Myelopathy due to intrathecal chemotherapy: report of six cases

Metabolic and Toxic Myelopathies

OBJECTIVE

This article reviews the clinical presentation, diagnostic evaluation, and treatment of metabolic and toxic myelopathies resulting from nutritional deficiencies, environmental and dietary toxins, drugs of abuse, systemic medical illnesses, and oncologic treatments.

LATEST DEVELOPMENTS

Increased use of bariatric surgery for obesity has led to higher incidences of deficiencies in nutrients such as vitamin B12 and copper, which can cause subacute combined degeneration. Myelopathies secondary to dietary toxins including konzo and lathyrism are likely to become more prevalent in the setting of climate change leading to drought and flooding. Although modern advances in radiation therapy techniques have reduced the incidence of radiation myelopathy, patients with cancer are living longer due to improved treatments and may require reirradiation that can increase the risk of this condition. Immune checkpoint inhibitors are increasingly used for the treatment of cancer and are associated with a wide variety of immune-mediated neurologic syndromes including myelitis.

ESSENTIAL POINTS

Metabolic and toxic causes should be considered in the diagnosis of myelopathy in patients with particular clinical syndromes, risk factors, and neuroimaging findings. Some of these conditions may be reversible if identified and treated early, requiring careful history, examination, and laboratory and radiologic evaluation for prompt diagnosis.

Progressive Lower Extremity Paralysis Caused by Intrathecal MTX-Induced Myelopathy Mimicking Guillain-Barre Syndrome: A Case Report

Methotrexate (MTX) is commonly used in intrathecal chemotherapy for patients with acute lymphocytic leukemia (ALL) to prevent central nervous system (CNS) involvement. However, the use of MTX-based chemotherapy can lead to rare yet severe complications, such as MTX-induced myelopathy. Here, we report the case of MTX-induced myelopathy initially misdiagnosed as Guillain-Barre syndrome, leading to a delay in diagnosis and treatment. We present a case of a 39-year-old male with a history of B-cell acute lymphoblastic leukemia (B-ALL) who experienced bilateral foot paresthesia and progressive lower extremity weakness after intrathecal methotrexate (MTX) treatment. Initially, the patient was suspected as having Guillain-Barre syndrome (GBS) due to similar clinical features and nerve conduction studies. The patient received intravenous immunoglobulin (IVIG) treatment, but his condition worsened. T2-weighted images of the thoracic spinal cord revealed high signal intensity in both lateral and posterior columns, typically associated with subacute combined degeneration. However, elevated vitamin B12 levels ruled out SCD in this case. Based on the aforementioned findings, intrathecal methotrexate-induced myelopathy was diagnosed. This case highlights the diagnostic challenge posed by the similarity in clinical presentation between MTX-induced myelopathy and GBS. Differentiating between these conditions is critical for appropriate management. Prompt recognition and treatment with folate metabolism compounds may mitigate neurological sequelae.

The leptomeninges as a critical organ for normal CNS development and function: First patient and public involved systematic review of arachnoiditis (chronic meningitis)

BACKGROUND & IMPORTANCE

This patient and public-involved systematic review originally focused on arachnoiditis, a supposedly rare "iatrogenic chronic meningitis" causing permanent neurologic damage and intractable pain. We sought to prove disease existence, causation, symptoms, and inform future directions. After 63 terms for the same pathology were found, the study was renamed Diseases of the Leptomeninges (DLMs). We present results that nullify traditional clinical thinking about DLMs, answer study questions, and create a unified path forward.

METHODS

The prospective PRISMA protocol is published at Arcsology.org. We used four platforms, 10 sources, extraction software, and critical review with ≥2 researchers at each phase. All human sources to 12/6/2020 were eligible for qualitative synthesis utilizing R. Weekly updates since cutoff strengthen conclusions.

RESULTS

Included were 887/14286 sources containing 12721 DLMs patients. Pathology involves the subarachnoid space (SAS) and pia. DLMs occurred in all countries as a contributor to the top 10 causes of disability-adjusted life years lost, with communicable diseases (CDs) predominating. In the USA, the ratio of CDs to iatrogenic causes is 2.4:1, contradicting arachnoiditis literature. Spinal fusion surgery comprised 54.7% of the iatrogenic category, with rhBMP-2 resulting in 2.4x more DLMs than no use (p<0.0001). Spinal injections and neuraxial anesthesia procedures cause 1.1%, and 0.2% permanent DLMs, respectively. Syringomyelia, hydrocephalus, and arachnoid cysts are complications caused by blocked CSF flow. CNS neuron death occurs due to insufficient arterial supply from compromised vasculature and nerves traversing the SAS. Contrast MRI is currently the diagnostic test of choice. Lack of radiologist recognition is problematic.

DISCUSSION & CONCLUSION

DLMs are common. The LM clinically functions as an organ with critical CNS-sustaining roles involving the SAS-pia structure, enclosed cells, lymphatics, and biologic pathways. Cases involve all specialties. Causes are numerous, symptoms predictable, and outcomes dependent on time to treatment and extent of residual SAS damage. An international disease classification and possible treatment trials are proposed.

Case of neuromyelitis optica: bilateral sensorineural hearing loss and transverse myelopathy following intrathecal chemotherapy

Neurotoxicity from intrathecally administered chemotherapeutic drugs is frequent, particularly with some agents like methotrexate, which are more prone to developing adverse effects. Myelopathy ranks among the most frequently reported neurological entities; with the diagnosis being straightforward, after ruling out infectious, metabolic, autoimmune or paraneoplastic causes. Scarcity of cases precludes evidence-based recommendations for the management of these complications. The most common therapeutic approach consists of the suspension of chemotherapy, exclusion of infectious and neoplastic causes, with prompt administration of high-dose steroids. We report a 21-year-old patient with acute lymphoblastic leukaemia, who developed acute transverse myelitis and bilateral sensorineural hearing loss, after five rounds of intrathecal methotrexate and cytarabine. Although neurotoxicity from both agents has been documented, this combination has not been previously reported.

Central Nervous System Complications in Children Receiving Chemotherapy or Hematopoietic Stem Cell Transplantation

Therapy-related neurotoxicity greatly affects possibility of survival and quality of life of pediatric patients treated for cancer. Central nervous system (CNS) involvement is heterogeneous, varying from very mild and transient symptoms to extremely severe and debilitating, or even lethal syndromes. In this review, we will discuss the broad scenario of CNS complications and toxicities occurring during the treatment of pediatric patients receiving both chemotherapies and hematopoietic stem cell transplantation. Different types of complications are reviewed ranging from therapy related to cerebrovascular with a specific focus on neuroradiologic and clinical features.

Implications of Intrathecal Chemotherapy for Anaesthesiologists: A Brief Review

Intrathecal chemotherapy is routinely prescribed in medical oncology practice, either for prophylaxis or for treatment of leptomeningeal disease due to a primary haematological disease or a metastatic disease due to any other malignancy. As these groups of patients are coagulopathic either because of the disease per se or due to systemic chemotherapy, lumbar puncture in them is considered challenging and is expected to be performed by an anaesthesiologist because of their expertise in this procedure. However, the challenge is not only in performing the lumbar puncture safely but also in dealing with other issues like explaining and handling complications that can happen either due to the drug injected intrathecally or due to a neurodeficit occurring either due to the underlying coagulopathy or due to the progression of leptomeningeal disease.

Spinal Nerve Root Enhancement on MRI Scans in Children: A Review

Spinal nerve root enhancement in pediatric patients is generally nonspecific, and clinical and laboratory correlation is essential. Nerve root enhancement indicates lack of integrity of the blood-nerve barrier. In this review, we will present a range of pediatric conditions that can present with spinal nerve root enhancement including inflammatory, infectious, hereditary, and neoplastic causes. Familiarity with the various pathologic entities associated with spinal nerve root enhancement is important for a concise differential diagnosis in the appropriate clinical setting. This will avoid unnecessary additional investigations.

Myelopathy following intrathecal chemotherapy in adults: a single institution experience

Methotrexate and cytarabine arabinoside are frequently administered intrathecally in the prophylaxis and treatment of patients with hematological malignancies. Myelopathy as a complication of intrathecal (IT) chemotherapy is rare in adults, with most of the cases described in the literature occurring in the pediatric population. Between January 2010 and March 2014, 587 newly diagnosed B cell acute lymphoblastic leukemia and 24 chronic myeloid leukemia lymphoid blast phase patients were seen at The University of Texas MD Anderson Cancer Center. This case series discusses seven adult cases deemed to have IT chemotherapy-induced myelopathy between 2010 and 2014 at MD Anderson Cancer Center. Five out of the seven patients had T2 abnormalities involving the dorsal columns of the spinal cord. An elevated myelin basic protein level was noted in the two patients in whom it was checked. The wide range of dosage and timing with respect to IT chemotherapy administration suggests an idiosyncratic reaction or individual threshold to the development of myelopathy. By describing the largest case series of myelopathy in adults, we aim to raise awareness about this rare albeit devastating complication. Based on the seven cases described we would recommend-MRI of the spine with T2-weighted imaging in the sagittal and axial planes in leukemia patients with unexplained myelopathy and consideration to delay IT chemotherapy until after an extensive work-up to rule out CNS leukemia. Though more data are needed on the use of folate metabolites, preliminary results have shown some promise in the treatment of methotrexate-induced myelopathy and may be a potential consideration for future patients suspected to have chemotherapy induced myelopathy.

Dorsal column myelopathy following intrathecal chemotherapy for acute lymphoblastic leukemia

OBJECTIVE/CONTEXT: To describe a distinctive clinical and radiographic pattern of myelopathy following intrathecal chemotherapy. Myelopathy is a rare complication of intrathecal chemotherapy used in the treatment of acute lymphoblastic leukemia (ALL). We present a 42-year-old female with T-cell ALL who developed a myelopathy primarily involving the dorsal columns.

METHOD

Case report and literature review.

FINDINGS

Within 24 hours of an injection of intrathecal methotrexate, cytarabine, and hydrocortisone, the patient developed ascending lower limb numbness and balance difficulties progressing to the inability to ambulate. Clinical examination showed profound loss of lower limb proprioception and light touch sensation below T5, mild proximal limb weakness, but preserved pinprick and temperature sensation with intact bowel and bladder function. Initial thoracic and lumbar spine magnetic resonance imaging (MRI) at 1 week revealed no abnormalities. However, repeat imaging at 6 weeks showed abnormal signal in the posterior cord with sparing of the anterior and lateral columns, diffusely involving the lower cervical cord through the conus medullaris. Dermatomal somatosensory-evoked potential (DSEP) conduction abnormalities were consistent with thoracic myelopathy. An empiric trial of high-dose intravenous corticosteroids during inpatient rehabilitation more than 6 weeks later produced no significant clinical improvement.

CONCLUSION/CLINICAL RELEVANCE

Preferential and persistent dorsal column myelopathy is a distinctive clinical and radiographic presentation of a rare complication of intrathecal chemotherapy. The MRI abnormalities were initially absent, but evolved to consist of multi-level spinal cord T2 and STIR hyperintensity with regional gadolinium enhancement. DSEPs more accurately reflected the clinical level of spinal cord dysfunction.

Lateral and dorsal column hyperintensity on magnetic resonance imaging in a patient with myelopathy associated with intrathecal chemotherapy

Chemotherapy-related myelopathy mimicking subacute combined degeneration (SCD) has rarely been reported. We encountered a 35-year-old female with sensory ataxia after intrathecal chemotherapy. Spinal magnetic resonance imaging showed localized abnormal signal areas in the lateral and dorsal white matter, mimicking SCD. Diffusion imaging showed restricted water diffusion and increased microstructural complexity, and cerebrospinal fluid analysis showed increased levels of myelin basic proteins, indicating demyelinating myelopathy. Advanced diffusion imaging can provide more information on the microstructure of chemotherapy-related myelopathy.

Methotrexate-induced myelopathy mimicking subacute combined degeneration of the spinal cord

Methotrexate (MTX), a folate antagonist, is widely used to treat hematological malignancies. Although it is known to cause myelopathy, little is known about the pathophysiology and natural history of this myelopathy. We describe a 42-year-old woman with acute lymphoblastic leukemia who was treated with chemotherapy consisting of intrathecal MTX who developed a progressive myelopathy. The myelopathy mimicked, radiologically, subacute combined degeneration (SACD) of the spinal cord. This myelopathy mimicking SACD could be explained by the folate antagonism of MTX. The progressive clinical signs and serial MRI in this patient further our understanding of the natural progression of this myelopathy.

Spinal cord disease in patients with cancer

PURPOSE OF REVIEW

Spinal cord disease is not uncommon in patients with systemic cancer. Most cases are due to epidural tumor metastases with resulting cord compression, although intramedullary spinal cord metastases, radiation myelopathy, and myelopathic complications of chemotherapy must be considered.

RECENT FINDINGS

Techniques for surgical decompression of the spinal cord in patients with epidural tumor have improved significantly over the past decade. Several studies have demonstrated improved neurologic outcome in a subset of patients with epidural spinal cord compression treated surgically.

SUMMARY

This article outlines the clinical features, radiographic findings, and differential diagnosis of spinal cord disease in patients with cancer and describes the therapeutic approach to these patients. Early identification and treatment of patients with epidural spinal cord compression is critical to maintaining neurologic function and preserving quality of life.

Central nervous system chemotoxicity during treatment of pediatric acute lymphoblastic leukemia/lymphoma

In the last decades, increasing success rates are being obtained in the chemotherapy of pediatric leukemia and lymphoma. However, the cornerstone of this treatment is still formed by a reduced number of drugs with a highly toxic profile. In particular, central nervous system complications remain a challenging clinical problem, requiring rapid detection and prompt treatment to limit permanent damage. Furthermore, clinicians are often challenged to discriminate between CNS involvement by the disease, toxicity of drugs or infections. This clinically oriented review will help recognize and handle the main neurologic adverse effects induced by chemotherapy in pediatric patients with lymphoblastic leukemia/lymphoma. Different clinical entities and putative drugs involved are discussed in each chapter, with clinical cases illustrating the most relevant and challenging events. In addition, specific clinical-radiological patterns of some of these neurologic events are detailed. Finally, the role of pharmacogenetics, with special focus on those polymorphisms that could help explain the occurrence of neurotoxicity, is also discussed.

Granulocytic sarcoma of the knee and the spine as aleukemic relapse of acute myeloid leukemia in a child

Granulocytic sarcoma is a very rare disease in childhood, which may precede the clinical manifestations of acute myeloid leukemia or may occur as a relapse of a nonleukemic acute myeloid leukemia. It is a malignant, solid tumor consisting of myeloblasts or immature myeloid cells occurring in extramedullary sites. We report interesting magnetic resonance images of a nonleukemic relapse of acute myeloid leukemia in a child presenting as a granulocytic sarcoma unusually localized to the knee and spine.

Clinical features of encephalopathy in children with cancer requiring cranial magnetic resonance imaging

We analyzed acute neurotoxic problems attributable to chemotherapy or immunosuppression in the context of childhood neoplastic diseases, based on clinical and neuroradiologic findings. This retrospective single-center study reviewed the acute neurologic complications of 62 children receiving conventional chemotherapy or hematopoietic stem cell transplantation from July 2005-July 2008. We excluded patients with central nervous system metastasis and various neurotoxic manifestations not usually requiring cranial magnetic resonance imaging. Of 62 patients, 12 (19.3%) developed acute neurologic complications. The most common complications included posterior reversible encephalopathy syndrome in six of 12 (50%) patients, and Wernicke's encephalopathy in three of 12 (25%) patients. Other complications included chemical arachnoiditis, grey matter injury induced by postchemotherapeutic angiopathy, and leukoencephalopathy. Posterior reversible encephalopathy syndrome was accompanied by hypertensive episodes in most patients (5/6), and Wernicke's encephalopathy was evident with altered mental status in malnourished children. These data indicate that posterior reversible encephalopathy syndrome and Wernicke's encephalopathy are the predominant complications in children undergoing chemotherapy or hematopoietic stem cell transplantation. Early radiologic and clinical evaluation and prompt treatment for these complications are necessary to prevent their progression to irreversible brain damage.

[Neurological complications of neurooncological therapy]

Neurological complications of therapeutic procedures for brain tumors are increasingly being recognized. These encompass the classic types of central and peripheral neurotoxicity, such as radiotherapy-induced leukoencephalopathy and platinum-induced neuropathy. However, the advent of novel protocols and targeted therapeutics has expanded the spectrum of neurological complications. A problem of considerable importance is pseudoprogression after radiochemotherapy with temozolomide. Among the new targeted drugs complications of therapy with bevacizumab are the subject of intense discussion. In this review article the neurotoxic potential of intrathecal chemotherapy, kinase inhibitors, immunological strategies and local therapies are summarized. Knowledge about neurological complications of brain tumor therapy procedures is important for risk assessment and patient information.

Somatosensory evoked potential for detection of subclinical neuropathy in Egyptian children with acute lymphoblastic leukaemia

To evaluate neurological changes developing during paediatric Acute Lymphoblastic Leukaemia (ALL) therapy clinically and through electrophysiological Study of Somatosensory Evoked Potentials (SSEPs) changes in different phases of therapy. Thirty five-ALL patients with age range from 3-14 years were included compared to 30 healthy controls. History, neurological examination, complete blood counts, cytological examination of bone marrow aspirate and cerebrospinal fluid with Measurement of Serum Methotrexate (MTX) were done. The SSEPs were performed and patients subjected to another SSEP with measurement of serum MTX level before and 10 days after intra-thecal injection (IMTX). Clinical neurological findings in patients after induction were depressed deep tendon reflexes (43.3%), hypotonia (28.6%), lost pain sensation (28.6%), muscle weakness (17.1%) and movement disorders (17.1%). Percentage of delayed SSEPs after induction were at levels of brachial plexus (28.6%), spinal cord (68.6%), cortical conduction (31.4%), ERB-N13 Inter Peak Latency (IPL) (74.3%) and N13-N20 IPL (17.1%) in the studied patients. Significant prolonged latency of N13 (p = 0.005), N20 (p = 0.04) and IPL of ERB-N 13 (p = 0.005), N13-N20 (p = 0.01), Inter-Side Difference (ISD) of N13 (p = 0.01), ERB-N13 (p = 0.02) and N13-N20 (p = 0.03) after induction compared to values at diagnosis. Significant positive correlation were found between serum MTX after IMTX with N13-N20 IPL (p = 0.01), N20 ISD (p = 0.03) with significant prolongation in N20 latency, N13-N20 IPL and ISD of N20 compared to values before injection. ALL patients have prolonged latency of SSEPs at cervical cord and cortical levels which increased after IMTX due to axonal injury throughout the cord. SSEPs could be an early diagnostic tool for subclinical neuropathy.

DNA repair alterations in children with pediatric malignancies: novel opportunities to identify patients at risk for high-grade toxicities

PURPOSE

To evaluate, in a pilot study, the phosphorylated H2AX (γH2AX) foci approach for identifying patients with double-strand break (DSB) repair deficiencies, who may overreact to DNA-damaging cancer therapy.

METHODS AND MATERIALS

The DSB repair capacity of children with solid cancers was analyzed compared with that of age-matched control children and correlated with treatment-related normal-tissue responses (n = 47). Double-strand break repair was investigated by counting γH2AX foci in blood lymphocytes at defined time points after irradiation of blood samples.

RESULTS

Whereas all healthy control children exhibited proficient DSB repair, 3 children with tumors revealed clearly impaired DSB repair capacities, and 2 of these repair-deficient children developed life-threatening or even lethal normal-tissue toxicities. The underlying mutations affecting regulatory factors involved in DNA repair pathways were identified. Moreover, significant differences in mean DSB repair capacity were observed between children with tumors and control children, suggesting that childhood cancer is based on genetic alterations affecting DSB repair function.

CONCLUSIONS

Double-strand break repair alteration in children may predispose to cancer formation and may affect children's susceptibility to normal-tissue toxicities. Phosphorylated H2AX analysis of blood samples allows one to detect DSB repair deficiencies and thus enables identification of children at risk for high-grade toxicities.

Chemotherapy-related side effects in childhood acute lymphoblastic leukemia in Indonesia: parental perceptions

Noncompliance with prescribed medication has been associated with increased chance of relapse and poor outcome. Side effects may be an important cause of noncompliance. Fifty-one parents of children with acute lymphoblastic leukemia in a tertiary care hospital in Indonesia were interviewed about their perception of side effects and their impact on treatment noncompliance and daily activities. A symptom checklist assessing 13 common symptoms was used to examine side effects. During chemotherapy, childhood acute lymphoblastic leukemia patients suffered from psychological as well as physical side effects. The most frequent side effect reported by parents was behavior alteration (92%). Second and third in frequency were increased appetite and infections, reported by 88% and 83% of parents, respectively. The most severe side effects were leg weakness, increased appetite, and behavior alteration. The overall frequency of side effects was weakly correlated to noncompliance. Reducing the impact of side effects may increase compliance with the treatment.

A patient with acute myeloblastic leukemia who presented with conus medullaris syndrome and review of the literature

In childhood, the conus medullaris syndrome owing to leukemia is rare. Here, a 12-year-old boy with acute myeloblastic leukemia, maxillary mass, and conus medullaris syndrome is reported. A biopsy from the maxillary mass revealed "granulocytic sarcoma." Lumbosacral magnetic resonance imaging revealed clumped and thickened cauda equina nerve roots, epidural and periradicular diffuse soft tissue, which was enhanced with gadolinium. Cerebrospinal fluid revealed elevated protein but no cells. Chemotherapy and local radiotherapy for both the face and the spine, yielded bone marrow remission and abatement in neurologic and radiologic findings, but he developed bone marrow relapse and died because of sepsis.

Impact of the methotrexate administration dose on the need for intrathecal treatment in children and adolescents with anaplastic large-cell lymphoma: results of a randomized trial of the EICNHL Group

PURPOSE

To compare the efficacy and safety of two methotrexate doses and administration schedules in children with anaplastic large-cell lymphoma (ALCL).

PATIENTS AND METHODS

This randomized trial for children with ALCL was based on the Non-Hodgkin's Lymphoma-Berlin-Frankfurt-Muenster 90 (NHL-BFM90) study protocol and compared six courses of methotrexate 1 g/m2 over 24 hours and an intrathecal injection (IT) followed by folinic acid rescue at 42 hours (MTX1 arm) with six courses of methotrexate 3 g/m2 over 3 hours followed by folinic acid rescue at 24 hours without IT (MTX3 arm). This trial involved most European pediatric/lymphoma study groups and a Japanese group.

RESULTS

Overall, 352 patients (96% ALK positive) were recruited between 1999 and 2005; 175 were randomly assigned to the MTX1 arm, and 177 were assigned to the MTX3 arm. Ninety-two percent of patients received protocol treatment. Median follow-up time is 3.7 years. Event-free survival (EFS) curves were superimposed with 2-year EFS rates (73.6% and 74.5% in the MTX1 and MTX3 arms, respectively; hazard ratio = 0.98; 91.76% CI, 0.69 to 1.38). Two-year overall survival rates were 90.1% and 94.9% in MTX1 and MTX3, respectively. Only two CNS relapses occurred (both in the MTX1 arm). Toxicity was assessed after 2,050 courses and included grade 4 hematologic toxicity after 79% and 64% of MTX1 and MTX3 courses, respectively (P < .0001); infection after 50% and 32% of courses, respectively (P < .0001); and grade 3 to 4 stomatitis after 21% and 6% of courses, respectively (P < .0001).

CONCLUSION

The results of the NHL-BFM90 study were reproduced in this large international trial. The methotrexate schedule of the NHL-BFM90 protocol including IT therapy can be safely replaced by a less toxic schedule of methotrexate 3 g/m2 in a 3-hour infusion without IT therapy.

Intrathecal chemotherapy for hematologic malignancies: drugs and toxicities

Intrathecal (IT) chemotherapy is an important component of the prophylaxis or treatment of hematologic malignancies in the central nervous system (CNS), especially in patients with acute lymphoblastic leukemia and aggressive lymphomas. Different regimens of IT chemotherapies have been formulated, often in conjunction with systemic high-dose chemotherapy leading to penetration of the drugs into the cerebrospinal fluid (CSF). The three commonest IT drugs are methotrexate, cytosine arabinoside (Ara-C), and corticosteroids. The CSF half-lives of methotrexate and Ara-C are much prolonged, a factor to be considered if these drugs are also administered systemically in high doses. Neurotoxicities attributed to IT chemotherapy have been reported, including spinal cord lesions, seizures, and encephalopathy. Spinal cord lesions, manifesting as tetraplegia, paraplegia, and cauda equina syndrome, are the commonest neurotoxicity. It is mostly related to combined IT methotrexate and Ara-C, or Ara-C as the sole IT agent when given at high doses or as a slow-release preparation. Cord lesions rarely recover and patients are left with motor deficits, bowel and urinary disabilities. Seizures and encephalopathy are reported in relatively fewer patients, with variable manifestations and prognosis. Knowledge of the pharmacokinetics, dosing schedules and potential toxicities of IT chemotherapeutic drugs is important in the design of CNS prophylaxis and treatment in hematologic malignancies.

Irreversible paraplegia following one time prophylactic intrathecal chemotherapy in an adult patient with acute lymphoblastic leukemia

We present an adult female patient who developed irreversible paraplegia and areflexia four days post intrathecal chemotherapy with methotrexate, cytosine arabinoside and hydrocortisone. On magnetic resonance imaging (MRI) of the lumbar spine, diffuse gadolinium enhancement of the anterior spinal nerve roots (ventral roots) was detected. Methylprednisolone was intravenously administered at a daily dose of 30mg/kg for three days. Despite this treatment, flaccid weakness in the lower extremities and urinary retention persisted. Following consolidation chemotherapy, no improvement in neurologic status was noted. Six months later, a follow-up MRI revealed severe atrophy of the thoracic spinal cord.

Neurologic toxicities of cancer therapies

Neurologic dysfunction is a well-recognized adverse effect of cancer therapeutics. The most common manifestations include peripheral neuropathy and encephalopathy. Often, symptoms resolve or improve upon removal of the offending agent; therefore, it is essential that clinicians recognize the symptoms and signs of injury. Occasionally, symptoms persist or develop after discontinuation of medication and may culminate in disability and diminished quality of life. As our understanding of neurotoxicity improves, medications with less potential for injury may be developed. In addition, potential antidotes to prevent or reverse injury may emerge. This review focuses on the clinical features, mechanisms, and possible therapeutics of the neurotoxicity of chemotherapy. In particular, oxaliplatin, thalidomide, methotrexate, ifosfamide, cytarabine, amifostine, acetyl-L-carnitine, methylene blue, cytokines, and neurotrophins are discussed.