A trial to assess the efficacy of glutamic acid in prevention of vincristine-induced neurotoxicity in pediatric malignancies: a pilot study

Genomic variations associated with risk and protection against vincristine-induced peripheral neuropathy in pediatric cancer patients

Vincristine-induced peripheral neuropathy is a common and highly debilitating toxicity from vincristine treatment that affects quality of life and often requires dose reduction, potentially affecting survival. Although previous studies demonstrated genetic factors are associated with vincristine neuropathy risk, the clinical relevance of most identified variants is limited by small sample sizes and unclear clinical phenotypes. A genome-wide association study was conducted in 1100 cases and controls matched by vincristine dose and genetic ancestry, uncovering a statistically significant (p < 5.0 × 10-8) variant in MCM3AP gene that substantially increases the risk of neuropathy and 12 variants protective against neuropathy within/near SPDYA, METTL8, PDE4D, FBN2, ZFAND3, NFIB, PAPPA, LRRTM3, NRG3, VTI1A, ARHGAP5, and ACTN1. A follow-up pathway analysis reveals the involvement of four key pathways, including nerve structure and development, myelination, neuronal transmission, and cytoskeleton/microfibril function pathways. These findings present potential actionable genomic markers of vincristine neuropathy and offer opportunities for tailored interventions to improve vincristine safety in children with cancer. This study is registered with ClinicalTrials.gov under the title National Active Surveillance Network and Pharmacogenomics of Adverse Drug Reactions in Children (ID NCT00414115, registered on December 21, 2006).

Pre-treatment amino acids and risk of paclitaxel-induced peripheral neuropathy in SWOG S0221

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a treatment-limiting and debilitating neurotoxicity of many commonly used anti-cancer agents, including paclitaxel. The objective of this study was to confirm the previously found inverse association between pre-treatment blood concentrations of histidine and CIPN occurrence and examine relationships of other amino acids with CIPN severity.

METHODS

Pre-treatment serum concentrations of 20 amino acids were measured in the SWOG S0221 (NCT00070564) trial of patients with early-stage breast cancer receiving paclitaxel. The associations between amino acids and CIPN severity were tested in regression analysis adjusted for paclitaxel schedule, age, self-reported race, and body mass index with Bonferroni correction. The network of metabolic pathways of amino acids was analyzed using over-representation analysis. The partial correlation network of amino acids was evaluated using a debiased sparse partial correlation algorithm.

RESULTS

In the primary analysis, histidine concentration was not associated with CIPN occurrence (odds ratio (OR) = 0.97 [0.83, 1.13], p = 0.72). In secondary analyses, higher concentrations of four amino acids, glutamate (β = 0.58 [0.23, 0.93], p = 0.001), phenylalanine (β = 0.54 [0.19, 0.89], p = 0.002), tyrosine (β = 0.57 [0.23, 0.91], p = 0.001), and valine (β = 0.58 [0.24, 0.92], p = 0.001) were associated with more severe CIPN, but none of these associations retained significance after adjustment. In the over-representation analysis, no amino acid metabolic pathways were significantly enriched (all FDR > 0.05). In the network of enriched pathways, glutamate metabolism had the highest centrality.

CONCLUSIONS

This analysis showed that pre-treatment serum amino acid concentrations are not strongly predictive of CIPN severity. Prospectively designed studies that assess non-amino acid metabolomics predictors are encouraged.

Applications of Cannabinoids in Neuropathic Pain: An Updated Review

Neuropathic pain is experienced due to injury to the nerves, underlying disease conditions or toxicity induced by chemotherapeutics. Multiple factors can contribute to neuropathic pain such as central nervous system (CNS)-related autoimmune and metabolic disorders, nerve injury, multiple sclerosis and diabetes. Hence, development of pharmacological interventions to reduce the drawbacks of existing chemotherapeutics and counter neuropathic pain is an urgent unmet clinical need. Cannabinoid treatment has been reported to be beneficial for several disease conditions including neuropathic pain. Cannabinoids act by inhibiting the release of neurotransmitters from presynaptic nerve endings, modulating the excitation of postsynaptic neurons, activating descending inhibitory pain pathways, reducing neural inflammation and oxidative stress and also correcting autophagy defects. This review provides insights on the various preclinical and clinical therapeutic applications of cannabidiol (CBD), cannabigerol (CBG), and cannabinol (CBN) in various diseases and the ongoing clinical trials for the treatment of chronic and acute pain with cannabinoids. Pharmacological and genetic experimental strategies have well demonstrated the potential neuroprotective effects of cannabinoids and also elaborated their mechanism of action for the therapy of neuropathic pain.

Pre-treatment Amino Acids and Risk of Paclitaxel-induced Peripheral Neuropathy in SWOG S0221

Background

Chemotherapy-induced peripheral neuropathy (CIPN) is a treatment-limiting and debilitating neurotoxicity of many commonly used anti-cancer agents, including paclitaxel. The objective of this study was to confirm the previously found inverse association between pre-treatment blood concentrations of histidine and CIPN occurrence and examine relationships of other amino acids with CIPN severity.

Methods

Pre-treatment levels of 20 amino acid concentrations were measured via a targeted mass spectrometry assay in banked serum from the SWOG S0221 (NCT00070564) trial of patients with early-stage breast cancer receiving paclitaxel. The associations between amino acid levels and CIPN occurrence or severity were tested in regression analysis adjusted for paclitaxel schedule, age, self-reported race, and body mass index with Bonferroni correction for multiple comparisons. The network of metabolic pathways of amino acids was analyzed using over-representation analysis in MetaboAnalyst. The partial correlation network of amino acids was evaluated using a debiased sparse partial correlation algorithm and Cytoscape.

Results

In the primary analysis, histidine concentration was not associated with CIPN occurrence (odds ratio (OR) = 0.97 [0.83, 1.13], p = 0.72). In a secondary analysis, no amino acid was associated with CIPN occurrence (all p > 0.0025). Higher concentrations of four amino acids, glutamate (β = 0.58 [0.23, 0.93], p = 0.001), phenylalanine (β = 0.54 [0.19, 0.89], p = 0.002), tyrosine (β = 0.57 [0.23, 0.91], p = 0.001), and valine (β = 0.58 [0.24, 0.92], p = 0.001) were associated with more severe CIPN, but none of these associations retained significance after adjustment. In the over-representation analysis, no amino acid metabolic pathways were significantly enriched (all FDR > 0.05). In the network of enriched pathways, glutamate metabolism had the highest centrality.

Conclusions

This analysis showed that pre-treatment serum amino acid concentrations are not strongly predictive of CIPN severity. Future prospectively designed studies that assess non-amino acid metabolomics predictors are encouraged.

Successful management and recovery of a dog with immune‐mediated thrombocytopenia following vincristine overdose

Objective

Case Summary

New or Unique Information Provided

Characteristics and patterns of pediatric chemotherapy-induced peripheral neuropathy: A systematic review

This systematic review provides a high-quality synthesis of the empirical evidence regarding chemotherapy-induced peripheral neuropathy (CIPN) characteristics and patterns described in studies of children who received neurotoxic chemotherapy to treat cancer. PubMed, CINAHL, PsycINFO, and Embase were searched for articles published 2009 - 2019, yielding 861. Forty-two papers met the eligibility criteria, including 31 that described characteristics and patterns of vincristine-induced CIPN. Fifty-seven percent of articles were of low to moderate quality; measurement flaws were the most common limitations. The reported CIPN incidence varies widely (2.8%-100%) depending on risk factors (e.g., race) and the measurement approach. Incidence rates of sensory, motor, autonomic CIPN, and pain were 12-28%, 50-72%, 0.8-83% and 5.7-44%, respectively. The evidence suggests that sensory and motor neuropathy, pain, and functional deficits are common and can persist into adulthood. Caucasian race is a risk factor and, contrary to prior thinking, cumulative chemotherapy dosage alone does not predict CIPN severity. The influence of other risk factors is less clear, and studies to date have not explored potential interactions among race, genetics, age, sex, drug metabolism, and nutritional status, among other factors.

Vincristine-Induced Peripheral Neuropathy (VIPN) in Pediatric Tumors: Mechanisms, Risk Factors, Strategies of Prevention and Treatment

Vincristine-induced peripheral neurotoxicity (VIPN) is a very common side effect of vincristine chemotherapy among pediatric patients with cancer. Neuropathy may be sensory, motor and/or autonomic, with consequent reduction, delay or discontinuation of vincristine-chemotherapy, but also pain, disability, reduced quality of life of patients and an increase in medical costs. Vincristine acts out its antineoplastic function by altering the normal assembly and disassembly of microtubules, with their consequent mitosis block and death. Vincristine leads to VIPN through a complex mechanism of damage, which occurs not only on the microtubules, but also on the endothelium and the mitochondria of nerve cells. Furthermore, both patient-related risk factors (age, race, ethnicity and genetic polymorphisms) and treatment-related risk factors (dose, time of infusion and drug–drug interactions) are involved in the pathogenesis of VIPN. There is a lack of consensus about the prophylaxis and treatment of VIPN among pediatric oncologic patients, despite several molecules (such as gabapentin, pyridoxine and pyridostigmine, glutamic acid and glutamine) having been already investigated in clinical trials. This review describes the molecular mechanisms of VIPN and analyzes the risk factors and the principal drugs adopted for the prophylaxis and treatment of VIPN in pediatric patients with cancer.

Nutritional traditional and complementary medicine strategies in pediatric cancer: A narrative review

Traditional and complementary medicine (T&CM) strategies are commonly used by pediatric cancer patients. Nutritional approaches to T&CM include bioactive compounds, supplements, and herbs as well as dietary approaches. Pediatric cancer patients and their families commonly request and use nutritional T&CM strategies. We review the potential risks and benefits of nutritional T&CM use in pediatric cancer care and provide an overview of some commonly used and requested supplements, including probiotics, antioxidants, cannabinoids, vitamins, turmeric, mistletoe, Carica papaya, and others. We also discuss the role of specific diets such as the ketogenic diet, caloric restriction diets, whole-food diets, and immune modulating diets. There is a growing body of evidence to support the use of some T&CM agents for the supportive care of children with cancer. However, further study is needed into these agents and approaches. Open communication with families about T&CM use is critical.

Approaches to measure paediatric chemotherapy-induced peripheral neurotoxicity: a systematic review

In children who receive neurotoxic chemotherapy, peripheral neurotoxicity occurs frequently, necessitates dose reduction or treatment cessation, and affects function and long-term quality of life. No treatments exist for peripheral neurotoxicity and few assessment measures are specific to children. We did a systematic review to analyse the published literature concerning the evaluation of assessment measures for paediatric chemotherapy-induced peripheral neurotoxicity. We searched PubMed, CINAHL, PsycINFO, and Embase on Nov 7-8, 2018; of 1409 articles, seven met the inclusion criteria. A total of 335 children (excluding ten healthy controls) were enrolled in the seven studies and the sample sizes ranged from 17 to 86 individuals. 276 (82%) of the 335 children were actively undergoing chemotherapy treatment. Most studies did not comprehensively evaluate the psychometric properties of assessment measures for chemotherapy-induced peripheral neurotoxicity. By use of a narrative analysis that combined approaches from the Joanna Briggs Institute (Adelaide, SA, Australia) and the quality of diagnostic accuracy studies assessment method (known as QUADAS), only one study was deemed high quality. We identified two variants of the Total Neuropathy Score, two grading scales, two semi-objective tests, one patient-reported outcome, and several mobility measures. The National Cancer Institute Common Terminology Criteria for Adverse Events and the Balis grading scales showed lower sensitivity and specificity than the items of the Total Neuropathy Score. Although there is insufficient evidence to support the use of most approaches to assess chemotherapy-induced peripheral neurotoxicity in children, two variants of the Total Neuropathy Score, the pediatric-modified Total Neuropathy Score and the Total Neuropathy Score-pediatric vincristine, are promising but require further testing. Other approaches are less sensitive or less feasible. A patient-reported outcome measure for chemotherapy-induced peripheral neurotoxicity in children is needed.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Integrative Medicine in Childhood Cancer

The diagnosis of cancer in a child leaves parents and families devastated and vulnerable. In an effort to do everything possible, families often choose an integrative medicine approach to their child's care. Surveys have found that 31%-84% of children with cancer use complementary and alternative medicine and most often as supportive care agents. Several systematic reviews have demonstrated a clinical benefit for some select therapies; however, the safety and efficacy of the combination of biological therapies with conventional treatment remain largely unknown and garner concern due to the potential for interactions with conventional therapy. Given the sustained use and potential benefit of integrative medicine, additional research is warranted in pediatric oncology. Utilizing the available literature, clinical providers should aim to conduct open and nonjudgmental discussions with families about the use of integrative medicine so as to guide the safe integration of the two modalities.

A systematic review of integrative clinical trials for supportive care in pediatric oncology: a report from the International Society of Pediatric Oncology, T&CM collaborative

PURPOSE

Traditional and complementary medicine (T&CM) use in children with cancer is well established among high-income, upper middle-income, low-middle-income, and low-income countries (HIC, UMIC, LMIC, LIC, respectively). In HIC, a developing body of evidence exists for several T&CM therapies; however, evidence in other income settings is less well described despite a significantly higher use when compared to reports from HIC. The aim of this systematic review was to evaluate the evidence for T&CM for a variety of supportive care indications among children with cancer.

METHODS

We performed a systematic review following the PRISMA guidelines of randomized, controlled clinical trials from inception through September 2016. Our eligibility criteria were limited to T&CM studies performed in children and adolescents undergoing treatment for a pediatric malignancy.

RESULTS

Of 6342 studies identified, 44 met inclusion criteria. Two clinical trials reported on acupuncture, 1 reported on aromatherapy, 9 evaluated massage therapy, and 32 reported on dietary supplements. Twenty-two studies were performed in HIC, 15 in UMIC, and 7 in LMIC. T&CM therapies were most commonly investigated for the prevention or management of mucositis, weight loss, and febrile neutropenia. Encouraging results were reported for select interventions; however, the majority of studies were classified as poor to fair quality.

CONCLUSION

Our search revealed numerous clinical studies investigating the use of T&CM for supportive care purposes in pediatric oncology in HIC, UMIC, and LMIC. Although limited, these results could inform supportive care resource allocation and indicate where T&CM may serve to fill gaps where access to care may be limited.

Risk-reduction and treatment of chemotherapy-induced peripheral neuropathy

INTRODUCTION

Chemotherapy-induced peripheral neuropathy (CIPN), a common adverse effect of several chemotherapeutic agents, has a significant impact on quality of life and may even compromise treatment efficacy, requiring chemotherapy dose reduction or discontinuation. CIPN is predominantly related with sensory rather than motor symptoms and the most common related cytotoxic agents are platinum compounds, taxanes and vinca alkaloids. CIPN symptoms may resolve after treatment cessation, but they can also be permanent and continue for years. Areas covered: We present an overview of CIPN pathophysiology, clinical assessment, prevention and treatment identified through a Pubmed search. Expert commentary: No substantial progress has been made in the last few years within the field of prevention and/or treatment of CIPN, in spite of remarkable efforts. Continuous research could expand our knowledge about chemotherapeutic-specific neuropathic pathways and eventually lead to the conception of innovative and targeted agents for the prevention and/or treatment of this debilitating chemotherapy adverse effect.

Medication Repurposing in Pediatric Patients: Teaching Old Drugs New Tricks

OBJECTIVES

Gaps in pediatric therapeutics often result in off-label use and specifically, novel uses for existing medications, termed "drug repurposing." Drug Information (DI) queries to a Pediatric Medication Resource Center of a large metropolitan pediatric hospital in New York and inherent difficulties in retrieving evidence-based information prompted a review of current medication repurposing for pediatric patients. The objective included characterization of innovative off-label use of medications Food and Drug Administration (FDA)-approved for 1 or more indications to treat a totally different disorder or indication in pediatric patients.

METHODS

A systematic literature review was conducted to retrieve publications describing repurposed medications in pediatric patients. Excluded was FDA-approved indications used off-label in pediatric patients (e.g., different dose), preclinical data, adult use only, and experimental use. Evidence quality was classified using a modified American Academy of Neurology Level of Evidence. Results were analyzed using χ(2) at p < 0.05.

RESULTS

Over 2000 references were retrieved and reviewed. A total of 101 medications repurposed for novel off-label uses for pediatric patients were identified: 38 for neonates, 74 for children, and 52 for adolescents. Neonates and infants were least likely to receive a medication for a repurposed use. Strong or intermediate evidence existed in 80.2% of cases. The evidence was weak in 19.8%. No significant relationship was observed between the pediatric age group and strength of the literature. Most repurposed uses pertained to generic or widely used medications. Less than 5% of medications were first marketed after 2011.

CONCLUSIONS

While not exhaustive, the present study represents the most comprehensive listing of novel uses exclusive to pediatric patients. Further research is needed to identify the frequency of repurposed uses. The valuable DI role of pharmacists in assessing repurposed uses is of expanding and increasing importance to ensure such uses are evidence-based.

Clinical Analysis of Adverse Drug Reactions between Vincristine and Triazoles in Children with Acute Lymphoblastic Leukemia

Background

Vincristine (VCR) is a major chemotherapy drug for treatment of childhood acute lymphoblastic leukemia (ALL). Triazole antifungal drugs (AFD) are the main agents for the prevention/treatment of invasive fungal infection (IFI), a common complication during the treatment of ALL. This study investigated the adverse drug reactions (ADRs) between VCR and AFD.

Material/Methods

A retrospective study was performed on 68 children with ALL (39 boys and 29 girls, median age: 5 years) who were treated with VCR chemotherapy (a total of 136 cases, including both induction and reinduction phases) from January 2012 to December 2013 in our hospital. These cases were divided into 4 groups: the control group without AFD prevention/treatment (n=44), the Itra group receiving itraconazole oral solution (n=44), the Fluc group receiving intravenous fluconazole (n=42), and the Vori group receiving voriconazole oral tablets (n=6). The ADRs in each group was recorded and compared.

Results

The incidence of ADRs in the Itra and Vori groups were significantly higher compared with the Fluc and the control group (P<0.05). The incidence of ADRs in the Itra group was significantly higher than that in the Vori group, whereas there was no difference in the incidence between the Fluc and control group.

Conclusions

Given the lower incidence of ADRs between VCR and fluconazole compared with voriconazole or itraconazole, it is relatively safer to use fluconazole in ALL patients receiving VCR chemotherapy. The occurrence of ADRs should be closely monitored when triazoles must be administered concomitantly with VCR.

Glutamic acid not beneficial for the prevention of vincristine neurotoxicity in children with cancer

BACKGROUND

Vincristine causes known side effects of peripheral sensory, motor, autonomic and cranial neuropathies. No preventive interventions are known.

PROCEDURE

We performed a randomized, placebo-controlled, double-blind trial of oral glutamic acid as a preventive agent in pediatric patients with cancer who would be receiving vincristine therapy for at least 9 consecutive weeks (Stratum 1 = Wilms tumor and rhabdomyosarcoma) or 4 consecutive weeks in conjunction with steroids (Stratum 2 = Acute lymphoblastic leukemia and non-Hodgkin lymphoma). At designated time points, a scored neurologic exam using the Modified Balis Pediatric Scale of Peripheral Neuropathies was performed to document neurologic toxicity.

RESULTS

Between 2007 and 2012, 250 patients were enrolled (Stratum 1 = 50, Stratum 2 = 200). The glutamic acid treated group did not have a significantly lower percentage of neurotoxicity compared to placebo treated group either overall or within stratum or age subgroups. The only subgroup which was suggestive of treatment effect was for age. Patients 13 years or older showed a larger benefit in favor of glutamic acid (P = 0.055) compared to patients less than 13 years (P = 1.00). Constipation was the most frequently reported (14%) Grade II or higher neurotoxicity.

CONCLUSION

Vincristine-associated neurotoxicity in pediatric oncology remains a frequent complication of chemotherapy for multiple diagnoses with an approximate 30% of patients affected. Glutamic acid is not effective for prevention in pre-adolescents. There is a suggestion of benefit in patients 13 years or older, but the study was not designed to provide adequate power to test the treatment effect within this age group alone.

Vincristine-induced polyneuropathy in a child with stage I Wilms' tumour presenting with unilateral abducens nerve palsy

A 4-year-old boy presented with right esotropia while receiving vincristine and dactinomycin for stage I Wilms' tumour according to the National Wilms Tumour Study-5 protocol. On examination, he had isolated limitation of his right lateral gaze. CT of the brain and cerebrospinal fluid examination were normal. A nerve conduction velocity study which was performed on the peripheral nerves revealed predominant motor polyneuropathy compatible with axonal loss involving the upper limbs. The patient had received a cumulative vincristine dose of 17 mg/m(2) before developing esotropia. Vincristine-induced abducens nerve mononeuropathy and subclinical motor polyneuropathy was suspected. Unilateral esotropia markedly improved after the discontinuation of vincristine and a short course of oral pyridoxine treatment.

Neuropathic cancer pain: What we are dealing with? How to manage it?

Cancer pain is a serious health problem, and imposes a great burden on the lives of patients and their families. Pain can be associated with delay in treatment, denial of treatment, or failure of treatment. If the pain is not treated properly it may impair the quality of life. Neuropathic cancer pain (NCP) is one of the most complex phenomena among cancer pain syndromes. NCP may result from direct damage to nerves due to acute diagnostic/therapeutic interventions. Chronic NCP is the result of treatment complications or malignancy itself. Although the reason for pain is different in NCP and noncancer neuropathic pain, the pathophysiologic mechanisms are similar. Data regarding neuropathic pain are primarily obtained from neuropathic pain studies. Evidence pertaining to NCP is limited. NCP due to chemotherapeutic toxicity is a major problem for physicians. In the past two decades, there have been efforts to standardize NCP treatment in order to provide better medical service. Opioids are the mainstay of cancer pain treatment; however, a new group of therapeutics called coanalgesic drugs has been introduced to pain treatment. These coanalgesics include gabapentinoids (gabapentin, pregabalin), antidepressants (tricyclic antidepressants, duloxetine, and venlafaxine), corticosteroids, bisphosphonates, N-methyl-D-aspartate antagonists, and cannabinoids. Pain can be encountered throughout every step of cancer treatment, and thus all practicing oncologists must be capable of assessing pain, know the possible underlying pathophysiology, and manage it appropriately. The purpose of this review is to discuss neuropathic pain and NCP in detail, the relevance of this topic, clinical features, possible pathology, and treatments of NCP.

Drug repurposing in pediatrics and pediatric hematology oncology

Drug 'repurposing', that is, using old drugs for new indications, has been proposed as a more efficient strategy for drug development than the current standard of beginning with novel agents. In this review, we explore the scope of drug repurposing in pediatric hematology oncology and in pediatrics in general. Drugs commonly used in children were identified using the Harriet Lane Handbook (HLH) and searched in PubMed for different uses. Additional drugs were identified by searching PubMed and Google.com for 'drug repurposing' or 'drug repositioning'. Almost 10% of drugs with primary uses in pediatrics have been repurposed in pediatric hematology oncology or pediatrics. The observant clinician, pharmacologist and translational bioinformatician, as well as structural targeting, will have a role in discovering new repurposing opportunities.

Vocal cord palsy after vincristine treatment in a child and the inefficacy of glutamic acid in the prevention of relapse: a case report

INTRODUCTION

Vincristine is an antineoplastic drug with a well known efficacy for the treatment of acute lymphoblastic leukemia and many solid tumors. No more than 20 pediatric patients with vincristine-induced vocal cord palsy have been reported, and to the best of our knowledge this is the first case where glutamic acid was administered with the aim of preventing a relapse of laryngeal dysfunction.

CASE PRESENTATION

The larynx paralysis presented with hoarseness and stridor in a Caucasian 18-month-old girl and spontaneously resolved in about a month. In order to administer a subsequent full dose of vincristine, our patient received oral glutamic acid whose efficacy against vincristine neurological side effects has been previously reported.

CONCLUSIONS

Since in our patient the amino acid proved to be ineffective in the prevention of laryngeal paralysis relapse, we suggest that a dose reduction of vincristine should be preferred by oncologists as an initial approach after a case of drug-induced vocal cord palsy.

Risk of azole-enhanced vincristine neurotoxicity in pediatric patients with hematological malignancies: old problem - new dilemma

One of the most well-known drug interactions in pediatric oncology concerns the co-administration of itraconazole, an antifungal triazole, and vincristine, an antileukemic agent, which seems to enhance the risk of neurotoxicity of the latter, mediated through the cytochrome CYP450 enzyme system. The aim of this article is to review the metabolism of these two drugs, to analyze the published cases with severe triazole-enhanced vincristine neurotoxicity, to discuss the pathophysiological mechanisms of this adverse effect, and to contribute in understanding the differences in triazole-vincristine interaction severity.

Pain in malignant hematology

Pain is frequently experienced by patients with hematological malignancies, although it often receives little attention. Different underlying causes and mechanisms may sustain several pain syndromes in hematological malignant patients. Pain may be due to disease itself, to disease-related complications, to iatrogenic causes or may be associated with unrelated medical conditions. The management of pain in this setting requires a multidisciplinary approach, integrating analgesics and causal interventions. An accurate diagnostic assessment and the identification of the underlying causes and pathogenetic mechanisms may dictate the treatment approach. For most pain patients, the WHO's three-step analgesic scale for cancer pain relief can provide adequate relief with oral options, although difficult-to-treat pain syndromes, requiring a more complex treatment approach, may also be observed.