Mechanisms, Mediators, and Moderators of the Effects of Exercise on Chemotherapy-Induced Peripheral Neuropathy

Exploring Chemotherapy-Induced Peripheral Neuropathy Management Practice Patterns Among Oncology Clinicians

OBJECTIVES

Approximately 60% of cancer survivors receiving neurotoxic chemotherapy experience chemotherapy-induced peripheral neuropathy (CIPN) (eg, hand and foot numbness, tingling, or pain). There is only one recommended pharmacological treatment (duloxetine) and one modestly beneficial nonpharmacological treatment (exercise) for CIPN. However, data suggest national guideline recommendations are not routinely practiced. Further, less is known about nurses' CIPN management practices. The purpose of this convergent mixed methods study was to explore oncology clinicians' self-reported practices and perceptions regarding CIPN prevention and management.

METHODS

Oncology clinicians at three cancer centers completed a survey about their recommendations for CIPN prevention and management in practice. A subset of clinicians also participated in a semi-structured interview to explore their perspectives of and motivations for implementing CIPN assessment, prevention, and management in practice. Quantitative data were described (eg, frequency or median) and qualitative data were analyzed using inductive content analysis.

RESULTS

This study (N = 44 survey responses; n = 9 interviews) resulted in four themes: (1) clinicians primarily recommend gabapentin for CIPN management and often observe cryotherapy used for CIPN prevention, but these interventions are complicated by discomfort, intolerable side effects, and efficacy concerns; (2) clinicians perceive CIPN as troublesome and desire additional information and resources regarding CIPN prevention and management; (3) CIPN-related education provided by clinicians may be limited by patient retention of the amount of education received about cancer treatment and other factors; (4) clinicians use subjective CIPN assessment to screen at each visit for common CIPN symptoms (eg, numbness or tingling) and the impact of symptoms on day-to-day activities.

CONCLUSIONS

Discrepancies persist between evidence-based guidelines on CIPN management and current oncology clinician practices.

IMPLICATIONS FOR NURSING PRACTICE

Clinician involvement is needed when developing education and resources to help oncology clinicians provide the most evidence-based care to potentially prevent and manage their patients' CIPN.

Pilot trial testing the effects of exercise on chemotherapy-induced peripheral neurotoxicity (CIPN) and the interoceptive brain system

PURPOSE

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a prevalent, dose-limiting, tough-to-treat toxicity involving numbness, tingling, and pain in the extremities with enigmatic pathophysiology. This randomized controlled pilot study explored the feasibility and preliminary efficacy of exercise during chemotherapy on CIPN and the role of the interoceptive brain system, which processes bodily sensations.

METHODS

Nineteen patients (65 ± 11 years old, 52% women; cancer type: breast, gastrointestinal, multiple myeloma) starting neurotoxic chemotherapy were randomized to 12 weeks of exercise (home-based, individually tailored, moderate intensity, progressive walking, and resistance training) or active control (nutrition education). At pre-, mid-, and post-intervention, we assessed CIPN symptoms (primary clinical outcome: CIPN-20), CIPN signs (tactile sensitivity using monofilaments), and physical function (leg strength). At pre- and post-intervention, we used task-free ("resting") fMRI to assess functional connectivity in the interoceptive brain system, involving the salience and default mode networks.

RESULTS

The study was feasible (74-89% complete data across measures) and acceptable (95% retention). We observed moderate/large beneficial effects of exercise on CIPN symptoms (CIPN-20, 0-100 scale: - 7.9 ± 5.7, effect size [ES] =  - 0.9 at mid-intervention; - 4.8 ± 7.3, ES = - 0.5 at post-intervention), CIPN signs (ES =  - 1.0 and - 0.1), and physical function (ES = 0.4 and 0.3). Patients with worse CIPN after neurotoxic chemotherapy had lower functional connectivity within the default mode network (R2 = 40-60%) and higher functional connectivity within the salience network (R2 = 20-40%). Exercise tended to increase hypoconnectivity and decrease hyperconnectivity seen in CIPN (R2 = 12%).

CONCLUSION

Exercise during neurotoxic chemotherapy is feasible and may attenuate CIPN symptoms and signs, perhaps via changes in interoceptive brain circuitry. Future work should test for replication with larger samples.

TRIAL REGISTRATION

Registered Jan 2017 on ClinicalTrials.gov as NCT03021174.

Digitizing Survivorship Care Plans Through the POST-Treatment Health Outcomes of Cancer Survivors (POSTHOC) Mobile App: Protocol for a Phase II Randomized Controlled Trial

BACKGROUND

Survivorship care plans (SCPs) are provided at the completion of cancer treatment to aid in the transition from active treatment to long-term survivorship. They describe the details of a patient's diagnosis and treatment and offer recommendations for follow-up appointments, referrals, and healthy behaviors. The plans are currently paper-based and become outdated as soon as a patient's health status changes. There is a need to digitize these plans to improve their accessibility, modifiability, and longevity. With current technology, SCPs can be linked to mobile devices and activity trackers so that patients can track health behaviors and compare them to their clinical goals, taking charge of their own health.

OBJECTIVE

A mobile app, POSTHOC (POST-Treatment Health Outcomes of Cancer Survivors), that digitizes the SCP was developed, with goals of integrating it with wearable technologies and electronic medical records. Herein, we are conducting a randomized controlled trial that evaluates the POSTHOC app versus the traditional SCP on total symptom burden in the early posttreatment period.

METHODS

We will recruit 54 patients who have recently completed curative therapy for cancer (any type) in person and remotely. They will be randomized 2:1, POSTHOC:usual care (unblinded). Those randomized to the POSTHOC group will receive their SCP via the app and will choose to focus on nutrition or exercise for the duration of the study based on their individual plan and personal preferences. Those randomized to the control group will get a paper-based plan. At baseline, 6 weeks, and 12 weeks, we will evaluate patient-reported outcomes, including total symptom burden (web-based questionnaire), diet (24-hour Automated Self-Administered [ASA24]), and physical activity (Fitbit Charge 6 [Google LLC]). We will also collect quantitative and qualitative feedback on the usability of the app from those in the POSTHOC arm to improve the app for future implementation studies, with a specific focus on patient-provider communication. For feasibility, we will calculate the percentage of patients who used the POSTHOC app at least 3 times per week. We will use linear mixed models to evaluate the effects of the POSTHOC app versus those of usual care on other outcomes at weeks 6 and 12.

RESULTS

This trial is open to accrual in the University of Maryland Medical System as of March 2024, and as of July 3, 2024, a total of 20 participants have consented.

CONCLUSIONS

This study is among the first to digitize the SCP in a mobile app and test the effects of a mobile health-delivered behavioral health intervention on symptom burden in cancer survivors. Our results will provide evidence about the effects of health self-management on symptoms. This knowledge will be integral to larger randomized controlled studies, integration with the electronic medical record, and nationwide implementation.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05499663; https://clinicaltrials.gov/ct2/show/NCT05499663.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/59222.

Feature Paper in Oral Physiology and Pathology

In the realm of life sciences, the journal 'Life' has consistently served as a beacon for groundbreaking research and scientific discovery [...].

Protective Effects of Glatiramer Acetate Against Paclitaxel-Induced Peripheral Neuropathy in Rats: A Role for Inflammatory Cytokines and Oxidative Stress

Chemotherapy-induced peripheral neuropathy (CIPN) is a major challenge for cancer patients who undergo chemotherapy with paclitaxel. Therefore, finding effective therapies for CIPN is crucial. Glatiramer acetate is used to treat multiple sclerosis that exerts neuroprotective properties in various studies. We hypothesized that glatiramer acetate could also improve the paclitaxel-induced peripheral neuropathy. We used a rat model of paclitaxel (2 mg/kg/every other day for 7 doses)-induced peripheral neuropathy. Rats were treated with either different doses of glatiramer acetate (1, 2, 4 mg/kg/day) or its vehicle for 14 days in separate groups. The mechanical and thermal sensitivity of the rats by using the Von Frey test and the Hot Plate test, respectively, were assessed during the study. The levels of oxidative stress (malondialdehyde and superoxide dismutase), inflammatory markers (TNF-α, IL-10, NF-kB), and nerve damage (H&E and S100B staining) in the sciatic nerves of the rats were also measured at the end of study. Glatiramer acetate (2 and 4 mg/kg) exerted beneficial effects on thermal and mechanical allodynia tests. It also modulated the inflammatory response by reducing TNF-α and NF-κB levels, enhancing IL-10 production, and improving the oxidative stress status by lowering malondialdehyde and increasing superoxide dismutase activity in the sciatic nerve of the rats. Furthermore, glatiramer acetate enhanced nerve conduction velocity in all treatment groups. Histological analysis revealed that glatiramer acetate (2 and 4 mg/kg) prevented paclitaxel-induced damage to the nerve structure. These results suggest that glatiramer acetate can alleviate the peripheral neuropathy induced by paclitaxel.

Pilot trial testing the effects of exercise on chemotherapy-induced peripheral neurotoxicity (CIPN) and the interoceptive brain system

Purpose

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a prevalent, dose-limiting, tough-to-treat toxicity involving numbness, tingling, and pain in the extremities with enigmatic pathophysiology. This randomized controlled pilot study explored the feasibility and preliminary efficacy of exercise during chemotherapy on CIPN and the role of the interoceptive brain system, which processes bodily sensations.

Methods

Nineteen patients (65±11 years old, 52% women; cancer type: breast, gastrointestinal, multiple myeloma) starting neurotoxic chemotherapy were randomized to 12 weeks of exercise (home-based, individually tailored, moderate intensity, progressive walking and resistance training) or active control (nutrition education). At pre-, mid-, and post-intervention, we assessed CIPN symptoms (primary clinical outcome: CIPN-20), CIPN signs (tactile sensitivity using monofilaments), and physical function (leg strength). At pre- and post-intervention, we used task-free ("resting") fMRI to assess functional connectivity in the interoceptive brain system, involving the salience and default mode networks.

Results

The study was feasible (74-89% complete data across measures) and acceptable (95% retention). We observed moderate/large beneficial effects of exercise on CIPN symptoms (CIPN-20, 0-100 scale: -7.9±5.7, effect size [ES]=-0.9 at mid-intervention; -4.8±7.3, -ES=0.5 at post-intervention), CIPN signs (ES=-1.0 and -0.1), and physical function (ES=0.4 and 0.3). Patients with worse CIPN after neurotoxic chemotherapy had lower functional connectivity within the default mode network (R2=40-60%) and higher functional connectivity within the salience network (R2=20-40%). Exercise tended to increase hypoconnectivity and decrease hyperconnectivity seen in CIPN (R2 = 12%).

Conclusion

Exercise during neurotoxic chemotherapy is feasible and may attenuate CIPN symptoms and signs, perhaps via changes in interoceptive brain circuitry. Future work should test for replication with larger samples. ClinicalTrials.gov identifier NCT03021174.

Risk factors of paclitaxel-induced peripheral neuropathy in patients with breast cancer: a prospective cohort study

Objective

Chemotherapy-induced peripheral neuropathy (CIPN) is a common and severe adverse reaction in taxane-based chemotherapy. This study aimed to analyze the risk factors of peripheral neuropathy in patients with breast cancer receiving paclitaxel chemotherapy to provide a reference for the early prevention of CIPN.

Methods

We included 350 patients with breast cancer who received chemotherapy for the first time at the Tangshan People's Hospital between August 2022 and June 2023 and were followed for at least 3 months after the end of chemotherapy. The incidence of CIPN in patients with breast cancer was calculated, and risk factors for CIPN were analyzed using logistic regression analysis.

Results

The incidence rate of CIPN was 79.1%. Multifactor logistic regression analysis indicated that age ≥45 years [odds ratio (OR)=5.119, 95% confidence interval (CI)=1.395-18.780] and ≥60 years (OR=9.366, 95% CI=1.228-71.421), history of hypertension (OR=3.475, 95% CI=1.073-11.250), cumulative dose of chemotherapy drugs >900 mg (OR=4.842, 95% CI=1.961-5.946), vitamin D deficiency (OR=6.214, 95% CI=2.308-16.729), abnormal alanine aminotransferase (OR=3.154, 95% CI=1.010-9.844), anemia before chemotherapy (OR=2.770, 95% CI=1.093-7.019), infusion duration of chemotherapy drugs >30 min (OR=3.673, 95% CI=1.414-9.539), body mass index ≥24 kg/m2 (OR=8.139, 95% CI=1.157-57.240), mild depression (OR=4.546, 95% CI=1.358-15.223), and major depression (OR=4.455, 95% CI=1.237-16.037) increased the risk of CIPN. Having a regular caregiver (OR=0.223, 95% CI=0.087-0.573), high levels of physical activity (OR=0.071, 95% CI=0.008-0.647), and strong social support (OR=0.048, 95% CI=0.003-0.682) were protective factors against CIPN.

Conclusion

Clinical attention should be paid to patients with these risk factors, and active and effective preventive measures should be taken to reduce the occurrence of CIPN and improve the quality of life.

Preliminary evaluation of novel Bodily Attention Task to assess the role of the brain in chemotherapy-induced peripheral neurotoxicity (CIPN)

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a common, sometimes dose-limiting side effect of neurotoxic chemotherapy. Treatment is limited because its pathophysiology is poorly understood. Compared to research on peripheral mechanisms, the role of the brain in CIPN is understudied and it may be important to develop better treatments. We propose a novel task that assesses brain activation associated with attention to bodily sensations (interoception), without the use of painful stimulation, to understand how CIPN symptoms may be processed in the brain. The goals of this preliminary study were to assess, 1) feasibility of the task, 2) sensitivity to changes in brain activity, and 3) suitability for assessing relationships between brain activation and CIPN severity. Eleven participants with varying types of cancer completed a brain fMRI scan and rated CIPN severity (CIPN-20) before and/or 12 weeks after starting neurotoxic chemotherapy. The Bodily Attention Task is a 7.5-min long fMRI task involving attentional focus on the left fingertips, the heart, or a flashing word "target" for visual attention (reference condition). Feasibility was confirmed, as 73% of all data collected were usable and participants reported feeling or focus during 75% of the trials. Regarding brain activity, finger attention increased activation in somatosensory regions (primary sensory cortex, insula) and sensory integration regions (precuneus, dorsolateral prefrontal cortex). Exploratory analyses suggested that brain activation may be associated with CIPN severity. A larger sample size and accounting of confounding factors is needed to test for replication and to identify brain and interoceptive biomarkers to help improve the prediction, prevention, and treatment of CIPN.

Complementary and alternative medicine in relation to chemotherapy-induced peripheral neuropathy: A narrative review

PURPOSE

To summarizes the available evidence on the effectiveness, safety, and feasibility of complementary and alternative medicine (CAM) in the management of chemotherapy-induced peripheral neuropathy (CIPN).

METHODS

We searched for systematic reviews, and meta-analyzes published up to April 2023 in the Pubmed and Web of Science databases. The latest original research on related topics was also reviewed. The search was restricted to English-language papers. Two independent reviewers performed a quality assessment of the identified literature.

RESULTS

The results of 35 systematic reviews and meta-analyzes were included in this study. Preliminary evidence suggests that CAM, including acupuncture, physical activity (PA), herbal and nutritional supplements, mind-body therapies, touch therapy, and non-invasive neuromodulation techniques, have shown tremendous potential for the prevention and treatment of CIPN. Of these, there is strong evidence supporting acupuncture, PA, and herbal medicine. However, existing clinical studies are also limited by the heterogeneity of study methods, insufficient sample size, and poor study design. Further studies are needed to validate the efficacy of CAM in patients with CIPN and to elucidate potential therapeutic mechanisms.

CONCLUSIONS

Current research has reached a preliminary conclusion suggesting the potential efficacy of certain CAMs in the management of CIPN. Future clinical trials should incorporate more robust study design protocols and larger sample sizes to enhance the validity of findings.

Dietary Composition, Meal Timing, and Cancer-Related Fatigue: Insights From the Women's Healthy Eating and Living Study

BACKGROUND

Cancer-related fatigue is difficult to treat, and dietary interventions are promising yet underused.

OBJECTIVE

We explored associations between dietary patterns and fatigue, and the effect of a dietary intervention versus control on fatigue using Women's Healthy Eating and Living study data, plus mediators and moderators of the intervention effect.

METHODS

The Women's Healthy Eating and Living study was a randomized controlled trial among early-stage breast cancer survivors. The 4-year intervention encouraged fruits, vegetables, fiber, and 15% to 20% calories from fat. Fatigue outcomes included a 9-item energy scale and a single-item tiredness question. Dietary quality was estimated using a modified Healthy Eating Index (24-hour dietary recall) and serum carotenoid concentrations. Nutrient timing was obtained from 4-day food logs.

RESULTS

Among 2914 total participants, lower body mass index was associated with less tiredness and more energy at baseline (P < .001 for both). Earlier start and end times for daily eating windows were associated with less tiredness (P = .014 and P = .027, respectively) and greater energy (P = .006 and P = .102, respectively). The intervention did not lead to improvements in fatigue on average (P > .125). However, the intervention was more effective for participants who were younger, had fewer comorbidities, and did not have radiation treatment. Mediators included increases in serum carotenoids, increases in the modified Healthy Eating Index, and weight loss/maintenance.

CONCLUSION

Diet quality and earlier eating windows were associated with less fatigue.

IMPLICATIONS FOR PRACTICE

Programs that encourage high diet quality and a morning meal and discourage nighttime eating should be tested for efficacy in reducing cancer-related fatigue in survivorship.

Effectiveness of Nonpharmacologic Interventions for Chemotherapy-Induced Peripheral Neuropathy in Patients With Breast Cancer: A Systematic Review and Network Meta-analysis

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse effect in patients with breast cancer (BC) during treatment. Patients experiencing CIPN develop neuropathic symptoms, which could lead to the modification or discontinuation of chemotherapy. Nonpharmacological interventions can be simple and safe, but evidence of their effectiveness in patients with BC experiencing CIPN is currently insufficient.

OBJECTIVE

To compare and rank the effectiveness of nonpharmacologic interventions for CIPN in patients with BC.

METHODS

We conducted a systematic search of randomized controlled trials registered from database inception until October 2022 in 7 databases. We assessed studies that met the inclusion and exclusion criteria and evaluated the risk of bias. Network meta-analysis was conducted using Stata SE 17.0 (StataCorp, College Station, Texas).

RESULTS

A total of 13 studies involving 9 nonpharmacologic interventions and comprising 571 participants were included. The results of the network meta-analysis showed that cryotherapy (standard mean difference, -1.22; 95% confidence interval, -2.26 to -0.17) exerted significant effects versus usual care. Cryotherapy (surface under the cumulative ranking area [SUCRA]: 0.74) was associated with the highest likelihood of effectively alleviating CIPN in patients with BC, followed by exercise (SUCRA: 0.62) and self-acupressure (SUCRA: 0.59).

CONCLUSIONS

Cryotherapy was the most effective nonpharmacologic intervention for alleviating CIPN in patients with BC. Large-scale studies are required to verify the present findings.

IMPLICATIONS FOR PRACTICE

This study provides evidence regarding the effectiveness of nonpharmacologic interventions for CIPN. Physicians and nurses could incorporate cryotherapy into clinical practice to alleviate CIPN in patients with BC.

Coping with and self-management of chronic painful chemotherapy-induced peripheral neuropathy: a qualitative study among cancer survivors

PURPOSE

Patients with chronic painful chemotherapy-induced peripheral neuropathy (CIPN) may experience a negative impact of CIPN on daily life. They can use various coping (i.e., dealing with symptoms and resulting impairments in general) and self-management (i.e., practical actions to reduce symptoms) strategies to live with their limitations. This paper aimed to examine experienced helpful coping and self-management strategies of patients with chronic painful CIPN.

METHODS

Semi-structured interviews were conducted with twelve patients with chronic painful CIPN. We applied a hybrid deductive-inductive coding approach. ATLAS.ti was used for coding.

RESULTS

Generated from the data were two themes and nine codes for coping and four themes and 31 codes for self-management strategies. Coping of patients often included active strategies like planning, seeking social support, and acceptance. Additionally, patients often used passive strategies such as focusing on and venting emotions and suppressing competing activities. The most common self-management strategies were mostly passive (i.e., medication, deliberate choice of shoes, resting, sitting, and consulting healthcare professionals) but also active (i.e., exercising) strategies.

CONCLUSION

Patients exhibit a great variety of coping and self-management strategies that they perceive as helpful to deal with chronic painful CIPN. However, research has shown that certain strategies are not that helpful or even come with aversive effects. More research into the effectiveness and implementation of psychosocial interventions is needed since it may help patients adopting helping strategies. In addition, healthcare professionals need to refer patients with CIPN in a timely manner to physical therapists, occupational therapists, or rehabilitation teams to reduce or prevent (further) impairments.

IMPLICATIONS FOR CANCER SURVIVORS

Patients can consult one of their healthcare providers in case of problems in dealing with their symptoms, to get proper guidance and possible referral.

Mechanisms of exercise in the treatment of lung cancer - a mini-review

Lung cancer constitutes a formidable menace to global health and well-being, as its incidence and mortality rate escalate at an alarming pace. In recent years, research has indicated that exercise has potential roles in both the prevention and treatment of lung cancer. However, the exact mechanism of the coordinating effect of exercise on lung cancer treatment is unclear, limiting the use of exercise in clinical practice. The purpose of this review is to explore the mechanisms through which exercise exerts its anticancer effects against lung cancer. This review will analyze the biological basis of exercise's anticancer effects on lung cancer, with a focus on aspects such as the tumor microenvironment, matrix regulation, apoptosis and angiogenesis. Finally, we will discuss future research directions and potential clinical applications.

Effect of Exercise on Chemotherapy-Induced Peripheral Neuropathy Among Patients Treated for Ovarian Cancer: A Secondary Analysis of a Randomized Clinical Trial

Importance

Chemotherapy-induced peripheral neuropathy (CIPN), one of the most common and severe adverse effects of chemotherapy, is associated with worse quality of life among survivors of ovarian cancer. Currently, there is no effective treatment for CIPN.

Objective

To evaluate the effect of a 6-month aerobic exercise intervention vs attention-control on CIPN among women treated for ovarian cancer in the Women's Activity and Lifestyle Study in Connecticut (WALC) to provide evidence to inform the guidelines and recommendations for prevention or treatment of CIPN.

Design, Setting, and Participants

This prespecified secondary analysis evaluated the Women's Activity and Lifestyle Study in Connecticut (WALC), a multicentered, open-label, population-based, phase 3 randomized clinical trial of an aerobic exercise intervention vs attention control for CIPN in patients who were diagnosed with ovarian cancer. Only WALC participants who received chemotherapy were included in this analysis. Participants were randomized 1:1 to either a 6-month aerobic exercise intervention or to attention control. All analyses were conducted between September 2022 and January 2023.

Interventions

The exercise intervention consisted of home-based moderate-intensity aerobic exercise facilitated by weekly telephone counseling from an American College of Sports Medicine/American Cancer Society-certified cancer exercise trainer. Attention control involved weekly health education telephone calls from a WALC staff member.

Main Outcomes and Measure

Change in CIPN was the primary outcome in this secondary analysis. This outcome was represented by CIPN severity, which was self-measured by participants at baseline and 6 months using the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity scale, with a score range of 0 to 44. A mixed-effects model was used to assess the 6-month change in CIPN between the exercise intervention and attention control arms.

Results

Of the 134 participants (all females; mean [SD] age, 57.5 [8.3] years) included in the analysis, 69 were in the exercise intervention arm and 65 were in the attention control arm. The mean (SD) time since diagnosis was 1.7 (1.0) years. The mean (SD) baseline CIPN scores were 8.1 (5.6) in the exercise intervention arm and 8.8 (7.9) in the attention control arm (P = .56). At 6 months, the self-reported CIPN score was reduced by 1.3 (95% CI, -2.3 to -0.2) points in the exercise intervention arm compared with an increase of 0.4 (95% CI, -0.8 to 1.5) points in the attention control arm. The between-group difference was -1.6 (95% CI, -3.1 to -0.2) points. The point estimate was larger among the 127 patients with CIPN symptoms at enrollment (-2.0; 95% CI, -3.6 to -0.5 points).

Conclusions and Relevance

Findings of this secondary analysis of the WALC trial indicate that a 6-month aerobic exercise intervention vs attention control significantly improved self-reported CIPN among patients who were treated for ovarian cancer. While replication of the findings in other studies is warranted, incorporating referrals to exercise programs into standard oncology care could reduce CIPN symptoms and increase quality of life in patients with ovarian cancer.

Trial Registration

ClinicalTrials.gov Identifier: NCT02107066.

CYP3A genetic variation and taxane-induced peripheral neuropathy: a systematic review, meta-analysis, and candidate gene study

Background: Taxane-induced peripheral neuropathy (TIPN) is an important cause of premature treatment cessation and dose-limitation in cancer therapy. It also reduces quality of life and survivorship in affected patients. Genetic polymorphisms in the CYP3A family have been investigated but the findings have been inconsistent and contradictory. Methods: A systematic review identified 12 pharmacogenetic studies investigating genetic variation in CYP3A4*22 and CYP3A5*3 and TIPN. In our candidate gene study, 288 eligible participants (211 taxane participants receiving docetaxel or paclitaxel, and 77 control participants receiving oxaliplatin) were successfully genotyped for CYP3A4*22 and CYP3A5*3. Genotyping data was transformed into a combined CYP3A metaboliser phenotype: Poor metabolisers, intermediate metabolisers and extensive metabolisers. Individual genotypes and combined CYP3A metaboliser phenotypes were assessed in relation to neurotoxicity, including by meta-analysis where possible. Results: In the systematic review, no significant association was found between CYP3A5*3 and TIPN in seven studies, with one study reporting a protective association. For CYP3A4*22, one study has reported an association with TIPN, while four other studies failed to show an association. Evaluation of our patient cohort showed that paclitaxel was found to be more neurotoxic than docetaxel (p < 0.001). Diabetes was also significantly associated with the development of TIPN. The candidate gene analysis showed no significant association between either SNP (CYP3A5*3 and CYP3A4*22) and the development of TIPN overall, or severe TIPN. Meta-analysis showed no association between these two variants and TIPN. Transformed into combined CYP3A metaboliser phenotypes, 30 taxane recipients were poor metabolisers, 159 were intermediate metabolisers, and 22 were extensive metabolisers. No significant association was observed between metaboliser status and case-control status. Summary: We have shown that the risk of peripheral neuropathy during taxane chemotherapy is greater in patients who have diabetes. CYP3A genotype or phenotype was not identified as a risk factor in either the candidate gene analysis or the systematic review/meta-analysis, although we cannot exclude the possibility of a minor contribution, which would require a larger sample size.

Framework to leverage physical therapists for the assessment and treatment of chemotherapy-induced peripheral neurotoxicity (CIPN)

PURPOSE

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a highly prevalent, dose-limiting, costly, and tough-to-treat adverse effect of several chemotherapy agents, presenting as sensory and motor dysfunction in the distal extremities. Due to limited effective treatments, CIPN can permanently reduce patient function, independence, and quality of life. One of the most promising interventions for CIPN is physical therapy which includes exercise, stretching, balance, and manual therapy interventions. Currently, there are no physical therapy guidelines for CIPN, thus limiting its uptake and potential effectiveness.

METHODS

Utilizing the authors' collective expertise spanning physical therapy, symptom management research, oncology, neurology, and treating patients with CIPN, we propose a comprehensive clinical workflow for physical therapists to assess and treat CIPN. This workflow is based on (1) physical therapy guidelines for treating neurologic symptoms like those of CIPN, (2) results of clinical research on physical therapy and exercise, and (3) physical therapy clinical judgement.

RESULTS

We present detailed tables of pertinent physical therapy assessment and treatment methods that can be used in clinical settings. CIPN assessment should include detailed sensory assessment, objective strength assessments of involved extremities, and validated physical performance measures incorporating static and dynamic balance, gait, and functional mobility components. CIPN treatment should involve sensorimotor, strength, balance, and endurance-focused interventions, alongside a home-based exercise prescription that includes aerobic training. We conclude with action items for oncology teams, physical therapists, patients, and researchers to best apply this framework to address CIPN.

CONCLUSIONS

Physical therapists are in a unique position to help assess, prevent, and treat CIPN given their training and prevalence, yet there are no physical therapy clinical practice guidelines for CIPN. Our preliminary suggestions for CIPN assessments and treatments can catalyze the development of guidelines to assess and treat CIPN. We urge oncology teams, physical therapists, patients, and researchers to develop, adapt, and disseminate this framework to help alleviate the burden of chemotherapy on patients with cancer.

Physical activity behaviors in cancer survivors treated with neurotoxic chemotherapy

AIM

There are many barriers to physical activity among cancer survivors. Survivors treated with neurotoxic chemotherapy may develop chemotherapy-induced peripheral neuropathy (CIPN) and experience additional barriers related to sensorimotor and mobility deficits. This study examined physical activity behaviors, including physical activity predictors, among cancer survivors treated with neurotoxic chemotherapies.

METHODS

A cross-sectional study of 252 participants, 3-24 months after neurotoxic chemotherapy, was undertaken. Physical activity was self-reported (IPAQ). CIPN was self-reported (FACT/GOG-Ntx-13), clinically graded (NCI-CTCAE), and objectively measured using neurological grading scales and neurophysiological techniques (tibial and sural nerve conduction studies). Balance (Swaymeter) and fine motor skills (grooved pegboard) were assessed. Regression models were used to identify clinical, demographic and CIPN predictors of walking and moderate-vigorous physical activity.

RESULTS

Forty-four percent of participants did not meet recommended physical activity guidelines (≥150 min/week). Sixty-six percent presented with CIPN. Nineteen percent of participants with CIPN reported that symptoms interfered with their ability to be physically active. A lower proportion of survivors aged ≥60, with grade ≥1 CIPN or BMI ≥30, reported meeting physical activity guidelines (all p < .05). Regression models identified older age, higher BMI, and patient-reported CIPN associated with lower walking, while higher BMI and females were associated with lower moderate-vigorous physical activity. Neurologically assessed CIPN did not associate with walking or moderate-vigorous physical activity.

CONCLUSION

Cancer survivors exposed to neurotoxic chemotherapy have low physical activity levels. Further work should examine the factors causing physical activity limitations in this cohort and designing interventions to improve physical function and quality of life in survivors.

Towards a mechanistic understanding of axon transport and endocytic changes underlying paclitaxel-induced peripheral neuropathy

Paclitaxel is a common chemotherapeutic agent widely used to treat solid cancer. However, it frequently causes peripheral sensory neuropathy, resulting in sensory abnormalities and pain in patients receiving treatment for cancer. As one of the most widely used chemotherapeutics, many preclinical studies on paclitaxel-induced peripheral neuropathy (PIPN) have been performed. Yet, there remain no effective options for treatment or prevention. Due to paclitaxel's ability to bind to and stabilize microtubules, a change in microtubule dynamics and subsequent disruptions in axonal transport has been predicted as a major underlying cause of paclitaxel-induced toxicity. However, the systemic understanding of PIPN mechanisms is largely incomplete, and various phenotypes have not been directly attributed to microtubule-related effects. This review aims to provide an overview of the literature involving paclitaxel-induced alteration in microtubule dynamics, axonal transport, and endocytic changes. It also aims to provide insights into how the microtubule-mediated hypothesis may relate to various phenotypes reported in PIPN studies.

Chemotherapy-induced peripheral neuropathy in children and adolescent cancer patients

Brain cancer and leukemia are the most common cancers diagnosed in the pediatric population and are often treated with lifesaving chemotherapy. However, chemotherapy causes severe adverse effects and chemotherapy-induced peripheral neuropathy (CIPN) is a major dose-limiting and debilitating side effect. CIPN can greatly impair quality of life and increases morbidity of pediatric patients with cancer, with the accompanying symptoms frequently remaining underdiagnosed. Little is known about the incidence of CIPN, its impact on the pediatric population, and the underlying pathophysiological mechanisms, as most existing information stems from studies in animal models or adult cancer patients. Herein, we aim to provide an understanding of CIPN in the pediatric population and focus on the 6 main substance groups that frequently cause CIPN, namely the vinca alkaloids (vincristine), platinum-based antineoplastics (cisplatin, carboplatin and oxaliplatin), taxanes (paclitaxel and docetaxel), epothilones (ixabepilone), proteasome inhibitors (bortezomib) and immunomodulatory drugs (thalidomide). We discuss the clinical manifestations, assessments and diagnostic tools, as well as risk factors, pathophysiological processes and current pharmacological and non-pharmacological approaches for the prevention and treatment of CIPN.

Non-Pharmacological Self-Management Strategies for Chemotherapy-Induced Peripheral Neuropathy in People with Advanced Cancer: A Systematic Review and Meta-Analysis

Non-pharmacological self-management interventions for chemotherapy-induced peripheral neurotherapy (CIPN) are of clinical interest; however, no systematic review has synthesized the evidence for their use in people with advanced cancer. Five databases were searched from inception to February 2022 for randomized controlled trials assessing the effect of non-pharmacological self-management interventions in people with advanced cancer on the incidence and severity of CIPN symptoms and related outcomes compared to any control condition. Data were pooled with meta-analysis. Quality of evidence was appraised using the Revised Cochrane Risk of Bias Tool for Randomized Trials (RoB2), with data synthesized narratively. Grading of Recommendations, Assessment, Development and Evaluations (GRADE) was applied to assess the certainty of the evidence. Thirteen studies were included, which had a high (69%) or unclear (31%) risk of bias. Greatest confidence was found for physical exercise decreasing CIPN severity (SMD: −0.89, 95% CI: −1.37 to −0.41; p = 0.0003; I² = 0%; n = 2 studies, n = 76 participants; GRADE level: moderate) and increasing physical function (SMD: 0.51, 95% CI: 0.02 to 1.00; p = 0.04; I² = 42%; n = 3 studies, n = 120; GRADE level: moderate). One study per intervention provided preliminary evidence for the positive effects of glutamine supplementation, an Omega-3 PUFA-enriched drink, and education for symptom self-management via a mobile phone game on CIPN symptoms and related outcomes (GRADE: very low). No serious adverse events were reported. The strongest evidence with the most certainty was found for physical exercise as a safe and viable adjuvant to chemotherapy treatment for the prevention and management of CIPN and related physical function in people with advanced cancer. However, the confidence in the evidence to inform conclusions was mostly very low to moderate. Future well-powered and appropriately designed interventions for clinical trials using validated outcome measures and clearly defined populations and strategies are warranted.