Proton magnetic resonance spectroscopy ((1)H-MRS) of the brain following high-dose methotrexate treatment for childhood cancer

Physiological stress reactivity in pediatric cancer survivors treated with chemotherapy

Children who experience early life stress demonstrate changes to their stress responses, which may modulate long-term health. Childhood cancer presents significant stress during diagnosis, treatment, and survivorship. We hypothesized that children who have completed chemotherapy treatment for ALL will demonstrate altered hormone patterns in response to a stressor compared with healthy controls. Twelve pediatric ALL survivors and 12 healthy controls completed the Trier Social Stress Test. Salivary samples, heart rate, and self-report ratings of stress were collected at baseline, pretest, and posttest. Between group comparison showed baseline (interleukin [IL]-8) was significantly higher in the survivor group versus controls (survivors: 89.9, 40.1-544.9 pg ml^-1 ; controls: 30.7, 5.6-241.9 pg ml^-1 , p = .001) as was peak (IL-8) (survivors: 147.1, 71.6-1177.6 pg ml^-1 ; controls: 75.5, 28.6-698.6 pg ml^-1 ). Peak salivary alpha-amylase (sAA) concentration was significantly lower in the survivor group (survivors: 69.3, 19.4-195.5 U ml^-1 ; controls: 91.2, 27.7-213.7 U ml^-1 ; p = .04). Repeated measures ANOVA revealed significant main effects for time on cortisol (F_{(2.35, 50.81)}  = 5.9, p < .01), sAA (F_{(1.56, 33.17)}  = 6.6, p < .01), stress ratings (F_{(3.42, 88.14)}  = 53.4, p < .001), and heart rate (F_{(8, 83)}  = 16.8, p < .05). Significant main effects for group were observed for IL-8 (F_{(1, 23)}  = 8.2, p < .01) and tumor necrosis factor-α (F_{(1, 23)}  = 6.8, p < .05). Significant interaction effects for group × time were found for sAA (F_{(5, 106)}  = 2.8, p < .05). Our results indicate that childhood ALL survivors have similar responses to stress as healthy controls, but lower sympatho-adrenal-medullary reactivity. Therefore, altered stress regulation may present a pathway modulating long-term health in this population.

A systematic review on the use of quantitative imaging to detect cancer therapy adverse effects in normal-appearing brain tissue

Cancer therapy for both central nervous system (CNS) and non-CNS tumors has been previously associated with transient and long-term cognitive deterioration, commonly referred to as 'chemo fog'. This therapy-related damage to otherwise normal-appearing brain tissue is reported using post-mortem neuropathological analysis. Although the literature on monitoring therapy effects on structural magnetic resonance imaging (MRI) is well established, such macroscopic structural changes appear relatively late and irreversible. Early quantitative MRI biomarkers of therapy-induced damage would potentially permit taking these treatment side effects into account, paving the way towards a more personalized treatment planning.This systematic review (PROSPERO number 224196) provides an overview of quantitative tomographic imaging methods, potentially identifying the adverse side effects of cancer therapy in normal-appearing brain tissue. Seventy studies were obtained from the MEDLINE and Web of Science databases. Studies reporting changes in normal-appearing brain tissue using MRI, PET, or SPECT quantitative biomarkers, related to radio-, chemo-, immuno-, or hormone therapy for any kind of solid, cystic, or liquid tumor were included. The main findings of the reviewed studies were summarized, providing also the risk of bias of each study assessed using a modified QUADAS-2 tool. For each imaging method, this review provides the methodological background, and the benefits and shortcomings of each method from the imaging perspective. Finally, a set of recommendations is proposed to support future research.

The Psychoneuroimmunology of Stress Regulation in Pediatric Cancer Patients

Stress is a ubiquitous experience that can be adaptive or maladaptive. Physiological stress regulation, or allostasis, can be disrupted at any point along the regulatory pathway resulting in adverse effects for the individual. Children with cancer exhibit significant changes to these pathways in line with stress dysregulation and long-term effects similar to those observed in other early-life stress populations, which are thought to be, in part, a result of cytotoxic cancer treatments. Children with cancer may have disruption to several steps in the stress-regulatory pathway including cognitive-affective function, neurological disruption to stress regulatory brain regions, altered adrenal and endocrine function, and disrupted tissue integrity, as well as lower engagement in positive coping behaviours such as physical activity and pro-social habits. To date, there has been minimal study of stress reactivity patterns in childhood illness populations. Nor has the role of stress regulation in long-term health and function been elucidated. We conclude that consideration of stress regulation in childhood cancer may be crucial in understanding and treating the disease.

Alternating hemiparesis and orolingual apraxia as manifestations of methotrexate neurotoxicity in a paediatric case of acute lymphoblastic leukaemia

A 15-year-old girl with a recent diagnosis of acute lymphoblastic leukaemia was admitted to hospital with pancytopaenia after having received high-dose intrathecal methotrexate 1 day prior. During the next week she had intermittent episodes of alternating hemiparesis associated with speech arrest lasting minutes to hours at a time. The episodes were not associated with altered level of consciousness or headache. MRI of the brain showed features consistent with methotrexate encephalopathy. This report discusses the typical clinical and radiological features of methotrexate neurotoxicity in addition to differential diagnoses and the proposed pathophysiological mechanisms.

Mathematics intervention for prevention of neurocognitive deficits in childhood leukemia

BACKGROUND

Despite evidence that CNS treatment is associated with cognitive and academic impairment, interventions to prevent or mitigate these problems are limited. The purpose was to determine if early intervention can prevent declines in mathematics abilities.

PROCEDURES

Fifty-seven children with ALL were enrolled and randomized to a Mathematics Intervention or Standard Care. Subjects completed neurocognitive assessments prior to the intervention, post-intervention, and 1 year later. Parents received written results and recommendations for use with their school. The Mathematics Intervention was based on Multiple Representation Theory and delivered individually over 1 year.

RESULTS

Thirty-two of 57 subjects completed the study and were included in data analyses. These 32 subjects completed all neurocognitive assessments and, for those in the Intervention Group, 40-50 hours of the Mathematics Intervention. There were no group differences on relevant demographic variables; risk stratification; number of intrathecal methotrexate injections; or high dose systemic methotrexate. Significant improvements in calculation and applied mathematics from Baseline to Post-Intervention (P = 0.003 and 0.002, respectively) and in visual working memory from Baseline to 1 year Follow-up (P = 0.02) were observed in the Intervention but not the Standard Care Group. Results from repeated measures ANOVA demonstrated significant between group differences for applied mathematics [F(2,29) = 12.47, P < 0.001] and visual working memory [F(2,29) = 5.53, P = 0.009].

CONCLUSIONS

The Mathematics Intervention improved mathematics abilities and visual working memory compared to standard care. Future studies are needed to translate the Mathematics Intervention into a "virtual" delivery method more readily available to parents and children.

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.

Brain involvement in rheumatoid arthritis: a magnetic resonance spectroscopy study

OBJECTIVE

Tumor necrosis factor alpha was recently implicated as an important mediator of communication between the peripheral and cerebral immune systems in an animal model of chronic inflammation. The purpose of this study was to examine by proton magnetic resonance spectroscopy ((1)H-MRS) the influence of inflammation on cerebral metabolism in patients with rheumatoid arthritis (RA).

METHODS

Single-voxel (1)H-MRS of the centrum semiovale was performed on 35 RA patients (6 men and 29 women; mean +/- SD age 51.8 +/- 14.6 years) and 28 healthy age- and sex-matched control subjects (9 men and 19 women; mean +/- SD age 50.2 +/- 10.4 years). None of the study subjects had any neurologic signs or symptoms. Clinical markers of disease activity were correlated with the (1)H-MRS findings.

RESULTS

Patients with active RA, as reflected by an elevated erythrocyte sedimentation rate (ESR), had a significantly higher ratio of choline to creatine and a significantly lower ratio of N-acetylaspartate to choline than did patients with inactive RA, as reflected by a normal ESR. Moreover, the ratios of choline to creatine and NAA to choline were significantly correlated with the ESR after correction for age, sex, smoking status, handedness, alcohol consumption, medication use, and disease duration. Medication use had no additional effect on these associations.

CONCLUSION

Our data show that systemic inflammation in RA is associated with metabolic changes in the brain.

[Neurotoxicity during induction treatment of childhood acute lymphoblastic leukaemia--two case reports]

INTRODUCTION

During chemotherapy of acute lymphoblastic leukaemia (ALL), children sometimes exhibit neurological disturbances. Chemiotherapeutic regimens include methotrexate, administered either intravenously or via intrathecal route. Although multiple drugs are used in addition to methotrexate, the acute neurotoxicity reported in patients is usually attributed to methotrexate. The acute neurotoxicity usually results in stroke-like symptoms such as aphasia, weakness, sensory deficits, ataxia and seizures.

OUTLINE OF CASES

From 2002 until January 2008, 32 children with ALL were diagnosed and treated at the Children's Hospital in Nis. The patients' age ranged from 1.5 to 16 years. They were treated in accordance with the protocol ALL IC-BFM 2002 (ALL Intercontinental Berlin Frankfurt Münster 2002). Two of the patients (6.25%) exhibited neurotoxicity. After the occurrence of neurological symptoms, the patients were ophthalmologically and neurologically examined. In addition, the magnetic resonance (MR) imaging, computerized tomography and electroencephalography were applied. The paper presents two patients, aged 9 and 15 years respectively, who exhibited acute neurotoxicity--methotrexate encephalopathy during ALL treatment. Both patients had tonic-clonic seizures and neurological symptoms in the course of the induction therapy. Neurotoxicity occurred 7 days after the third, and 3 days after the fourth intrathecal methotrexate therapy. MR images confirmed multi-focal morphological changes of brain density in one of the patients, while the other patient had normal CT reading. Even though the development significantly differed, the changes were reversible in both patients.

CONCLUSION

The neurotoxicity in patients with ALL can be combined with significant structural changes of the brain, but also morphological changes can be absent. Several questions concerning aetiology and treatment of neurological events are raised.

Detection and characterization of neurotoxicity in cancer patients using proton MR spectroscopy

OBJECTIVE

The study objective was to detect abnormalities and identify relationships between brain metabolic ratios determined by proton magnetic resonance spectroscopic imaging ((1)H-MRSI) and neuropsychological (NP) function in cancer patients at risk for neurotoxicity.

METHODS

Thirty-two patients received (1)H-MRSI using a multi-slice, multi-voxel technique on a 1.5T magnet. Cho/NAA, NAA/Cr, and Cho/Cr ratios were identified in seven pre-determined sites without tumor involvement. A battery of age-appropriate NP tests was administered within 7 days of imaging. Relationships were examined between test scores and metabolite ratios.

CONCLUSIONS

This study identifies relationships between brain metabolite ratios and cognitive functioning in cancer patients. (1)H-MRSI may be useful in early detection of neurotoxic effects, but prospective longitudinal studies in a homogeneous population are recommended to determine the prognostic value.

Reduced frontal white matter volume in long-term childhood leukemia survivors: a voxel-based morphometry study

BACKGROUND AND PURPOSE

To our knowledge, no published studies have examined whole-brain regional differences to identify more discrete volumetric changes in the brains of childhood leukemia survivors. We used voxel-based morphometry (VBM) to examine regional gray and white matter differences in a group of long-term survivors of acute lymphoblastic leukemia (ALL) compared with a group of healthy controls. Differences in regional white matter volume were expected, given previous reports of white matter changes during treatment for ALL and reduced brain white matter volumes in long-term survivors. Follow-up analyses examined the relationship of regional brain volumes to cognitive function.

MATERIALS AND METHODS

We compared 9 long-term survivors of ALL with 14 healthy controls. Survivors of ALL were treated with systemic and intrathecal chemotherapy only. T1-weighted axial 3D spoiled gradient high-resolution images collected on a 1.5T MR imaging scanner were used for the VBM analysis. Neuropsychological evaluations were conducted within 2 months of the MR imaging to assess cognitive function.

RESULTS

VBM analysis revealed 2 specific regions of reduced white matter in the right frontal lobes of survivors of ALL compared with healthy controls. Survivors of ALL had lower performances on tests of attention, visual-constructional skills, mental flexibility, and math achievement compared with healthy individuals. Decreased performance on neuropsychological measures was associated with decreased regional white matter volumes. No differences were found between the groups with respect to gray matter regions.

CONCLUSION

These findings are consistent with previous literature describing the long-term cognitive, academic, and imaging findings of survivors of ALL and suggest that right frontal white matter is particularly vulnerable to disruption following intensive chemotherapy for ALL. Future studies should focus on further clarifying the white matter changes observed.

Longitudinal evaluation of fine motor skills in children with leukemia

BACKGROUND

Improved survival for children with acute lymphocytic leukemia (ALL) has allowed investigators to focus on the adverse or side effects of treatment and to develop interventions that promote cure while decreasing the long-term effects of therapy. Although much attention has been given to the significant neurocognitive sequelae that can occur after ALL therapy, limited investigation is found addressing fine motor function in these children and motor function that may contribute to neurocognitive deficits in ALL survivors.

METHODS

Fine motor and sensory-perceptual performances were examined in 82 children with ALL within 6-months of diagnosis and annually for 2 years (year 1 and year 2, respectively) during therapy.

RESULTS

Purdue Pegboard assessments indicated significant slowing of fine motor speed and dexterity for the dominant hand, nondominant hand, and both hands simultaneously for children in this study. Mean Visual-Motor Integration (VMI) scores for children with low-risk and high-risk ALL decreased from the first evaluation to year 1 and again at year 2. Mean VMI scores for children with standard risk ALL increased from the first evaluation to year 1 and then decreased at year 2. Significant positive correlations were found between the Purdue and the VMI at both year 1 and year 2, suggesting that the Pegboard performance consistently predicts the later decline in visual-motor integration. Significant correlations were found between the Purdue Pegboard at baseline and the Performance IQ during year 1, though less consistently during year 2. A similar pattern was also observed between the baseline Pegboard performance and performance on the Coding and Symbol Search subtests during year 1 and year 2.

CONCLUSIONS

In this study, children with ALL experienced significant and persistent visual-motor problems throughout therapy. These problems continued during the first and second years of treatment. These basic processing skills are necessary to the development of higher-level cognitive abilities, including nonverbal intelligence and academic achievement, particularly in arithmetic and written language.

Magnetic resonance spectroscopy (MRS) in the investigation of cancer at The Royal Marsden Hospital and The Institute of Cancer Research

Developments in magnetic resonance spectroscopy (MRS) at The Royal Marsden Hospital and The Institute of Cancer Research are reviewed in the context of preceding developments in nuclear magnetic resonance (NMR) and MRS, and some of the early developments in this field, particularly those leading to human measurements. The early development of technology, and associated techniques for human measurement and assessment will be discussed, with particular reference to experience at out institutions. Applications using particular nuclei will then be described and related to other experimental work where appropriate. Contributions to the development of MRS that have been published in Physics in Medicine and Biology will be discussed.

Short-echo time proton MR spectroscopy in the presence of gadolinium

PURPOSE

The purpose of this work was to quantify the impact of contrast agents on short-TE single-voxel 1H MR spectroscopy (MRS) diagnosis of recurrent brain tumors.

METHOD

Short-TE 1H MRS was performed in 49 patients with biopsy-proven brain tumors and 14 control subjects. Eight patients (nine paired exams) were examined before and after administration of Gd-DTPA (interval approximately 5-7 min).

RESULTS

Tumor spectra showed increased choline/creatine ratio (Cho/Cr; p < 0.009) and Cho concentrations (p < 0.02). Receiver operator characteristic for Cho/Cr = 0.93 differentiated 100% of tumors from control in the absence or presence of contrast agent. Repeated 1H MRS varied <3%. Cho T2 was significantly longer than Cr T2 (p < 0.02).

CONCLUSION

Proton MRS with TE of 30 ms may safely be used in combined contrast-enhanced MRI/MRS protocols. Further study is required with long-TE MRS because of the prolonged T2 of Cho.