotoxicity rate. In this study, distribution of CYP3A5 alleles among Turkish children with malignancies, relation between CYP3A5 genotype and neurotoxicity rates, as well as severity and duration of neuropathy and total vincristine doses were investigated. Patient group consisted of 115 patients (age, 1 to 17 y) with acute lymphoblastic leukemia and solid tumors, who were treated with vincristine consisting chemotherapy protocols. Control group consisted of 50 children without any neurological symptom or disorders. All patient files were reviewed for presence and severeness of neurotoxicity symptoms. Blood samples were obtained and CYP3A5 genotypes were analyzed. Neurotoxicity occurred in 20.8% of patients. Although it was found to occur more frequently after 4 doses of vincristine, and rates were higher in the low-dose vincristine group suggesting other contributing factors. Although neurotoxicity rate in the CYP3A5*1/*3 genotype was 17.6%, it was 21.6% in the CYP3A5*3/*3 genotype and the difference was not statistically significant (P<0.05). This study suggested that vincristine-related neurotoxicity is dose-independent and genotype is not the only causative factor in the occurrence of neurotoxicity in these patients.

The effect of intraperitoneal chemotherapy on early pain hyperalgesia in patients following elective laparoscopic transabdominal resection of rectal cancer

Background

Chemotherapy has been associated with hyperalgesia. This prospective study was designed to investigate the effect of intraperitoneal chemotherapy with lobaplatin on post-operative pain intensity and sufentanil requirements after laparoscopic transabdominal resection of rectal cancer.

Methods

Eighty subjects (40 subjects treated with intraperitoneal chemotherapy and 40 subjects without chemotherapy treatment) scheduled for laparoscopic transabdominal resection of rectal cancer were included in this study. All subjects received standardized anesthetic and patient-controlled analgesia using sufentanil for 72 h post-surgery, as the only analgesics. Pain intensity scores, cumulative sufentanil requirements and side effects were recorded until 72 h post-surgery.

Results

Following intraperitoneal chemotherapy, patients had a significantly higher total post-operative sufentanil requirement (193 μg vs. 142 μg; P = 0.008), significantly higher verbal rating scale post-surgery pain intensity scores at rest and with coughing (P < 0.05), and a significantly worse functional activity score (P < 0.05) over 72 h, compared with those without intraperitoneal chemotherapy. There were no post-operative differences in the incidence of side-effects (post-operative nausea [P = 0.189], vomiting [P = 0.311], pruritus [P = 0.263], respiratory depression [P = 1.000], and dizziness [P = 0.712]) between the two groups.

Conclusion

Intraperitoneal chemotherapy is associated with significantly increased post-operative sufentanil requirements and pain intensity, suggesting chemotherapy-associated hyperalgesia.

Pilot Testing a Web-Based System for the Assessment and Management of Chemotherapy-Induced Peripheral Neuropathy

Because numerous barriers hinder the assessment and management of chemotherapy-induced peripheral neuropathy in clinical practice, the Carevive Care Planning System, a novel Web-based platform, was developed to address these barriers. It provides patients an opportunity to report their symptoms before their clinic visit and generates customizable care plans composed of evidence-based management strategies. The purpose of this study was to evaluate patient and provider perspectives of feasibility, usability, acceptability, and satisfaction with the Carevive platform. We used a single-arm, pretest/posttest, prospective design and recruited 25 women with breast cancer who were receiving neurotoxic chemotherapy and six advanced practice providers from an academic hospital. At three consecutive clinical visits, patients reported their neuropathy symptoms on a tablet via the Carevive system. The Diffusion of Innovations Theory served as an overarching evaluation framework. The Carevive platform was feasible to use. However, patients had higher ratings of usability, acceptability, and satisfaction with the platform than did the providers, who disliked the amount of time required to use the platform and had difficulty logging into Carevive. If issues regarding provider dissatisfaction can be addressed, the Carevive platform may aid in the screening of neuropathy symptoms and facilitate the use of evidence-based management strategies.

Electronic versus paper-pencil methods for assessing chemotherapy-induced peripheral neuropathy

PURPOSE

The aim of this study is to examine and compare with the validated, paper/pencil European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Chemotherapy-Induced Peripheral Neuropathy Scale (QLQ-CIPN20), the psychometric properties of three electronically administered patient reported outcome (PRO) measures of chemotherapy-induced peripheral neuropathy (CIPN): (1) the two neuropathy items from the National Cancer Institute's Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE), (2) the QLQ-CIPN20, and (3) the 0-10 Neuropathy Screening Question (NSQ).

METHODS

We employed a descriptive, cross-sectional design and recruited 25 women with breast cancer who were receiving neurotoxic chemotherapy at an academic hospital. Participants completed the paper/pencil QLQ-CIPN20 and electronic versions of the QLQ-CIPN20, PRO-CTCAE, and NSQ. Internal consistency reliability, intraclass correlation, and concurrent and discriminant validity analyses were conducted.

RESULTS

The alpha coefficients for the electronic QLQ-CIPN20 sensory and motor subscales were 0.76 and 0.75. Comparison of the electronic and paper/pencil QLQ-CIPN20 subscales supported mode equivalence (intraclass correlation range >0.91). Participants who reported the presence of numbness/tingling via the single-item NSQ reported higher mean QLQ-CIPN20 sensory subscale scores (p < 0.001). PRO-CTCAE neuropathy severity and interference items correlated well with the QLQ-CIPN20 electronic and paper/pencil sensory (r = 0.76; r = 0.70) and motor (r = 0.55; r = 0.62) subscales, and with the NSQ (r = 0.72; r = 0.44).

CONCLUSION

These data support the validity of the electronically administered PRO-CTCAE neuropathy items, NSQ, and QLQ-CIPN20 for neuropathy screening in clinical practice. The electronic and paper/pencil versions of the QLQ-CIPN can be used interchangeably based on evidence of mode equivalence.

[Chemotherapy-induced peripheral neuropathy and neuropathic pain]

The perception of the media is that chemotherapy is mainly associated with nausea, vomiting and hair loss. In the longer term the development of peripheral neuropathy, i.e. chemotherapy-induced peripheral neuropathy (CIPN) is often more important for patients. The CIPN represents a side effect of many antineoplastic substances with severe functional impairment and its prevention and treatment is an important task. In addition to many interventions, which have been shown to be ineffective, physiotherapeutic measures and possibly the prophylactic application of cold are helpful for prevention. Randomized studies on the treatment of painful CIPN provided positive data for duloxetine and to a lesser extent for venlafaxine.

Women Treated for Breast Cancer Experiences of Chemotherapy-Induced Pain: Memories, Any Present Pain, and Future Reflections

BACKGROUND

Breast cancer survivors make up a growing population facing treatment that poses long-standing adverse effects including chemotherapy-related body function changes and/or pain. There is limited knowledge of patients' lived experiences of chemotherapy-induced pain (CHIP).

OBJECTIVE

The aim of this study was to explore CHIP and any long-standing pain experiences in the lifeworld of breast cancer survivors.

METHODS

Fifteen women participated in a follow-up interview a year after having experienced CHIP. They were interviewed from a lifeworld perspective; the interviews were analyzed through guided phenomenology reflection.

RESULTS

A past perspective: CHIP is often described in metaphors, leads to changes in a patient's lifeworld, and impacts lived time. The women become entirely dependent on others but at the same time feel isolated and alone. Existential pain was experienced as increased vulnerability. Present perspective: Pain engages same parts of the body, but at a lower intensity than during CHIP. The pain creates time awareness. Expected normality in relationships/daily life has not yet been achieved, and a painful existence emerges in-between health and illness. Future perspective: There are expectations of pain continuing, and there is insecurity regarding whom to turn to in such cases. A painful awareness emerges about one's own and others' fragile existence.

CONCLUSIONS

Experiencing CHIP can impact the lifeworld of women with a history of breast cancer. After CHIP, there are continued experiences of pain that trigger insecurity about whether one is healthy.

IMPLICATIONS FOR PRACTICE

Cancer survivors would likely benefit from communication and information about and evaluation of CHIP.

Vitamin E does not decrease the incidence of chemotherapy-induced peripheral neuropathy: a meta-analysis

Aim of this study

Chemotherapy-induced peripheral neuropathy (CIPN) is a major complication of cancer patients with chemotherapy. Although many interventions have been evaluated in previous studies, findings are controversial. The aim of this meta-analysis is to assess the efficacy of vitamin E supplementation in preventing CIPN.

Material and methods

The electronic databases MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were systematically searched from their inception to December 31, 2013 to identify relevant randomised controlled trials. Two reviewers independently scanned and extracted the data of included studies. Review Manager 5.2 was used to analyse data.

Results

Six articles involving 353 patients were included in meta-analysis. The results showed that vitamin E supplementation did not appear to significantly decrease the incidence of CIPN (relative risk (RR), 0.55; 95% confidence interval (CI), 0.29 to 1.05; p = 0.07), with significant heterogeneity (I² = 77%). However, Vitamin E supplementation can significantly prevent cisplatin associated neurotoxicity (RR, 0.31; 95%CI, 0.17 to 0.58; p = 0.0002), with no heterogeneity (I² = 0%).

Conclusions

Vitamin E administration dose not decrease the incidence of CIPN. However, additional randomised controlled trials using large samples are needed to confirm the role of vitamin E supplementation.

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.

The functional capacity and quality of life of women with advanced breast cancer

BACKGROUND

The rehabilitation needs of patients with metastatic breast cancer (MBC) are poorly studied. The primary aim of the study was to evaluate the functional capacity of women with MBC and quality of life (QoL).

METHODS

The present study is an open, non-randomized, prospective cross-sectional observation study. The functional capacity of 128 MBC patients with ongoing cancer treatments, were studied in Helsinki University Hospital (HUS): Peak expiratory flow (PEF), dynamic and static balance, 6 minute walking distance (6MWD), 10 meter walking, sit-to-stand test, repeated squat, grip strength, shoulder movement, pain, and QoL by Beck's depression scale (BDI), health assessment questionnaire (HAQ), RAND SF-36 and EORTC QLQ-30 items.

RESULTS

The walking capacity was compromised in half and the strength of the lower extremities in one-third of the patients. PEF was below the normal reference in 55 %, static balance in 62 % and dynamic balance in 73 % (≤60 year olds) and 81 % (≥61 year olds). The grip power was lowered in 44/30 % of the patients (right/left) and the shoulder movement was restricted in 30 %. Some disability in physical functioning experienced 55 % (HAQ) and 37 % felt depressive (BDI). The QoL (RAND SF-36) was poor especially in the field of physical, role and social functioning and bodily pain (<0.001). Pain, depression, and a poor 6MWD results independently determined the physical component of QoL (p < 0.001).

CONCLUSIONS

The functional capacity of patients with MBC was significantly lowered. This, in association with distressing symptoms like pain and depression causes a vicious circle further leading to functional disabilities and impaired QoL.

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

Duloxetine is an effective treatment for oxaliplatin-induced painful chemotherapy-induced peripheral neuropathy (CIPN). However, predictors of duloxetine response have not been adequately explored. The objective of this secondary and exploratory analysis was to identify predictors of duloxetine response in patients with painful oxaliplatin-induced CIPN. Patients (N = 106) with oxaliplatin-induced painful CIPN were randomised to receive duloxetine or placebo. Eligible patients had chronic CIPN pain and an average neuropathic pain score ≥4/10. Duloxetine/placebo dose was 30 mg/day for 7 days, then 60 mg/day for 4 weeks. The Brief Pain Inventory-Short Form and the EORTC QLQ-C30 were used to assess pain and quality of life, respectively. Univariate and multiple logistic regression analyses were performed to identify demographic, physiologic and psychological predictors of duloxetine response. Higher baseline emotional functioning predicted duloxetine response (≥30% reduction in pain; OR 4.036; 95% CI 0.999-16.308; p = 0.050). Based on the results from a multiple logistic regression using patient data from both the duloxetine and placebo treatment arms, duloxetine-treated patients with high emotional functioning are more likely to experience pain reduction (p = 0.026). In patients with painful, oxaliplatin-induced CIPN, emotional functioning may also predict duloxetine response. ClinicalTrials.gov, Identifier NCT00489411.

Natural products and complementary therapies for chemotherapy-induced peripheral neuropathy: A systematic review

Chemotherapy-induced peripheral neuropathy (CIPN) is a serious dose-limiting side-effect without any FDA-approved treatment option. Prior reviews focus mostly on pharmacological interventions, but nonpharmaceutical interventions have also been evaluated. A Web of Science and PubMed database search to identify relevant RCTs from January 2005 to May 2015 included the terms: CIPN, cancer; and supplements, vitamin E, goshajinkigan, kampo, acetyl-L-carnitine, carnitine, alpha-lipoic acid, omega-3, glutamine, or glutamate; or massage, acupuncture, mind-body practice, yoga, meditation, Tai-Chi, physical activity, or exercise. Of 1465 publications screened, 12 RCTs evaluated natural products and one evaluated electroacupuncture. Vitamin E may help prevent CIPN. L-Glutamine, goshajinkigan, and omega-3 are also promising. Acetyl-L-carnitine may worsen CIPN and alpha-lipoic acid activity is unknown. Electroacupuncture was not superior to placebo. No RCTs were published regarding other complementary therapies, although some studies mention positive incidental findings. Natural products and complementary therapies deserve further investigation, given the lack of effective CIPN interventions.

Cancer treatment-related neuropathic pain syndromes--epidemiology and treatment: an update

Cancer treatment-related chronic neuropathic pain (NP) is a pervasive and distressing problem that negatively influences function and quality of life for countless cancer survivors. It occurs because of cancer treatment-induced damage to peripheral and central nervous system structures. NP becomes chronic when pain signal transmission persists, eventually sensitizing neurons in the dorsal horn and other pain-processing regions in the central nervous system. Frequently overlooked, NP due to cancer treatment has been understudied. Consequently, only a few pharmacologic interventions have been shown to be effective based on the results of randomized controlled trials. Future research designed to explore pathophysiologic mechanisms and effective mechanism-targeted interventions is sorely needed.

Pharmacological management of chronic neuropathic pain: revised consensus statement from the Canadian Pain Society

BACKGROUND

Neuropathic pain (NeP), redefined as pain caused by a lesion or a disease of the somatosensory system, is a disabling condition that affects approximately two million Canadians.

OBJECTIVE

To review the randomized controlled trials (RCTs) and systematic reviews related to the pharmacological management of NeP to develop a revised evidence-based consensus statement on its management.

METHODS

RCTs, systematic reviews and existing guidelines on the pharmacological management of NeP were evaluated at a consensus meeting in May 2012 and updated until September 2013. Medications were recommended in the consensus statement if their analgesic efficacy was supported by at least one methodologically sound RCT (class I or class II) showing significant benefit relative to placebo or another relevant control group. Recommendations for treatment were based on the degree of evidence of analgesic efficacy, safety and ease of use.

RESULTS

Analgesic agents recommended for first-line treatments are gabapentinoids (gabapentin and pregabalin), tricyclic antidepressants and serotonin noradrenaline reuptake inhibitors. Tramadol and controlled-release opioid analgesics are recommended as second-line treatments for moderate to severe pain. Cannabinoids are now recommended as third-line treatments. Recommended fourth-line treatments include methadone, anticonvulsants with lesser evidence of efficacy (eg, lamotrigine, lacosamide), tapentadol and botulinum toxin. There is support for some analgesic combinations in selected NeP conditions.

CONCLUSIONS

These guidelines provide an updated, stepwise approach to the pharmacological management of NeP. Treatment should be individualized for each patient based on efficacy, side-effect profile and drug accessibility, including cost. Additional studies are required to examine head-to-head comparisons among analgesics, combinations of analgesics, long-term outcomes and treatment of pediatric, geriatric and central NeP.

Vincristine-induced neuropathy in childhood ALL (acute lymphoblastic leukemia) survivors: prevalence and electrophysiological characteristics

The prevalence and the burden of vincristine-induced neuropathy have been poorly documented in childhood acute lymphoblastic leukemia survivors. This cross-sectional study was carried out at a tertiary care center in northern India from October 2011 to June 2012. Eighty consecutive acute lymphoblastic leukemia survivors aged 5 to 18 years, within 3 years of completion of their chemotherapy, were enrolled. After clinical evaluation, detailed nerve conduction studies were performed and the reduced version of the Total Neuropathy Score was calculated. The mean age at the time of evaluation was 11.2 ± 3.2 years. 33.75% had neuropathy electrophysiologically. Symmetric motor axonal polyneuropathy was the most common pattern of involvement seen in 19 (23.8%) children. There was significant improvement with time, as revealed by lower prevalence of neuropathy with increasing interval following vincristine injection. 33.75% of the children had Reduced version of Total Neuropathy Score ≥ 1.

Toxic and drug-induced peripheral neuropathies: updates on causes, mechanisms and management

PURPOSE OF REVIEW

This review discusses publications highlighting current research on toxic, chemotherapy-induced peripheral neuropathies (CIPNs), and drug-induced peripheral neuropathies (DIPNs).

RECENT FINDINGS

The emphasis in clinical studies is on the early detection and grading of peripheral neuropathies, whereas recent studies in animal models have given insights into molecular mechanisms, with the discovery of novel neuronal, axonal, and Schwann cell targets. Some substances trigger inflammatory changes in the peripheral nerves. Pharmacogenetic techniques are underway to identify genes that may help to predict individuals at higher risk of developing DIPNs. Several papers have been published on chemoprotectants; however, to date, this approach has not been shown effective in clinical trials.

SUMMARY

Both length and nonlength-dependent neuropathies are encountered, including small-fiber involvement. The introduction of new diagnostic techniques, such as excitability studies, skin laser Doppler flowmetry, and pharmacogenetics, holds promise for early detection and to elucidate underlying mechanisms. New approaches to improve functions and quality of life in CIPN patients are discussed. Apart from developing less neurotoxic anticancer therapies, there is still hope to identify chemoprotective agents (erythropoietin and substances involved in the endocannabinoid system are promising) able to prevent or correct painful CIPNs.

Spinal changes of a newly isolated neuropeptide endomorphin-2 concomitant with vincristine-induced allodynia

Chemotherapy-induced neuropathic pain (CNP) is the major dose-limiting factor in cancer chemotherapy. However, the neural mechanisms underlying CNP remain unclear. There is increasing evidence implicating the involvement of spinal endomorphin-2 (EM2) in neuropathic pain. In this study, we used a vincristine-evoked rat CNP model displaying mechanical allodynia and central sensitization, and observed a significant decrease in the expression of spinal EM2 in CNP. Also, while intrathecal administration of exogenous EM2 attenuated allodynia and central sensitization, the mu-opioid receptor antagonist β-funaltrexamine facilitated these events. We found that the reduction in spinal EM2 was mediated by increased activity of dipeptidylpeptidase IV, possibly as a consequence of chemotherapy-induced oxidative stress. Taken together, our findings suggest that a decrease in spinal EM2 expression causes the loss of endogenous analgesia and leads to enhanced pain sensation in CNP.

A phase III randomized, placebo-controlled study of topical amitriptyline and ketamine for chemotherapy-induced peripheral neuropathy (CIPN): a University of Rochester CCOP study of 462 cancer survivors

PURPOSE

Chemotherapy-induced peripheral neuropathy (CIPN) occurs in as high as 70% of patients receiving certain types of chemotherapy agents. The FDA has yet to approve a therapy for CIPN. The aim of this multicenter, phase III, randomized, double-blind, placebo-controlled trial was to investigate the efficacy of 2% ketamine plus 4% amitriptyline (KA) cream for reducing CIPN.

METHODS

Cancer survivors who completed chemotherapy at least 1 month prior and had CIPN (>4 out of 10) were enrolled (N=462). CIPN was assessed using average scores from a 7-day daily diary that asks patients to rate the average "pain, numbness, or tingling in [their] hands and feet over the past 24 h" on an 11-point numeric rating scale at baseline and 6 weeks post intervention. ANCOVA was used to measure differences in 6-week CIPN with effects including baseline CIPN, KA treatment arm, and previous taxane therapy (Y/N).

RESULTS

The KA treatment showed no effect on 6-week CIPN scores (adjusted mean difference=-0.17, p=0.363).

CONCLUSIONS

This study suggests that KA cream does not decrease CIPN symptoms in cancer survivors.