- Neurology - Child Neurology
- Pediatric Neuro-oncology
Program Director, Child Neurology Residency (2014 - Present)
Residency: UCSF Pediatric Department (2006) CA
Internship: UCSF Pediatric Department (2005) CA
Fellowship: Stanford University Child Neurology Residency (2011) CA
Residency: Children's Hospital of Philadelphia Child Neurology (2009) PA
Medical Education: University of California at San Francisco School of Medicine (2004) CA
Board Certification: United Council for Neurologic Subspecialties, Neuro-Oncology (2013)
Board Certification: American Board of Psychiatry and Neurology, Neurology - Child Neurology (2009)
A Clinical and Molecular Risk-Directed Therapy for Newly Diagnosed Medulloblastoma
Historically, medulloblastoma treatment has been determined by the amount of leftover disease present after surgery, also known as clinical risk (standard vs. high risk). Recent studies have shown that medulloblastoma is made up of distinct molecular subgroups which respond differently to treatment. This suggests that clinical risk alone is not adequate to identify actual risk of recurrence. In order to address this, we will stratify medulloblastoma treatment in this phase II clinical trial based on both clinical risk (low, standard, intermediate, or high risk) and molecular subtype (WNT, SHH, or Non-WNT Non-SHH). This stratified clinical and molecular treatment approach will be used to evaluate the following: - To find out if participants with low-risk WNT tumors can be treated with a lower dose of radiation to the brain and spine, and a lower dose of the chemotherapy drug cyclophosphamide while still achieving the same survival rate as past St. Jude studies with fewer side effects. - To find out if adding targeted chemotherapy after standard chemotherapy will benefit participants with SHH positive tumors. - To find out if adding new chemotherapy agents to the standard chemotherapy will improve the outcome for intermediate and high risk Non-WNT Non-SHH tumors. - To define the cure rate for standard risk Non-WNT Non-SHH tumors treated with reduced dose cyclophosphamide and compare this to participants from the past St. Jude study. All participants on this study will have surgery to remove as much of the primary tumor as safely possible, radiation therapy, and chemotherapy. The amount of radiation therapy and type of chemotherapy received will be determined by the participant's treatment stratum. Treatment stratum assignment will be based on the tumor's molecular subgroup assignment and clinical risk. The participant will be assigned to one of three medulloblastoma subgroups determined by analysis of the tumor tissue for tumor biomarkers: - WNT (Strata W): positive for WNT biomarkers - SHH (Strata S): positive for SHH biomarkers - Non-WNT Non-SHH, Failed, or Indeterminate (Strata N): negative for WNT and SHH biomarkers or results are indeterminable Participants will then be assigned to a clinical risk group (low, standard, intermediate, or high) based on assessment of: - How much tumor is left after surgery - If the cancer has spread to other sites outside the brain [i.e., to the spinal cord or within the fluid surrounding the spinal cord, called cerebrospinal fluid (CSF)] - The appearance of the tumor cells under the microscope - Whether or not there are chromosomal abnormalities in the tumor, and if present, what type (also called cytogenetics analysis)
Stanford is currently not accepting patients for this trial. For more information, please contact Peds Hem/Onc CRAs, 650-723-5535.
MEK Inhibitor Mirdametinib (PD-0325901) in Patients With Neurofibromatosis Type 1 Associated Plexiform Neurofibromas
This study evaluates mirdametinib (PD-0325901) in the treatment of symptomatic inoperable neurofibromatosis type-1 (NF1)-associated plexiform neurofibromas (PNs). All participants will receive mirdametinib (PD-0325901). Eligible participants may continue in a long-term follow-up phase.
Stanford is currently not accepting patients for this trial.
Methylphenidate HCl or Modafinil in Treating Young Patients With Excessive Daytime Sleepiness After Cancer Therapy
RATIONALE: Methylphenidate hydrochloride or modafinil may help reduce daytime sleepiness and improve the quality of life of patients with excessive daytime sleepiness after cancer therapy. It is not yet known whether methylphenidate hydrochloride or modafinil are more effective than a placebo in reducing daytime sleepiness in these patients. PURPOSE: This randomized phase II trial is studying methylphenidate hydrochloride or modafinil to see how well they work compared with a placebo in treating young patients with excessive daytime sleepiness after cancer therapy.
Stanford is currently not accepting patients for this trial. For more information, please contact Jennifer Lew, (650) 725 - 4318.
Palbociclib Isethionate in Treating Younger Patients With Recurrent, Progressive, or Refractory Central Nervous System Tumors
This phase I trial studies the side effects and best dose of palbociclib isethionate in treating younger patients with central nervous system tumors that have grown, come back, or not responded to treatment. Palbociclib isethionate may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth.
Stanford is currently not accepting patients for this trial. For more information, please contact Prianka Kumar, 650-724-3866.
Pediatric Functional Neurological Disorder: Demographic and Clinical Factors Impacting Care
JOURNAL OF CHILD NEUROLOGY
This is a multicenter retrospective EMR-based chart review of 88 patients aged 3-21 years admitted for evaluation of functional neurologic disorder (FND). We sought to establish characteristics associated with FND, calculate incidence of abnormal neurodiagnostic findings, and determine features associated with variability in workup and treatment. FND patients were 65% female, 40% White, 33% Hispanic, and 88% primarily English speaking with median 13.9 years. We detected variability in management by age, ethnicity, psychiatric comorbidity, and hospital site. Our findings suggest limited utility to CTs in this setting (100% normal) and that workup can be safely informed by physical exam, which predicted abnormal MRI and LP results. We favor screening for adverse childhood experiences in FND patients. Hospitalization may be a rare opportunity for psychiatry contact.
View details for DOI 10.1177/08830738221113899
View details for Web of Science ID 000825063200001
View details for PubMedID 35815864
MAJOR TUMOR REGRESSIONS IN H3K27M-MUTATED DIFFUSE MIDLINE GLIOMA (DMG) FOLLOWING SEQUENTIAL INTRAVENOUS (IV) AND INTRACEREBROVENTRICULAR (ICV) DELIVERY OF GD2-CAR T-CELLS
OXFORD UNIV PRESS INC. 2022: 20-21
View details for Web of Science ID 000840122400074
GD2-CAR T cell therapy for H3K27M-mutated diffuse midline gliomas.
Diffuse intrinsic pontine glioma (DIPG) and other H3K27M-mutated diffuse midline gliomas (DMG) are universally lethal paediatric central nervous system tumours1. We previously discovered that the disialoganglioside GD2 is highly expressed on H3K27M-mutant glioma cells and demonstrated promising preclinical efficacy of GD2-directed chimeric antigen receptor (CAR) T cells2, providing the rationale for a first-in-human Phase 1 clinical trial (NCT04196413). Because CAR T-cell-induced brainstem inflammation can result in obstructive hydrocephalus, increased intracranial pressure, and dangerous tissue shifts, neurocritical care precautions were incorporated. Here we present the clinical experience from the first four patients with H3K27M-mutant DIPG/DMG treated with GD2-CAR T cells (GD2-CART) at dose level 1 (1e6 GD2-CAR T cells/kg administered intravenously). Patients who exhibited clinical benefit were eligible for subsequent GD2-CAR T infusions administered intracerebroventricularly3. Toxicity was largely related to tumor location and reversible with intensive supportive care. On-target, off-tumor toxicity was not observed. Three of four patients exhibited clinical and radiographic improvement. Proinflammatory cytokines were increased in plasma and cerebrospinal fluid (CSF). Transcriptomic analyses of 65,598 single cells from CAR T cell products and CSF elucidate heterogeneity in response between subjects and administration routes. These early results underscore the promise of this approach for H3K27M+ DIPG/DMG therapy.
View details for DOI 10.1038/s41586-022-04489-4
View details for PubMedID 35130560
Risk Factors for Treatment Refractory and Relapsed Optic Pathway Glioma in Children with Neurofibromatosis Type 1.
BACKGROUND: Nearly one-third of patients with neurofibromatosis type 1-associated optic pathway glioma (NF1-OPG) fail frontline chemotherapy; however, little is known about risk factors for treatment failure.METHODS: We performed a retrospective multi-institutional cohort study to identify baseline risk factors for treatment-refractory/relapsed disease and poor visual outcome in children with NF1-OPG. Refractory/relapsed NF1-OPG was defined as requirement of two or more treatment regimens due to progression or relapse.RESULTS: Of 111 subjects eligible for inclusion, adequate clinical and visual data were available for 103 subjects from 7 institutions. Median follow-up from initiation of first chemotherapy regimen was 95 months (range 13-185). Eighty-four (82%) subjects received carboplatin-based frontline chemotherapy. Forty-five subjects (44%) experienced refractory/relapsed disease, with median time of 21.5 months (range 2-149) from initiation of first treatment to start of second treatment. The proportion of patients without refractory/relapsed disease at 2 and 5 years was 78% and 60%. In multivariable analyses, age less than 24 months at initial treatment, posterior tumor location, and familial inheritance were associated with refractory/relapsed NF1-OPG by 2 years. Both age less than 24 months and posterior tumor location were associated with refractory/relapsed NF1-OPG by 5 years. Subjects with moderate to severe vision loss at last follow-up were more likely to have posterior tumor location, optic disc abnormalities, or abnormal visual acuity at initial treatment.CONCLUSION: Young age, posterior tumor location, and optic disc abnormalities may identify patients with the greatest likelihood of refractory/relapsed NF1-OPG and poor visual outcomes, and who may benefit from newer treatment strategies.
View details for DOI 10.1093/neuonc/noac013
View details for PubMedID 35018469
Machine-learning Approach to Differentiation of Benign and Malignant Peripheral Nerve Sheath Tumors: A Multicenter Study
AMER ASSOC NEUROLOGICAL SURGEONS. 2021
View details for Web of Science ID 000680654900137
GD2 CAR T cells mediate clinical activity and manageable toxicity in children and young adults with DIPG and H3K27M-mutated diffuse midline gliomas.
AMER ASSOC CANCER RESEARCH. 2021
View details for Web of Science ID 000680263501014
Machine-Learning Approach to Differentiation of Benign and Malignant Peripheral Nerve Sheath Tumors: A Multicenter Study.
BACKGROUND: Clinicoradiologic differentiation between benign and malignant peripheral nerve sheath tumors (PNSTs) has important management implications.OBJECTIVE: To develop and evaluate machine-learning approaches to differentiate benign from malignant PNSTs.METHODS: We identified PNSTs treated at 3 institutions and extracted high-dimensional radiomics features from gadolinium-enhanced, T1-weighted magnetic resonance imaging (MRI) sequences. Training and test sets were selected randomly in a 70:30 ratio. A total of 900 image features were automatically extracted using the PyRadiomics package from Quantitative Imaging Feature Pipeline. Clinical data including age, sex, neurogenetic syndrome presence, spontaneous pain, and motor deficit were also incorporated. Features were selected using sparse regression analysis and retained features were further refined by gradient boost modeling to optimize the area under the curve (AUC) for diagnosis. We evaluated the performance of radiomics-based classifiers with and without clinical features and compared performance against human readers.RESULTS: A total of 95 malignant and 171 benign PNSTs were included. The final classifier model included 21 imaging and clinical features. Sensitivity, specificity, and AUC of 0.676, 0.882, and 0.845, respectively, were achieved on the test set. Using imaging and clinical features, human experts collectively achieved sensitivity, specificity, and AUC of 0.786, 0.431, and 0.624, respectively. The AUC of the classifier was statistically better than expert humans (P=.002). Expert humans were not statistically better than the no-information rate, whereas the classifier was (P=.001).CONCLUSION: Radiomics-based machine learning using routine MRI sequences and clinical features can aid in evaluation of PNSTs. Further improvement may be achieved by incorporating additional imaging sequences and clinical variables into future models.
View details for DOI 10.1093/neuros/nyab212
View details for PubMedID 34131749
- SINGLE CELL RNA SEQUENCING FROM THE CSF OF SUBJECTS WITH H3K27M+DIPG/DMG TREATED WITH GD2 CAR T-CELLULAR THERAPY OXFORD UNIV PRESS INC. 2021: 39
- GD2 CAR T-CELLS MEDIATE CLINICAL ACTIVITY AND MANAGEABLE TOXICITY IN CHILDREN AND YOUNG ADULTS WITH H3K27M-MUTATED DIPG AND SPINAL CORD DMG OXFORD UNIV PRESS INC. 2021: 49-50
Effects of Age on White Matter Microstructure in Children With Neurofibromatosis Type 1.
Journal of child neurology
Children with neurofibromatosis type 1 (NF1) often report cognitive challenges, though the etiology of such remains an area of active investigation. With the advent of treatments that may affect white matter microstructure, understanding the effects of age on white matter aberrancies in NF1 becomes crucial in determining the timing of such therapeutic interventions. A cross-sectional study was performed with diffusion tensor imaging from 18 NF1 children and 26 age-matched controls. Fractional anisotropy was determined by region of interest analyses for both groups over the corpus callosum, cingulate, and bilateral frontal and temporal white matter regions. Two-way analyses of variance were done with both ages combined and age-stratified into early childhood, middle childhood, and adolescence. Significant differences in fractional anisotropy between NF1 and controls were seen in the corpus callosum and frontal white matter regions when ages were combined. When stratified by age, we found that this difference was largely driven by the early childhood (1-5.9 years) and middle childhood (6-11.9 years) age groups, whereas no significant differences were appreciable in the adolescence age group (12-18 years). This study demonstrates age-related effects on white matter microstructure disorganization in NF1, suggesting that the appropriate timing of therapeutic intervention may be in early childhood.
View details for DOI 10.1177/08830738211008736
View details for PubMedID 34048307
EXAMINING DIFFUSION, ARTERIAL SPIN-LABELED PERFUSION, AND VOLUMETRIC CHANGES IN THE NEUROFIBROMATOSIS TYPE 1 BRAIN USING AN ATLAS-BASED, MULTI-PARAMETRIC APPROACH
OXFORD UNIV PRESS INC. 2020: 418
View details for Web of Science ID 000606080100609
WHITE MATTER DIFFERENCES IN CHILDREN WITH NF1 COMPARED TO CONTROLS
OXFORD UNIV PRESS INC. 2020: 419–20
View details for Web of Science ID 000606080100615
ENROLLMENT AND CLINICAL CHARACTERISTICS OF NEWLY DIAGNOSED, NEUROFIBROMATOSIS TYPE 1 ASSOCIATED OPTIC PATHWAY GLIOMA (NF1-OPG): PRELIMINARY RESULTS FROM AN INTERNATIONAL MULTI-CENTER NATURAL HISTORY STUDY
OXFORD UNIV PRESS INC. 2020: 419
View details for Web of Science ID 000606080100614
Clinical Features of Neurofibromatosis Type 2 (NF2) in Children during the First Decade of Life
WILEY. 2019: S114
View details for Web of Science ID 000488891800172
Neurofibromatosis 2 in children presenting during the first decade of life.
To educate providers to recognize the clinical presentation of neurofibromatosis 2 (NF2) in young children.A retrospective analysis of 22 children with NF2 from 4 tertiary care NF referral centers was performed. Age and signs/symptoms at initial presentation, age at NF2 diagnosis, family history, clinical/radiographic NF2 features, NF2 genetic testing results, and treatments were assessed.The average age at initial clinical presentation was 48.1 months, while the average age at NF2 diagnosis was 77.2 months. Children with a family history of NF2 (23%) tended to present earlier (mean 39.2 vs 50.7 months) and have shorter times to NF2 diagnosis (mean 1.6 vs 37.2 months). Vision/eye complaints (n = 9; 41%) were the most commonly reported presenting signs/symptoms. Meningiomas (n = 7; 32%) and ocular abnormalities (n = 5; 23%) were the most frequently identified initial NF2 features. Vestibular (n = 17; 77%) and peripheral (n = 15; 68%) schwannomas were the most common abnormalities encountered over the study period. Seventeen (77%) children required treatment, most frequently for vestibular schwannomas (n = 9; 41%), peripheral schwannomas (n = 7; 32%), and meningiomas (n = 7; 32%). Genetic testing was available for 13 individuals, in whom nonsense mutations were most commonly identified (n = 7; 54%).Although uncommon, a substantial number of individuals with NF2 come to medical attention in early childhood. The finding of meningioma or characteristic ocular abnormalities (retinal hamartomas and epiretinal membranes) in young children should raise clinical suspicion for NF2 and prompt immediate referral to appropriate specialists for diagnosis and management.
View details for DOI 10.1212/WNL.0000000000008065
View details for PubMedID 31363058
Comment: Genotype-phenotype correlations in NF1: A case for routine genetic testing
2018; 90 (8): 380
View details for PubMedID 29367437
Pediatric Bickerstaff brainstem encephalitis: a systematic review of literature and case series
JOURNAL OF NEUROLOGY
2018; 265 (1): 141–50
To characterize the phenotype of pediatric Bickerstaff's brainstem encephalitis (BBE) and evaluate prognostic features in the clinical course, diagnostic studies, and treatment exposures.We systematically reviewed PubMed, Web of Science, and SCOPUS databases as well as medical records at the Lucile Packard Children's Hospital to identify cases of pediatric BBE. Inclusion required all of the following criteria: age ≤ 20 years, presence of somnolence or alterations in mental status at the time of presentation or developed within 7 days of presentation, ataxia, and ophthalmoplegia.We reviewed 682 manuscripts, identifying a total of 47 pediatric BBE cases. We also describe five previously unreported cases. The phenotype of these pediatric patients was similar to previously published literature. Sixty-eight percent of patients demonstrated positive anti-GQ1b antibody titers, yet the presence of these antibodies was not associated with longer times to recovery. Patients with neuroimaging abnormalities featured a longer median time to recovery, but this was not statistically significant (p = 0.124). Overall, patients treated with any form of immunotherapy (intravenous immunoglobulin, steroids, or plasmapheresis) demonstrated shorter median time to resolution of symptoms compared to supportive therapy, although this trend was not statistically significant (p = 0.277). Post-hoc t tests revealed a trend towards use of immunotherapy against supportive care alone (p = 0.174).Our study identified clinical, radiologic, and treatment features that may hold prognostic value for children with BBE. The role of immunotherapy remains under investigation but may prove of utility with further, randomized controlled studies in this rare disease.
View details for PubMedID 29177548
Surgical outcomes of pediatric spinal cord astrocytomas: systematic review and meta-analysis.
Journal of neurosurgery. Pediatrics
OBJECTIVE Pediatric spinal astrocytomas are rare spinal lesions that pose unique management challenges. Therapeutic options include gross-total resection (GTR), subtotal resection (STR), and adjuvant chemotherapy or radiation therapy. With no randomized controlled trials, the optimal management approach for children with spinal astrocytomas remains unclear. The aim of this study was to conduct a systematic review and meta-analysis on pediatric spinal astrocytomas. METHODS The authors performed a systematic review of the PubMed/MEDLINE electronic database to investigate the impact of histological grade and extent of resection on overall survival among patients with spinal cord astrocytomas. They retained publications in which the majority of reported cases included astrocytoma histology. RESULTS Twenty-nine previously published studies met the eligibility criteria, totaling 578 patients with spinal cord astrocytomas. The spinal level of intramedullary spinal cord tumors was predominantly cervical (53.8%), followed by thoracic (40.8%). Overall, resection was more common than biopsy, and GTR was slightly more commonly achieved than STR (39.7% vs 37.0%). The reported rates of GTR and STR rose markedly from 1984 to 2015. Patients with high-grade astrocytomas had markedly worse 5-year overall survival than patients with low-grade tumors. Patients receiving GTR may have better 5-year overall survival than those receiving STR. CONCLUSIONS The authors describe trends in the management of pediatric spinal cord astrocytomas and suggest a benefit of GTR over STR for 5-year overall survival.
View details for PubMedID 30028275
Optic Pathway Gliomas in Neurofibromatosis Type 1
JOURNAL OF CHILD NEUROLOGY
2018; 33 (1): 73–81
Neurofibromatosis type 1 (NF1) is one of the most common brain tumor predisposition syndromes, in which affected children are prone to the development of low-grade gliomas. While NF1-associated gliomas can be found in several brain regions, the majority arise in the optic nerves, chiasm, tracts, and radiations (optic pathway gliomas; OPGs). Owing to their location, 35-50% of affected children present with reduced visual acuity. Unfortunately, despite tumor stabilization following chemotherapy, vision does not improve in most children. For this reasons, more effective therapies are being sought that reflect a deeper understanding of the NF1 gene and the use of authenticated Nf1 genetically-engineered mouse strains. The implementation of these models for drug discovery and validation has galvanized molecularly-targeted clinical trials in children with NF1-OPG. Future research focused on defining the cellular and molecular factors that underlie optic glioma development and progression also has the potential to provide personalized risk assessment strategies for this pediatric population.
View details for PubMedID 29246098
View details for PubMedCentralID PMC5739070
Brain Perfusion and Diffusion Abnormalities in Children Treated for Posterior Fossa Brain Tumors.
journal of pediatrics
To compare cerebral perfusion and diffusion in survivors of childhood posterior fossa brain tumor with neurologically normal controls and correlate differences with cognitive dysfunction.We analyzed retrospectively arterial spin-labeled cerebral blood flow (CBF) and apparent diffusion coefficient (ADC) in 21 patients with medulloblastoma (MB), 18 patients with pilocytic astrocytoma (PA), and 64 neurologically normal children. We generated ANCOVA models to evaluate treatment effects on the cerebral cortex, thalamus, caudate, putamen, globus pallidus, hippocampus, amygdala, nucleus accumbens, and cerebral white matter at time points an average of 5.7 years after original diagnosis. A retrospective review of patient charts identified 12 patients with neurocognitive data and in whom the relationship between IQ and magnetic resonance imaging variables was assessed for each brain structure.Patients with MB (all treated with surgery, chemotherapy, and radiation) had significantly lower global CBF relative to controls (10%-23% lower, varying by anatomic region, all adjusted P < .05), whereas patients with PA (all treated with surgery alone) had normal CBF. ADC was decreased specifically in the hippocampus and amygdala of patients with MB and within the amygdala of patients with PA but otherwise remained normal after therapy. In the patients with tumor previously evaluated for IQ, regional ADC, but not CBF, correlated with IQ (R(2) = 0.33-0.75).The treatment for MB, but not PA, was associated with globally reduced CBF. Treatment in both tumor types was associated with diffusion abnormalities of the mesial temporal lobe structures. Despite significant perfusion abnormalities in patients with MB, diffusion, but not perfusion, correlated with cognitive outcomes.
View details for DOI 10.1016/j.jpeds.2017.01.019
View details for PubMedID 28187964
PSYCHIATRIC SYMPTOMS IN CHILDREN WITH SUPRASELLAR TUMORS
OXFORD UNIV PRESS INC. 2016: 46
View details for Web of Science ID 000379749000178
Reduced Cerebral Arterial Spin-Labeled Perfusion in Children with Neurofibromatosis Type 1
AMERICAN JOURNAL OF NEURORADIOLOGY
2013; 34 (9): 1823-1828
BACKGROUND AND PURPOSE:Neurofibromatosis type 1 is associated with increased risk for stroke, cerebral vasculopathy, and neurocognitive deficits, but underlying hemodynamic changes in asymptomatic children remain poorly understood. We hypothesized that children with neurofibromatosis type 1 have decreased cerebral blood flow.MATERIALS AND METHODS:Arterial spin-labeled CBF was measured in 14 children with neurofibromatosis type 1 (median age, 9.7 years; mean, 10.2 years; range, 22 months to 18 years) and compared with age-matched control subjects on 3T MR imaging. Three-dimensional pseudocontinuous spin-echo arterial spin-labeled technique was used. Measurements were obtained at cortical gray matter of bilateral cerebral hemispheres and centrum semiovale by use of the ROI method. Comparison by Mann-Whitney test was used, with Bonferroni-adjusted P values ≤.004 judged as significant.RESULTS:We identified 7 of 12 areas with significantly diminished arterial spin-labeled CBF in patients with neurofibromatosis type 1 compared with control subjects. These areas included the anterior cingulate gyrus (P = .001), medial frontal cortex (P = .004), centrum semiovale (P = .004), temporo-occipital cortex (P = .002), thalamus (P = .001), posterior cingulate gyrus (P = .002), and occipital cortex (P = .001). Among patients with neurofibromatosis type 1, there were no significant differences in these regions on the basis of the presence of neurofibromatosis type 1 spots or neurocognitive deficits.CONCLUSIONS:Reduced cerebral perfusion was seen in children with neurofibromatosis type 1, particularly in the posterior circulation and the vascular borderzones of the middle and posterior cerebral arteries.
View details for DOI 10.3174/ajnr.A3649
View details for Web of Science ID 000329848800034
View details for PubMedID 23764727
- Anti-N-methyl-D-aspartate receptor encephalitis: what's in a name? journal of pediatrics 2013; 162 (4): 673-675
Concurrent cyclophosphamide and craniospinal radiotherapy for pediatric high-risk embryonal brain tumors
JOURNAL OF NEURO-ONCOLOGY
2012; 110 (2): 287-291
Embryonal tumors are an aggressive subtype of high-grade, pediatric central nervous system (CNS) tumors often with dismal survival rates. The 5-year survival for highest-risk embryonal tumors may be as low as 10 %. We report feasibility and efficacy from our experience using intravenous (IV) cyclophosphamide concurrently with craniospinal radiation (CSI) in high-risk embryonal CNS tumors of childhood. Ten consecutive children (aged: 3.5-15.5 years, median: 10.2 years, six male) with high-risk embryonal tumors, including: large cell/anaplastic medulloblastoma (6), atypical teratoid rhabdoid tumor (1), and leptomeningeal primitive neuroectodermal tumor (3), were treated with IV cyclophosphamide 1 g/M(2) on days 1 and 2 of CSI. Following a median of 36 Gy CSI plus tumor boosts, adjuvant treatment consisted of 21 doses of oral etoposide (7) and alkylator based chemotherapy from five to eight cycles in all. Of the ten patients thus treated, six remain alive with no evidence of disease and four are deceased. Median survival was 3.3 years, with a 3-year progression-free survival of 50 % (5/10). Median follow-up was: 3.3 years (range: 5 months-12.9 years) in the five patients with progression, median time-to-progression was: 1.3 years (range: 1 month-3 years). Median follow-up in the patients without progression is 8.8 years (range: 3-12.9 years). Complications due to adjuvant chemotherapy were typical and included myelosupression (10), necessitating shortened duration of chemotherapy in three, and hemorrhagic cystitis (1). In high-risk embryonal CNS tumors, cyclophosphamide given concurrently with CSI is well tolerated. Early results suggest that a phase II trial is warranted.
View details for DOI 10.1007/s11060-012-0969-2
View details for Web of Science ID 000311208100017
View details for PubMedID 22941430
Cranial Irradiation Increases Risk of Stroke in Pediatric Brain Tumor Survivors
2012; 43 (11): 3035-U418
The purposes of this study were to determine the incidence of neurovascular events as late complications in pediatric patients with brain tumor and to evaluate radiation as a risk factor.Patients were ascertained using the tumor database of a pediatric tertiary care center. Included patients had a primary brain tumor, age birth to 21 years, initial treatment January 1, 1993, to December 31, 2002, and at least 2 visits with neuro-oncology. Radiation exposure included: whole brain, whole brain plus a focal boost, or focal brain. The primary outcome was stroke or transient ischemic attack.Of 431 subjects, 14 had 19 events of stroke or transient ischemic attack over a median follow-up of 6.3 years. The incidence rate was 548/100 000 person-years. Overall, 61.5% of subjects received radiation, including 13 of 14 subjects with events. Median time from first radiation to first event was 4.9 years. The stroke/transient ischemic attack hazard ratio for any brain irradiation was 8.0 (95% CI, 1.05-62; P=0.045); for the circle of Willis, radiation was 9.0 (95% CI, 1.2-70; P=0.035); and for focal noncircle of Willis, radiation was 3.4 (95% CI, 0.21-55; P=0.38).The incidence of neurovascular events in this population is 100-fold higher than in the general pediatric population and cranial irradiation is an important risk factor. By defining the incidence of this late effect, physicians are better able to counsel parents regarding treatment, monitor patients at risk, and target a population for primary stroke prevention in future studies.
View details for DOI 10.1161/STROKEAHA.112.661561
View details for Web of Science ID 000310432800296
View details for PubMedID 22968468
View details for PubMedCentralID PMC3492057
Subependymal Giant Cell Astrocytoma (SEGA) Treatment Update
CURRENT TREATMENT OPTIONS IN NEUROLOGY
2011; 13 (4): 380-385
OPINION STATEMENT: Rates of regrowth after resection of subependymal giant cell astrocytoma (SEGA) are low, making surgical resection a successful and permanent therapeutic strategy. In addition to surgical resection of SEGAs, other treatment options now include medications and Gamma Knife™ therapy. Advising patients on medical versus surgical management of SEGAs is currently not easy. SEGAs have been reported to regrow if mTOR inhibitor therapy is stopped, raising the possibility that long-term medication may be required to prevent tumor growth and hydrocephalus. The question of regrowth following medication withdrawal will need to be addressed in more patients to help establish the optimal duration of therapy. The risks of surgery include acute morbidity and the permanent need for ventriculoperitoneal shunting, which must be balanced against the adverse effects of mTOR inhibitors, including immunosuppression (infections, mouth sores), hypercholesterolemia, and the need for chronic drug monitoring. Some additional benefits of mTOR inhibition in patients with tuberous sclerosis complex, however, may include shrinkage of angiofibromas and angiomyolipomas as well as a possible decrease in seizure burden. Recent reports of successful nonsurgical treatment of SEGAs are promising, and it is hoped that further specifics on dosing, duration, and long-term outcome will help patients and physicians to make informed therapeutic choices.Present treatment recommendations for SEGAs include routine surveillance neuroimaging and close clinical follow-up, paying particular attention to signs and symptoms of acute hydrocephalus. If symptoms arise, or if serial neuroimaging demonstrates tumor growth, neurosurgical intervention is recommended. When gross total resection is impossible, rapamycin and everolimus should be considered, but may not offer a durable response.
View details for DOI 10.1007/s11940-011-0123-z
View details for Web of Science ID 000292402500005
View details for PubMedID 21465222
View details for PubMedCentralID PMC3130084
- 50 Years Ago in THE JOURNAL OF PEDIATRICS A Critical Evaluation of Therapy of Febrile Seizures JOURNAL OF PEDIATRICS 2010; 156 (3): 449-449