Exploring the reliability and validity of clinically-relevant outcome measures for chemotherapy-induced peripheral neuropathy.

PURPOSE: To explore the reliability and validity of clinically-relevant outcome measures for balance (i.e., The Short Physical Performance Battery [SPPB] - Balance Subscale) and sensation (i.e., monofilament threshold testing) for use in clinical trials of chemotherapy-induced peripheral neuropathy (CIPN). METHODS: Adult, post-treatment cancer survivors (N = 142) who had reported ≥ 4/10 CIPN symptom severity following neurotoxic chemotherapy were recruited from six National Cancer Institute Community Oncology Research Program (NCORP) sites associated with the University of Rochester Cancer Center NCORP Research Base. Participants completed the monofilament threshold test at the screening and baseline time points (i.e., one week apart), while the Quality of Life Questionnaire-CIPN20, Treatment-Induced Neuropathy Assessment Scale, and SPPB - Balance Subscale were completed at baseline. Test-retest reliability of the monofilament threshold testing scores was assessed using the Intraclass Correlation Coefficient (ICC). The convergent validity among monofilament threshold testing, SPPB - Balance Subscale, and CIPN patient-reported outcome (PRO) scores at baseline was assessed using Spearman's correlation. RESULTS: Ceiling effects were observed for SPPB-Balance Subscale scores as 113 (79.6%) respondents reported the highest score. Agreement between the screening and baseline monofilament threshold testing scores was moderate (ICC = 0.65). Monofilament threshold testing (rs Range: 0.14 - 0.21) and SPPB Balance Subscale scores (rs Range: -0.36 - -0.22) showed largely low correlations with all PRO measures. CONCLUSIONS: Monofilament threshold testing demonstrated moderate test-retest reliability, but low convergent validity with CIPN PROs, while the SPPB - Balance Subscale demonstrated low convergent validity with CIPN PROs and ceiling effects (i.e., highest possible score) among post-treatment cancer survivors with CIPN. Future research is needed to identify promising measures of balance and sensation loss for use in clinical trials that complement CIPN PROs to aid in the identification of clinically relevant treatments for CIPN. TRIAL REGISTRATION: NCT04367490 [April 29, 2020].

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.

Personalized Outcomes in Neuropathic Pain: A Clinical Relevance and Assay Sensitivity Analysis from a Randomized Controlled Trial.

OBJECTIVE: To explore the clinical relevance and assay sensitivity of using personalized outcomes using data from a randomized clinical trial (RCT) in people with chemotherapy induced peripheral neuropathy (CIPN). DESIGN: This study is a secondary analysis that leveraged data from a RCT of transcutaneous electrical stimulation for CIPN to test whether personalized outcomes could minimize potential floor effects and increase the assay sensitivity of pain clinical trials (ie, ability to detect a true treatment effect). SETTING: Participants were recruited for a RCT from community oncology clinics in the U.S. PARTICIPANTS: Adults with CIPN (N = 72) who reported on average ≥4 intensity (measured via a 7-day baseline diary) for at least one of the following pain qualities hot/burning pain, sharp/shooting pain and/or cramping. METHODS: Personalized outcomes were defined based on participants' unique presentation of pain qualities at baseline, measured via 0-10 numeric rating scales (NRS), or ranking of the distress caused by the pain qualities. Analysis of covariance models estimated the treatment effect as measured by personalized and non-personalized outcomes. RESULTS: The adjusted mean difference between groups was higher using personalized outcomes (ie, 1.21-1.25 NRS points) compared to a non-personalized outcome (ie, 0.97 NRS points), although the standardized effect sizes were similar between outcomes (0.49-0.54). CONCLUSIONS: These results suggest that personalized pain quality outcomes could minimize floor effects, while providing similar assay sensitivity to non-personalized pain quality outcomes. Personalized outcomes better reflect an individual's unique experience, inherently providing more clinically relevant estimates of treatment effects. Personalized outcomes may be advantageous particularly for clinical trials in populations with high inter-individual variability in pain qualities.

Exploring Patients' Understanding of Chemotherapy-Induced Peripheral Neuropathy.

Little quantitative evidence exists surrounding patients' level of understanding of chemotherapy-induced peripheral neuropathy (CIPN) symptoms (numbness, tingling, pain in the hands/feet) and consequences (e.g., negatively affect physical functioning or chemotherapy dosing) at the beginning of chemotherapy. The purpose of this cross-sectional, secondary analysis was to describe CIPN knowledge and education patterns among adults early in a course of neurotoxic chemotherapy for the treatment of cancer (< three infusions). Following consent, participants completed an electronic questionnaire about their perceptions of CIPN symptoms, incidence, and education. Participants (N = 92) were mainly female (76%), white (91%), and diagnosed with breast (46%) or gastrointestinal (40%) cancers. Most participants without CIPN (n = 48) did not expect to develop CIPN (45%) or were unaware of CIPN as a side-effect (30%). Furthermore, 71% of participants without CIPN (n = 31) estimated CIPN to occur in ≤ 30% of patients receiving neurotoxic chemotherapy. Overall, participants learned about CIPN from their doctor or nurse prior to beginning chemotherapy (90%). Clinicians delivered education about CIPN symptoms (75%), but less frequently delivered education about CIPN management (14%), or the impact of CIPN on the ability to continue chemotherapy (16%) or physical functioning (24%). Finally, participants reported that a discussion with their doctor/nurse would be the best way to learn about CIPN (92%). Results revealed that participants without CIPN were largely unaware of the adverse consequences or incidence of CIPN during treatment. Further research is needed to investigate optimal methods to promote patient-clinician communication about CIPN during chemotherapy to enhance patients' retention of CIPN information and activation in their care.

Identifying participants' preferences for modifiable chemotherapy-induced peripheral neuropathy prevention clinical trial factors: an adaptive choice-based conjoint analysis.

PURPOSE: There are no recommended treatments for chemotherapy-induced peripheral neuropathy (CIPN) prevention. Recruitment to CIPN prevention clinical trials is challenging because it is difficult to enroll patients between the time of cancer diagnosis and the initiation of neurotoxic chemotherapy. The purpose of this exploratory-sequential mixed-methods study was to determine patients' preferences that could affect the choice to participate in CIPN prevention clinical trials. METHODS: First, twenty cognitive interviews were conducted with adults who completed less than three neurotoxic chemotherapy infusions to clarify clinical trial attributes and levels thought to be important to patients when deciding whether to enroll in CIPN prevention trials (i.e., type of treatment, clinical tests, reimbursement, survey delivery; length of visits, timing of follow-up, when to begin treatment). Second, another eighty-eight patients completed an adaptive choice-based conjoint analysis survey that incorporated the finalized attributes and levels. Each level was assigned a part-worth utility score using Hierarchical Bayes Estimation. The relative importance of each attribute was calculated. RESULTS: The attributes with the highest relative importance values were type of treatment (27.1%) and length of study visits (20.2%). The preferred levels included non-medicine treatment (53.49%), beginning treatment after experiencing CIPN (60.47%), email surveys (63.95%), assessments that include surveys and clinical exams (39.53%), under 30-min visits (44.19%), $50/week reimbursement (39.53%), and 1-month post-chemotherapy follow-up visits (32.56%). CONCLUSIONS: Patients' preferences for participation may be included in the design of future CIPN prevention clinical trials to potentially bolster study enrollment.

Predicting Treatment Response with Sensory Phenotyping in Post-Traumatic Neuropathic Pain.

OBJECTIVE: Currently available treatments for neuropathic pain are only modestly efficacious when assessed in randomized clinical trials and work for only some patients in the clinic. Induced-pain or gain-of-function phenotypes have been shown to predict response to analgesics (vs placebos) in patients with neuropathic pain. However, the predictive value of these phenotypes has never been studied in post-traumatic neuropathic pain. METHODS: Mixed-effects models for repeated measures were used to evaluate the efficacy of pregabalin vs placebo in subgroups with induced-pain phenotypes (i.e., hyperalgesia or allodynia) in data from a recent, multinational randomized clinical trial (N = 539) that identified phenotypic subgroups through the use of a structured clinical exam. RESULTS: The difference in mean pain score between the active and placebo groups (i.e., delta) after 15 weeks of treatment for the subgroup with hyperalgesia was -0.76 (P = 0.001), compared with 0.19 (P = 0.47) for the subgroup that did not have hyperalgesia. The treatment-by-phenotype interaction, which tests whether subgroups have statistically different treatment responses, was significant (P = 0.0067). The delta for the subgroup with allodynia was -0.31 (P = 0.22), compared with -0.30 (P = 0.22) for the subgroup that did not have allodynia (treatment-by-phenotype interaction P = 0.98). CONCLUSIONS: These data suggest that hyperalgesia, but not allodynia, predicts response to pregabalin in patients with chronic post-traumatic neuropathic pain. This study extends the growing data supporting the utility of induced-pain phenotypes to predict response to analgesics in post-traumatic neuropathic pain. Sensory phenotyping in large, multisite trials through the use of a structured clinical exam has the potential to accelerate the development of new analgesics and improve the generalizability of clinical trial results.

Diagnostic criteria for idiopathic small fiber neuropathy: A systematic review.

Idiopathic small fiber neuropathy (iSFN) lacks broadly accepted diagnostic criteria, which hinders its timely diagnosis and treatment. A systematic literature review was performed to assess the published screening and diagnostic criteria for iSFN, excluding studies where SFN was of well-established etiology. Eighty-four clinical studies and seven guideline/review publications were included in this systematic review. Substantial heterogeneity existed in iSFN diagnostic criteria. The most common set of criteria to diagnose iSFN [presence of any symptoms of iSFN, absence of large fiber involvement, and reduced intraepidermal nerve fiber density (IENFD)] was used in only 14% of studies. Mandatory individual criteria to confirm iSFN included any sensory symptoms (60% of studies), pain (19% of studies), small fiber signs (20% of studies), absence of large fiber signs (62% of studies), reduced IENFD (38% of studies), and autonomic symptoms (1% of studies). This review highlights a clear need for standardized, evidence-based guidelines for diagnosing iSFN.

Chemotherapy-induced peripheral neuropathy (CIPN) and its treatment: an NIH Collaboratory study of claims data.

PURPOSE: Chemotherapy-induced peripheral neuropathy (CIPN) is a disabling complication of many chemotherapies. We investigated the feasibility of using health plan claims and administrative data to identify CIPN occurrence by comparing patients who received neurotoxic and non-neurotoxic chemotherapies. METHODS: The sample included over 53,000,000 patients from two regional and one national insurer in the USA (> 400,000 exposed to chemotherapy). Peripheral neuropathy was identified using a broad definition (definition 1) and a specific definition (i.e., drug-induced polyneuropathy code) (definition 2). RESULTS: CIPN incidence as measured by definition 1 within 6 months of chemotherapy initiation was 18.1% and 6.2% for patients who received neurotoxic and non-neurotoxic chemotherapy, respectively (relative risk neurotoxic vs. non-neurotoxic (RR), 2.93 (95% CI, 2.87-2.98)). For definition 2, these incidences were 3.6% and 0.1% (RR, 25.2 (95% CI, 22.8-27.8)). The incidences of new analgesic prescriptions for neurotoxic and non-neurotoxic groups were as follows: gabapentin, 7.1%/1.7%; pregabalin, 0.69%/0.31%; and duloxetine, 0.78%/0.76%. The incidence of CIPN as defined by definitions 1 and 2 was low compared with that of published research studies, but the relative risk of CIPN among patients who received neurotoxic chemotherapies compared with those who received non-neurotoxic chemotherapies was high using definition 2. CONCLUSIONS: These data suggest that as used currently by clinicians, administrative codes likely underestimate CIPN incidence. Thus, studies using administrative data to estimate CIPN incidence are not currently feasible. However, the drug-induced polyneuropathy code is a specific indicator of CIPN in administrative data and may be useful for investigating predictors or potentially preventive therapies of CIPN.

Utility of topical agents for radiation dermatitis and pain: a randomized clinical trial.

PURPOSE: Although topical agents are often provided during radiation therapy, there is limited consensus and evidence for their use prophylactically to prevent or reduce radiation dermatitis. METHODS: This was a multi-site, randomized, placebo-controlled, blinded study of 191 breast cancer patients to compare the prophylactic effectiveness of three topical agents (Curcumin, HPR Plus™, and Placebo) for reducing radiation dermatitis and associated pain. Patients applied the topical agent to their skin in the radiation area site three times daily starting the first day of radiation therapy (RT) until 1 week after RT completion. RESULTS: Of the 191 randomized patients, 171 patients were included in the final analyses (87.5% white females, mean age = 58 (range = 36-88)). Mean radiation dermatitis severity (RDS) scores did not significantly differ between study arms (Curcumin = 2.68 [2.49, 2.86]; HPR Plus™ = 2.64 [2.45, 2.82]; Placebo = 2.63 [2.44, 2.83]; p = 0.929). Logistic regression analyses showed that increased breast field separation positively correlated with increased radiation dermatitis severity (p = 0.018). In patients with high breast field separation (≥ 25 cm), RDS scores (Curcumin = 2.70 [2.21, 3.19]; HPR Plus™ = 3.57 [3.16, 4.00]; Placebo = 2.95 [2.60, 3.30]; p = 0.024) and pain scores (Curcumin = 0.52 [- 0.28, 1.33]; HPR Plus™ = 0.55 [- 0.19, 1.30]; Placebo = 1.73 [0.97, 2.50]; p = 0.046) significantly differed at the end of RT. CONCLUSIONS: Although there were no significant effects of the treatment groups on the overall population, our exploratory subgroup analysis suggests that prophylactic treatment with topical curcumin may be effective for minimizing skin reactions and pain for patients with high breast separation (≥ 25 cm) who may have the worst skin reactions.

Overview and critical revision of clinical assessment tools in chemotherapy-induced peripheral neurotoxicity.

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a major toxicity of cancer treatment, leading to dose reduction and premature treatment cessation, potentially affecting patient function, and quality of life. The development of accurate and sensitive assessment tools for CIPN is essential to enable clinical monitoring during treatment, follow-up of long-term outcomes and measurement of toxicity in clinical trials. This review examines CIPN clinical assessment scales incorporating clinician-based, composite, and patient-reported outcomes (PROs), providing a systematic review of their properties and an updated critical analysis of recommendations on current evidence for their use. This systematic review of CIPN assessment tools identified 50 papers containing 41 assessment tools, across 4 categories (common toxicity criteria; composite neurological scale; PROs; pain scale). The majority of these tools were PROs, underscoring the importance of patient-based assessment of symptoms. While there has been considerable work in the field over the past 10 years, this review highlights significant gaps, including a lack of evaluation of responsiveness and problematic neuropathic pain evaluation. There remains a need for consensus on the best available tool and the need to modify existing instruments to improve utility.

Wireless transcutaneous electrical nerve stimulation device for chemotherapy-induced peripheral neuropathy: an open-label feasibility study.

Chemotherapy-induced peripheral neuropathy (CIPN) occurs in approximately 68% of patients who receive neurotoxic chemotherapy and lasts at least 6 months post-chemotherapy in approximately 30% of individuals. CIPN is associated with decreased quality of life and functional impairments. Evidence suggests that CIPN symptoms are caused, in part, by enhanced excitability and impaired inhibition in the central nervous system. Transcutaneous electrical nerve stimulation (TENS) decreases pain by counteracting both of these mechanisms and is efficacious in other conditions associated with neuropathic pain. This single-arm study (n = 29) assessed the feasibility of investigating TENS for CIPN after chemotherapy completion using a wireless, home-based TENS device. Eighty-one percent of eligible patients who were approached enrolled, and 85% of participants who received the TENS device completed the primary (6-week) study term. Qualitative interview data suggest that use of the device on the continuous setting that automatically alternates between 1-h stimulation and rest periods for 5 h/day would be acceptable to most participants. Significant (i.e., p < 0.05) improvements were observed with the EORTC-CIPN20 (percent change from baseline: 13%), SF-MPQ-2 (52%), numeric rating scale of pain (38%), tingling (30%), numbness (20%), and cramping (53%), and UENS large fiber sensation subscore (48%). Preliminary data that support the reliability and construct validity of the UENS for CIPN in cancer survivors are also provided. Together these data suggest that it is feasible to evaluate TENS for CIPN using a wireless, home-based device and that further evaluation of TENS for CIPN in a randomized clinical trial is warranted.

Oral curcumin for radiation dermatitis: a URCC NCORP study of 686 breast cancer patients.

PURPOSE: Despite advances in medical technology, radiation dermatitis occurs in 95% of patients receiving radiation therapy (RT) for cancer. Currently, there is no standard and effective treatment for the prevention or control of radiation dermatitis. The goal of the study was to determine the efficacy of oral curcumin, one of the biologically active components in turmeric, at reducing radiation dermatitis severity (RDS) at the end of RT, using the RDS scale, compared to placebo. METHODS: This was a multisite, randomized, double-blinded, placebo-controlled trial of 686 breast cancer patients. Patients took four 500-mg capsules of placebo or curcumin three times daily throughout their prescribed course of RT until 1 week post-RT. RESULTS: A total of 686 patients were included in the final analyses (87.5% white females, mean age = 58). Linear mixed-model analyses demonstrated that curcumin did not reduce radiation dermatitis severity at the end of RT compared to placebo (B (95% CI) = 0.044 (- 0.101, 0.188), p = 0.552). Fewer curcumin patients with RDS > 3.0 suggested a trend toward reduced severity (7.4 vs. 12.9%, p = 0.082). Patient-reported changes in pain, symptoms, and quality of life were not statistically significant between arms. CONCLUSIONS: Oral curcumin did not significantly reduce radiation dermatitis severity compared to placebo. The skin rating variation and broad eligibility criteria could not account for the undetectable therapeutic effect. An objective measure for radiation dermatitis severity and further exploration for an effective treatment for radiation dermatitis is warranted.

Effects of exercise during chemotherapy on chemotherapy-induced peripheral neuropathy: a multicenter, randomized controlled trial.

PURPOSE: Over half of all cancer patients receiving taxane-, platinum-, or vinca alkaloid-based chemotherapy experience chemotherapy-induced peripheral neuropathy (CIPN), which includes numbness, tingling, pain, cold sensitivity, and motor impairment in the hands and feet. CIPN is a dose-limiting toxicity, potentially increasing mortality. There are no FDA-approved drugs to treat CIPN, and behavioral interventions such as exercise are promising yet understudied. This secondary analysis of our nationwide phase III randomized controlled trial of exercise for fatigue examines (1) effects of exercise on CIPN symptoms, (2) factors that predict CIPN symptoms, and (3) factors that moderate effects of exercise on CIPN symptoms. METHODS: Cancer patients (N = 355, 56 ± 11 years, 93% female, 79% breast cancer) receiving taxane-, platinum-, or vinca alkaloid-based chemotherapy were randomized to chemotherapy or chemotherapy plus Exercise for Cancer Patients (EXCAP©®). EXCAP is a standardized, individualized, moderate-intensity, home-based, six-week progressive walking and resistance exercise program. Patients reported CIPN symptoms of numbness and tingling and hot/coldness in hands/feet (0-10 scales) pre- and post-intervention. We explored baseline neuropathy, sex, age, body mass index, cancer stage, and cancer type as possible factors associated with CIPN symptoms and exercise effectiveness. RESULTS: Exercise reduced CIPN symptoms of hot/coldness in hands/feet (-0.46 units, p = 0.045) and numbness and tingling (- 0.42 units, p = 0.061) compared to the control. Exercise reduced CIPN symptoms more for patients who were older (p = 0.086), male (p = 0.028), or had breast cancer (p = 0.076). CONCLUSIONS: Exercise appears to reduce CIPN symptoms in patients receiving taxane-, platinum-, or vinca alkaloid-based chemotherapy. Clinicians should consider prescribing exercise for these patients. TRIAL REGISTRATION: Clinical Trials.gov , # NCT00924651, http://www.clinicaltrials.gov .

Content validity of symptom-based measures for diabetic, chemotherapy, and HIV peripheral neuropathy.

INTRODUCTION: No treatments for axonal peripheral neuropathy are approved by the United States Food and Drug Administration (FDA). Although patient- and clinician-reported outcomes are central to evaluating neuropathy symptoms, they can be difficult to assess accurately. The inability to identify efficacious treatments for peripheral neuropathies could be due to invalid or inadequate outcome measures. METHODS: This systematic review examined the content validity of symptom-based measures of diabetic peripheral neuropathy, HIV neuropathy, and chemotherapy-induced peripheral neuropathy. RESULTS: Use of all FDA-recommended methods to establish content validity was only reported for 2 of 18 measures. Multiple sensory and motor symptoms were included in measures for all 3 conditions; these included numbness, tingling, pain, allodynia, difficulty walking, and cramping. Autonomic symptoms were less frequently included. CONCLUSIONS: Given significant overlap in symptoms between neuropathy etiologies, a measure with content validity for multiple neuropathies with supplemental disease-specific modules could be of great value in the development of disease-modifying treatments for peripheral neuropathies. Muscle Nerve 55: 366-372, 2017.

The effect of YOCAS©® yoga for musculoskeletal symptoms among breast cancer survivors on hormonal therapy.

Up to 50% of breast cancer survivors on aromatase inhibitor therapy report musculoskeletal symptoms such as joint and muscle pain, significantly impacting treatment adherence and discontinuation rates. We conducted a secondary data analysis of a nationwide, multi-site, phase II/III randomized, controlled, clinical trial examining the efficacy of yoga for improving musculoskeletal symptoms among breast cancer survivors currently receiving hormone therapy (aromatase inhibitors [AI] or tamoxifen [TAM]). Breast cancer survivors currently receiving AI (N = 95) or TAM (N = 72) with no participation in yoga during the previous 3 months were randomized into 2 arms: (1) standard care monitoring and (2) standard care plus the 4-week yoga intervention (2x/week; 75 min/session) and included in this analysis. The yoga intervention utilized the UR Yoga for Cancer Survivors (YOCAS©(®)) program consisting of breathing exercises, 18 gentle Hatha and restorative yoga postures, and meditation. Musculoskeletal symptoms were assessed pre- and post-intervention. At baseline, AI users reported higher levels of general pain, muscle aches, and total physical discomfort than TAM users (all P ≤ 0.05). Among all breast cancer survivors on hormonal therapy, participants in the yoga group demonstrated greater reductions in musculoskeletal symptoms such as general pain, muscle aches and total physical discomfort from pre- to post-intervention than the control group (all P ≤ 0.05). The severity of musculoskeletal symptoms was higher for AI users compared to TAM users. Among breast cancer survivors on hormone therapy, the brief community-based YOCAS©® intervention significantly reduced general pain, muscle aches, and physical discomfort.

Interpretation of urine drug testing results in patients using transdermal buprenorphine preparations for the treatment of chronic noncancer pain.

OBJECTIVE: To determine whether the prevailing liquid chromatography and tandem mass spectroscopy assay (LC-MS/MS) assay designed to monitor buprenorphine compliance of the sublingual formulation used in the substance abuse treatment setting can be extrapolated to the transdermal formulation used in the chronic pain treatment setting, which is 1000-fold less concentrated. DESIGN: Retrospective chart review. SUBJECTS: Self-reported compliant patients using the transdermal or sublingual formulations of buprenorhphine. Transdermal patch application was also visually confirmed during clinic visits. METHODS: Urine drug test results from a LC-MS/MS were compared between samples from transdermal and sublingual patients. RESULTS: While all sublingual patients tested positive for at least one metabolite of buprenorphine, only 69% of the transdermal patients did so. In addition, the most abundant metabolite in the transdermal patients was buprenorphine-glucuronide, as compared with norbuprenorphine-glucuronide in sublingual patients. CONCLUSIONS: These data suggest that currently available urine drug tests for buprenorphine, including the more expensive LC-MS/MS based assays, may not be sufficiently sensitive to detect the metabolites from transdermal buprenorphine patients. This study highlights the need to evaluate the value and sensitivity of urine drug tests given the wide range of buprenorphine dosing in clinical practice. These results underscore the need for additional cost benefit analyses comparing different confirmatory drug testing techniques including many commercially available drug testing options. © 2014 Wiley Periodicals, Inc.

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.

Exploring Analgesic Use Patterns Among Cancer Survivors With Chronic Chemotherapy-Induced Peripheral Neuropathy.

OBJECTIVES: To explore cancer survivors' historical and current use of analgesics for chronic chemotherapy-induced peripheral neuropathy (CIPN). SAMPLE & SETTING: 142 post-treatment cancer survivors who received neurotoxic chemotherapy and were experiencing moderate to severe CIPN. METHODS & VARIABLES: Participants completed the Treatment-Induced Neuropathy Assessment Scale at baseline and reported all analgesics used to manage CIPN. Frequency of historical or current prescription analgesic use for chronic CIPN was described and stratified by CIPN pain severity. RESULTS: At baseline, 31% of participants reported historical use of analgesics for CIPN and 46% of participants were currently using analgesics for CIPN. Gabapentin was the most frequently used analgesic, historically (20%) and currently (34%), and duloxetine was used less frequently (6% historical use, 10% current use). Many participants with severe pain (59%) reported using analgesics for CIPN. IMPLICATIONS FOR NURSING: Duloxetine, the first-line treatment for chronic CIPN pain, was used less frequently than gabapentin, a common prescription analgesic for neuropathic pain. Further research is needed to determine strategies to promote the implementation of evidence-based CIPN treatments in clinical practice.