Bio

Clinical Focus


  • Pediatric Neuro-Oncology
  • Neurology - Child Neurology

Academic Appointments


Administrative Appointments


  • Pediatric Neuro-Oncology Fellowship Director, Stanford (2012 - Present)

Professional Education


  • Board Certification, United Council of Neurologic Subspecialities, Neuro-Oncology (2011)
  • Board Certification: Neurology - Child Neurology, American Board of Psychiatry and Neurology (2007)
  • Board Certification: Pediatrics, American Board of Pediatrics (2007)
  • Residency:Brown University Hospitals (2002) RI
  • Residency:Children's Hospital and Regional Medical Center (2006) WA
  • Fellowship:, Packard Children's & Stanford Hospital, Neuro-Oncology (2007)
  • Medical Education:University of Missouri School of Medicine (2000) MO
  • Masters:, Stanford University, Epidemiology (2009)

Research & Scholarship

Current Research and Scholarly Interests


My research interests involve the epidemiology, treatment and diagnosis of pediatric and young adult brain tumors. I am also interested in long-term neurologic effects and designing clinical trials to treat brain and spinal cord tumors.

Clinical Trials


  • Bevacizumab and Lapatinib in Children With Recurrent or Refractory Ependymoma Not Recruiting

    The goal of this clinical research study is to learn if the combination of Avastin (bevacizumab) and Tykerb (lapatinib) can help to control ependymoma in pediatric patients. The safety of this drug combination will also be studied.

    Stanford is currently not accepting patients for this trial. For more information, please contact Carissa Bailey, (650) 725 - 4708.

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  • Single-agent Erlotinib in Patients Previously Treated With Oral Etoposide in Protocol OSI-774-205 Not Recruiting

    Patients that were assigned to the oral etoposide treatment arm in protocol OSI-774-205 and either progressed while on study or discontinued due to unacceptable toxicity related to etoposide will be allowed to participate in this study to assess the safety profile of single-agent erlotinib in patients with recurrent or refractory pediatric ependymoma.

    Stanford is currently not accepting patients for this trial. For more information, please contact Carissa Bailey, (650) 725 - 4708.

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  • Vismodegib in Treating Younger Patients With Recurrent or Refractory Medulloblastoma Not Recruiting

    This phase II trial studies how well vismodegib works in treating younger patients with recurrent or refractory medulloblastoma. Vismodegib may slow the growth of tumor cells.

    Stanford is currently not accepting patients for this trial. For more information, please contact Christina Huang, 650-723-0574.

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  • An Open-label Safety and Tolerability Study of ISIS SMNRx in Patients With Spinal Muscular Atrophy Who Previously Participated in ISIS 396443-CS1 Not Recruiting

    This study will test the safety and tolerability of ISIS-SMNRx administered into the spinal fluid as a single injection in patients with Spinal Muscular Atrophy, who previously participated in ISIS 396443-CS1

    Stanford is currently not accepting patients for this trial. For more information, please contact Shirley Paulose, 650-724-3792.

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  • DNA Analysis of Tumor Tissue Samples From Patients With Diffuse Brain Stem Glioma Not Recruiting

    This multi-institutional study will prospectively collect tumor and constitutional tissue samples from patients with diffuse brainstem glioma and other types of brainstem gliomas either during therapy or at autopsy to perform an extensive analysis of genetic and molecular abnormalities in these tumors.

    Stanford is currently not accepting patients for this trial. For more information, please contact Carissa Bailey , 650-725-4708.

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  • Modafinil in Treating Children With Memory and Attention Problems Caused by Cancer Treatment for a Brain Tumor Recruiting

    RATIONALE: Modafinil may help improve memory, attention, and fatigue caused by cancer treatment. PURPOSE: This phase II randomized trial studies how well modafinil works in treating children with memory and attention problems caused by cancer treatment for a brain tumor.

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  • Erlotinib Versus Oral Etoposide in Patients With Recurrent or Refractory Pediatric Ependymoma Not Recruiting

    This is a phase 2 study to evaluate the efficacy of single-agent erlotinib versus oral etoposide in patients with recurrent or refractory pediatric ependymoma.

    Stanford is currently not accepting patients for this trial. For more information, please contact Carissa Bailey, (650) 725 - 4708.

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  • Selumetinib in Treating Young Patients With Recurrent or Refractory Low Grade Glioma Recruiting

    This phase I/II trial studies the side effects and the best dose of selumetinib and how well it works in treating young patients with recurrent or refractory low grade glioma. Selumetinib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth.

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Teaching

Graduate and Fellowship Programs


Publications

Journal Articles


  • Birth Anomalies and Obstetric History as Risks for Childhood Tumors of the Central Nervous System PEDIATRICS Partap, S., Maclean, J., Von Behren, J., Reynolds, P., Fisher, P. G. 2011; 128 (3): E652-E657

    Abstract

    The causes of childhood central nervous system (CNS) tumors are largely unknown. Birth characteristics have been examined as possible risk factors for childhood CNS tumors, although the studies have been underpowered and inconclusive. We hypothesized that birth anomalies and a mother's history of previous pregnancy losses, as a proxy for genetic defects, increase the risk for CNS tumors.From the California Cancer Registry, we identified 3733 patients aged 0 to 14 years with CNS tumors, diagnosed from 1988 through 2006 and linked to a California birth certificate. Four controls were matched to each patient. We calculated odds ratios (ORs) for the reported presence of a birth defect and for history of pregnancy losses by using logistic regression, adjusted for race, Hispanic ethnicity, maternal age, birth weight, and birth order.Offspring from mothers who had ? 2 fetal losses after 20 weeks' gestation had a threefold risk for CNS tumors (OR: 3.13 [95% confidence interval (CI): 1.32-7.41]) and a 14-fold risk for high-grade glioma (OR: 14.28 [95% CI: 1.56-130.65]). Birth defects increased risk for the CNS cancers medulloblastoma (OR: 1.70 [95% CI: 1.12-2.57]), primitive neuroectodermal tumor (OR: 3.64 [95% CI: 1.54-8.56]), and germ cell tumors (OR: 6.40 [95% CI: 2.09-19.56]).Multiple pregnancy losses after 20 weeks' gestation and birth defects increase the risk of a childhood CNS tumor. Previous pregnancy losses and birth defects may be surrogate markers for gene defects in developmental pathways that lead to CNS tumorigenesis.

    View details for DOI 10.1542/peds.2010-3637

    View details for Web of Science ID 000295406100022

    View details for PubMedID 21824884

  • Cerebrovascular disease in childhood cancer survivors A Children's Oncology Group Report NEUROLOGY Morris, B., Partap, S., Yeom, K., Gibbs, I. C., Fisher, P. G., King, A. A. 2009; 73 (22): 1906-1913

    Abstract

    Curative therapy for childhood cancer has dramatically improved over past decades. Therapeutic radiation has been instrumental in this success. Unfortunately, irradiation is associated with untoward effects, including stroke and other cerebrovascular disease (CVD). The Children's Oncology Group (COG) has developed guidelines for screening survivors at risk for persistent or late sequelae of cancer therapy.This review summarizes the pathophysiology and relevant manifestations of radiation-induced CVD and outlines the specific patient groups at risk for early-onset stroke. The reader will be alerted to the availability of the COG recommendations for monitoring, and, when applicable, specific screening and treatment recommendations will be highlighted.A multidisciplinary task force critically reviewed the existing literature and scored the evidence to establish the current COG guidelines for monitoring health of survivors treated with head and neck irradiation.Previous head and neck exposure to therapeutic radiation is associated with latent CVD and increased risk for stroke in some patient groups. Common manifestations of radiation-induced CVD includes steno-occlusive disease, moyamoya, aneurysm, mineralizing microangiopathy, vascular malformations, and strokelike migraines.Risk for stroke is increased in survivors of pediatric CNS tumors, Hodgkin lymphoma, and acute lymphoblastic leukemia who received radiation to the brain and/or neck. As the population of survivors ages, vigilance for stroke and cerebrovascular disease needs to continue based on specific exposures during curative cancer therapy.

    View details for DOI 10.1212/WNL.0b013e3181c17ea8

    View details for Web of Science ID 000272205200015

    View details for PubMedID 19812380

  • Surveillance imaging in children with malignant CNS tumors: low yield of spine MRI. Journal of neuro-oncology Perreault, S., Lober, R. M., Carret, A., Zhang, G., Hershon, L., Décarie, J., Vogel, H., Yeom, K. W., Fisher, P. G., Partap, S. 2014; 116 (3): 617-623

    Abstract

    Magnetic resonance imaging (MRI) is routinely obtained in patients with central nervous system (CNS) tumors, but few studies have been conducted to evaluate this practice. We assessed the benefits of surveillance MRI and more specifically spine MRI in a contemporary cohort. We evaluated MRI results of children diagnosed with CNS tumors from January 2000 to December 2011. Children with at least one surveillance MRI following the diagnosis of medulloblastoma (MB), atypical teratoid rhabdoid tumor (ATRT), pineoblastoma (PB), supratentorial primitive neuroectodermal tumor, supratentorial high-grade glioma (World Health Organization grade III-IV), CNS germ cell tumors or ependymoma were included. A total of 2,707 brain and 1,280 spine MRI scans were obtained in 258 patients. 97 % of all relapses occurred in the brain and 3 % were isolated to the spine. Relapse was identified in 226 (8 %) brain and 48 (4 %) spine MRI scans. The overall rate of detecting isolated spinal relapse was 9/1,000 and 7/1,000 for MB patients. MRI performed for PB showed the highest rate for detecting isolated spinal recurrence with 49/1,000. No initial isolated spinal relapse was identified in patients with glioma, supratentorial primitive neuroectodermal tumor and ATRT. Isolated spinal recurrences are infrequent in children with malignant CNS tumors and the yield of spine MRI is very low. Tailoring surveillance spine MRI to patients with higher spinal relapse risk such as PB, MB with metastatic disease and within 3 years of diagnosis could improve allocation of resources without compromising patient care.

    View details for DOI 10.1007/s11060-013-1347-4

    View details for PubMedID 24401959

  • Relapse patterns in pediatric embryonal central nervous system tumors JOURNAL OF NEURO-ONCOLOGY Perreault, S., Lober, R. M., Carret, A., Zhang, G., Hershon, L., Decarie, J., Yeom, K., Vogel, H., Fisher, P. G., Partap, S. 2013; 115 (2): 209-215

    Abstract

    Embryonal tumors of the central nervous system (CNS) share histological features and were therefore initially grouped as primitive neuroectodermal tumors (PNET) and treated similarly. We sought to determine the relapse patterns of specific embryonal CNS tumors. We conducted a historical cohort study of children diagnosed with CNS embryonal tumors from January 2000 to December 2011 in two pediatric neuro-oncology centers. Patients of 21 years of age or younger at time of presentation with a diagnosis of medulloblastoma, supratentorial PNET, pineoblastoma or atypical teratoid/rhabdoid tumor (ATRT) and at least one surveillance MRI were included. A total of 133 patients met inclusion criteria and 49 (37 %) patients relapsed during the observation period. The majority (79 %) of sPNET relapses were local, whereas all (100 %) PB relapses were associated with diffuse leptomeningeal disease. Relapse patterns for MB were more diverse with local recurrence in 27 %, distant recurrence in 35 % and diffuse leptomeningeal disease in 38 %. The frequency of relapses involving the spine differed (p < 0.001) between tumor types (MB 28/55 [51 %], sPNET 3/33 [9 %], ATRT 3/7 [43 %] and PB 12/12 [100 %]). No sPNET patients had isolated spinal relapse (0/14). Embryonal tumors were found to have divergent patterns of recurrence. While medulloblastoma has variable relapse presentations, sPNET relapses locally and pineoblastoma recurs with diffuse leptomeningeal disease involving the spine. These results point toward possibly new upfront treatment stratification among embryonal tumors in accordance with relapse pattern.

    View details for DOI 10.1007/s11060-013-1213-4

    View details for Web of Science ID 000325821900009

    View details for PubMedID 23921420

  • Increased focal hemosiderin deposition in pediatric medulloblastoma patients receiving radiotherapy at a later age. Journal of neurosurgery. Pediatrics Yeom, K. W., Lober, R. M., Partap, S., Telischak, N., Tsolinas, R., Barnes, P. D., Edwards, M. S. 2013; 12 (5): 444-451

    Abstract

    Object Focal hemosiderin deposition (FHD) is commonly observed on brain MRI scans of patients treated for childhood medulloblastoma (MB). The authors sought to determine the clinical significance of FHD and its relationship to patient age, radiation dose, and cognitive outcomes. Methods A single-institution retrospective study of 93 MB patients at Lucile Packard Children's Hospital at Stanford from 1998 to 2011 identified 41 patients with a negative baseline MRI scan and at least 2 posttreatment MRI scans obtained with T2* gradient recalled echo (GRE). The number and cumulative rate of FHDs detectable by GRE were compared between patients aged 6 years and younger (early age) and aged 7-21 years (late age) at the time of radiotherapy (RT) and between low-dose (1800-2340 cGy) and high-dose (2920-3960 cGy) RT. Results The median age at MB diagnosis was 7.3 years (range 0.9-21.0 years), the median clinical follow-up period was 5.8 years (range 0.8-13.4 years), and the median 5-year overall survival was 81% ± 7%. Of 30 school-aged children with MB, 21 (70%) required special education, and the median IQ of 10 tested patients was 100 (range 50-118). Thirty-three patients (80%) had FHD after a median latency of 1.9 years (range 0.1-5.9 years). Ninety-four percent (436 of 466) of the lesions arose in the supratentorial region of the brain, whereas 29 (6%) resided in the brainstem or the cerebellum. No spinal lesions were observed on routine spine MRI scans using T2 fast spin echo imaging. The mean cumulative lesion rate per year was 2.23 ± 3.05, and this rate was higher in older children at the time of RT compared with younger children (3.23 vs 0.67 per year, p = 0.002) but did not differ among different RT doses (p = 0.395). A child's IQ or need for special education showed no significant correlation with the rate of lesion development or number of lesions. None of the lesions resulted in symptomatic hemorrhage that required surgical intervention. Conclusions More FHD was observed in children treated for MB at the older ages than in those treated at the younger ages. There was no significant association of the incidence of FHD with radiation dose or cognitive outcomes, and none of the lesions required surgical intervention.

    View details for DOI 10.3171/2013.7.PEDS1330

    View details for PubMedID 23992236

  • Histological Predictors of Outcome in Ependymoma are Dependent on Anatomic Site Within the Central Nervous System BRAIN PATHOLOGY Raghunathan, A., Wani, K., Armstrong, T. S., Vera-Bolanos, E., Fouladi, M., Gilbertson, R., Gajjar, A., Goldman, S., Lehman, N. L., Metellus, P., Mikkelsen, T., Necesito-Reyes, M. J., Omuro, A., Packer, R. J., Partap, S., Pollack, I. F., Prados, M. D., Robins, H. I., Soffietti, R., Wu, J., Miller, C. R., Gilbert, M. R., Aldape, K. D. 2013; 23 (5): 584-594

    Abstract

    Ependymomas originate in posterior fossa (PF), supratentorial (ST) or spinal cord (SC) compartments. At present, grading schemes are applied independent of anatomic site. We performed detailed histological examination on 238 World Health Organization grade II and III ependymomas. Among PF ependymomas, the presence of hypercellular areas, necrosis, microvascular proliferation and elevated mitotic rate (all P < 0.01) were significantly associated with worse progression-free survival (PFS), while extensive ependymal canal formation was not (P = 0.89). Similar to the PF tumors, microvascular proliferation (P = 0.01) and elevated mitotic rate (P = 0.03) were significantly associated with worse PFS in the ST tumors. However, in contrast to PF tumors, extensive ependymal canals (P = 0.03) were associated with worse clinical outcome in ST ependymomas, but hypercellularity (P = 0.57) and necrosis (P = 0.47) were not. On multivariate Cox regression, after adjusting for relevant clinical variables, individual histological factors and a composite histological score remained significant among ST and PF ependymoma. In contrast to both PF and ST ependymoma, histological features were not found to be associated with PFS in SC tumors. Taken together, the clinical relevance of specific histological features in ependymoma appears to be related to the anatomic site of origin and suggests that site-specific grading criteria be considered in future classification systems.

    View details for DOI 10.1111/bpa.12050

    View details for Web of Science ID 000329280700009

    View details for PubMedID 23452038

  • Prognostic role for diffusion-weighted imaging of pediatric optic pathway glioma. Journal of neuro-oncology Yeom, K. W., Lober, R. M., Andre, J. B., Fisher, P. G., Barnes, P. D., Edwards, M. S., Partap, S. 2013; 113 (3): 479-483

    Abstract

    Optic pathway glioma (OPG) has an unpredictable course, with poor correlation between conventional imaging features and tumor progression. We investigated whether diffusion-weighted MRI (DWI) predicts the clinical behavior of these tumors. Twelve children with OPG (median age 2.7 years; range 0.4-6.2 years) were followed for a median 4.4 years with DWI. Progression-free survival (time to requiring therapy) was compared between tumors stratified by apparent diffusion coefficient (ADC) from initial pre-treatment scans. Tumors with baseline ADC greater than 1,400 × 10(-6) mm(2)/s required treatment earlier than those with lower ADC (log-rank p = 0.002). In some cases, ADC increased leading up to treatment, and declined following treatment with surgery, chemotherapy, or radiation. Baseline ADC was higher in tumors that eventually required treatment (1,562 ± 192 × 10(-6) mm(2)/s), compared with those conservatively managed (1,123 ± 114 × 10(-6) mm(2)/s) (Kruskal-Wallis test p = 0.013). Higher ADC predicted earlier tumor progression in this cohort and in some cases declined after therapy. Evaluation of OPG with DWI may therefore be useful for predicting tumor behavior and assessing treatment response.

    View details for DOI 10.1007/s11060-013-1140-4

    View details for PubMedID 23673514

  • Distinctive MRI Features of Pediatric Medulloblastoma Subtypes AMERICAN JOURNAL OF ROENTGENOLOGY Yeom, K. W., Mobley, B. C., Lober, R. M., Andre, J. B., Partap, S., Vogel, H., Barnes, P. D. 2013; 200 (4): 895-903

    Abstract

    We hypothesized that the apparent diffusion coefficient (ADC) and other MRI features can be used to predict medulloblastoma histologic subtypes, as defined by the World Health Organization (WHO) in WHO Classification of Tumours of the Central Nervous System.A retrospective review of pediatric patients with medulloblastoma between 1989 and 2011 identified 38 patients with both pretreatment MRI and original pathology slides. The mean and minimum tumor ADC values and conventional MRI features were compared among medulloblastoma histologic subtypes.The cohort of 38 patients included the following histologic subtypes: 24 classic medulloblastomas, nine large cell (LC) or anaplastic medulloblastomas, four desmoplastic medulloblastomas, and one medulloblastoma with extensive nodularity. The median age at diagnosis was 8 years (range, 1-21 years) and the median follow-up time was 33 months (range, 0-150 months). The mean ADC (× 10(-3) mm(2)/s) was lower in classic medulloblastoma (0.733 ± 0.046 [SD]) than in LC or anaplastic medulloblastoma (0.935 ± 0.127) (Mann-Whitney test, p = 0.004). Similarly, the minimum ADC was lower in classic medulloblastoma (average ± SD, 0.464 ± 0.056) than in LC or anaplastic medulloblastoma (0.630 ± 0.053) (p = 0.004). The MRI finding of focal cysts correlated with the classic and desmoplastic subtypes (Fisher exact test, p = 0.026). Leptomeningeal enhancement positively correlated with the LC or anaplastic medulloblastoma subtype and inversely correlated with the classic medulloblastoma and desmoplastic medulloblastoma subtypes (p = 0.04). Ring enhancement correlated with tumor necrosis (p = 0.022) and with the LC or anaplastic medulloblastoma histologic subtype (p < 0.001).The LC or anaplastic medulloblastoma subtype was associated with increased ADC and with ring enhancement, the latter of which correlated with tumor necrosis. These features could be considered in the evaluation of high-risk medulloblastoma subtypes.

    View details for DOI 10.2214/AJR.12.9249

    View details for Web of Science ID 000316622100045

    View details for PubMedID 23521467

  • Concurrent cyclophosphamide and craniospinal radiotherapy for pediatric high-risk embryonal brain tumors JOURNAL OF NEURO-ONCOLOGY Campen, C. J., Dearlove, J., Partap, S., Murphy, P., Gibbs, I. C., Dahl, G. V., Fisher, P. G. 2012; 110 (2): 287-291

    Abstract

    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

  • Stroke and Cerebrovascular Complications in Childhood Cancer Survivors SEMINARS IN PEDIATRIC NEUROLOGY Partap, S. 2012; 19 (1): 18-24

    Abstract

    The outcomes for childhood cancer have drastically improved over the last several decades. Previously, irradiation was commonly used for blood-borne (leukemia, lymphoma) cancers and neck and brain tumors. Radiation therapy remains the mainstay of treatment for highly malignant cancers of head and neck and for some primary central nervous system tumors. Unfortunately, radiation therapy has been implicated as a contributor to many late effects of treatment, including cerebrovascular disease from large-vessel vascular injury, stroke, moyamoya, mineralizing microangiopathy, to stroke-like migraine. This review summarizes the pathophysiology of these disorders in relationship to treatment with and without radiation as well as the relevant manifestations of radiation-induced cerebrovascular disease. Patient populations at highest risk and current recommendations for health providers and patient education are emphasized when possible.

    View details for DOI 10.1016/j.spen.2012.02.012

    View details for Web of Science ID 000305263900004

    View details for PubMedID 22641072

  • Liposomal cytarabine for central nervous system embryonal tumors in children and young adults JOURNAL OF NEURO-ONCOLOGY Partap, S., Murphy, P. A., Vogel, H., Barnes, P. D., Edwards, M. S., Fisher, P. G. 2011; 103 (3): 561-566

    Abstract

    To assess the tolerability and efficacy of liposomal cytarabine (LC), an encapsulated, sustained-release, intrathecal (IT) formulation of cytosine arabinoside, in de novo and relapsed central nervous system (CNS) embryonal tumors in children and young adults. We studied retrospectively all patients less than age 30 at our institution treated consecutively with LC for medulloblastoma (MB), primitive neuroectodermal tumor (PNET), and atypical teratoid rhabdoid tumor (ATRT). Seventeen patients received LC (2 mg/kg up to 50 mg, every 2 weeks to monthly) at diagnosis of high-risk CNS embryonal tumor (2 PNET, 3 ATRT) or relapse of MB (12 MB; 9 had leptomeningeal metastases). Sixteen patients received concurrent systemic chemotherapy. A total of 108 doses were administered (IT 82, intraventricular 26) with a mean of six (range 1-16) treatments per patient. Only three administrations were associated with adverse effects of arachnoiditis or headache. None developed malignant cerebrospinal fluid (CSF) cytology while receiving LC. All the six evaluable patients with malignant CSF cytology and treated with at least two doses cleared their CSF (mean 3 doses, range 1-5). Median overall survival in relapse patients was 9.1 months. Five patients (4 de novo and 1 relapsed) remain alive in complete remission for a median 26.8 months from first LC. Liposomal cytarabine is an easily administered, well-tolerated, and active drug in patients with high-risk embryonal neoplasms. One-third of our cohort remains in remission from otherwise fatal diagnoses. Our findings warrant a phase II trial of LC in newly diagnosed or recurrent CNS embryonal tumors.

    View details for DOI 10.1007/s11060-010-0419-y

    View details for Web of Science ID 000291703000018

    View details for PubMedID 20859651

  • Effect of chronic red cell transfusion therapy on vasculopathies and silent infarcts in patients with sickle cell disease AMERICAN JOURNAL OF HEMATOLOGY Gyang, E., Yeom, K., Hoppe, C., Partap, S., Jeng, M. 2011; 86 (1): 104-106

    Abstract

    Regular, chronic red cell transfusions (CTX) have been shown to be effective prophylaxis against stroke in sickle cell disease (SCD) in those at risk. Because serial brain imaging is not routinely performed, little is known about the impact of CTX on silent infarcts (SI) and cerebral vascular pathology. Thus, we retrospectively evaluated the magnetic resonance imaging reports of a cohort of SCD patients who were prescribed CTX for either primary or secondary stroke prophylaxis. Seventeen patients with Hb SS were included (mean age 15 years, mean follow-up 4.3 years). Eight patients were on CTX for primary prophylaxis. New SI occurred in 17.6% of patients corresponding to an SI rate of 5.42 per 100 patient-years. Vasculopathy of the cerebral arteries was present in 65% of patients and progressed in 63% of these patients. Those who developed progressive vasculopathy were on CTX for an average of 8 years before lesions progressed. Patients on CTX for secondary prophylaxis had more SIs and evidence of progressive vascular disease than patients on CTX for primary prophylaxis. We conclude that adherence to CTX does not necessarily prevent SI or halt cerebral vasculopathy progression, especially in those with a history of overt stroke.

    View details for DOI 10.1002/ajh.21901

    View details for Web of Science ID 000285421300025

    View details for PubMedID 21117059

  • Birth Weight and Order as Risk Factors for Childhood Central Nervous System Tumors JOURNAL OF PEDIATRICS Maclean, J., Partap, S., Reynolds, P., Von Behren, J., Fisher, P. G. 2010; 157 (3): 450-455

    Abstract

    To determine whether birth characteristics related to maternal-fetal health in utero are associated with the development of childhood central nervous system tumors.We identified, from the California Cancer Registry, 3733 children under age 15 diagnosed with childhood central nervous system tumors between 1988 and 2006 and linked these cases to their California birth certificates. Four controls per case, matched on birth date and sex, were randomly selected from the same birth files. We evaluated associations of multiple childhood CNS tumor subtypes with birth weight and birth order.Low birth weight was associated with a reduced risk of low-grade gliomas (OR=0.67; 95% CI, 0.46 to 0.97) and high birth weight was associated with increased risk of high-grade gliomas (OR=1.57; 95% CI, 1.16 to 2.12). High birth order (fourth or higher) was associated with decreased risk of low-grade gliomas (OR=0.75; 95% CI, 0.56 to 0.99) and increased risk of high-grade gliomas (OR=1.32; 95% CI, 1.01 to 1.72 for second order).Factors that drive growth in utero may increase the risk of low-grade gliomas. There may be a similar relationship in high-grade gliomas, although other factors, such as early infection, may modify this association. Additional investigation is warranted to validate and further define these findings.

    View details for DOI 10.1016/j.jpeds.2010.04.006

    View details for Web of Science ID 000281116100023

    View details for PubMedID 20553692

  • Medulloblastoma Incidence has not Changed Over Time A CBTRUS Study JOURNAL OF PEDIATRIC HEMATOLOGY ONCOLOGY Partap, S., Curran, E. K., Propp, J. M., Le, G. M., Sainani, K. L., Fisher, P. G. 2009; 31 (12): 970-971

    Abstract

    Earlier studies have reported changes in the incidence of medulloblastoma (MB) but have conflicted, likely because of small sample size or misclassification of MB with primitive neuroectodermal tumor (PNET). The incidence of MB and PNET from 1985 to 2002 was determined from the Central Brain Tumor Registry of the United States, a large population-based cancer registry, using strict histologic and site codes. No statistically significant change in MB incidence was observed over the last 2 decades, but there was an increase in MB and PNET combined.

    View details for Web of Science ID 000272658700019

    View details for PubMedID 19887963

  • Levetiracetam For Seizures in Children With Brain Tumors and Other Cancers PEDIATRIC BLOOD & CANCER Partap, S., Fisher, P. G. 2009; 52 (2): 288-289

    Abstract

    Children with brain tumors and other cancers can suffer from seizures. Unfortunately, most antiepileptic therapies are metabolized by the hepatic cytochrome P450 (CYP) system. Levetiracetam, a newer anticonvulsant, does not undergo CYP metabolism and does not alter the pharmacokinetics of chemotherapy, antiemetics, and corticosteroids, which are metabolized by the liver. We studied 23 patients with cancer and seizures treated with levetiracetam. Over 95% of patients had fewer seizures, with 65.2% becoming seizure free; only one patient experienced an adverse reaction. Levetiracetam is effective and well tolerated in children with brain tumors and other cancers, who are often on multiple enzyme-inducing drugs.

    View details for DOI 10.1002/pbc.21772

    View details for Web of Science ID 000261796000032

    View details for PubMedID 18831033

  • Neurological complications in children. Cancer treatment and research Partap, S., Fisher, P. G. 2009; 150: 133-143

    View details for DOI 10.1007/b109924_9

    View details for PubMedID 19834666

  • Update on new treatments and developments in childhood brain tumors CURRENT OPINION IN PEDIATRICS Partap, S., Fisher, P. G. 2007; 19 (6): 670-674

    Abstract

    Childhood primary central nervous system tumors remain a therapeutic conundrum. As the second most common pediatric cancer, brain tumors lead to significantly worse survival and long-term effects compared with those seen with hematologic malignancies and other solid tumors. This review discusses current management strategies in three pediatric brain tumors, the long-term effects of therapy, as well as novel laboratory findings that may alter future treatment strategies.The current literature focuses on tactics to predict those at risk of treatment failure and long-term effects. By analyzing tumors at a molecular genetics level rather than traditional histology, new data have begun to emerge on methods to begin to consider targeted therapies, tailored to the individual child. Furthermore, as survivorship has improved with current radiation and chemotherapy regimens, long-term effects have been identified and merit clinical attention.Even though long-term survival for children with a brain tumor approaches 70%, the need for improved treatment regimens is striking. Secondary malignancies, neurocognitive deficits and treatment failure continue to afflict these children and young adults. The current review will inform clinicians of the challenges faced by basic scientists and clinicians when treating brain tumors, and point to future research directions.

    View details for Web of Science ID 000251347800010

    View details for PubMedID 18025934

  • 50 Years Ago in The Journal of Pediatrics: Low cerebrospinal fluid glucose associated with meningeal neoplasia JOURNAL OF PEDIATRICS Partap, S. 2007; 151 (2): 177
  • 50 Years Ago in The Journal of Pediatrics: Agenesis of the corpus callosum: report of eight cases in infancy. JOURNAL OF PEDIATRICS Partap, S. 2007; 150 (4): 399
  • Spontaneously relapsing and remitting primary CNS lymphoma in an immunocompetent 45-year-old man JOURNAL OF NEURO-ONCOLOGY Partap, S., Spence, A. M. 2006; 80 (3): 305-307

    Abstract

    A 45-year-old immunocompetent man with primary central nervous system lymphoma (PCNSL) presented with multiple spontaneous relapses and remissions in the absence of steroid treatment. Because of the fluctuations with improvement in both the clinical course and MRI findings, alternative disorders were considered that led to delay of diagnosis and treatment prior to brain biopsy. This case and a handful of others with single remissions emphasize that PCNSL cannot be reliably ruled out by improving or disappearing symptoms, signs or traditional MR imaging abnormalities.

    View details for DOI 10.1007/s11060-006-9192-3

    View details for Web of Science ID 000243002600011

    View details for PubMedID 16794747

  • Complications of a temozolomide overdose: a case report JOURNAL OF NEURO-ONCOLOGY Spence, A. M., Kiem, H., Partap, S., Schuetze, S., Silber, J. R., Peterson, R. A. 2006; 80 (1): 57-61

    Abstract

    This is a report of a 53 year-old man with a glioblastoma multiforme (GBM) treated with an excessive dose of temozolomide (TMZ).This is a single case review of all clinically relevant records. O6-methylguanine-DNA methyltransferase activity was determined by a biochemical assay.Following conventional radiotherapy (RT) without concurrent chemotherapy, the patient received 5,500 mg of TMZ over 2 days. At the standard dose of 200 mg/m2/day his total 5-day dose should have been 1,940 mg. Acutely he had nausea, vomiting and diarrhea for 2 days which cleared. The dominant severe toxicity was pancytopenia between one and four weeks after TMZ which was complicated by secondary infections that were successfully managed. Transient transaminitis occurred but there were no significant pulmonary, renal or other systemic toxicities. His progression free survival was 22 months and overall survival 24 months.His outcome suggests that TMZ may prove to be a good agent for dose-escalation trials with hematopoietic stem cell rescue.

    View details for DOI 10.1007/s11060-006-9152-y

    View details for Web of Science ID 000240802300009

    View details for PubMedID 16645714

  • Prolonged but reversible migraine-like episodes long after cranial irradiation NEUROLOGY Partap, S., Walker, M., Longstreth, W. T., Spence, A. M. 2006; 66 (7): 1105-1107

    Abstract

    The authors describe three patients with prolonged but reversible episodes of severe headaches and focal neurologic deficits developing years after irradiation for cranial neoplasms. Despite extensive evaluations, etiology of episodes in these three and eight other previously reported patients remains undetermined. Whether they all have the same condition is uncertain. Although some had cortical gadolinium enhancement on MRI, all 11 patients returned to baseline over hours to weeks.

    View details for Web of Science ID 000236673300030

    View details for PubMedID 16606929

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