Age and high-dose methotrexate are associated to clinical acute encephalopathy in FRALLE 93 trial for acute lymphoblastic leukemia in children

Buspirone attenuated methotrexate-induced hippocampal toxicity in rats by regulating Nrf2/HO-1, PPAR-γ, NF-κB/nNOS, and ROS/NLRP3/caspase-1 signaling pathways

Methotrexate (MTX) is a chemotherapeutic agent widely used to treat a variety of tumors. Nonetheless, MTX-induced hippocampal neurotoxicity is a well-defined dose-limiting adverse effect that limits clinical utility. Proinflammatory cytokine production and oxidative stress are possible mechanisms for MTX-induced neurotoxicity. Buspirone (BSP), a partial agonist of the 5-HT1a receptor (5-HT1aR), has emerged as an anxiolytic drug. BSP has been shown to possess antioxidant and anti-inflammatory effects. The current study investigated BSP's potential anti-inflammatory and antioxidant effects in attenuating MTX-induced hippocampal toxicity. Rats received either BSP (1.5 mg/kg) orally for 10 days and MTX (20 mg/kg) i.p. on Day 5. BSP administration markedly protected hippocampal neurons from drastic degenerated neuronal changes induced by MTX. BSP significantly attenuated oxidative injury by downregulating Kelch-like ECH-associated protein 1 expression while potently elevating hippocampal Nrf2, heme oxygenase-1, and peroxisome proliferator-activated receptor expression. BSP dampened inflammation by reducing NO2 - , tumor necrosis factor-alpha, IL-6, and interleukin 1 beta levels mediated by downregulating NF-κB and neuronal nitric oxides synthase expression. Moreover, BSP potently counteracted hippocampal pyroptosis by downregulating NLRP3, ASC, and cleaved-caspase-1 proteins. Therefore, BSP may represent a promising approach to attenuate neurotoxicity in patients receiving MTX.

Choroid plexus-CSF-targeted antioxidant therapy protects the brain from toxicity of cancer chemotherapy

For many cancer patients, chemotherapy produces untreatable life-long neurologic effects termed chemotherapy-related cognitive impairment (CRCI). We discovered that the chemotherapy methotrexate (MTX) adversely affects oxidative metabolism of non-cancerous choroid plexus (ChP) cells and the cerebrospinal fluid (CSF). We used a ChP-targeted adeno-associated viral (AAV) vector approach in mice to augment CSF levels of the secreted antioxidant SOD3. AAV-SOD3 gene therapy increased oxidative defense capacity of the CSF and prevented MTX-induced lipid peroxidation in the hippocampus. Furthermore, this gene therapy prevented anxiety and deficits in short-term learning and memory caused by MTX. MTX-induced oxidative damage to cultured human cortical neurons and analyses of CSF samples from MTX-treated lymphoma patients demonstrated that MTX diminishes antioxidant capacity of patient CSF. Collectively, our findings motivate the advancement of ChP- and CSF-targeted anti-oxidative prophylactic measures to relieve CRCI.

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.

Methotrexate-induced Transient Encephalopathy in an Adolescent and Young Adult Patient with Acute Lymphoblastic Leukemia

A 17-year-old girl was diagnosed with acute lymphoblastic leukemia (ALL). After the administration of high-dose methotrexate (MTX) or intrathecal MTX, the patient experienced transient hemiparesis and motor aphasia. Diffusion-weighted magnetic resonance imaging showed a high-intensity lesion in the bilateral centrum semiovale, and a vasospasm was detected in the proximal segment of bilateral A1 on magnetic resonance angiography. Edaravone was administered, and leucovorin rescue treatment was continued; eventually, the patient's neurological symptoms completely resolved. This finding suggested that vasospasm might be a mechanism underlying MTX-induced transient encephalopathy in adolescent and young adult patients with ALL.

Long-term leukoencephalopathy and neurocognitive functioning in childhood sarcoma patients treated with high-dose intravenous chemotherapy

PURPOSE

Knowledge is limited regarding the prevalence and persistence of chemotherapy-induced leukoencephalopathy in childhood sarcoma patients. This study explored the presence, clinical relevance, and potential risk factors of leukoencephalopathy in childhood bone and soft tissue sarcoma survivors, treated with intravenous chemotherapy.

METHODS

We acquired cross-sectional neurocognitive data in adult survivors (n = 34) (median age at diagnosis [AaD] = 13.32 years, age range = 16-35 years) and healthy age-matched controls (n = 34). Additionally, magnetic resonance imaging included T2-weighted FLAIR (leukoencephalopathy Fazekas rating), multiexponential T2 relaxation (MET2), and multishell diffusion MRI to estimate myelin integrity-related metrics and fluid movement restrictions. Finally, chemotherapy subgroups (methotrexate, alkylating agents, or combination), AaD, and Apoε and MTHFRC677T polymorphisms were explored as potential risk factors for leukoencephalopathy.

RESULTS

At the group level, quality of life, working memory, processing speed, and visual memory were significantly lower in patients compared to controls. Furthermore, long-term leukoencephalopathy was observed in 27.2% of the childhood sarcoma survivors, which was related to attentional processing speed. Lesions were related to diffusion-derived, but not to myelin-sensitive metrics. A significant interaction effect between AaD and chemotherapy group demonstrated more lesions in case of high-dose methotrexate (HD-MTX) (F = 3.434, P = .047). However, patients treated with alkylating agents (without HD-MTX) also showed lesions in younger patients. Genetic predictors were nonsignificant.

CONCLUSION AND IMPLICATION

This study suggests long-term leukoencephalopathy with possibly underlying changes in vasculature, inflammation, or axonal injury, but not necessarily long-term demyelination. Such lesions could affect processing speed, and as such long-term daily life functioning of these patients.

Disparities in Neurotoxicity Risk and Outcomes among Pediatric Acute Lymphoblastic Leukemia Patients

Purpose: Methotrexate chemotherapy can be associated with neurologic complications during therapy and long-term neurologic deficits. This study evaluated demographic and clinical factors associated with incidence of methotrexate neurotoxicity and described the impact of neurotoxicity on acute lymphoblastic leukemia (ALL) therapy in pediatric patients.Experimental Design: Patients were enrolled between 2012 and 2017 from three pediatric cancer treatment centers in the United States. Medical records for suspected cases of methotrexate neurotoxicity, defined as an acute neurologic event following methotrexate therapy, were reviewed. Cox proportional hazards models were used to estimate the association between race/ethnicity and methotrexate neurotoxicity. Multivariable linear regression models compared treatment outcomes between patients with and without methotrexate neurotoxicity.Results: Of the 280 newly diagnosed patients enrolled, 39 patients (13.9%) experienced methotrexate neurotoxicity. Compared with non-Hispanic whites, Hispanic patients experienced the greatest risk of methotrexate neurotoxicity (adjusted HR, 2.43; 95% CI, 1.06-5.58) after accounting for sex, age at diagnosis, BMI Z-score at diagnosis, and ALL risk stratification. Patients who experienced a neurotoxic event received an average of 2.25 fewer doses of intrathecal methotrexate. Six of the 39 cases of neurotoxicity (15.4%) experienced relapse during the study period, compared with 13 of the 241 (2.1%) patients without neurotoxicity (P = 0.0038).Conclusions: Hispanic ethnicity was associated with increased risk of methotrexate neurotoxicity, which was associated with treatment modifications and relapse. Understanding the mechanism and predictors of methotrexate neurotoxicity is important to improving treatment outcomes in pediatric ALL. Clin Cancer Res; 24(20); 5012-7. ©2018 AACR.

Utility and Safety of Intrathecal Methotrexate Treatment in Severe Anti-N-methyl-D-aspartate Receptor Encephalitis: A Pilot Study

Background:

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is a treatable autoimmune neurologic syndrome that occurs with or without tumor association. However, some severe cases are refractory to systemic immunotherapy. This pilot study aimed to evaluate the utility and safety of intrathecal methotrexate injection for severe patients with anti-NMDAR encephalitis who did not respond to first-line immunotherapy.

Methods:

Intrathecal injections with methotrexate and dexamethasone were performed weekly in four legible patients within consecutive 4 weeks. Cerebrospinal fluid (CSF) was collected at baseline and each time of intrathecal injection for identification of anti-NMDAR antibody titers.

Results:

Significant clinical improvement was observed in three patients associated with a stepwise decrease of CSF anti-NMDAR antibody titers (maximum: 1/320 to minimum: 1/10). After 2 months of follow-up, they were able to follow simple commands and had appropriate interactions with people (modified Rankin scale [mRS] of 0–2). At 12 months of follow-up, they all had returned to most activities of daily life (mRS of 0), and no relapses were reported. One patient showed no clinical improvement and died of neurologic complications.

Conclusions:

Intrathecal treatment may be a potentially useful supplementary therapy in severely affected patients with anti-NMDAR encephalitis. Further large cohort study and animal experiment may help us elaborate the utility of intrathecal injection of methotrexate and its mechanism of action.

Health-related quality of life of children on treatment for acute lymphoblastic leukemia: A systematic review

Children with acute lymphoblastic leukemia (ALL) undergo intense anticancer treatment. We systematically reviewed 22 studies evaluating 2,073 ALL patients' health-related quality of life (HRQL) and its clinical/demographic correlates during treatment. Overall HRQL was significantly reduced on treatment. Despite HRQL improvements over time, longitudinal studies reported a proportion of children continued to experience reduced HRQL after treatment completion. We found inconsistent associations between clinical/demographic factors and HRQL outcomes. Tentative evidence emerged for worse HRQL being associated with intensive phases of chemotherapy, corticosteroid therapy, experiencing greater toxicity, older age, and female sex. Longitudinal studies are needed to identify children at-risk of reduced HRQL.

Effect of methotrexate/vitamin B12 on DNA methylation as a potential factor in leukemia treatment-related neurotoxicity

Methotrexate (MTX) is administered to treat childhood acute lymphoblastic leukemia (ALL). It acts by inhibiting dihydrofolate reductase which reduces methyltetrahydrofolate, a key component in one carbon metabolism, thus reducing cell proliferation. Further perturbations to one carbon metabolism, such as reduced vitamin B₁₂ levels via the use of nitrous oxide for sedation during childhood ALL treatment, may increase neurotoxicity risk. With B₁₂ as an enzymatic cofactor, methyltetrahydrofolate is essential to produce methionine, which is critical for DNA methylation. We investigated global and gene specific DNA methylation in neuronal cell lines in response to MTX treatment and vitamin B₁₂ concentration individually, and in combination. Results: MTX treatment alone significantly increased LINE-1 methylation in SH-SY5Y (p = 0.040) and DAOY (p < 0.001), and increased FKBP5 methylation in MO3.13 cells (p = 0.009). Conclusion: We conclude that altered DNA methylation of brain/central nervous system cells could be one mechanism involved in MTX treatment-related neurotoxicities and neurocognitive late effects in ALL survivors.

Neurocognitive outcomes among children who experienced seizures during treatment for acute lymphoblastic leukemia

BACKGROUND

Limited information is available regarding neurocognitive outcomes of children who experience seizures during treatment for acute lymphoblastic leukemia (ALL). Accordingly, the main objectives of this study were to determine the incidence and risk factors for treatment-related seizures among children with ALL, and the neurocognitive outcomes associated with treatment-related seizures.

PROCEDURE

Prospective neuropsychological assessment and magnetic resonance imaging (MRI) were planned for all 498 patients with newly diagnosed ALL enrolled on the St. Jude Total Therapy XV (TOTXV) protocol at three time points. The study database was reviewed retrospectively to identify those with treatment-related seizure. To assess neurocognitive changes associated with seizure, each patient with treatment-related seizure was matched with two cohort patients without seizure for age at treatment, gender, race, and treatment intensity.

RESULTS

Nineteen patients developed seizure, with a 2-year cumulative risk of 3.82 ± 0.86% (SE). No risk factors were identified to be associated with the development of seizure, with a possible exception of intensive chemotherapy used on the standard/high-risk arm as compared to the low-risk arm. Neuropsychological performance of the seizure group, as compared to normative scores and nonseizure control cohort, indicated problems in attention, working memory, and processing speed. Cognitive deficits persisted 2 years after therapy, with additional declines in intellectual function observed. MRI indicated early neurotoxicity among the seizure group, as evidenced by greater leukoencephalopathy on initial examinations.

CONCLUSION

Treatment-related seizures were associated with leukoencephalopathy and decreased neuropsychological performance. Prospective studies are needed to detect changes in neurocognitive status associated with long-term functional impairment.

Posterior reversible encephalopathy syndrome after intrathecal methotrexate infusion: a case report and literature update

Posterior reversible encephalopathy syndrome (PRES) is a rare clinical-radiological entity characterised by seizures, severe headache, mental status instability and visual disturbances. Hypertension is typically present. We report a case of a 13-year old boy with Burkitt lymphoma/leukaemia, who presented with posterior leukoencephalopathy 24 hours after intrathecal methotrexate (MTX) infusion. The child presented with headache, seizures, elevated blood pressure and gradual deterioration of his neurological status. Midazolam, dexamethazone and furosemide were initiated leading to reduction of cerebral oedema and clinical improvement. A thorough literature review is discussed in this report. Pathophysiology of leukoencephalopathy remains unclear. It develops within 5-14 days after intrathecal MTX and resolves within a week usually without permanent neurological sequelae. Broad use of MRI has led to an increasing number of identified cases of PRES. Treatment approach is mainly to manage the underlying cause of PRES. Prognosis is generally benign; however delayed diagnosis and improper management may result in permanent brain insult.

Severe neurotoxicity following intrathecal methotrexate with nitrous oxide sedation in a child with acute lymphoblastic leukemia

Systemic and intrathecal methotrexate is widely used in treatment protocols for childhood acute lymphoblastic leukemia. Its side effects vary in characteristics, intensity and time of onset, and depend on the administration route. Interactions with several drugs are known. Side effects of nitrous oxide sedation, often used for moderately painful procedures, typically occur after long time use and include neurological symptoms. We present a child who experienced a severe and long-lasting neurotoxicity after the third intrathecal application of methotrexate with short sedation by nitrous oxide during induction therapy for acute lymphoblastic leukemia. Symptoms completely resolved after 12 months.

Intrathecal treatment of anti-N-Methyl-D-aspartate receptor encephalitis in children

Anti-NDMA receptor (NMDAR) encephalitis is an auto-immune condition. There is no uniformly agreed treatment strategy for the disorder in children. We report the use of intrathecal treatment with methotrexate and methylprednisolone in three children (one male, two females, age 10y, 11y, and 14y) with anti-NMDAR encephalitis, who did not respond to steroids, plasmapheresis, or rituximab. There was significant clinical improvement and stabilization of the anti-NMDAR antibody titers in cerebrospinal fluid (CSF) and blood in two patients. In the third patient, although anti-NMDAR antibody titers in CSF decreased, clinical recovery was less satisfactory. Intrathecal treatment with methotrexate and methylprednisolone seems to be a promising alternative treatment for some paediatric cases of resistant anti-NMDAR encephalitis.

Methotrexate-induced neurotoxicity and leukoencephalopathy in childhood acute lymphoblastic leukemia

PURPOSE

Methotrexate (MTX) can cause significant clinical neurotoxicity and asymptomatic leukoencephalopathy. We sought to identify clinical, pharmacokinetic, and genetic risk factors for these MTX-related toxicities during childhood acute lymphoblastic leukemia (ALL) therapy and provide data on safety of intrathecal and high-dose MTX rechallenge in patients with neurotoxicity.

PATIENTS AND METHODS

Prospective brain magnetic resonance imaging was performed at four time points for 369 children with ALL treated in a contemporary study that included five courses of high-dose MTX and 13 to 25 doses of triple intrathecal therapy. Logistic regression modeling was used to evaluate clinical and pharmacokinetic factors, and a genome-wide association study (GWAS) was performed to identify germline polymorphisms for their association with neurotoxicities.

RESULTS

Fourteen patients (3.8%) developed MTX-related clinical neurotoxicity. Of 13 patients rechallenged with intrathecal and/or high-dose MTX, 12 did not experience recurrence of neurotoxicity. Leukoencephalopathy was found in 73 (20.6%) of 355 asymptomatic patients and in all symptomatic patients and persisted in 74% of asymptomatic and 58% of symptomatic patients at the end of therapy. A high 42-hour plasma MTX to leucovorin ratio (measure of MTX exposure) was associated with increased risk of leukoencephalopathy in multivariable analysis (P = .038). GWAS revealed polymorphisms in genes enriched for neurodevelopmental pathways with plausible mechanistic roles in neurotoxicity.

CONCLUSION

MTX-related clinical neurotoxicity is transient, and most patients can receive subsequent MTX without recurrence of acute or subacute symptoms. All symptomatic patients and one in five asymptomatic patients develop leukoencephalopathy that can persist until the end of therapy. Polymorphisms in genes related to neurogenesis may contribute to susceptibility to MTX-related neurotoxicity.

Excellent prognosis of late relapses of ETV6/RUNX1-positive childhood acute lymphoblastic leukemia: lessons from the FRALLE 93 protocol

BACKGROUND

The prognosis of patients with relapses of ETV6/RUNX1-positive acute lymphoblastic leukemia remains to be evaluated, particularly with regards to the frequency of late relapses. We performed a long-term, follow-up retrospective study to address the outcome of patients with ETV6/RUNX1-positive leukemia relapses.

DESIGN AND METHODS

Among the 713 children tested for ETV6/RUNX1 enrolled into the FRALLE 93 protocol, 43 ETV6/RUNX1-positive patients relapsed (19.4%). Most were initially stratified in the low or intermediate risk groups. The median follow-up after relapse was 54.2 months. All but three received second-line salvage therapy and 16 underwent allogeneic transplantation.

RESULTS

ETV6/RUNX1 had a strong effect on overall survival after relapse (3-year survival= 64.7% for positive cases versus 46.5% for negative cases) (P=0.007). The 5-year cumulative incidence of relapse was 19.4% and testes were more frequently involved in ETV6/RUNX1-positive relapses (P=0.04). In 81.4% of cases the relapses were late, early combined or isolated extramedullary relapses. The 5-year survival rate of patients with ETV6-RUNX1-positive acute lymphoblastic leukemia relapses reached 80.8% when the relapse occurred after 36 months (versus 31.2% when the relapse occurred earlier). In univariate analysis, female gender was associated with a poor survival, whereas site of relapse, age at diagnosis, leukocytosis and consolidation strategy had no effect. In multivariate analysis, only the duration of first remission remained associated with outcome.

CONCLUSIONS

We found an excellent outcome for patients with ETV6/RUNX1-positive leukemia relapses that occurred more than 36 months after diagnosis. The duration of first complete remission may, therefore, be a guide to define the treatment strategy for patients with relapsed ETV6/RUNX1- positive leukemia.

Guillain-Barré syndrome mimicking acute methotrexate-associated encephalopathy in an adolescent patient with lymphoblastic lymphoma

We describe an adolescent case of Guillain-Barré syndrome (GBS) mimicking acute methotrexate-associated encephalopathy during chemotherapy for lymphoblastic lymphoma. Although initial presentations of hemiparesis and irritability were suggestive of acute encephalopathy, the diminished deep tendon reflexes and subsequent rapid progression to flaccid triparesis with bulbar palsy were consistent with GBS. After the initiation of intravenous immunoglobulin therapy her symptoms improved rapidly, and the diagnosis of GBS was confirmed by nerve conduction studies and cerebrospinal fluid examination in recovery phase. GBS should be considered in the differential diagnosis of acute methotrexate-associated encephalopathy, although GBS is a rare neurologic complication.

[Hemiparesis in acute lymphoblastic leukemia]

The case of an adolescent female patient with acute lymphoblastic leukemia and stroke-like hemiparesis demonstrates a typical manifestation of methotrexate-induced acute encephalopathy. This rare entity occurs both in children and adults and can result from intrathecal as well as high dose intravenous administration of methotrexate. Diagnosis can confidently be made using cerebral MRI including diffusion-weighted imaging (DWI), so that patients can be informed about the favorable prognosis.

Magnetization transfer imaging provides no evidence of demyelination in methotrexate-induced encephalopathy

Subacute MTX-induced encephalopathy is characterized by an abrupt onset of focal neurologic deficits within days after intrathecal or systemic therapy. Demyelination is one proposed mechanism. We describe the neuroimaging features of 2 patients with clinical symptoms of subacute encephalopathy after intrathecal and systemic MTX therapy. DWI showed restricted diffusion, indicating cytotoxic edema. MTI yielded no evidence of demyelination in either patient because there was no loss of MTR in areas of restricted diffusion.

Advances in individual prediction of methotrexate toxicity: a review

As the cure rates for haematological malignancies have improved, the exploration of the balance between efficacy and side effects has become a major research target. The antifolate methotrexate is widely used in the treatment of acute lymphoblastic leukaemia, non-Hodgkin lymphoma, and osteosarcoma. Even when given identical methotrexate doses, patients vary significantly in their response and pattern of toxicities. This diversity can, to some extent, be linked to sequence variations in genes involved in drug absorption, metabolism, excretion, cellular transport, and effector targets or target pathways. In the coming years pharmacogenomics is expected to change our approaches to individualised therapy with methotrexate. However, genetic polymorphisms affect the pharmacokinetics and dynamics of all the drugs a patient receive as well as the normal tissues tolerance to a given drug exposure. Thus, although high-throughput techniques will allow mapping of tens of thousands of genetic polymorphisms in one run, it will be a major challenge to dissect out which of these have the strongest impact on efficacy and toxicity and hence should be the targets for intervention. This paper discusses the pharmacology of methotrexate and reviews studies on haematological malignancies that have attempted to predict the risk of toxicity by specific clinical or genetic features.

Recurrent intrathecal methotrexate induced neurotoxicity in an adolescent with acute lymphoblastic leukemia: Serial clinical and radiologic findings

Systemic and intrathecal methotrexate (MTX) are integral components of acute lymphoblastic leukemia (ALL) therapy, but can be associated with neurotoxicity. We describe here the case of an adolescent male with T-cell ALL who developed recurrent episodes of subacute neurotoxicity characterized by slurred speech, emotional lability, and hemiparesis after intrathecal MTX administration. Serial magnetic resonance imaging with diffusion-weighted imaging showed recurrent areas of restricted diffusion within cerebral hemispheric white matter, which correlated chronologically with the administration of intrathecal therapy and severity of clinical symptoms. Resolution of diffusion abnormalities did not preclude further toxicity and a large lesion could cause persisting symptoms.

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.

Outcomes of a modified CALGB 19802 regimen in adult acute lymphoblastic leukemia

We analyzed the efficacy and toxicity of a modified Cancer and Leukemia Group B (CALGB) 19802 regimen in adult acute lymphoblastic leukemia (ALL). From February 2002 to August 2005, 25 adults with untreated ALL were enrolled in the study. Compared to the original regimen, the modified CALGB 19802 regimen consisted of a 4-drug induction (cyclophosphamide, daunorubicin, vincristine, and prednisone) instead of a 5-drug induction (L-asparaginase was added to the previous regimen). This was followed by high-dose methotrexate (1,000 mg/m(2) x 3 days) and cytarabine (2,000 mg/m(2) x 4 days) for the consolidation cycles. High-dose systemic and intrathecal methotrexate was given for central nervous system prophylaxis. Twenty-three patients (92%) achieved a complete remission (CR), and two patients (8%) had refractory disease. With a median follow-up of 21.5 months, 10 patients (40%) were alive and continued to be in CR. The 3-yr probability of an event-free survival and the overall survival were 39.0% and 47.4%, respectively. Treatment related mortality and major grade 3 to 4 neurotoxicity occurred in 1 patient and 3 patients, respectively. The modified CALGB 19802 regimen demonstrated a high remission rate and a favorable survival rate.