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

A Delphi Study on the Management of Neuropathic Cancer Pain in Spain: The DOLNEO Study

Purpose

The objectives of this project were to assess the current situation and management of cancer-related neuropathic pain (CRNP) in Spain and to provide specific recommendations for the assessment, diagnosis and treatment of CRNP using a Delphi methodology.

Methods

This was a qualitative study that followed a Delphi methodology using a questionnaire with 56 statements that were grouped into 5 areas related to CRNP: prevalence and impact, pathophysiology, assessment and diagnosis, specific syndromes, treatment, and multidisciplinary approach. Based on the responses, the scientific committee prepared an algorithm and a recommended pathway for the management of CRNP.

Results

Seventy-nine physicians attended the meeting and completed the questionnaire. Consensus was reached for all statements relating to the prevalence and impact of CRNP. However, the perceptions of specialists from palliative care of the frequency and impact of CRNP differed from those of other specialists. A high degree of consensus was reached for all statements concerning the assessment and diagnosis of CRNP. Regarding specific syndromes, the only statement with a lack of consensus was that on the frequency of NP in patients undergoing radiotherapy. There were some disagreements regarding the multidisciplinary approach and referral criteria for the management of NP.

Conclusion

Our results show a large degree of agreement on the assessment, diagnosis and treatment of cancer-related neuropathic pain among the specialists involved in its management. There were, however, some disagreements regarding the multidisciplinary approach and referral criteria for the management of neuropathic pain.

Dietary Supplements in Chemotherapy-Induced Peripheral Neuropathy: A New Hope?

Chemotherapy-induced peripheral neuropathy (CIPN) is one of the main and most prevalent side effects of chemotherapy, significantly affecting the quality of life of patients and the course of chemotherapeutic treatment. Nevertheless, despite its prevalence, the management of the CIPN is considered particularly challenging, with this condition often being perceived as very difficult or even impossible to prevent with currently available agents. Therefore, it is imperative to find better options for patients diagnosed with this condition. While the search for the new agents must continue, another opportunity should be taken into consideration—repurposing of the already known medications. As proposed, acetyl-L-carnitine, vitamins (group B and E), extracts of medical plants, including goshajinkigan, curcumin and others, unsaturated fatty acids, as well as the diet composed of so-called “sirtuin-activating foods”, could change the typical way of treatment of CIPN, improve the quality of life of patients and maintain the continuity of chemotherapy. This review summarizes currently available data regarding mentioned above agents and evaluates the rationale behind future research focused on their efficacy in CIPN.

An Overview on Chemotherapy-induced Cognitive Impairment and Potential Role of Antidepressants

BACKGROUND

Cognitive impairment is an adverse reaction of cancer chemotherapy and is likely to affect up to 75% of patients during the treatment and 35% of patients experience it for several months after the chemotherapy. Patients manifest symptoms like alteration in working ability, awareness, concentration, visual-verbal memory, attention, executive functions, processing speed, fatigue and behavioural dysfunctions. Post-chemotherapy, cancer survivors have a reduced quality of life due to the symptoms of chemobrain. Apart from this, there are clinical reports which also associate mood disorders, vascular complications, and seizures in some cases. Therefore, the quality of lifestyle of cancer patients/ survivors is severely affected and only worsens due to the absence of any efficacious treatments. With the increase in survivorship, it's vital to identify effective strategies, until then only symptomatic relief for chemobrain can be provided. The depressive symptoms were causally linked to the pathophysiological imbalance between the pro and antiinflammatory cytokines.

CONCLUSION

The common causative factor, cytokines can be targeted for the amelioration of an associated symptom of both depression and chemotherapy. Thus, antidepressants can have a beneficial effect on chemotherapy-induced inflammation and cognitive dysfunction via cytokine balance. Also, neurogenesis property of certain antidepressant drugs rationalises their evaluation against CICI. This review briefly glances upon chemotherapy-induced cognitive impairment (CICI), and the modulatory effect of antidepressants on CICI pathomechanisms.

Non-opioid Analgesics and Emerging Therapies

Pain is a common and debilitating symptom of cancer. Cancer-related pain can occur at any point along the continuum from diagnosis to treatment to survivorship¹. A systematic review published in 2016 estimated the prevalence of cancer pain to be 55% in those undergoing antineoplastic treatment, 66.4% in advanced cancer, and 39.3% in the post-treatment population. Thirty-eight percent of cancer patients in this pooled analysis experienced moderate to severe pain².

Characterizing patient-clinician chemotherapy-induced peripheral neuropathy assessment and management communication approaches

OBJECTIVE

To describe the frequency and characteristics of chemotherapy-induced peripheral neuropathy (CIPN) assessment and management communication approaches between patients receiving neurotoxic chemotherapy and clinicians.

METHODS

The data used in this analysis originated from a randomized controlled trial in which adults with cancer self-reported treatment-related symptoms using web-based symptom assessment technology. Three-to-six weeks after study initiation, each participant's outpatient visit was audio-recorded. Audio recordings and associated clinician notes for 159 participants who received platinum and/or taxane-based chemotherapy were coded for the presence of several CIPN assessment and management communication characteristics.

RESULTS

Participants received low cumulative neurotoxic chemotherapy doses (75%) at the time of audio recording. CIPN was discussed and documented in 44% and 46% of participant-clinician encounters. In symptomatic participants, clinicians asked an average of 0.7 open-ended questions, appropriately managed 70% of cases, and asked upper and lower extremity CIPN questions in 25% of cases.

CONCLUSIONS

Clinicians infrequently discussed and documented CIPN in participants with low CIPN severity, however appropriately managed mild CIPN. Development of interventions to translate existing recommended CIPN communication approaches into practice are required.

PRACTICE IMPLICATIONS

Effective participant-clinician communication is required at each clinic visit during chemotherapy treatment to identify initial signs of CIPN and offer appropriate treatment.

A Systematic Review of NMDA Receptor Antagonists for Treatment of Neuropathic Pain in Clinical Practice

OBJECTIVE

To investigate the efficacy of N-methyl-D-aspartate receptor (NMDAR) antagonists for neuropathic pain (NeuP) and review literature to determine if specific pharmacologic agents provide adequate NeuP relief.

METHODS

Literature was reviewed on PubMed using a variety of key words for 8 NMDAR antagonists. These key words include: "Ketamine and Neuropathy," "Ketamine and Neuropathic Pain," "Methadone and Neuropathy," "Methadone and Neuropathic Pain," "Memantine and Neuropathic pain," "Memantine and Neuropathy," "Amantadine and Neuropathic Pain," "Amantadine and Neuropathy," "Dextromethorphan and Neuropathic Pain," "Dextromethorphan and Neuropathy," "Carbamazepine and Neuropathic Pain," "Carbamazepine and Neuropathy," "Valproic Acid and Neuropathy," "Valproic Acid and Neuropathic Pain," "Phenytoin and Neuropathy," and "Phenytoin and Neuropathic Pain." With the results, the papers were reviewed using the PRISMA (Preferred Reporting in Systematic and Meta-Analyses) guideline.

RESULTS

A total of 58 randomized controlled trials were reviewed among 8 pharmacologic agents, which are organized by date and alphabetical order. Of the trials for ketamine, 15 showed some benefit for analgesia. Methadone had 3 positive trials, while amantadine and memantine each only had 2 trials showing NeuP analgesic properties. Dextromethorphan and valproic acid both had 4 randomized controlled trials that showed some NeuP treatment benefit while carbamazepine had over 8 trials showing efficacy. Finally, phenytoin only had 1 trial that showed clinical response in treatment.

CONCLUSIONS

There are a variety of NMDAR antagonist agents that should be considered for treatment of NeuP. Nevertheless, continued and further investigation of the 8 pharmacologic agents is needed to continue to evaluate their efficacy for treatment of NeuP.

Neuropathic Pain in Pediatric Oncology: A Clinical Decision Algorithm

Neuropathic pain in pediatric oncology can be caused by distinct lesions or disease processes affecting the somatosensory system, including chemotherapy-related neuronal injury, solid tumor-related involvement of neural structures, post-surgical neuropathic pain-including phantom limb pain and pain after limb-sparing surgery-and the complex circumstances of neuropathic pain at the end of life. Treatment algorithms reflect the general treatment principles applied for adult neuropathic pain, but the dose regimens applied in children are modest and rarely escalated to the maximum doses to optimize analgesic efficacy. Pharmacological management of neuropathic pain should be based on a stepwise intervention strategy, as combinations of medications are the most effective approach. Gabapentinoids and tricyclic antidepressants are recommended as first-line therapy. Methadone, ketamine, and lidocaine may be useful adjuvants in selected patients. Prospective studies extended over a substantial length of time are recommended because of the nature of neuropathic pain as persistent, chronic pain and based on the need for sufficient time to escalate medication dose regimens to full analgesic efficacy.

Risk of incident claims for chemotherapy-induced peripheral neuropathy among women with breast cancer in a Medicare population

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a common and disabling consequence of neurotoxic therapies, yet factors that modulate the development and clinical impact of CIPN are poorly understood. This epidemiological analysis identifies risk factors for the incidence of CIPN.

METHODS

This retrospective analysis of Surveillance, Epidemiology, and End Results-Medicare data examined predictors of incident CIPN claims among 11,149 women aged 66 years or older with American Joint Commission on Cancer (AJCC) stage II to IV breast cancer (and no secondary cancer diagnosis or preexisting neuropathy) who received chemotherapy.

RESULTS

Overall, new CIPN claims occurred for 8.3% of patients within 1 year of starting chemotherapy. Risk emerged approximately 3 months after the start of chemotherapy and increased throughout 1 year. Paclitaxel as part of first-line therapy increased CIPN risk 2.7-fold in comparison with nonneurotoxic agents (15.9% vs 5.0%), with lower incidence rates for carboplatin and paclitaxel (11.9%), carboplatin and docetaxel (9.3%), carboplatin alone (7.7%), and docetaxel alone (6.6%). The CIPN incidence rate was higher for women who at the time of their breast cancer diagnosis were relatively young (within this Medicare sample), were at AJCC stage II or III, were married or had an equivalent status, and had fewer comorbidities, but it did not differ by race/ethnicity or poverty level.

CONCLUSIONS

These Medicare claims database findings indicate that women aged 66 years or older with breast cancer are susceptible to CIPN from taxane and/or platinum compounds, with risk emerging approximately 3 months into treatment. Prospective studies of symptom emergence and clinical response (eg, stopping chemotherapy and adjunctive treatments) are indicated to determine how best to inform patients of this risk and to manage CIPN in this population.

A Systematic Review: Mindfulness Intervention for Cancer-Related Pain

Moderate-to-severe pain is a common problem experienced by patients with cancer. Although analgesic drugs are effective, adverse side effects are common and some analgesic drugs are addictive. Nonpharmacological treatment may be a way to treat cancer pain without causing negative side effects. Mindfulness is used as an effective nonpharmacological treatment to improve quality of life (QoL) and to address psychological problems including distress, anxiety, stress, and depression. However, the effect of mindfulness on pain severity has not been sufficiently investigated. Therefore, a systematic review was undertaken to describe the effectiveness of mindfulness interventions for pain and its underlying pathophysiologic mechanisms. The search was conducted in PubMed, Ovid MEDLINE, and CINAHL and included only empirical studies published from 2008 to 2017. Search terms included mindfulness, mindfulness-based intervention, meditation, cancer, pain, and cancer-related pain. Six studies met the search criteria. These studies tested several types of intervention including mindfulness-based stress reduction, mindfulness-based cognitive therapy, meditation with massage, and mindful awareness practices. Study outcomes include improved pain severity, anxiety, stress, depression, and QoL. However, most studies reviewed were conducted in the United States and Denmark. Further research is needed to test culturally appropriate mindfulness interventions to reduce pain.

Podiatric Adverse Events and Foot Care in Cancer Patients and Survivors Awareness, Education, and Literature Review

Cancer is one of the leading causes of mortality and morbidity worldwide. Recent improved therapies have resulted in more patients surviving cancer and living longer. Despite these advances, the majority of patients will develop adverse events from anticancer therapies. Foot alterations, including nail toxicities, hand-foot syndrome, edema, xerosis, hyperkeratosis, and neuropathy, are frequent among cancer patients. These untoward conditions may negatively impact quality of life, and in some cases may result in the interruption or discontinuation of cancer treatments. Appropriate prevention, diagnosis, and management of podiatric adverse events are essential to maintain foot function and health-related quality of life, both of which are critical for the care of cancer patients and survivors. This article shows results related to complaint and impact on quality of life of the Oncology Foot Care program and reviews publications specific to podiatric adverse events related to cancer treatments.

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.

Palliative care with cervical intrathecal infusion and external pump for a late-stage cancer patient with refractory pain: A case report

RATIONALE

Intrathecal therapy, with a low complication rate, has become an alternative to standard pain management for treatment of neuropathic cancer pain.

PATIENT CONCERNS

Here, we reported a late-stage cancer patient with intractable neuropathic pain in his right neck, shoulder, and upper limb.

DIAGNOSES

The pain started 2 years ago when the patient was diagnosed as squamous cell carcinoma with metastasis to right supraclavicular lymph nodes.

INTERVENTIONS

Cervical intrathecal infusion of morphine and bupivacaine with patient control analgesia by external pump was performed. The intrathecal catheter was located at the level of C6 vertebra. The initial concentration of bupivacaine and morphine were both 1 mg/mL with infusion rate of 0.3 mL/h and bolus of 0.3 mL. Subsequently, the concentrations increased to 2 mg/mL (bupivacaine) and 1.33 mg/mL (morphine), with infusion rate to 0.6 mL/h and bolus to 0.5 ml.

OUTCOMES

The pain intensity decreased from numerical rating scale 6 to 7 to 2 to 3 at rest, and from 10 to 5 to 6 of breakthrough pain.

LESSONS

In conclusion, cervical intrathecal infusion requires low concentration but high doses of bupivacaine and morphine, which is safe and effective in cancer patients with refractory pain and short life expectancy.

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.

Interleukin-6: an emerging regulator of pathological pain

Interleukin-6 is an inflammatory cytokine with wide-ranging biological effects. It has been widely demonstrated that neuroinflammation plays a critical role in the development of pathological pain. Recently, various pathological pain models have shown elevated expression levels of interleukin-6 and its receptor in the spinal cord and dorsal root ganglia. Additionally, the administration of interleukin-6 could cause mechanical allodynia and thermal hyperalgesia, and an intrathecal injection of anti-interleukin-6 neutralizing antibody alleviated these pain-related behaviors. These studies indicated a pivotal role of interleukin-6 in pathological pain. In this review, we summarize the recent progress in understanding the roles and mechanisms of interleukin-6 in mediating pathological pain associated with bone cancer, peripheral nerve injury, spinal cord injury, chemotherapy-induced peripheral neuropathy, complete Freund’s adjuvant injection, and carrageenan injection. Understanding and regulating interleukin-6 could be an interesting lead to novel therapeutic strategies for pathological pain.

Effect of Preoperative Oral Amantadine on Acute and Chronic Postoperative Pain After Mandibular Fracture Surgery

BACKGROUND

Postoperative pain from open reduction and internal fixation of mandibular fracture is a serious issue. Amantadine is an N-methyl-D-aspartic acid or N-methyl-D-aspartate (NMDA) receptor antagonist that can be effective against postoperative pain.

OBJECTIVES

The present study examined the efficacy of amantadine in alleviating the postoperative pain of mandibular fracture surgery.

PATIENTS AND METHODS

In this double-blind study, 60 patients (ASA physical status I-II) were randomly divided into two groups. The mean ages of the participants were 31.2 ± 13.1 years and 32.3 ± 18.1 years, respectively. The male/female ratios were 24/6 and 26/4, respectively, in the case and control groups. Randomization was based on a single sequence of random assignments using computer-generated random numbers. Group I was given oral amantadine 100 mg 1 hour before surgery, and group II received a placebo at the identical time. Through PCA pumps, patients received a bolus dose of morphine at 0.02 mg/kg body weight, to a maximum of 1.5 mg. PCA pumps were set at 6 minutes lockout intervals and a maximum dose of 0.15 mg/kg/h, to a maximum of 10 mg/h. Pain was assessed using a visual analog scale (VAS) at 0, 2, 4, 6, 12, and 24 hours and 1, 2, 3, 4, 5, and 6 months after surgery. The amounts of analgesic consumed were recorded for the first 24 hours, and for 6 months after surgery.

RESULTS

There were no significant differences between the two groups with respect to age, gender, nausea and vomiting, sleep quality, blood pressure, and heart rate. No significant differences were observed between the two groups in pain scores (P = 0.39) and analgesic consumption (P = 0.78).

CONCLUSIONS

The results suggest that a single dose of preoperative oral amantadine did not reduce acute or chronic postoperative pain, nor analgesic consumption.

Peripheral Nerve Field Stimulation (PNFS) as a Treatment Option for Intractable Radiation-Induced Facial Neuropathic Pain in a Survivor of Laryngeal Cancer: A Case Report

BACKGROUND

Treatment-related chronic neuropathic pain represents a major and increasing cause of discomfort in cancer survivors. Unfortunately, in approximately 10%-15% of cases, pain is scarcely relieved by opioids and common painkillers. Thus, alternative measures to manage pain have recently been adopted in these patients.

CASE DESCRIPTION

We report the case of a laryngeal cancer survivor who developed an intractable bilateral mandibular radiation-induced neuropathic pain syndrome. His pain was refractory to any pharmacological treatment, whereas the implant of bilateral subcutaneous facial electrodes led to the complete resolution of pain.

CONCLUSIONS

To the best of our knowledge, this is the first report in literature describing peripheral nerve field stimulation as a treatment option for intractable cancer treatment-related chronic neuropathic pain. Peripheral nerve field stimulation appears to be a safe and effective procedure.

Chronic Pain and Cognitive Behavioral Therapy

Cognitive behavioral therapy (CBT) is often used to treat chronic pain; however, more information is needed about what are the most efficacious dose and delivery methods. The aims of this review were to determine (a) which CBT doses, delivery methods, strategies, and follow-up periods have been explored in recent intervention studies of individuals with chronic pain and (b) whether the outcomes described in the selected studies were consistent with recommendations by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials. The CINAHL, EMBASE, PubMed, PsycInfo, and SCOPUS databases were searched for randomized controlled trials published from 2009 to 2015 testing CBT for adults with chronic pain. Thirty-five studies were included in this review. Results revealed that CBT reduced pain intensity in 43% of trials, the efficacy of online and in-person formats were comparable, and military veterans and individuals with cancer-related chronic pain were understudied.