Vincristine therapy for children with acute lymphoblastic leukemia impairs conduction in the entire peripheral nerve

Screening for Chemotherapy-induced Peripheral Neuropathy and Utilization of Physical Therapy in Pediatric Patients Receiving Treatment for Hematologic Malignancies

Physical therapy (PT) has been shown to be a helpful intervention in the treatment of chemotherapy-induced peripheral neuropathy (CIPN). Our aim was to screen for CIPN in patients with hematologic malignancies receiving vincristine chemotherapy and obtain a baseline assessment on the percentage of patients utilizing PT in the treatment of CIPN. A retrospective review of surveys administered to parents and patients regarding the severity of peripheral neuropathy symptoms from October 2016 through March 2018 was conducted. Of 116 patients, a total of 102 patients (67 male and 35 female; 4 to 10 y of age, N=63; 11 to 15 y of age, N=19; 16 to 20 y of age, N=20) were eligible for the study, with 67.6% (N=69) reporting symptoms of CIPN. Of these patients, 16.7% scored 4 or greater on the surveys, suggesting clinically severe CIPN. Common parental concerns included decreased strength, difficulty walking up stairs, tripping, and foot drops. Approximately 55.1% of the 69 patients who reported CIPN symptoms were referred to outpatient PT, while 44.9% were not referred. A simple survey consisting of 4 questions that only took several minutes to administer was capable of identifying CIPN in 67.6% of patients receiving vincristine chemotherapy.

Vincristine-Induced Peripheral Neuropathy in Childhood Acute Lymphoblastic Leukemia: Genetic Variation as a Potential Risk Factor

Vincristine (VCR) is the first-line chemotherapeutic medication often co-administered with other drugs to treat childhood acute lymphoblastic leukemia. Dose-dependent neurotoxicity is the main factor restricting VCR’s clinical application. VCR-induced peripheral neuropathy (VIPN) sometimes results in dose reduction or omission, leading to clinical complications or affecting the patient’s quality of life. With regard to the genetic basis of drug responses, preemptive pharmacogenomic testing and simultaneous blood level monitoring could be helpful for the transformation of various findings into individualized therapies. In this review, we discussed the potential associations between genetic variants in genes contributing to the pharmacokinetics/pharmacodynamics of VCR and VIPN incidence and severity in patients with acute lymphoblastic leukemia. Of note, genetic variants in the CEP72 gene have great potential to be translated into clinical practice. Such a genetic biomarker may help clinicians diagnose VIPN earlier. Besides, genetic variants in other genes, such as CYP3A5, ABCB1, ABCC1, ABCC2, TTPA, ACTG1, CAPG, SYNE2, SLC5A7, COCH, and MRPL47, have been reported to be associated with the VIPN, but more evidence is needed to validate the findings in the future. In fact, a variety of complex factors jointly determine the VIPN. In implementing precision medicine, the combination of genetic, environmental, and personal variables, along with therapeutic drug monitoring, will allow for a better understanding of the mechanisms of VIPN, improving the effectiveness of VCR treatment, reducing adverse reactions, and improving patients’ quality of life.

Oncological Children and Well-Being: Occupational Performance and HRQOL Change after Fine Motor Skills Stimulation Activities

Cancer children experience long periods of hospitalization, which are associated with limited performance in several developmental domains and participation restrictions in age appropriate occupations. Fine motor abilities represent building blocks in performing daily life skills and have been found to be closely connected with later academic success. Moreover, medical and psychological sequelae for cancer inpatients may result in diminished daily activities functioning, poor perceived health related quality of life (HRQOL), and increase the likelihood of long-term impairments. This study examines the variations in the occupational performance of children hospitalized for acute lymphoblastic leukemia (ALL) after their participation to a stimulation program designed to enhance fine motor skills. Parents reported significant gains in children's motor functioning, a slight improvement in overall occupational performance related to an increase in the area of productivity and self-care, and a better quality of life perception following the stimulation activities. Feasibility of the stimulation program in a health care setting are discussed evaluating its benefits for cancer children and their families.

Motor and Basic Cognitive Functions in Children with Acute Lymphoblastic Leukemia Undergoing Induction or Consolidation Chemotherapy

Children with acute leukemia (ALL) often suffer from several disease and treatment related side-effects during treatment. The aim of the present study was to determine the gross and fine motor functioning and basic cognitive performance of children (n = 25) with ALL who were undergoing induction or consolidation chemotherapy and to compare these characteristics to a normative group (n = 21) of age-matched typically developing children. We assessed the children's motor functions with the Bruininks-Oseretsky Test of Motor Proficiency Second Edition-Short Form and the Nine-hole Peg Test, and we used the Modified Mini-Mental State Exam (MMSE) to evaluate their cognitive performance. Compared to the normative group, children with ALL had lower scores on total motor proficiency and sub-tests scores of motor functions (p < .05), and on the Nine-hole Peg Test performance (p < .05); but their cognitive performance on the MMSE was not significantly different. Children with ALL would likely benefit from structured exercise and rehabilitative interventions during chemotherapy to prevent and/or ameliorate ALL-related motor dysfunction. We also suggest that their cognitive functioning should be further investigated with more extensive well-validated neurocognitive tests for children (e.g., the Wechsler intelligence scales).

Clinical utility of complex assessment with evoked potentials in acute lymphoblastic leukemia survivors: comparison of various treatment protocols

BACKGROUND

One of the greatest success of pediatric hematology is a prominent improvement of survival in acute lymphoblastic leukemia (ALL). Therefore, special attention needs to be paid to long-term side effects of the treatment such as neurotoxicity. One of the few diagnostic methods that allow an objective assessment of sensory systems are evoked potentials (EP).

METHODS

The analyzed group consisted of 167 ALL long-term survivors, aged 4.9-28.4 years, without auditory, visual and sensory deviations. Patients were treated with New York (NY, n = 35), previous modified Berlin-Frankfurt-Münster (pBFM, n = 47) and BFM95 (n = 85) protocols. In order to assess the impact of radiotherapy on recorded EP, a joint analysis of NY and pBFM groups was performed. The control group consisted of 35 patients, aged 6-17 years. The analyzed patients underwent a complex assessment with visual EP (VEP), somatosensory EP (SEP) and brainstem auditory EP (BAEP) in accordance with current standards.

RESULTS

ALL treatment contributed to the shortening of wave I latency (1.59 vs 1.90, P = 0.003) and prolongation of I-III (2.23 vs 2.04, P = 0.004) and I-V (4.57 vs 4.24, P = 0.002) interwave latencies of BAEP. A significant effect was also noticed in P100 (106.32 vs 101.57, P < 0.001) and N135 (151.42 vs 138.22, P < 0.001) latencies of VEP and N18 amplitude (3.24 vs 4.70, P = 0.007) and P25 latency (21.32 vs 23.39, P < 0.001) of SEP. The distribution of abnormalities between protocols was similar in BAEP (NY - 68.6%, pBFM - 61.7%, BFM95-69.4%, P = 0.650), VEP (NY - 68.6%, pBFM - 42.5%, BFM95-58.3%, P = 0.053) and significantly different for SEP (NY - 62.9%, pBFM - 36.2%, BFM95-53.0%, P = 0.045). The harmful effect of radiotherapy was most clearly marked in numerous disturbances of SEP parameters.

CONCLUSIONS

The presented analysis indicates a high frequency of subclinical abnormalities in EP regardless of the analyzed protocol. To our knowledge current study is the largest and one of the most complex research examining the role of EP in ALL patients. The obtained results indicate the possibility of using a single, objective and non-invasive measurement of EP in ALL survivors in order to stratify the risk of developing sensory abnormalities in adulthood.

Neuromuscular mechanisms that contribute to gross motor performance in survivors of childhood acute lymphoblastic leukemia

PURPOSE

This study explored neuromuscular mechanisms and clinical measures that contribute to countermovement jump performance in survivors of childhood acute lymphoblastic leukemia (ALL CCS) compared to age- and sex-matched peers.

METHODS

This exploratory cross-sectional observational study examined 12 participants, six ALL CCS and six age- and sex-matched peers (7-16 years). During a countermovement jump, rates of muscle activation of lower leg muscles were measured with electromyography, and joint torques and peak jump height with force plates and a motion capture system. Clinical measures included muscle extensibility, balance, and mobility measured by active ankle dorsiflexion, Bruininks-Oseretsky Motor Proficiency (BOT-2), and Timed Up and Go (TUG) tests.

RESULTS

Compared to peers, ALL CCS demonstrated reduced gastrocnemius muscle extensibility and tibialis anterior rate of muscle activation, decreased jump height, and poorer performance on the BOT-2 and TUG. Jump height was significantly correlated with clinical measures of the BOT-2 and TUG.

CONCLUSION

These ALL CCS demonstrated neuromuscular impairments that may impact jump performance, an essential childhood physical activity. Further research is needed to explore intervention strategies to improve the neuromuscular mechanisms that contribute to high-level gross motor skills in ALL CCS.

N-alkylisatin-based microtubule destabilizers bind to the colchicine site on tubulin and retain efficacy in drug resistant acute lymphoblastic leukemia cell lines with less in vitro neurotoxicity

BACKGROUND

Drug resistance and chemotherapy-induced peripheral neuropathy continue to be significant problems in the successful treatment of acute lymphoblastic leukemia (ALL). 5,7-Dibromo-N-alkylisatins, a class of potent microtubule destabilizers, are a promising alternative to traditionally used antimitotics with previous demonstrated efficacy against solid tumours in vivo and ability to overcome P-glycoprotein (P-gp) mediated drug resistance in lymphoma and sarcoma cell lines in vitro. In this study, three di-brominated N-alkylisatins were assessed for their ability to retain potency in vincristine (VCR) and 2-methoxyestradiol (2ME2) resistant ALL cell lines. For the first time, in vitro neurotoxicity was also investigated in order to establish their suitability as candidate drugs for future use in ALL treatment.

METHODS

Vincristine resistant (CEM-VCR R) and 2-methoxyestradiol resistant (CEM/2ME2-28.8R) ALL cell lines were used to investigate the ability of N-alkylisatins to overcome chemoresistance. Interaction of N-alkylisatins with tubulin at the the colchicine-binding site was studied by competitive assay using the fluorescent colchicine analogue MTC. Human neuroblastoma SH-SY5Y cells differentiated into a morphological and functional dopaminergic-like neurotransmitter phenotype were used for neurotoxicity and neurofunctional assays. Two-way ANOVA followed by a Tukey's post hoc test or a two-tailed paired t test was used to determine statistical significance.

RESULTS

CEM-VCR R and CEM/2ME2-28.8R cells displayed resistance indices of > 100 to VCR and 2-ME2, respectively. CEM-VCR R cells additionally displayed a multi-drug resistant phenotype with significant cross resistance to vinblastine, 2ME2, colchicine and paclitaxel consistent with P-gp overexpression. Despite differences in resistance mechanisms observed between the two cell lines, the N-alkylisatins displayed bioequivalent dose-dependent cytotoxicity to that of the parental control cell line. The N-alkylisatins proved to be significantly less neurotoxic towards differentiated SH-SY5Y cells than VCR and vinblastine, evidenced by increased neurite length and number of neurite branch points. Neuronal cells treated with 5,7-dibromo-N-(p-hydroxymethylbenzyl)isatin showed significantly higher voltage-gated sodium channel function than those treated with Vinca alkaloids, strongly supportive of continued action potential firing.

CONCLUSIONS

The N-alkylisatins are able to retain cytotoxicity towards ALL cell lines with functionally distinct drug resistance mechanisms and show potential for reduced neurotoxicity. As such they pose as promising candidates for future implementation into anticancer regimes for ALL. Further in vivo studies are therefore warranted.

Measuring vincristine-induced peripheral neuropathy in children with cancer: validation of the Dutch pediatric-modified Total Neuropathy Score

Purpose

The aims were to evaluate the construct validity and reliability of the Dutch version of the pediatric-modified Total Neuropathy Score (ped-mTNS) for assessing vincristine-induced peripheral neuropathy (VIPN) in Dutch pediatric oncology patients aged 5–18 years.

Methods

Construct validity (primary aim) of the ped-mTNS was determined by testing hypotheses about expected correlation between scores of the ped-mTNS (range: 0–32) and the Common Terminology Criteria for Adverse Events (CTCAE) (range: 0–18) for patients and healthy controls and by comparing patients and controls regarding their total ped-mTNS scores and the proportion of children identified with VIPN. Inter-rater and intra-rater reliability and measurement error (secondary aims) were assessed in a subgroup of study participants.

Results

Among the 112 children (56 patients and 56 age- and gender-matched healthy controls) evaluated, correlation between CTCAE and ped-mTNS scores was as expected (moderate (r = 0.60)). Moreover, as expected, patients had significantly higher ped-mTNS scores and more frequent symptoms of VIPN compared with controls (both p < .001). Reliability as measured within the intra-rater group (n = 10) (intra-class correlation coefficient (ICC_agreement) = 0.64, standard error of measurement (SEM_agreement) = 2.92, and smallest detectable change (SDC_agreement) = 8.1) and within the inter-rater subgroup (n = 10) (ICC_agreement = 0.63, SEM_agreement = 3.7, and SDC_agreement = 10.26) indicates insufficient reliability.

Conclusion

The Dutch version of the ped-mTNS appears to have good construct validity for assessing VIPN in a Dutch pediatric oncology population, whereas reliability appears to be insufficient and measurement error high. To improve standardization of VIPN assessment in children, future research aimed at evaluating and further optimizing the psychometric characteristics of the ped-mTNS is needed.

Electronic supplementary material

The online version of this article (10.1007/s00520-019-05106-3) contains supplementary material, which is available to authorized users.

Neonatal vincristine administration modulates intrinsic neuronal excitability in the rat dorsal root ganglion and spinal dorsal horn during adolescence

Our recent work has shown that the early-life administration of vincristine (VNC), commonly used to treat pediatric cancers, evokes mechanical pain hypersensitivity in rats that emerges during adolescence and persists into adulthood. However, the underlying mechanisms remain unclear, as nothing is known about how neonatal VNC treatment influences peripheral and central nociceptive processing at the cellular level. Here, we used in vitro intracellular microelectrode and whole-cell patch-clamp recordings to evaluate the consequences of early-life VNC administration on the intrinsic membrane properties of adolescent dorsal root ganglion and spinal superficial dorsal horn neurons. The results demonstrate that VNC treatment increased the prevalence and rate of repetitive firing in both large- and medium-diameter sensory neurons, while reducing repetitive firing in small-diameter neurons, in comparison with vehicle-treated littermate controls. By contrast, passive membrane properties and peripheral conduction velocities were similar between experimental groups across all classes of primary afferents. Within the adolescent superficial dorsal horn, neonatal VNC exposure significantly enhanced the intrinsic membrane excitability of lamina I spinoparabrachial neurons, as evidenced by a decrease in rheobase and elevation of repetitive firing frequency compared with controls. Meanwhile, putative interneurons within lamina I exhibited a reduction in repetitive action potential discharge after early-life chemotherapy. Collectively, these findings suggest that neonatal VNC treatment evokes cell type-specific changes in intrinsic excitability at multiple levels of the ascending pain pathway. Overall, this work lays an essential foundation for the future exploration of the ionic mechanisms that drive chemotherapy-induced chronic pain in children and adolescents.

Pharmacogenomics of Vincristine-Induced Peripheral Neuropathy Implicates Pharmacokinetic and Inherited Neuropathy Genes

Vincristine is an effective chemotherapeutic drug for various cancers, including acute lymphoblastic leukemia (ALL). Unfortunately, clinical utility is restricted by dose‐limiting vincristine‐induced peripheral neuropathies (VIPN). We sought to determine the association of VIPN with a recently identified risk variant, CEP72 rs924607, and drug absorption, distribution, metabolism, and excretion (ADME) gene variants in pediatric ALL. This was followed by a meta‐analysis of pharmacogenomic data from over 500 patients. CEP72 rs924607 was significantly associated with VIPN (P = 0.02; odds ratio (OR) = 3.4). ADME analyses identified associations between VIPN and ABCC1 rs3784867 (P = 5.34 × 10⁻⁵; OR = 4.9), and SLC5A7 rs1013940 (P = 9.00 × 10⁻⁴; OR= 8.6); genes involved in vincristine transport and inherited neuropathies, respectively. Meta‐analysis identified an association with a variant related to TTPA (rs10504361: P = 6.85 × 10⁻⁴; OR = 2.0), a heritable neuropathy‐related gene. This study provides essential corroboratory evidence for CEP72 rs924607 and highlights the importance of drug transporter and inherited neuropathy genes in VIPN.

Peripheral Neuropathy, Sensory Processing, and Balance in Survivors of Acute Lymphoblastic Leukemia

Purpose To compare peripheral nervous system function and balance between adult survivors of childhood acute lymphoblastic leukemia (ALL) and matched controls and to determine associations between peripheral neuropathy (PN) and limitations in static balance, mobility, walking endurance, and quality of life (QoL) among survivors. Patients and Methods Three hundred sixty-five adult survivors of childhood ALL and 365 controls with no cancer history completed assessments of PN (modified Total Neuropathy Score [mTNS]), static balance (Sensory Organization Test [SOT]), mobility (Timed Up and Go), walking endurance (6-minute walk test), QoL (Medical Outcomes Study 36-Item Short Form Survey), and visual-motor processing speed (Wechsler Adult Intelligence Scale). Results PN, but not impairments, in performance on SOT was more common in survivors than controls (41.4% v 9.5%, respectively; P < .001). In multivariable models, higher mTNS scores were associated with longer time to complete the Timed Up and Go (β = 0.15; 95% CI, 0.06 to 0.23; P < .001), shorter distance walked in 6 minutes (β = -4.39; 95% CI, -8.63 to -0.14; P = .04), and reduced QoL (β = -1.33; 95% CI, -1.79 to -0.87; P < .001 for physical functioning; β = -1.16; 95% CI, -1.64 to -0.67; P < .001 for role physical; and β = -0.88; 95% CI, -1.34 to -0.42; P < .001 for general health). Processing speed (β = 1.69; 95% CI, 0.98 to 2.40; P < .001), but not mTNS score, was associated with anterior-posterior sway on the SOT. Conclusion PN in long-term ALL survivors is associated with movement, including mobility and walking endurance, but not with static standing balance. The association between processing speed and sway suggests that static balance impairment in ALL survivors may be influenced by problems with CNS function, including the processing of sensory information.

Early life vincristine exposure evokes mechanical pain hypersensitivity in the developing rat

Vincristine (VNC) is commonly used to treat pediatric cancers, including the most prevalent childhood malignancy, acute lymphoblastic leukemia. Although clinical evidence suggests that VNC causes peripheral neuropathy in children, the degree to which pediatric chemotherapeutic regimens influence pain sensitivity throughout life remains unclear, in part because of the lack of an established animal model of chemotherapy-induced neuropathic pain during early life. Therefore, this study investigated the effects of VNC exposure between postnatal days (P) 11 and 21 on mechanical and thermal pain sensitivity in the developing rat. Low doses of VNC (15 or 30 μg/kg) failed to alter nociceptive withdrawal reflexes at any age examined compared with vehicle-injected littermate controls. Meanwhile, high dose VNC (60 μg/kg) evoked mechanical hypersensitivity in both sexes beginning at P26 that persisted until adulthood and included both static and dynamic mechanical allodynia. Hind paw withdrawal latencies to noxious heat and cold were unaffected by high doses of VNC, suggesting a selective effect of neonatal VNC on mechanical pain sensitivity. Gross and fine motor function appeared normal after VNC treatment, although a small decrease in weight gain was observed. The VNC regimen also produced a significant decrease in intraepidermal nerve fiber density in the hind paw skin by P33. Overall, the present results demonstrate that high-dose administration of VNC during the early postnatal period selectively evokes a mechanical hypersensitivity that is slow to emerge during adolescence, providing further evidence that aberrant sensory input during early life can have prolonged consequences for pain processing.

Modifying bone mineral density, physical function, and quality of life in children with acute lymphoblastic leukemia

BACKGROUND

The early effects of childhood acute lymphoblastic leukemia (ALL) include decreased physical function, bone mineral density (BMD/g/cm2 ), and health-related quality of life (HRQL). We assessed the capacity of a physical therapy and motivation-based intervention, beginning after diagnosis and continuing through the end of treatment, to positively modify these factors.

PROCEDURE

A 2.5-year randomized controlled trial of 73 patients aged 4-18.99 years within 10 days of ALL diagnosis assessed BMD at baseline (T0 ) and end of therapy (T3 ), strength, range of motion, endurance, motor skills, and HRQL at baseline (T0 ), 8 (T1 ), 15 (T2 ), and 135 (T3 ) weeks.

RESULTS

There were no significant changes between groups (intervention, n = 33; usual care, n = 40) in BMD (P = 0.059) at T3 or physical function and HRQL at T0 -T3 . While BMD declined in both the intervention (T0  = -0.21, T3  = -0.55) and usual care (T0  = -0.62, T3  = -0.78) groups, rates of decline did not differ between groups (P = 0.56). Univariate analysis (n = 73) showed associations of higher T3 bone density with body mass index T1 (P = 0.01), T2 (P = <0.0001), T3 (P = 0.01), T3 ankle flexibility/strength (P = 0.001), and T2 parent (P = 0.02)/T0 child (P = 0.03) perceptions of less bodily pain.

CONCLUSIONS

The intervention delivered during treatment was not successful in modifying BMD, physical function, or HRQL. Physical activity, at the level and intensity required to modify these factors, may not be feasible during early treatment owing to the child's responses to the disease and treatment. Future studies will consider intervention implementation during late maintenance therapy, extending into survivorship.

Elevated visual dependency in young adults after chemotherapy in childhood

Chemotherapy in childhood can result in long-term neurophysiological side-effects, which could extend to visual processing, specifically the degree to which a person relies on vision to determine vertical and horizontal (visual dependency). We investigated whether adults treated with chemotherapy in childhood experience elevated visual dependency compared to controls and whether any difference is associated with the age at which subjects were treated. Visual dependency was measured in 23 subjects (mean age 25.3 years) treated in childhood with chemotherapy (CTS) for malignant, solid, non-CNS tumors. We also stratified CTS into two groups: those treated before 12 years of age and those treated from 12 years of age and older. Results were compared to 25 healthy, age-matched controls. The subjective visual horizontal (SVH) and vertical (SVV) orientations was recorded by having subjects position an illuminated rod to their perceived horizontal and vertical with and without a surrounding frame tilted clockwise and counter-clockwise 20° from vertical. There was no significant difference in rod accuracy between any CTS groups and controls without a frame. However, when assessing visual dependency using a frame, CTS in general (p = 0.006) and especially CTS treated before 12 years of age (p = 0.001) tilted the rod significantly further in the direction of the frame compared to controls. Our findings suggest that chemotherapy treatment before 12 years of age is associated with elevated visual dependency compared to controls, implying a visual bias during spatial activities. Clinicians should be aware of symptoms such as visual vertigo in adults treated with chemotherapy in childhood.

Vincristine-induced peripheral neuropathy in children with cancer: A systematic review

Vincristine-induced peripheral neuropathy (VIPN) is a dose-limiting side effect of vincristine (VCR) treatment in children, leading to diminished quality of life. Much remains unknown about the underlying mechanisms of VIPN. This review systematically summarizes the available literature concerning contributing factors of VIPN development in children. Studied factors include patient characteristics, VCR dose, administration method, pharmacokinetics, and genetic factors. Furthermore, this review reports on currently available tools to assess VIPN in children. In total, twenty-eight publications were included. Results indicate that Caucasian race, higher VCR dose, older age and low clearance negatively influence VIPN, although results regarding the latter two factors were rather conflicting. Moreover, genetic pathways influencing VIPN were identified. Furthermore, the studied tools to assess VIPN seriously impairs comparability across study results. Studying the factors and their interactions that seem to influence VIPN in children, should aid in personalized VCR treatment, thereby increasing VCR effectiveness while minimizing toxicity.

Balance in children with acute lymphoblastic leukemia

BACKGROUND

Treatment for acute lymphoblastic leukemia (ALL) can affect balance via different mechanisms, including sensory and motor peripheral neuropathy, cognitive impairment, and reduced muscle strength and flexibility. To provide an overview of what is currently known about the effects of cancer treatment on balance in pediatric ALL patients and survivors, and of the predictors of poor balance, a review of the literature was conducted.

METHODS

Five databases were searched for English-language original research articles on balance during or after treatment for pediatric ALL.

RESULTS

From a total of nine studies, six identified significant balance problems in children with ALL during or after treatment. The percentage of patients or survivors with impaired balance varied between 27% and 69% during treatment, 7% and 65% a few years after completion of treatment, and 14% and 17% many years after the completion of treatment. Factors associated with impaired balance were higher body mass index; higher intrathecal methotrexate dose; cranial radiation; knee extensor weakness; and impaired cognition.

CONCLUSION

Although heterogeneity between the studies regarding patient age; age at diagnosis; time since completion of treatment; and methods of quantifying balance make it difficult to reach a single conclusion, the evidence suggests that survivors may experience short- and/or long-term balance difficulties. While there is a need for additional studies to better understand the effects of impaired balance in survivors, clinicians treating both child and adult survivors of ALL need to be aware of these potential risks.

Decreased postural control in adult survivors of childhood cancer treated with chemotherapy

The objective of cancer treatment is to secure survival. However, as chemotherapeutic agents can affect the central and peripheral nervous systems, patients must undergo a process of central compensation. We explored the effectiveness of this compensation process by measuring postural behaviour in adult survivors of childhood cancer treated with chemotherapy (CTS). We recruited sixteen adults treated with chemotherapy in childhood for malignant solid (non-CNS) tumours and 25 healthy age-matched controls. Subjects performed posturography with eyes open and closed during quiet and perturbed standing. Repeated balance perturbations through calf vibrations were used to study postural adaptation. Subjects were stratified into two groups (treatment before or from 12 years of age) to determine age at treatment effects. Both quiet (p = 0.040) and perturbed standing (p ≤ 0.009) were significantly poorer in CTS compared to controls, particularly with eyes open and among those treated younger. Moreover, CTS had reduced levels of adaptation compared to controls, both with eyes closed and open. Hence, adults treated with chemotherapy for childhood cancer may suffer late effects of poorer postural control manifested as reduced contribution of vision and as reduced adaptation skills. These findings advocate development of chemotherapeutic agents that cause fewer long-term side effects when used for treating children.

Oxidative Stress, Motor Abilities, and Behavioral Adjustment in Children Treated for Acute Lymphoblastic Leukemia

PURPOSE/OBJECTIVES

To examine associations among oxidative stress, fine and visual-motor abilities, and behavioral adjustment in children receiving chemotherapy for acute lymphoblastic leukemia (ALL)
.

DESIGN

A prospective, repeated-measures design
.

SETTING

Two pediatric oncology settings in the southwestern United States.

SAMPLE

89 children with ALL were followed from diagnosis to the end of chemotherapy.

METHODS

Serial cerebrospinal fluid samples were collected during scheduled lumbar punctures and analyzed for oxidative stress biomarkers. Children completed fine motor dexterity, visual processing speed, and visual-motor integration measures at three time points. Parents completed child behavior ratings at the same times.

MAIN RESEARCH VARIABLES

Oxidative stress, fine motor dexterity, visual processing, visual-motor integration, and behavioral adjustment
.

FINDINGS

Children with ALL had below-average fine motor dexterity, visual processing speed, and visual-motor integration following the induction phase of ALL therapy. By end of therapy, visual processing speed normalized, and fine motor dexterity and visual-motor integration remained below average. Oxidative stress measures correlated with fine motor dexterity and visual-motor integration. Decreased motor functioning was associated with increased hyperactivity and anxiety
.

CONCLUSIONS

Oxidative stress occurs following chemo-therapy for childhood ALL and is related to impaired fine motor skills and visual symptoms
.

IMPLICATIONS FOR NURSING

Early intervention should be considered to prevent fine motor and visual-spatial deficits, as well as behavioral problems.

The Association Between Motor Skills and Academic Achievement Among Pediatric Survivors of Acute Lymphoblastic Leukemia

OBJECTIVE

Assess the association between fine motor (FM) and visual-motor integration (VMI) skills and academic achievement in pediatric acute lymphoblastic leukemia (ALL) survivors.

METHODS

In this 28-site cross-sectional study of 256 children in first remission, a mean of 8.9 ± 2.2 years after treatment for standard-risk precursor-B ALL, validated measures of FM, VMI, reading, math, and intelligence were administered at mean follow-up age of 12.8 ± 2.5 years. 

RESULTS

 VMI was significantly associated with written math calculation ability (p < .0069) after adjusting for intelligence (p < .0001). VMI was more strongly associated with math in those with lower intelligence (p = .0141). Word decoding was also significantly associated with VMI but with no effect modification by intelligence. FM skills were not associated with either reading or math achievement.

CONCLUSION

These findings suggest that VMI is associated with aspects of math and reading achievement in leukemia survivors. These skills may be amenable to intervention.

Oculomotor Deficits after Chemotherapy in Childhood

Advances in the diagnosis and treatment of pediatric malignancies have substantially increased the number of childhood cancer survivors. However, reports suggest that some of the chemotherapy agents used for treatment can cross the blood brain barrier which may lead to a host of neurological symptoms including oculomotor dysfunction. Whether chemotherapy at young age causes oculomotor dysfunction later in life is unknown. Oculomotor performance was assessed with traditional and novel methods in 23 adults (mean age 25.3 years, treatment age 10.2 years) treated with chemotherapy for a solid malignant tumor not affecting the central nervous system. Their results were compared to those from 25 healthy, age-matched controls (mean age 25.1 years). Correlation analysis was performed between the subjective symptoms reported by the chemotherapy treated subjects (CTS) and oculomotor performance. In CTS, the temporal control of the smooth pursuit velocity (velocity accuracy) was markedly poorer (p<0.001) and the saccades had disproportionally shorter amplitude than normal for the associated saccade peak velocity (main sequence) (p = 0.004), whereas smooth pursuit and saccade onset times were shorter (p = 0.004) in CTS compared with controls. The CTS treated before 12 years of age manifested more severe oculomotor deficits. CTS frequently reported subjective symptoms of visual disturbances (70%), unsteadiness, light-headedness and that things around them were spinning or moving (87%). Several subjective symptoms were significantly related to deficits in oculomotor performance. To conclude, chemotherapy in childhood or adolescence can result in severe oculomotor dysfunctions in adulthood. The revealed oculomotor dysfunctions were significantly related to the subjects' self-perception of visual disturbances, dizziness, light-headedness and sensing unsteadiness. Assessments of oculomotor function may, thus, offer an objective method to track and rate the level of neurological complications following chemotherapy.

Measuring vincristine-induced peripheral neuropathy in children with acute lymphoblastic leukemia

BACKGROUND

Vincristine-induced peripheral neuropathy (VIPN) is difficult to quantify in children.

OBJECTIVE

The study objective was to examine the reliability, validity, and clinical feasibility of several VIPN measures for use in children with acute lymphoblastic leukemia.

INTERVENTIONS/METHODS

Children (n = 65) aged 1 to 18 years receiving vincristine at 4 academic centers participated in the study. Baseline and pre-vincristine administration VIPN assessments were obtained using the Total Neuropathy Score-Pediatric Vincristine (TNS©-PV), the National Cancer Institute Common Terminology Criteria for Adverse Events, the Balis grading scale, and the FACES Pain Scale. The TNS-PV scores (n = 806) were obtained over 15 weeks. Blood was obtained at several time points to quantify pharmacokinetic parameters.

RESULTS

Cronbach's α for a reduced TNS-PV scale was .84. The TNS-PV scores correlated with cumulative vincristine dosage (r = 0.53, P = 0.01), pharmacokinetic parameters (r = 0.41, P = 0.05), and grading scale scores (r range = 0.46-0.52, P = .01). FACES scores correlated with the TNS-PV neuropathic pain item (r = 0.48; P = .01) and were attainable in all ages. A 2-item V-Rex score (vibration and reflex items) was the most responsive to change (effect size = 0.65, P < 0.001). The TNS-PV scores were attainable in 95% of children 6 years or older.

CONCLUSIONS

The TNS-PV is reliable and valid for measuring VIPN. It is sensitive to change over time (15 weeks) and feasible for use in children 6 years or older.

IMPLICATIONS FOR PRACTICE

The TNS-PV may be a useful tool for assessing vincristine toxicity in children with acute lymphoblastic leukemia.

Blood pressure and body composition in long-term survivors of childhood acute lymphoblastic leukemia

BACKGROUND

Long-term survivors of acute lymphoblastic leukemia (ALL) in childhood are at increased risk of late effects of cancer treatment, among which are cardiovascular sequelae. Purpose of this study was to assess blood pressure and body composition in childhood ALL survivors and compare data to reference values from the general population.

PROCEDURE

This single-center retrospective study included 68 survivors of childhood ALL with a median age of 25 years (range 16.4-39.5) and a median follow-up of 16.0 years (range 5.3-30.4). Data on previous treatment, blood pressure and measurements of weight and height at diagnosis and at long-term follow-up (from which body mass index (BMI) was calculated) were obtained from medical records. All data were converted to control-referenced standard deviation scores.

RESULTS

Of the ALL survivors 48½% were prehypertensive and 22.1% were hypertensive. Both the mean systolic (mean SDS 0.736, P < 0.001) and diastolic blood pressure (mean SDS 0.409, P < 0.001) of survivors was significantly higher compared to reference control values. Based on BMI values, 38.2% of the survivors were considered overweight/obese and females, in contrast to males had a significantly higher BMI (mean SDS 1.355, P < 0.001) compared to reference values. In addition, females who had received cranial radiotherapy (mean SDS 2.078) had a significantly higher BMI than females who had not (mean SDS 0.512) (P = 0.009).

CONCLUSIONS

Both diastolic and systolic blood pressure are significantly increased in survivors of childhood ALL. Female survivors treated with cranial radiation therapy have the highest prevalence and greatest risk of overweight/obesity. Therefore, survivors of childhood ALL are likely to be at an increased risk of cardiovascular disease later in life, which stresses the need for follow-up and adequate medical and/or life style interventions.

Feasibility and parent satisfaction of a physical therapy intervention program for children with acute lymphoblastic leukemia in the first 6 months of medical treatment

BACKGROUND

Children with acute lymphoblastic leukemia (ALL) are at risk for developing musculoskeletal complications during and after their medical treatment. The objective of this study was to examine the feasibility of an in-hospital physical therapy- and home exercise program during the first four phases of medical treatment, for children with newly diagnosed ALL.

PROCEDURE

Nine patients, between the ages of 2-14 years old were enrolled within 2 weeks of diagnosis in the study. Each patient was evaluated at study entry, after each of the first four phases of therapy and each time patients were re-admitted to the hospital. Following the initial physical therapy evaluation an individualized home exercise program was developed, consisting of stretching, strengthening, and aerobic exercises. The following end points were measured at each evaluation: gross motor assessment as measured by gross motor function measure (GMFM), health-related quality of life as measured by the PedsQL and parent satisfaction questionnaire.

RESULTS

This study was feasible with 98% of the evaluation sessions completed. The GMFM and PedsQL improved steadily throughout the study; however, the PedsQL slightly decreased from interim maintenance to delayed intensification. The parents reported being satisfied with the physical therapy program.

CONCLUSION

We demonstrated that an in-hospital- and home exercise physical therapy program during the first four phases of medical treatments is feasible for children with ALL. Future randomized studies are needed to confirm whether an initial physical therapy program at diagnosis in children with ALL will limit functional impairments, improve overall fitness and increase health-related quality of life.

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.

Physician referral frequency for physical therapy in children with acute lymphoblastic leukemia

Children with acute lymphoblastic leukemia (ALL) are at risk for developing musculoskeletal complications. Few studies have examined the role of physical therapy (PT) for addressing these complications. The study objective was to examine why and when in the medical treatment, children with ALL receive a referral to PT. Retrospective chart review of 35 children, diagnosed with ALL in 2006 and 2007 at Penn State Children's Hospital was carried out. A questionnaire was completed by 6 pediatric oncologists, to identify their referral patterns. The chart review demonstrated that 25 of the 35 patients had reports of musculoskeletal complications sometime during their treatment, but only 10 (30%) were referred to PT. The most common reason for referral was decreased functional mobility. Patients were referred evenly through all phases of therapy. Vincristine was reduced in 5 patients, the most common cause being peripheral neuropathy and foot drop. The majority (5/6) of the physicians reported that they "sometimes" refer patients to PT, through different phases of therapy, with 1/3 reporting all phases. The results show that although physicians identified the musculoskeletal complications, only a minority of patients were referred for PT. This supports the need for increasing the awareness of physicians about benefits of early integration of PT into the medical treatment.

Peripheral neuropathy in survivors of childhood acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is the most common form of cancer in children. Recent advances in treatment have led to dramatically improved survival rates. Standard ALL treatment includes multiple administrations of the chemotherapeutic drug vincristine, which is a known neurotoxic agent. Although peripheral neuropathy is a well-known toxicity among children receiving vincristine acutely, the long-term effects on the peripheral nervous system in these children are not clear. The objective of this study was to determine the prevalence of neuropathy and its impact on motor function and quality of life (QOL) among children who survived ALL. Thirty-seven survivors of childhood ALL aged 8-18 underwent evaluation for neuropathy through self-reported symptoms, standardized examinations, and nerve conduction studies (NCS). Functional impact of neuropathy was assessed using the Bruininks-Oseretsky test of Motor Proficiency (BOT-2). QOL was assessed using the PedsQL. Nerve conduction study abnormalities were seen in 29.7% of children who were longer than 2 years off therapy for ALL. Most children with an abnormal examination or NCS did not have subjective symptoms. Although overall motor function was below population norms on the BOT-2, presence of neuropathy did not significantly correlate with motor functional status or QOL.

Polymorphisms in genes involved in vincristine pharmacokinetics or pharmacodynamics are not related to impaired motor performance in children with leukemia

INTRODUCTION

Impaired motor performance in children who completed treatment for acute lymphoblastic leukemia (ALL) may be related to polymorphisms of the metabolising gene CYP3A5 or vincristine toxicity related genes MDR-1 and MAPT.

METHODS

Motor performance was measured with the Movement Assessment Battery for Children (movement-ABC). DNA, from mononuclear blood cells was genotyped for CYP3A5, MDR-1 and MAPT polymorphisms.

RESULTS

Motor performance was not significantly affected by CYP3A5*3/*3 and CYP3A5*1*3 genotypes, MDR-1 polymorphisms or MAPT haplotype.

CONCLUSION

Our data did not show that CYP3A5, MDR-1 or MAPT polymorphisms are linked to impaired motor performance in children after treatment for ALL.

Promoting physical activity in childhood cancer survivors: results from the Childhood Cancer Survivor Study

BACKGROUND

Although physical activity may modify the late effects of childhood cancer treatment, from 20% to 52% of adult survivors are sedentary. The authors of this report sought to identify modifiable factors that influence survivors' participation in physical activity.

METHODS

Structural equation modeling of data were derived from the Childhood Cancer Survivors Study of adult survivors (current mean age, 30.98 years; mean years since diagnosis, 23.74; mean age at diagnosis, 9.25 years) who were diagnosed between 1970 and 1986.

RESULTS

Approximately 40% of the variance in male survivors' recent participation versus nonparticipation in physical activity was explained directly and/or indirectly by self-reported health fears (P = .01), perceived primary-care physician (PCP) expertise (P = .01), baseline exercise frequency (P < or = .001), education level (P = .01), self-reported stamina (P = .01), cancer-related pain (P < or = .001), fatigue (P < or = .001), age at diagnosis (P = .01), cancer-related anxiety (P < or = .001), motivation (P = .01), affect (P = .01), and discussion of subsequent cancer risk with the PCP (P < or = .001) (N = 256; chi-square test statistic = 53.38; degrees of freedom [df] = 51; P = .38, Comparative Fit Index [CFI] = 1.000; Tucker Lewis Index [TLI] = 1.000; root mean square of approximation [RMSEA] = 0.014; weighted root mean square residual [WRMR] = 0.76). Thirty-one percent of the variance in women' recent physical activity participation was explained directly and/or indirectly by self-reported stamina (P < or = .001), fatigue (P = .01), baseline exercise frequency (P = .01), cancer-related pain (P < or = .001), cancer-related anxiety (P = .01), recency of visits with PCP (<0.001), quality of interaction with the PCP (P = .01), and motivation (P < or = .001; N = 366; chi-square test statistic = 67.52; df = 55; P = .12; CFI = 0.98; TLI = 0.98; RMSEA = 0.025; WRMR = 0.76).

CONCLUSIONS

Gender-tailored intervention strategies in which providers specifically target motivation, fear, and affect may support physical activity in childhood cancer survivors.

Neurodevelopmental sequelae of pediatric acute lymphoblastic leukemia and its treatment

This review will describe the neurocognitive outcomes associated with pediatric acute lymphoblastic leukemia (ALL) and its treatment. The literature is reviewed with the aim of addressing methodological issues, treatment factors, risks and moderators, special populations, relationship to neuroimaging findings, and directions for future research. It is concluded that neurocognitive outcomes for the majority of children with standard-risk ALL treated according to current chemotherapy protocols is relatively good, but subgroups of children are more significantly compromised. As medical treatments advance and survival rates continue to improve, neurocognitive outcomes and other quality of life indicators will become increasingly important. Preventing or ameliorating treatment-related neuropsychological sequelae represents the next major challenge in pediatric ALL.

Decrease in peripheral muscle strength and ankle dorsiflexion as long-term side effects of treatment for childhood cancer

BACKGROUND

This study investigated muscle strength, passive ankle dorsiflexion, and their association with motor performance in children after treatment for acute lymphoblastic leukemia, Wilms tumor, B-non-Hodgkin lymphoma, and malignant mesenchymal tumors.

PROCEDURE

Muscle strength was assessed with a hand-held dynamometer and ankle dorsiflexion with a goniometer in 92 and 64 survivors, respectively. Motor performance was measured with the Movement Assessment Battery for Children (movement-ABC). Age at testing: 6.1-12.9 years. Mean time since completing treatment: 3.3 years. Results were compared to 155 healthy controls.

RESULTS

Muscle strength of the survivors was reduced in ankle dorsiflexors on both sides (P < 0.001), wrist dorsiflexors on the non-dominant side (P < 0.001), and pinch grip on the non-dominant (P = 0.001) and dominant side (P = 0.01). Passive ankle dorsiflexion of the survivors was significantly less on both sides (P < 0.01). Movement-ABC percentile score was affected by pinch grip strength on the non-dominant (P < 0.004), and dominant side (P = 0.024) but not by strength of other muscle groups or by passive ankle dorsiflexion.

CONCLUSION

Peripheral muscle strength and ankle dorsiflexion are reduced in the long-term in children treated for cancer with chemotherapy. However, neither decreased muscle strength nor reduced ankle dorsiflexion could completely explain reduced scores on the movement-ABC.

Relationships among severity of osteonecrosis, pain, range of motion, and functional mobility in children, adolescents, and young adults with acute lymphoblastic leukemia

BACKGROUND AND PURPOSE

Up to 38% of children receiving treatment for acute lymphoblastic leukemia (ALL) develop osteonecrosis, often without symptoms. Little is known about the association between the degree of osteonecrosis and functional mobility in this population. The purpose of this study was to examine relationships among the degree of osteonecrosis, pain, range of motion (ROM), and functional mobility in people with ALL.

SUBJECTS

Thirty-three subjects aged 5 to 27 years with ALL and osteonecrosis participated.

METHODS

The extent of osteonecrosis was determined by magnetic resonance imaging (MRI) of the hip and knee according to 2 classification systems, including the Association Research Circulation Osseous (ARCO) and a knee staging scale. Pain, hip and knee ROM, and the Timed Up and Down Stairs (TUDS) Test were used as measures.

RESULTS

Correlations were observed between ARCO and hip pain (r=.34), between hip flexion ROM and hip pain (r=-.34), and between knee pain and time on the TUDS Test (r=-.35).

DISCUSSION AND CONCLUSION

Physical therapists should consider that people with ALL may have hip or knee osteonecrosis without clinical symptoms. This notion supports the need for MRI in addition to a comprehensive examination of functional mobility.

Are survivors of acute lymphoblastic leukemia (ALL) at increased risk of cardiovascular disease?

Through a variety of different mechanisms, it appears that survivors of childhood acute lymphoblastic leukemia have an increased prevalence of several cardiovascular risk factors and thus are at increased risk for developing cardiovascular disease. The aim of this paper is to describe the current understanding of particular risk factors, including obesity, physical inactivity, dyslipidemia, insulin resistance, and metabolic syndrome, that may contribute to cardiovascular disease in survivors of childhood ALL. The potential roles of different cancer therapies in the development of these risk factors are discussed. In addition, two other late effects that may affect cardiovascular health are discussed: late-onset anthracycline-induced left ventricular dysfunction and methotrexate-mediated elevations of homocysteine during therapy with the potential for endothelial dysfunction. Lastly, areas needing further investigation to elucidate these risks are highlighted.

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.

A compartmented neuronal culture system in microdevice format

This paper describes a microfabricated compartmented culture system (mu-CCS) for studying the effects of drugs on cultured neurons. We describe the fabrication of the microsystem and show the ability to culture DRG neurons in the microsystem. Furthermore, we demonstrate the ability to culture neurons with extensions growing into adjoining compartments while maintaining fluid isolation between compartments. The axonal growth pattern was controlled along the surface of the glass microelectrode substrate using a micropatterned collagen film. The ability to isolate fluids to selected compartments while simultaneously allowing intercompartmental growth of the axons enables various studies in which selected segments of neurons or populations of neurons can be selectively exposed to biochemical treatment. The neurotoxin vincristine was used as the test vehicle to demonstrate the functionality of the mu-CCS. Vincristine was applied to the axonal compartment to show that the interaction of drugs with DRG neurons progresses in a way similar to neurons cultured/exposed using conventional techniques.

Decrease in motor performance in children with cancer is independent of the cumulative dose of vincristine

BACKGROUND

Impaired performance on motor tasks in children treated for acute lymphoblastic leukemia (ALL) after completion of treatment is often attributed to vincristine (VCR). Whether motor problems persist in other children who receive different cumulative doses of VCR is to the authors' knowledge not known. The objective of the current study was to determine the extent of motor problems in children with ALL, Wilms tumor (WT), B-cell non-Hodgkin lymphoma (B-NHL), and malignant mesenchymal tumors (MMT) and whether these motor problems were related to VCR dose.

METHODS

In 128 children ages 4-12 years who completed treatment after at least 1 year, motor performance was measured using the Movement Assessment Battery for Children (m-ABC).

RESULTS

The m-ABC scores of the total study group were significantly lower than those of the normal population (P < 0.001). There were no differences in scores noted between children with ALL, WT, B-NHL, or MMT. There also were no differences noted between those children with ALL who had received pulses of VCR and steroids during maintenance therapy and those who had not. All groups demonstrated large variability in scores. Scores were not found to be significantly different between those children who had received low (< 20 mg/m(2)), intermediate (20-40 mg/m(2)), or high (> 40 mg/m(2)) cumulative doses of VCR. Cumulative doses of corticosteroids and methotrexate did not affect scores, nor did age at diagnosis and time since the completion of therapy.

CONCLUSIONS

Although motor performance was impaired in all patient groups, no correlation was found between motor performance and the cumulative dose of VCR or other drugs, age, and follow-up time. Future studies have to address several issues, including whether polymorphisms in drug metabolizing genes or drug target genes explain the significant variability noted in the long-term motor outcome of children with cancer.

Lack of neurotoxicity of the vascular targeting agent ZD6126 following repeated i.v. dosing in the rat

The vascular targeting agent ZD6126 is a water-soluble prodrug of N-acetylcolchinol that acts by disrupting the cytoskeleton of tumor endothelial cells. It is currently undergoing clinical evaluation in man. As peripheral neuropathy is a major dose-limiting toxicity associated with tubulin binding agents, the neurotoxic potential of ZD6126 was investigated in male and female Wistar rats. ZD6126 was administered i.v. at up to maximum tolerated doses using subacute (0 to 20 mg/kg/d for 5 days) and chronic (0 to 10 mg/kg/d for 5 days, repeated monthly for 6 months) dosing regimens. A separate study examined a combination of ZD6126 (three cycles of ZD6126 given as in the chronic dosing regimen) and paclitaxel (12 mg/kg/wk for 9 weeks) to assess whether coadministration of ZD6126 altered the time course or magnitude of a paclitaxel-induced neuropathy. Neurotoxic potential was examined using a comprehensive series of tests including a functional observation battery, measurements of muscle strength (forelimb and hind limb grip strength), nociception (tail flick test), locomotor activity, neuropathology, and whole nerve electrophysiology. There was no evidence that ZD6126 induced neurotoxicity in the rat following either subacute or chronic i.v. dosing. In a chronic electrophysiology study, ZD6126 produced a slight slowing of the maturational increase of caudal nerve amplitude, with some evidence of reversibility. However, this was not associated with any changes in caudal nerve conduction velocity, motor nerve conduction velocity or amplitude, functional observation battery behavioral and function parameters (including no effects on tail flick latency), and neuropathology. As expected, paclitaxel administration was associated with a significant decrease in caudal nerve conduction velocity (P = 0.0001). Coadministration of ZD6126 did not increase the neurotoxicity of paclitaxel. These studies suggest that ZD6126 should not induce the peripheral neuropathy associated with other antitubulin chemotherapeutic agents and that ZD6126 may not exacerbate the neurotoxicity of other agents with dose-limiting neuropathies.

Effects of physical therapy intervention for children with acute lymphoblastic leukemia

BACKGROUND

The purpose of this study was to examine the effects of physical therapy intervention in children with acute lymphoblastic leukemia (ALL).

PROCEDURE

Twenty-eight children aged 4-15 years were randomly assigned to an intervention or control group. The intervention group received five sessions of physical therapy and was instructed to perform an individualized home exercise program consisting of ankle dorsiflexion stretching, lower extremity strengthening, and aerobic exercise.

RESULTS

After 4 months children who received physical therapy intervention had significantly improved ankle dorsiflexion active range of motion and knee extension strength (P < 0.01). Differences were not found between the two groups for any of the other dependent variables.

CONCLUSIONS

Physical therapy intervention for children with ALL receiving maintenance chemotherapy improved two body functions important for normal gait. Physical therapy programs initiated earlier in treatment and with greater emphasis on endurance activities may also improve stamina and quality of life (QOL).

Maintenance of ankle range of motion in children treated for acute lymphoblastic leukemia

PURPOSE

This study documented ankle dorsiflexion range of motion (DF-ROM) in children during treatment for leukemia and studied the effects of preventative education and individualized intervention as a standard of care.

METHODS

Active and passive DF-ROM were measured throughout a two-year treatment period and one year after treatment in 40 subjects. Children without health problems and historical controls who had not received therapeutic input were used for comparison.

RESULTS

Active DF-ROM showed an average tendency to decline significantly during treatment, whereas passive DF-ROM did not. Both increased significantly following the end of treatment. There were substantial individual differences around these patterns of average change. Gender (female) was a predictor of negative change in DF-ROM during treatment. Average DF-ROM one year after treatment was significantly greater than for the historical controls and not significantly different from the healthy controls. None of the children required surgical intervention, in contrast to the historical controls.

CONCLUSIONS

Education and intervention appears to have improved DF-ROM outcome in children treated for leukemia.

Motor nervous system impairment persists in long-term survivors of childhood acute lymphoblastic leukemia

BACKGROUND

The objective of the current study was to determine whether therapy for childhood acute lymphoblastic leukemia (ALL) results in long-lasting neurologic signs or electrophysiologic injuries within the motor tracts.

METHODS

Twenty-seven children who were treated for ALL were studied clinically 5 years after the cessation of therapy by means of motor-evoked potentials (MEPs) elicited by magnetic stimulation transcranially and peripherally. An equal number of healthy children matched with regard to age, gender, and height served as the control group.

RESULTS

The MEP latencies to the hands and legs elicited by stimulation at the cortex were prolonged significantly in the children treated for ALL compared with the control group, with the differences being 2.2 milliseconds [ms] (P < 0.001) from the cortex to the thenar on the right side and 2.0 ms (P < 0.001) on the left, and 1.4 ms (P = 0.004) from the cortex to the leg on the right side and 1.3 ms (P = 0.004) on the left. Correspondingly, the MEP latency from the fifth lumbar vertebrae (LV) level to the leg also was prolonged, by 1.0 ms (P = 0.005) on the right side and 0.8 ms (P = 0.005) on the left side. The calculated latency between the cortex and the LV level was not found to be significantly longer in those patients treated for ALL compared with the healthy controls. Neurologic signs, in the form of depressed deep tendon reflexes, were observed in 8% of the patients, whereas approximately 33% of the patients were found to have fine or gross motor difficulties and dysdiadochokinesia.

CONCLUSIONS

Neurologic signs still persisted 5 years after therapy for ALL. Approximately 33% of the patients had fine or gross motor difficulties and dysdiadochokinesia, and demyelinative injuries to the peripheral nerve tracts were found proximally but not within the central nervous system.

Motor nervous pathway function is impaired after treatment of childhood acute lymphoblastic leukemia: a study with motor evoked potentials

BACKGROUND

The objective was to evaluate whether motor nervous pathways are affected when patients are treated for childhood acute lymphoblastic leukemia (ALL).

PROCEDURE

Thirty-two children with ALL were studied at the end of treatment by means of motor evoked potentials (MEPs) elicited by magnetic stimulation (MS) transcranially and peripherally and underwent a detailed neurological examination. Thirty-two healthy children matched with them for age, sex, and height served as a control group.

RESULTS

The latencies of the MEPs were significantly prolonged along the entire motor nervous pathway in the patients with ALL compared with the healthy controls, indicating demyelination in the thick motor fibres. The MEP amplitudes of the distal extremities elicited by stimulation at the brachial plexus and LV spinal level were significantly lowered in the patients treated for ALL, also indicating anatomical or functional loss of descending motor fibres and/or muscle fibres. The MEP amplitudes elicited by cortical MS showed wider variation and no clear abnormalities were found. Neurological signs and symptoms were common after treatment: 41% of the patients had depressed deep tendon reflexes, 31% had fine motor difficulties and 63% gross motor difficulties, and 34% had dysdiadochokinesia. The conduction delay within the peripheral nerve was related to the post-therapeutic interval after administration of vincristine and the lesions within the CNS to the number of injections of intrathecal methotrexate.

CONCLUSIONS

The present results show adverse effects of the ALL treatment on the entire motor nervous pathways. In our experience, the measurement of MEPs by MS provides an objective, painless, and practical tool for assessing the treatment-related neurotoxicity in both the CNS and the peripheral nerves. These disturbances in the motor nervous pathways at the end of treatment raise the question of the long-term effects of ALL treatment on the motor nerve tracts, and have led us to employ MEPs to study these effects in long-term survivors of ALL.

Motor performance of children during treatment for acute lymphoblastic leukemia

BACKGROUND

Daily life motor skills of children with acute lymphoblastic leukemia (ALL) were studied during treatment using the Movement Assessment Battery for Children (Movement ABC). In addition, the possible relation with vincristine treatment was investigated.

PROCEDURE

Seventeen children treated for ALL, aged 4-12 years, were compared to an age- and sex-matched control group.

RESULTS

The leukemia group performed more poorly than the control group on both fine and gross motor skills. In looking at the number of children with ALL who scored in the clinical range of the different subtests, problems in balance skills were found to be most pronounced at the end of induction therapy. Remarkably, half a year after reinduction therapy, problems with balance had decreased, whereas the number of children with fine motor problems had increased.

CONCLUSIONS

A relation between the gross motor problems and vincristine neurotoxicity seems plausible based on a descriptive analysis of the data, but this was not supported statistically.

Limitation of ankle range of motion in survivors of acute lymphoblastic leukemia: a cross-sectional study

BACKGROUND

The purpose of this study was to evaluate and determine the factors related to active and passive dorsiflexion range of motion (DF-ROM) in survivors of acute lymphoblastic leukemia (ALL), which is the most obvious impairment of musculoskeletal function in such children.

PROCEDURE

The subjects included 54 survivors of ALL treated on Dana-Farber Cancer Institute protocols and 54 comparable healthy children. Bilateral active and passive DF-ROM were measured with the knee extended.

RESULTS

The survivors of ALL had significantly less active and passive DF-ROM (6.4 vs. 16.8, 10.5 vs. 18.8 degrees, respectively, P < 0.001) than the comparison children. Weight for age at the time of assessment and change in height during treatment showed significant negative correlations with DF-ROM. Length of time-off treatment was not associated with DF-ROM.

CONCLUSIONS

Multiple regression analyses identified the variables of age at diagnosis and gender as significant predictors of both DF-ROM measures following treatment. Children diagnosed at a younger age and females were at greater risk for restricted DF-ROM. Close monitoring and preventative therapy programs for this complication are warranted for children, especially young girls receiving treatment for ALL.

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.

Chemotherapy for acute lymphoblastic leukemia may cause subtle changes of the spinal cord detectable by somatosensory evoked potentials

Intrathecal chemotherapy has been determined to cause transient or permanent paraparesis due to myelopathy in patients with leukemia or other malignancies. To systematically evaluate the effect of methotrexate on spinal cord function, somatosensory evoked potentials (SEP) were measured in children with acute lymphoblastic leukemia (ALL). A prospective evaluation was performed in 38 consecutive children aged 1.4-15.3 years with newly diagnosed ALL during treatment. Intrathecal methotrexate therapy was included in the therapy schedule of all patients as central nervous system (CNS) therapy in addition to intravenous chemotherapy in 19 standard risk patients and intravenous chemotherapy with cranial irradiation in 19 intermediate or high-risk patients. The measured conduction times were compared with those of 38 control children matched for age, height, and sex. A significant increase in the conduction time of the tibial nerve SEP was found between the Th12 level and the cortex in children with ALL after receiving intrathecal methotrexate therapy during the induction and CNS therapy phases when compared with their controls. The difference of the mean latencies was 1.45 ms (95% CI 0.39-2.51; P < 0.01). There was no significant delay in the median nerve SEP from the brain stem to the cortex, indicating that the conduction delay was in the area of the spinal cord exposed to intrathecal methotrexate. Moreover, the cortical amplitudes of the median nerve SEPs were significantly reduced when measured immediately after intravenous and intrathecal methotrexate and compared to the amplitudes measured after induction therapy in standard risk patients (P = 0.001). Intrathecal methotrexate with systemic chemotherapy causes a deterioration in the somatosensory pathways within the CNS, suggesting also spinal cord dysfunction in children with ALL in addition to the cerebral dysfunction described earlier.