Clinical trial of folinic acid to reduce vincristine neurotoxicity

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

Objective

Case Summary

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Pediatric Oncology Patients With Vincristine-Induced Recurrent Laryngeal Nerve Palsy: Two Case Reports and a Brief Review of Literature

INTRODUCTION

Vincristine (VCR) is a chemotherapeutic agent used widely in the treatment of hematologic and solid tumors, known to result in neurotoxicity, especially with cumulative administrations. Bilateral vocal fold palsy (VFP) is a rare but life-threatening complication of VCR. We report 2 patients with hepatoblastoma presenting with stridor following VCR treatment and propose a management plan.

METHODS

Electronic medical records of oncology patients treated at a tertiary hospital with VCR-induced VFP were reviewed. Literature review was performed in PubMed using the terms: hoarseness, VFP, stridor, vincristine.

RESULTS

A total of 23 children with VCR-induced VFP were identified from the literature review and adding on our 2 cases. Seventeen (77.3%) were male and 5 (22.7%) were female. The median presenting age was 36.0 months (5-204 months). Acute lymphoblastic leukemia, 15 of 23 (65.2%), was the most common malignancy. Eighteen patients (78.3%) had bilateral VFP and 5 (21.7%) had unilateral VFP. The mean time to VF function recovery was 167.3 days (median: 200.5 days, range: 7-270 days) in the intervention group versus 72.1 days (median: 31.5 days, range: 3-240 days) in the conservative group. One patient in the intervention group had persistent VFP. Sixteen patients (69.6%) were observed, 4 (17.4%) underwent tracheostomy, 1 (4.35%) was intubated, 1 (4.35%) underwent cordectomy, and 1 (4.35%) required positive pressure support. Vincristine was restarted in 12 patients (54.5%), of which 4 developed recurrence of airway symptoms and had to stop VCR.

CONCLUSION

A new-onset hoarseness or stridor in a child on VCR should raise the suspicions of VFP. The assumption of an upper respiratory-induced hoarseness or stridor should be avoided. Decisions regarding readministration of VCR and possible airway interventions should be made via a multidisciplinary team approach.

Intrathecal chemotherapy: potential for medication error

BACKGROUND

The central nervous system is a unique sanctuary site for malignant disease. To ensure optimal disease control, intrathecal (IT) chemotherapy is commonly given in conjunction with standard chemotherapy protocols, thus providing the opportunity for medication errors.

OBJECTIVE

A systematic review of the current literature on medication errors associated with the administration of IT chemotherapy was conducted.

METHODS

English-language literature published from January 1960 through June 2013 was accessed. Case reports, clinical studies, and review articles pertaining to IT medication errors were included in the review. References of all relevant articles were searched for additional citations.

RESULTS

Twenty-two cases of accidental IT overdoses have been reported with methotrexate and 1 with cytarabine. There have been numerous cases of antineoplastic agents intended for administration by the parenteral route being inadvertently given intrathecally. Vincristine has been implicated 31 times (25 deaths), as well as vindesine, asparaginase, bortezomib, daunorubicin, and dactinomycin. This has led to profound toxicity and, commonly, death. Unfortunately, many cases go unrecognized or unreported.

CONCLUSIONS

The best method for eliminating the risk of IT medication errors is to develop effective methods of prevention and incorporate them into oncology and hematology practice internationally. Strategies include abolishing the syringe as a method of vinca alkaloid administration and substituting small-volume intravenous bags, and developing novel methods for intraspinal drug administration.

IMPLICATIONS FOR PRACTICE

The nursing profession is in a unique position to influence change and lead the way in establishing preventative strategies into current practice.

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.

Vincristine-induced unilateral ptosis with serendipitous response to modafinil

Here we describe a scenario of an atypical manifestation of vincristine-induced neurotoxicity, which responded serendipitously to modafinil. Atypical in that this patient had developed a uniocular ptosis, a rare manifestation of vincristine-induced neurotoxicity. The improvement in neurotoxicity after modafinil was started to alleviate morphine-induced sedation was quite noteworthy.

Inadvertent intrathecal vincristine administration: a neurosurgical emergency. Case report

Vincristine has a high neurotoxicity level. If given intrathecally by accident, it can cause ascending radiculomyeloencephalopathy, which is almost always fatal. The authors report a rare case in which vincristine was accidentally injected intrathecally into a 32-year-old man. The patient, who had Burkitt lymphoma, was neurologically intact, and it is likely that his survival was made possible due to aggressive neurosurgical therapy. After immediate cerebrospinal fluid (CSF) aspiration, external ventricular and lumbar drains were placed for CSF irrigation, which was continued for 6 days. This CSF irrigation was combined with 1) the intrathecal administration of fresh-frozen plasma to bind the vincristine and 2) an intravenous antineurotoxic therapy involving pyridoxine, folic acid, and glutamic acid. The patient's first sensorimotor deficits occurred after 2 days, led to an incomplete sensorimotor dysfunction below T-9 within the next 17 days, but progressed no further. Supported by the scarce data culled from the reviewed literature, the authors hypothesize that prolonged CSF irrigation combined with antineurotoxic therapy contributed to the patient's satisfactory outcome. In conclusion, accidental intrathecal vincristine injection requires emergency and adequate neurosurgical therapy.

Long-term clinical outcome after accidental overdose of multiple chemotherapeutic agents

Treatment of non-Hodgkin's lymphoma with the CHOP regimen consists of intravenous cyclophosphamide 750 mg/m2 (day 1), intravenous doxorubicin 50 mg/m2 (day 1), intravenous vincristine 1.4 mg/m2 (day 1), and oral prednisone 100 mg (days 1-5). This regimen is administered in cycles of approximately 3 weeks; a total course of treatment consists of six cycles. We report the case of a 23-year-old woman with diffuse large-cell lymphoma who received an accidental overdose of this chemotherapeutic regimen. The first cycle of her CHOP regimen was initiated (day 1) in our outpatient unit; she was then discharged home. Unfortunately, the patient went to another hospital located in the small city where she lived, and all remaining doses of the total course of treatment were administered over the next 5 consecutive days, with no interruption in therapy. She had received cumulative doses of cyclophosphamide 6000 mg, doxorubicin 420 mg, and vincristine 12 mg. She was transferred to our hospital after she developed pancytopenia, fever, and ileus. With the help of intensive supportive care and symptomatic treatment, the patient recovered and was discharged home after a hospital stay of 25 days. After 56 months, she was free of disease and treatment-related toxicities. Only experienced clinicians should administer chemotherapy, and thorough records must be kept to document the chemotherapy administered, dosages, dates of administration, the procedure used, and the schedule of cycles administered.

Neurologic Complications of Cancer Therapy

Although progress in cancer research is paralleled by the discovery and development of novel chemotherapeutic agents, the benefits of these agents are offset by their side-effect profiles. Of the numerous adverse effects associated with antineoplastic drugs, peripheral neuropathy is the most frequent and is often debilitating. This article reviews the treatment options--both primary and secondary--for neuropathic complications of cancer therapy. Before a potentially neurotoxic chemotherapeutic regimen is started, patients should undergo 1) a baseline neurologic history for possible coexisting risk factors for neuropathy; 2) physical evaluation; and 3) if indicated, electrophysiologic testing, including nerve conduction studies and electromyography. Patients should be followed closely for the development of neuropathic signs and symptoms. When symptoms (eg, paresthesias or pain) or deficits (eg, weakness) develop, their severity and their effect on quality of life will determine whether the neurotoxic chemotherapy should be continued at a lower dose or discontinued. Neuropathic pain should be treated aggressively with a stepwise approach. The decision to initiate therapy should be guided first by the severity of pain and second by the convenience of dosing and the side-effect profile of the medication. Specific antineuropathic pain therapy may begin with a tricyclic antidepressant (TCA), titrated to 100 to 150 mg/d, unless anticholinergic side effects appear before this dosage is reached. The TCA may be replaced by or supplemented with antiepileptic agents, such as gabapentin, which is attractive because of its rapid dose titration (maximum, 3600 mg/d) and minimal interaction with other medications. In addition to pharmacologic therapies targeting symptom management, new therapies directed at preventing the onset or progression of neurotoxicity are desperately needed.

Nerve lesions after therapy for childhood acute lymphoblastic leukemia

BACKGROUND

The objective of the current study was to use somatosensory evoked potentials (SEP) to detect signs of nerve lesions in the peripheral nerve and in the central nervous system (CNS) after 3 years of treatment for childhood acute lymphoblastic leukemia (ALL).

METHODS

The somatosensory potentials evoked by stimulation of the median nerve and posterior tibial nerve were recorded in 31 children with ALL after 3 years of therapy. All patients were examined clinically. The 14 standard risk patients had been treated with chemotherapy according to the Nordic regimen, and the 17 intermediate risk or high risk patients had been treated with chemotherapy and cranial irradiation according to the ALL BFM-83 protocol.

RESULTS

A decrease in amplitudes was observed at the brachial plexus and spinal cord (C7) in the median SEP, and at the knee, spinal cord (Th12), and cortex in the tibial SEP, indicating axonal injury within the entire CNS in the patients with ALL compared with healthy age-, gender-, and height-matched controls. Prolongation of the SEP latencies was found within the spinal cord, indicating demyelination. These SEP changes had persisted for 2 years since the last injection/infusion of vincristine or methotrexate, which are the principal neurotoxic drugs used in chemotherapy for ALL. Clinical signs of nerve injury such as depressed deep tendon reflexes and gross or fine motor difficulties were found in approximately 33% of the patients and dysdiadochokinesia in 50%.

CONCLUSIONS

Treatment of ALL in children principally with vincristine and methotrexate causes long-standing axonal injury throughout the nervous system and demyelination within the spinal cord. These changes are associated with clinical neurologic findings.

In vivo modulation of vincristine-induced neurotoxicity in Lymnaea stagnalis, by the ACTH(4-9) analogue Org 2766

The use of the cytostatic agent vincristine (VCR) is limited by the occurrence of peripheral neuropathy. This side-effect is probably caused by interference with axonal microtubules. VCR depolymerizes microtubules and reacts with tubulin to form paracrystals. The potential of a neurotrophic ACTH(4-9) analogue, Org 2766, to counteract peripheral neuropathy caused by cytostatic agents is being investigated. In the present ultrastructural study, modulatory effects of Org 2766 on VCR-induced neurotoxicity were studied in vivo in neurons of the pond snail Lymnaea stagnalis, which has been shown previously to be a suitable test system to investigate neurotoxic side-effects of cytostatic agents. 24 h after treatment with VCR (25 microM), 68.4 +/- 34.7 paracrystals were counted per cross-section of the cerebral commissure and the number of microtubules in the axons had been lowered to 46% of the control level. After a survival period of two weeks all paracrystals had disappeared. By that time, no recovery of the axonal microtubular system could be observed. However, post-treatment with Org 2766 (10(-6) M) on day 6 after VCR treatment had induced a significant increase in the number of microtubules (+55%) on day 7. This beneficial effect lasted for the rest of the experimental period (14 days). These results suggest that post-treatment with Org 2766, i.e. after VCR clearance, can induce long-lasting beneficial effects on VCR-induced neurotoxicity in vivo.

Effects of the ACTH(4-9) analogue, ORG 2766, on vincristine cytotoxicity in two human lymphoma cell lines, U937 and U715

The use of cytotoxic drug vincristine (VCR) is limited by the occurrence of peripheral neuropathy. A neurotrophic ACTH(4-9) analogue, ORG 2766, is being studied for its protective effect. Possible modulatory effects of ORG 2766 on tumour cell growth and interference with the cytotoxic efficacy of VCR were studied in two human lymphoma cell lines, U937 and U715. The effects of ORG 2766 on cell growth and survival and on VCR-mediated cytotoxicity were investigated using two MTT-based assays to study direct cytotoxic effects and to assess residual growth after pretreatment. Treatment with ORG 2766 alone had no effect on cell growth and survival. Neither did this drug affect VCR cytotoxicity. However, after 96 h pretreatment with ORG 2766 and a culture period of 7 days, a reduction in residual growth and a potentiation of VCR-induced inhibition of growth capacity was observed in U715 cells, and to some extent also in U937 cells. It is concluded that ORG 2766 has no stimulatory effects on tumour growth and does not negatively interfere with VCR-mediated cytotoxicity. Rather it enhances the cytostatic effect of VCR. It is suggested that ORG 2766 can safely be used in clinical trials investigating the ability of ORG 2766 to counteract VCR-induced neurotoxicity.

The clinical pharmacology and use of antimicrotubule agents in cancer chemotherapeutics

Although there has been a rapid expansion of the number of classes of compounds with antineoplastic activity, few have played a more vital role in the curative and palliative treatment of cancers than the antimicrotubule agents. Although the vinca alkaloids have been the only subclass of antimicrotubule agents that have had broad experimental and clinical applications in oncologic therapeutics over the last several decades, the taxanes, led by the prototypic agent taxol, are emerging as another very active class of antimicrotubule agents. After briefly reviewing the mechanisms of antineoplastic action and resistance, this article comprehensively reviews the clinical pharmacology, therapeutic applications, and clinical toxicities of selected antimicrotubule agents.

Evolution of neuropathy and myopathy during intensive vincristine/corticosteroid chemotherapy for non-Hodgkin's lymphoma

Neuropathy and myopathy are common sequelae of intensive chemotherapy protocols that contain vincristine and corticosteroids. The authors prospectively monitored the evolution of neuropathy and myopathy during an intensive 12-week chemotherapy program for patients with intermediate and high-grade non-Hodgkin's lymphoma. In this study, vincristine was administered by bolus injection followed by a 3-day continuous intravenous (IV) infusion (total dose of 2.0 mg/m2 every other week); the maximum dose of vincristine was not arbitrarily limited. Cronassial, a mixture of four naturally occurring gangliosides, was administered in a randomized double-blind test to evaluate whether this agent could prevent vincristine-induced neuropathy. High doses of dexamethasone (50 mg/d for 3 days weekly or every other week) were also prescribed. Patients were monitored every 4 weeks with comprehensive physical and neurologic examinations and electrophysiologic studies of peripheral nerve function. Twenty-seven patients were fully evaluable. Weakness was a prominent adverse reaction in this study, and all patients had moderate to severe signs and symptoms of neuropathy and myopathy. Cronassial (100 mg) administered by intramuscular (IM) injection daily provided no protection against the development of neuropathic symptoms. Vincristine typically impaired fine-motor coordination initially, whereas corticosteroids were associated with delayed development of proximal muscle weakness. Results of electrodiagnostic studies did not add to the clinical examination results. The authors conclude that symptomatic weakness due to neuropathy or myopathy appears in a predictable manner during intensive vincristine/corticosteroid-based treatment protocols. Simple clinical tests can be used to rapidly distinguish between toxic effects due either to vincristine or corticosteroids, and routine implementation of these tests can prevent inappropriate dose attenuation of these agents.

Clinical pharmacology of cancer chemotherapy in children

The pharmacokinetics of most anticancer drugs are highly variable in children, and are commonly different when children are compared to adults. Several recent studies have demonstrated that variability in systemic exposure due to interpatient pharmacokinetic variability, may be related to the probability of oncolytic effects or toxicity for some anticancer drugs. This review has exemplified differences in the clinical pharmacology of several anticancer drugs, when children are compared to adults. Such age-related differences in the pharmacokinetics and pharmacodynamics of these drugs, together with biologic differences between pediatric and adult cancers, provide the rationale for systematically conducting pediatric phase I through IV studies of anticancer drugs and denote the risks of relying on adult trials to identify new therapeutic strategies for childhood cancers.

Amelioration of vincristine neurotoxicity by glutamic acid

Neurotoxicity is the principal limiting side effect of the widely used antitumor agent, vincristine. Following evaluation of glutamic acid as a potential modifier of vincristine toxicity in preclinical studies in mice and a preliminary clinical trial, a prospective, double-blind, placebo-controlled, randomized trial was conducted by the Piedmont Oncology Association. Of 87 patients entered into the study, 84 were evaluable, including 42 patients who were randomly assigned to receive vincristine 1.0 mg/m2 weekly for six doses and 42 patients who were assigned to receive glutamic acid 500 mg orally three times daily plus vincristine. The following neurotoxic signs and symptoms were evaluated before each dose of vincristine: reflex changes, paresthesias, constipation, strength, and mental changes. Loss of the Achilles tendon reflex, an objective parameter, was noted in 19 percent of patients receiving glutamic acid and 42 percent of control subjects (p = 0.03). Development of moderate to severe paresthesias, a subjective parameter, occurred in 19 percent of the glutamic acid group and 36 percent of the placebo group (p = 0.09). Overall moderate neurotoxicity (6 units or more), determined by adding the grade of each neurotoxic parameter for the weekly clinic visit in which maximum neurotoxicity occurred, was observed in 21 percent of patients receiving glutamic acid and 43 percent of those in the control group (p = 0.04). Hematologic and gastrointestinal side effects occurred with similar frequency in the two groups. The administration of glutamic acid has decreased vincristine-induced neurotoxicity without any attendant side effects.