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Malik JR, Podany AT, Khan P, Shaffer CL, Siddiqui JA, Baranowska‐Kortylewicz J, Le J, Fletcher CV, Ether SA, Avedissian SN. Chemotherapy in pediatric brain tumor and the challenge of the blood-brain barrier. Cancer Med 2023; 12:21075-21096. [PMID: 37997517 PMCID: PMC10726873 DOI: 10.1002/cam4.6647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 09/18/2023] [Accepted: 10/12/2023] [Indexed: 11/25/2023] Open
Abstract
BACKGROUND Pediatric brain tumors (PBT) stand as the leading cause of cancer-related deaths in children. Chemoradiation protocols have improved survival rates, even for non-resectable tumors. Nonetheless, radiation therapy carries the risk of numerous adverse effects that can have long-lasting, detrimental effects on the quality of life for survivors. The pursuit of chemotherapeutics that could obviate the need for radiotherapy remains ongoing. Several anti-tumor agents, including sunitinib, valproic acid, carboplatin, and panobinostat, have shown effectiveness in various malignancies but have not proven effective in treating PBT. The presence of the blood-brain barrier (BBB) plays a pivotal role in maintaining suboptimal concentrations of anti-cancer drugs in the central nervous system (CNS). Ongoing research aims to modulate the integrity of the BBB to attain clinically effective drug concentrations in the CNS. However, current findings on the interaction of exogenous chemical agents with the BBB remain limited and do not provide a comprehensive explanation for the ineffectiveness of established anti-cancer drugs in PBT. METHODS We conducted our search for chemotherapeutic agents associated with the blood-brain barrier (BBB) using the following keywords: Chemotherapy in Cancer, Chemotherapy in Brain Cancer, Chemotherapy in PBT, BBB Inhibition of Drugs into CNS, Suboptimal Concentration of CNS Drugs, PBT Drugs and BBB, and Potential PBT Drugs. We reviewed each relevant article before compiling the information in our manuscript. For the generation of figures, we utilized BioRender software. FOCUS We focused our article search on chemical agents for PBT and subsequently investigated the role of the BBB in this context. Our search criteria included clinical trials, both randomized and non-randomized studies, preclinical research, review articles, and research papers. FINDING Our research suggests that, despite the availability of potent chemotherapeutic agents for several types of cancer, the effectiveness of these chemical agents in treating PBT has not been comprehensively explored. Additionally, there is a scarcity of studies examining the role of the BBB in the suboptimal outcomes of PBT treatment, despite the effectiveness of these drugs for other types of tumors.
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Affiliation(s)
- Johid Reza Malik
- Antiviral Pharmacology LaboratoryCollege of Pharmacy, University of Nebraska Medical CenterOmahaNebraskaUSA
| | - Anthony T. Podany
- Antiviral Pharmacology LaboratoryCollege of Pharmacy, University of Nebraska Medical CenterOmahaNebraskaUSA
- Pediatric Clinical Pharmacology ProgramChild Health Research Institute, University of Nebraska Medical CenterOmahaNebraskaUSA
| | - Parvez Khan
- Department of Biochemistry and Molecular BiologyUniversity of Nebraska Medical CenterOmahaNebraskaUSA
| | - Christopher L. Shaffer
- Pediatric Clinical Pharmacology ProgramChild Health Research Institute, University of Nebraska Medical CenterOmahaNebraskaUSA
| | - Jawed A. Siddiqui
- Department of Biochemistry and Molecular BiologyUniversity of Nebraska Medical CenterOmahaNebraskaUSA
| | | | - Jennifer Le
- University of California San Diego Skaggs School of Pharmacy and Pharmaceutical SciencesSan DiegoCaliforniaUSA
| | - Courtney V. Fletcher
- Antiviral Pharmacology LaboratoryCollege of Pharmacy, University of Nebraska Medical CenterOmahaNebraskaUSA
| | - Sadia Afruz Ether
- Antiviral Pharmacology LaboratoryCollege of Pharmacy, University of Nebraska Medical CenterOmahaNebraskaUSA
| | - Sean N. Avedissian
- Antiviral Pharmacology LaboratoryCollege of Pharmacy, University of Nebraska Medical CenterOmahaNebraskaUSA
- Pediatric Clinical Pharmacology ProgramChild Health Research Institute, University of Nebraska Medical CenterOmahaNebraskaUSA
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Tomita T. The evolution of pediatric neurosurgery: reflection of personal experience of the last half-century. Childs Nerv Syst 2023; 39:2571-2582. [PMID: 37486438 DOI: 10.1007/s00381-023-06068-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Accepted: 07/05/2023] [Indexed: 07/25/2023]
Abstract
OBJECTIVES In the past 50 years, pediatric neurosurgery has made tremendous strides, and gained its own identity as a distinct subspecialty. I have personally observed this progress and evolution in pediatric neurosurgery in multiple dimensions, which are described based upon my own experience and reflection. METHODS The development and evolutions of multiple domains of pediatric neurosurgery, including neuroimaging, hydrocephalus, pediatric brain tumor, spinal dysraphism, craniosynostosis, vascular malformation, functional neurosurgery and spinal disorders were reviewed and commented on based upon my own experience and reflection. RESULTS The field of pediatric neurosurgery has grown in all aspects of diagnosis and therapy owing to the introduction of computers, innovative techniques and technologies and new discoveries of scientific data including molecular investigations. CONCLUSION A minimally invasive approach and molecular target therapy are a current trend. The past half century's clinical experience and advances in biomedical knowledge and techniques provide foundation for further improvement in the care of children of the next generation. Prospective artificial intelligence will likely promote further advances in pediatric neurosurgery.
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Affiliation(s)
- Tadanori Tomita
- Division of Pediatric Neurosurgery, Department of Neurological Surgery, Ann & Robert H. Lurie Children's Hospital of Chicago, Northwestern University Feinberg School of Medicine, 225 E. Chicago Avenue, Chicago, Illinois, 60611, USA.
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Apps JR, Maycock S, Ellison DW, Jaspan T, Ritzmann TA, Macarthur D, Mallucci C, Wheatley K, Veal GJ, Grundy RG, Picton S. Phase II study of intravenous etoposide in patients with relapsed ependymoma (CNS 2001 04). Neurooncol Adv 2022; 4:vdac053. [PMID: 35591977 PMCID: PMC9113139 DOI: 10.1093/noajnl/vdac053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Background Relapsed ependymoma has a dismal prognosis, and the role of chemotherapy at relapse remains unclear. This study prospectively evaluated the efficacy of intensive intravenous (IV) etoposide in patients less than 21 years of age with relapsed intracranial ependymoma (NCT00278252). Methods This was a single-arm, open-label, phase II trial using Gehan's two-stage design. Patients received IV etoposide 100 mg/m2 on days 1-3, 8-10, and 15-17 of each 28-day cycle, up to maximum of 6 cycles. Primary outcome was radiological response after 3 cycles. Pharmacokinetic analysis was performed in 10 patients. Results Twenty-five patients were enrolled and included in the intention-to-treat (ITT) analysis. Three patients were excluded in per-protocol (PP) analysis. After 3 cycles of etoposide, 5 patients (ITT 20%/PP 23%) had a complete response (CR), partial response (PR), or objective response (OR). Nine patients (ITT 36%/PP 41%,) had a best overall response of CR, PR, or OR. 1-year PFS was 24% in ITT and 23% in PP populations. 1-year OS was 56% and 59%, 5-year OS was 20% and 18%, respectively, in ITT and PP populations. Toxicity was predominantly hematological, with 20/25 patients experiencing a grade 3 or higher hematological adverse event. Conclusions This study confirms the activity of IV etoposide against relapsed ependymoma, however, this is modest, not sustained, and similar to that with oral etoposide, albeit with increased toxicity. These results confirm the dismal prognosis of this disease, provide a rationale to include etoposide within drug combinations, and highlight the need to develop novel treatments for recurrent ependymoma.
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Affiliation(s)
- John R Apps
- Cancer Research UK Clinical Trials Unit, University of Birmingham, Birmingham, UK
| | - Shanna Maycock
- Cancer Research UK Clinical Trials Unit, University of Birmingham, Birmingham, UK
| | - David W Ellison
- Department of Pathology, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - Timothy Jaspan
- Radiology Department, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - Timothy A Ritzmann
- Children’s Brain Tumour Research Centre, Bio-Discovery Institute and Queen’s Medical Centre, University of Nottingham, Nottingham, UK
| | - Donald Macarthur
- Children’s Brain Tumour Research Centre, Bio-Discovery Institute and Queen’s Medical Centre, University of Nottingham, Nottingham, UK
| | - Conor Mallucci
- Department of Neurosurgery, Alder Hey Children’s NHS Foundation Trust, Liverpool, UK
| | - Keith Wheatley
- Cancer Research UK Clinical Trials Unit, University of Birmingham, Birmingham, UK
| | - Gareth J Veal
- Newcastle University Centre for Cancer, Newcastle University, Newcastle upon Tyne, UK
| | - Richard G Grundy
- Children’s Brain Tumour Research Centre, Bio-Discovery Institute and Queen’s Medical Centre, University of Nottingham, Nottingham, UK
| | - Susan Picton
- Department of Paediatric Oncology, Leeds Children’s Hospital, The Leeds Teaching Hospitals NHS Trust, Leeds, UK
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Abemaciclib, A Selective CDK4/6 Inhibitor, Restricts the Growth of Pediatric Ependymomas. Cancers (Basel) 2020; 12:cancers12123597. [PMID: 33271970 PMCID: PMC7760843 DOI: 10.3390/cancers12123597] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 11/29/2020] [Indexed: 12/12/2022] Open
Abstract
Simple Summary Pediatric ependymomas are malignant pediatric brain tumors, and one-third of patients exhibit recurrence within two years of initial treatment. Therefore, this study aimed to find new agents to overcome these chemoresistant tumors and defer radiotherapy treatment. By using integrated bioinformatics and experimental validation, we demonstrated that abemaciclib, a CDK4/6 inhibitor, effectively inhibited cell proliferation and induced cell death. Therefore, treatment with abemaciclib showed encouraging results in preclinical pediatric ependymoma models and provide a new therapeutic strategy in the future. Abstract Pediatric ependymomas are a type of malignant brain tumor that occurs in children. The overall 10-year survival rate has been reported as being 45–75%. Maximal safe surgical resection combined with adjuvant chemoradiation therapy is associated with the highest overall and progression-free survival rates. Despite aggressive treatment, one-third of ependymomas exhibit recurrence within 2 years of initial treatment. Therefore, this study aimed to find new agents to overcome chemoresistance and defer radiotherapy treatment since, in addition, radiation exposure may cause long-term side effects in the developing brains of young children. By using integrated bioinformatics and through experimental validation, we found that at least one of the genes CCND1 and CDK4 is overexpressed in ependymomas. The use of abemaciclib, a highly selective CDK4/6 inhibitor, effectively inhibited cell proliferation and reduced the expression of cell-cycle-related and DNA-repair-related gene expression via the suppression of RB phosphorylation, which was determined through RNA-seq and Western blot analyses. Furthermore, abemaciclib effectively induced cell death in vitro. The efficiency of abemaciclib was validated in vivo using subcutaneously implanted ependymoma tissues from patient-derived xenografts (PDXs) in mouse models. Treatment with abemaciclib showed encouraging results in preclinical pediatric ependymoma models and represents a potential therapeutic strategy for treating challenging tumors in children.
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Overview of Current Drug Delivery Methods Across the Blood-Brain Barrier for the Treatment of Primary Brain Tumors. CNS Drugs 2020; 34:1121-1131. [PMID: 32965590 PMCID: PMC7658069 DOI: 10.1007/s40263-020-00766-w] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/05/2020] [Indexed: 01/05/2023]
Abstract
Existing drug delivery methods have not led to a significant increase in survival for patients with malignant primary brain tumors. While the combination of conventional therapies consisting of surgery, radiotherapy, and chemotherapy has improved survival for some types of brain tumors (e.g., WNT medulloblastoma), other types of brain tumors (e.g., glioblastoma and diffuse midline glioma) still have a poor prognosis. The reason for the differences in response can be largely attributed to the blood-brain barrier (BBB), a specialized structure at the microvasculature level that regulates the transport of molecules across the blood vessels into the brain parenchyma. This structure hampers the delivery of most chemotherapeutic agents for the treatment of primary brain tumors. Several drug delivery methods such as nanoparticles, convection enhanced delivery, focused ultrasound, intranasal delivery, and intra-arterial delivery have been developed to overcome the BBB in primary brain tumors. However, prognosis of most primary brain tumors still remains poor. The heterogeneity of the BBB in primary brain tumors and the distinct vasculature of tumors make it difficult to design a drug delivery method that targets the entire tumor. Drug delivery methods that combine strategies such as focused ultrasound and nanoparticles might be a more successful approach. However, more research is needed to optimize and develop new drug delivery techniques to improve survival of patients with primary brain tumors.
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Mathis SE, Alberico A, Nande R, Neto W, Lawrence L, McCallister DR, Denvir J, Kimmey GA, Mogul M, Oakley G, Denning KL, Dougherty T, Valluri JV, Claudio PP. Chemo-predictive assay for targeting cancer stem-like cells in patients affected by brain tumors. PLoS One 2014; 9:e105710. [PMID: 25144312 PMCID: PMC4140819 DOI: 10.1371/journal.pone.0105710] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 07/23/2014] [Indexed: 11/18/2022] Open
Abstract
Administration of ineffective anticancer therapy is associated with unnecessary toxicity and development of resistant clones. Cancer stem-like cells (CSLCs) resist chemotherapy, thereby causing relapse of the disease. Thus, development of a test that identifies the most effective chemotherapy management offers great promise for individualized anticancer treatments. We have developed an ex vivo chemotherapy sensitivity assay (ChemoID), which measures the sensitivity of CSLCs as well as the bulk of tumor cells to a variety of chemotherapy agents. Two patients, a 21-year old male (patient 1) and a 5-month female (patient 2), affected by anaplastic WHO grade-III ependymoma were screened using the ChemoID assay. Patient 1 was found sensitive to the combination of irinotecan and bevacizumab, which resulted in a prolonged disease progression free period of 18 months. Following recurrence, the combination of various chemotherapy drugs was tested again with the ChemoID assay. We found that benzyl isothiocyanate (BITC) greatly increased the chemosensitivity of the ependymoma cells to the combination of irinotecan and bevacizumab. After patient 1 was treated for two months with irinotecan, bevacizumab and supplements of cruciferous vegetable extracts containing BITC, we observed over 50% tumoral regression in comparison with pre-ChemoID scan as evidenced by MRI. Patient 2 was found resistant to all treatments tested and following 6 cycles of vincristine, carboplatin, cyclophosphamide, etoposide, and cisplatin in various combinations, the tumor of this patient rapidly progressed and proton beam therapy was recommended. As expected animal studies conducted with patient derived xenografts treated with ChemoID screened drugs recapitulated the clinical observation. This assay demonstrates that patients with the same histological stage and grade of cancer may vary considerably in their clinical response, suggesting that ChemoID testing which measures the sensitivity of CSLCs as well as the bulk of tumor cells to a variety of chemotherapy agents could lead to more effective and personalized anticancer treatments in the future.
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Affiliation(s)
- Sarah E. Mathis
- Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, United States of America
- Translational Genomic Research Institute, Marshall University, Huntington, West Virginia, United States of America
| | - Anthony Alberico
- Department of Neurosurgery, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, United States of America
| | - Rounak Nande
- Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, United States of America
- Translational Genomic Research Institute, Marshall University, Huntington, West Virginia, United States of America
| | - Walter Neto
- Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, United States of America
- Translational Genomic Research Institute, Marshall University, Huntington, West Virginia, United States of America
| | - Logan Lawrence
- Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, United States of America
- Translational Genomic Research Institute, Marshall University, Huntington, West Virginia, United States of America
| | - Danielle R. McCallister
- Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, United States of America
- Translational Genomic Research Institute, Marshall University, Huntington, West Virginia, United States of America
| | - James Denvir
- Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, United States of America
- Translational Genomic Research Institute, Marshall University, Huntington, West Virginia, United States of America
| | - Gerrit A. Kimmey
- Department of Medical Oncology, St. Mary's Hospital, Huntington, West Virginia, United States of America
| | - Mark Mogul
- Department of Pediatrics, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, United States of America
| | - Gerard Oakley
- Department of Pathology, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, United States of America
| | - Krista L. Denning
- Department of Pathology, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, United States of America
| | - Thomas Dougherty
- Department of Pathology, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, United States of America
| | - Jagan V. Valluri
- Department of Biology, Marshall University, Huntington, West Virginia, United States of America
| | - Pier Paolo Claudio
- Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, United States of America
- Translational Genomic Research Institute, Marshall University, Huntington, West Virginia, United States of America
- Department of Surgery, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, United States of America
- * E-mail:
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Tomita T. Pediatric neurosurgery-science, art, and humility: reflection of personal experience. Childs Nerv Syst 2013; 29:1403-14. [PMID: 24013313 PMCID: PMC3766518 DOI: 10.1007/s00381-013-2157-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 05/08/2013] [Indexed: 10/26/2022]
Affiliation(s)
- Tadanori Tomita
- Division of Pediatric Neurosurgery, Ann & Robert H. Lurie Children's Hospital of Chicago, IL 60611-2605, USA.
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Abstract
INTRODUCTION The ependymomas are relatively not a common tumor. However, most clinicians agree that the radical removal of the tumor is the most important prognostic factor. MORBIDITY OF TREATMENT Tumor removal was not sufficient before the era of magnetic resonance imaging (MRI) and resulted in a considerable operative morbidity and mortality. As the microneurosurgical techniques and microsurgical anatomy become popular and the MRI provide more detailed anatomical information preoperatively, radical removal of this complex and complicated tumor can be more feasible. In childhood ependymoma, the treatment-related morbidity and mortality can be the special issues, which can modify the policy of management safe tumor removal and minimal adjuvant treatment, which are extremely important. RADIATION THERAPY Radiation treatment has been the option for disseminated disease and residual tumor. With the advancement of detailed MR anatomical information, safer and more delicate radiation becomes possible with newer radiation modalities, three-dimensional conformal radiotherapy, intensity modulating radiotherapy, and tomotherapy. PROGNOSTIC FACTORS Although many clinicians believe that the ependymomas are inheritably chemoresistant, the new targets for the treatment are under investigation or clinically tried. Also, the genetic alterations of ependymoma are developing and might be a promising target. CONCLUSION The surgical techniques and assistant modalities for tumor removal are still advancing. So, the outcome of ependymoma is still improving. Unfortunately, newer treatment modalities, such as new chemotherapeutic agent and gene modification agent, are still not promising. The history of ependymoma management is still in progress.
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Affiliation(s)
- Kyu-Won Shim
- Department of Pediatric Neurosurgery, Severance Children's Hospital, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
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Merchant TE, Fouladi M. Ependymoma: new therapeutic approaches including radiation and chemotherapy. J Neurooncol 2006; 75:287-99. [PMID: 16195801 DOI: 10.1007/s11060-005-6753-9] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Recent advances in neuroimaging, neurosurgery and radiation therapy have improved disease control and functional outcomes for children with ependymoma, including children under the age of 3 years. The rate of gross-total resection has been increased to 85% in some series and 3 year progression-free survival after radiation therapy as high as 75% has been reported along with significant reductions in neurologic, endocrine and cognitive deficits. Based on these advances and renewed interest in radiation therapy as a frontline treatment modality, attention has been refocused on disease control instead of radiotherapy avoidance. Future research in the treatment of this tumor, that afflicts fewer than 200 children in the US each year, will focus on molecular biology, clarifying risk factors for tumor control and late effects, and testing novel agents.
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Affiliation(s)
- Thomas E Merchant
- Division of Radiation Oncology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
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Abstract
Childhood intracranial ependymoma have a dismal prognosis, especially in young children and when a gross total resection cannot be performed. Even in the absence of a radiologically proven residuum, around two-thirds of these young children will have a recurrence. Adjuvant therapy is therefore necessary for most, if not all, patients. Despite some indication that benign ependymoma (WHO grade II) could show a better outcome, histology cannot be used at present to stratify treatment protocols.Craniospinal irradiation combined with posterior fossa boost has deleterious adverse effects on cognition. Consequently, pediatric oncology teams have, firstly, tried to use chemotherapy to delay or avoid irradiation, and secondly, progressively reduced irradiation fields to the tumor bed without altering the prognosis. Cisplatin, at a dose of 120 mg/m(2) (cumulated response rate of 34% [95% CI 19-54%]) is the only single agent that has reproducibly shown some efficacy in ependymoma. Despite some combinations showing efficacy in the adjuvant setting, childhood intracranial ependymomas can, in general, be considered as chemoresistant. The overexpression of the multidrug resistance-1 gene and the 06-methylguanine-DNA methyltransferase have been implicated as possible mechanisms for this phenomenon. As the use of chemotherapy with current agents is questionable, phase II studies with new agents and combinations are necessary. Since the main problem of this disease is local relapse, it may not be necessary to irradiate the whole posterior fossa. However, local control of the disease by irradiation has to be improved. In this respect, hyperfractionation or radiosensitizers may be valuable therapeutic options. The treatment of children with ependymoma is a challenge for all caregivers. There is no doubt that any possible improvement in the management of this rare tumor will only be the result of well designed cooperative trials.
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Affiliation(s)
- Jacques Grill
- Department of Pediatric Oncology, Institut Gustave Roussy, Villejuif, France.
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Abstract
Conventional therapies such as surgery, radiotherapy and, to a lesser extent, chemotherapy have produced significant increases in survival in patients with some types of brain tumours such as medulloblastoma. However, in many other types of brain tumour in both adults and children, the effect of these modalities has been more modest. A thorough understanding of the biology of malignant brain tumours is likely to provide the background for the development of new leads that might be amenable to therapeutic exploitation. This review examines some aspects of glioma biology that have been reported in the past 12 months, and which might be translated into clinical application.
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Affiliation(s)
- J L Darling
- University Department of Neurosurgery, Institute of Neurology, National Hospital for Neurology and Neurosurgery, London, UK
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