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1.
Front Oncol ; 14: 1296576, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38357205

RESUMO

Background: The survival for many children with relapsed/refractory cancers remains poor despite advances in therapies. Arginine metabolism plays a key role in the pathophysiology of a number of pediatric cancers. We report the first in child study of a recombinant human arginase, BCT-100, in children with relapsed/refractory hematological, solid or CNS cancers. Procedure: PARC was a single arm, Phase I/II, international, open label study. BCT-100 was given intravenously over one hour at weekly intervals. The Phase I section utilized a modified 3 + 3 design where escalation/de-escalation was based on both the safety profile and the complete depletion of arginine (defined as adequate arginine depletion; AAD <8µM arginine in the blood after 4 doses of BCT-100). The Phase II section was designed to further evaluate the clinical activity of BCT-100 at the pediatric RP2D determined in the Phase I section, by recruitment of patients with pediatric cancers into 4 individual groups. A primary evaluation of response was conducted at eight weeks with patients continuing to receive treatment until disease progression or unacceptable toxicity. Results: 49 children were recruited globally. The Phase I cohort of the trial established the Recommended Phase II Dose of 1600U/kg iv weekly in children, matching that of adults. BCT-100 was very well tolerated. No responses defined as a CR, CRi or PR were seen in any cohort within the defined 8 week primary evaluation period. However a number of these relapsed/refractory patients experienced prolonged radiological SD. Conclusion: Arginine depletion is a clinically safe and achievable strategy in children with cancer. The RP2D of BCT-100 in children with relapsed/refractory cancers is established at 1600U/kg intravenously weekly and can lead to sustained disease stability in this hard to treat population. Clinical trial registration: EudraCT, 2017-002762-44; ISRCTN, 21727048; and ClinicalTrials.gov, NCT03455140.

2.
Pediatr Neurosurg ; 58(5): 290-298, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37604126

RESUMO

BACKGROUND: Paediatric low-grade gliomas (pLGGs) are the most common primary brain tumour in children. Though considered benign, slow-growing lesions with excellent overall survival, their long-term morbidity can be significant, both from the tumour and secondary to treatment. Vast progress has been made in recent years to better understand the molecular biology underlying pLGGs, with promising implications for new targeted therapeutic strategies. SUMMARY: A multi-layered classification system of biologic subgroups, integrating distinct molecular and histological features has evolved to further our clinical understanding of these heterogeneous tumours. Though surgery and chemotherapy are the mainstays of treatment for pLGGs, many tumours are not amenable to surgery and/or progress after conventional chemotherapy. Therapies targeting common genetic aberrations in the RAS-mitogen-activated protein kinase (RAS/MAPK) pathway have been the focus of many recent studies and offer new therapeutic possibilities. Here, we summarise the updated molecular classification of pLGGs and provide a review of current treatment strategies, novel agents, and open trials. KEY MESSAGES: (1) There is a need for treatment strategies in pLGG that provide lasting tumour control and better quality of survival through minimising toxicity and protecting against neurological, cognitive, and endocrine deficits. (2) The latest World Health Organisation classification of pLGG incorporates a growing wealth of molecular genetic information by grouping tumours into more biologically and molecularly defined entities that may enable better risk stratification of patients, and consideration for targeted therapies in the future. (3) Novel agents and molecular-targeted therapies offer new therapeutic possibilities in pLGG and have been the subject of many recent and currently open clinical studies. (4) Adequate molecular characterisation of pLGG is therefore imperative in today's clinical trials, and treatment responses should not only be evaluated radiologically but also using neurological, visual, and quality of life outcomes to truly understand treatment benefits.


Assuntos
Neoplasias Encefálicas , Glioma , Criança , Humanos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Qualidade de Vida , Glioma/genética , Glioma/terapia
3.
Neuro Oncol ; 25(4): 774-785, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36239316

RESUMO

BACKGROUND: Bevacizumab is increasingly used in children with pediatric low-grade glioma (PLGG) despite limited evidence. A nationwide UK service evaluation was conducted to provide larger cohort "real life" safety and efficacy data including functional visual outcomes. METHODS: Children receiving bevacizumab-based treatments (BBT) for PLGG (2009-2020) from 11 centers were included. Standardized neuro-radiological (RANO-LGG) and visual (logMAR visual acuity) criteria were used to assess clinical-radiological correlation, survival outcomes and multivariate prognostic analysis. RESULTS: Eighty-eight children with PLGG received BBT either as 3rd line with irinotecan (85%) or alongside 1st/2nd line chemotherapies (15%). Toxicity was limited and minimal. Partial response (PR, 40%), stable disease (SD, 49%), and progressive disease (PD, 11%) were seen during BBT. However, 65% progressed at 8 months (median) from BBT cessation, leading to a radiology-based 3 yr-progression-free survival (PFS) of 29%. Diencephalic syndrome (P = .03) was associated with adverse PFS. Pre-existing visual morbidity included unilateral (25%) or bilateral (11%) blindness. Improvement (29%) or stabilization (49%) of visual acuity was achieved, more often in patients' best eyes. Vision deteriorated during BBT in 14 (22%), with 3-year visual-PFS of 53%; more often in patients' worst eyes. A superior visual outcome (P = .023) was seen in neurofibromatosis type 1-associated optic pathway glioma (OPG). Concordance between visual and radiological responses was 36%; optimized to 48% using only best eye responses. CONCLUSIONS: BBTs provide effective short-term PLGG control and delay further progression, with a better sustained visual (best > worst eye) than radiological response. Further research could optimize the role of BBT toward a potentially sight-saving strategy in OPG.


Assuntos
Glioma do Nervo Óptico , Criança , Humanos , Bevacizumab/uso terapêutico , Glioma do Nervo Óptico/tratamento farmacológico , Irinotecano , Acuidade Visual , Reino Unido
4.
Int J Radiat Oncol Biol Phys ; 111(4): 968-978, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34217789

RESUMO

PURPOSE: There is limited evidence to define the role of radiation therapy in children with metastatic rhabdomyosarcoma (mRMS). In the international BERNIE study, children with mRMS or non-RMS soft tissue sarcoma were randomized to receive standard chemotherapy with or without bevacizumab, with radiation therapy to all disease sites recommended after chemotherapy cycle 6. We retrospectively evaluated the impact of radiation therapy on survival in the mRMS cohort. METHODS AND MATERIALS: Patients were grouped according to the radiation therapy they received: radical, partial, or none. Radical irradiation was defined as radiation therapy delivered to all disease sites, unless a site was completely surgically resected. Partial irradiation was defined as radiation therapy to ≥1, but not all, disease sites. Landmark analysis excluded patients with an event before day 221. Overall survival (OS) and event-free survival (EFS) were modeled using Cox proportional hazards models. RESULTS: Of 102 patients with mRMS, 97 were included in the analysis for OS and 85 for EFS. Overall, 27 patients received radical irradiation, 46 partial irradiation, and 24 no irradiation. EFS was not significantly different among patient groups after adjustment for prognostic factors (hazard ratio [HR] = 0.520; P = .054 for any vs no irradiation). Radiation therapy was associated with improved OS compared with no radiation therapy (adjusted HR = 0.249; P = .00025), with OS being greater for radical versus partial irradiation (HR = 0.245; P = .039). The 3-year OS rate was 84%, 54%, and 23% for patients receiving radical, partial, and no irradiation, respectively. Radical treatment (surgery, irradiation, or both) of the primary site improved EFS and OS compared with no treatment. CONCLUSIONS: These findings demonstrate variability in the application of radiation therapy for mRMS and support the routine use of radical treatment to the primary site. Radical irradiation to metastatic sites may further improve OS. The burden of such treatment should be balanced against prognosis; further studies are needed.


Assuntos
Rabdomiossarcoma , Sarcoma , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica , Criança , Humanos , Metástase Neoplásica , Segunda Neoplasia Primária , Estudos Retrospectivos , Rabdomiossarcoma/radioterapia , Sarcoma/tratamento farmacológico , Neoplasias de Tecidos Moles
5.
ACS Appl Mater Interfaces ; 13(30): 35266-35280, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34310112

RESUMO

The lack of clinical response to the alkylating agent temozolomide (TMZ) in pediatric diffuse midline/intrinsic pontine glioma (DIPG) has been associated with O6-methylguanine-DNA-methyltransferase (MGMT) expression and mismatch repair deficiency. Hence, a potent N(3)-propargyl analogue (N3P) was derived, which not only evades MGMT but also remains effective in mismatch repair deficient cells. Due to the poor pharmacokinetic profile of N3P (t1/2 < 1 h) and to bypass the blood-brain barrier, we proposed convection enhanced delivery (CED) as a method of administration to decrease dose and systemic toxicity. Moreover, to enhance N3P solubility, stability, and sustained distribution in vivo, either it was incorporated into an apoferritin (AFt) nanocage or its sulfobutyl ether ß-cyclodextrin complex was loaded into nanoliposomes (Lip). The resultant AFt-N3P and Lip-N3P nanoparticles (NPs) had hydrodynamic diameters of 14 vs 93 nm, icosahedral vs spherical morphology, negative surface charge (-17 vs -34 mV), and encapsulating ∼630 vs ∼21000 N3P molecules per NP, respectively. Both NPs showed a sustained release profile and instant uptake within 1 h incubation in vitro. In comparison to the naked drug, N3P NPs demonstrated stronger anticancer efficacy against 2D TMZ-resistant DIPG cell cultures [IC50 = 14.6 (Lip-N3P) vs 32.8 µM (N3P); DIPG-IV) and (IC50 = 101.8 (AFt-N3P) vs 111.9 µM (N3P); DIPG-VI)]. Likewise, both N3P-NPs significantly (P < 0.01) inhibited 3D spheroid growth compared to the native N3P in MGMT+ DIPG-VI (100 µM) and mismatch repair deficient DIPG-XIX (50 µM) cultures. Interestingly, the potency of TMZ was remarkably enhanced when encapsulated in AFt NPs against DIPG-IV, -VI, and -XIX spheroid cultures. Dynamic PET scans of CED-administered zirconium-89 (89Zr)-labeled AFt-NPs in rats also demonstrated substantial enhancement over free 89Zr radionuclide in terms of localized distribution kinetics and retention within the brain parenchyma. Overall, both NP formulations of N3P represent promising approaches for treatment of TMZ-resistant DIPG and merit the next phase of preclinical evaluation.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Portadores de Fármacos/química , Glioma/tratamento farmacológico , Nanopartículas/química , Temozolomida/análogos & derivados , Temozolomida/uso terapêutico , Animais , Apoferritinas/química , Linhagem Celular Tumoral , Humanos , Lipossomos/química , Masculino , Ratos Wistar , Esferoides Celulares/efeitos dos fármacos , beta-Ciclodextrinas/química
6.
BMJ Open ; 11(6): e051091, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34078638

RESUMO

INTRODUCTION: Survivors of childhood brain tumours have the poorest health-related quality of life of all cancer survivors due to the multiple physical and psychological sequelae of brain tumours and their treatment. Remotely delivered acceptance and commitment therapy (ACT) may be a suitable and accessible psychological intervention to support young people who have survived brain tumours. This study aims to assess the feasibility and acceptability of remotely delivered ACT to improve quality of life among these young survivors. METHODS AND ANALYSIS: This study is a two-arm, parallel group, randomised controlled trial comparing ACT with waitlist control at 12-week follow-up as the primary endpoint. Seventy-two participants will be recruited, who are aged 11-24 and have completed brain tumour treatment. Participants will be randomised to receive 12 weeks of ACT either immediately or after a 12-week wait. The DNA-v model of ACT will be employed, which is a developmentally appropriate model for young people. Feasibility will be assessed using the proportion of those showing interest who consent to the trial and complete the intervention. Acceptability will be assessed using participant evaluations of the intervention, alongside qualitative interviews and treatment diaries analysed thematically. A range of clinical outcome measures will also assess physical and mental health, everyday functioning, quality of life and service usage at 12-week follow-up. The durability of treatment effects will be assessed by further follow-up assessments at 24 weeks, 36 weeks and 48 weeks. ETHICS AND DISSEMINATION: Ethical approval was given by East Midlands, Nottingham 1 Research Ethics Committee (Reference: 20/EM/0237). Study results will be disseminated in peer-reviewed journals, through public events and relevant third sector organisations. TRIAL REGISTRATION: ISRCTN10903290; NCT04722237.


Assuntos
Terapia de Aceitação e Compromisso , Neoplasias Encefálicas , Adolescente , Neoplasias Encefálicas/terapia , Estudos de Viabilidade , Humanos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Sobreviventes
7.
Eur J Cancer ; 142: 112-122, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33249395

RESUMO

INTRODUCTION: Extracranial rhabdoid tumours are rare, highly aggressive malignancies primarily affecting young children. The EU-RHAB registry was initiated in 2009 to prospectively collect data of rhabdoid tumour patients treated according to the EU-RHAB therapeutic framework. METHODS: We evaluated 100 patients recruited within EU-RHAB (2009-2018). Tumours and matching blood samples were examined for SMARCB1 mutations by sequencing and cytogenetics. RESULTS: A total of 70 patients presented with extracranial, extrarenal tumours (eMRT) and 30 with renal rhabdoid tumours (RTK). Nine patients demonstrated synchronous tumours. Distant metastases at diagnosis (M+) were present in 35% (35/100), localised disease (M0) with (LN+) and without (LN-) loco-regional lymph node involvement in 65% (65/100). SMARCB1 germline mutations (GLM) were detected in 21% (17/81 evaluable) of patients. The 5-year overall survival (OS) and event-free survival (EFS) rates were 45.8 ± 5.4% and 35.2 ± 5.1%, respectively. On univariate analyses, age at diagnosis (≥12 months), M0-stage, absence of synchronous tumours, absence of a GLM, gross total resection (GTR), radiotherapy and achieving a CR were significantly associated with favourable outcomes. In an adjusted multivariate model presence of a GLM, M+ and lack of a GTR were the strongest significant negative predictors of outcome. CONCLUSIONS: We suggest to stratify patients with localised disease (M0), GTR+ and without proof of a GLM (5-year OS 72.2 ± 9.9%) as 'standard risk'. Patients presenting with one of the features M+ and/or GTR- and/or GLM+ belong to a high risk group (5-year, OS 32.5 ± 6.2%). These patients need novel therapeutic strategies such as combinations of targeted agents with conventional chemotherapy or novel experimental approaches ideally within international phase I/II trials.


Assuntos
Tumor Rabdoide/epidemiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Fatores de Risco
8.
Pediatr Pulmonol ; 55(8): 2074-2081, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32511892

RESUMO

Patients with pulmonary Langerhans cell histiocytosis (LCH) typically have a benign course but may have extensive cystic lung disease with rare life-threatening complications including multiple and recurrent pneumothoraces and respiratory failure. We report seven severely affected pediatric patients treated with chemotherapy, aggressive chest tube management, and pleurodesis of whom five survived. Patients with extraordinary amounts of pulmonary cystic disease and multiple pneumothoraces due to LCH can have remarkable, curative outcomes with early recognition, optimal LCH-directed therapy, and supportive care.


Assuntos
Histiocitose/terapia , Pneumopatias/terapia , Pneumotórax/terapia , Adolescente , Tubos Torácicos , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pleurodese
9.
Arch Dis Child ; 105(3): 241-246, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31420330

RESUMO

BACKGROUND: The National Institute for Health and Care Excellence (NICE) guidance for referral of children with suspected cancer was first published in 2005 and updated in 2015. The updated version relied on sparse primary care evidence and published without input from key stakeholders, for example, acute general paediatricians and paediatric haematologists/oncologists. This led to a document that fell short as a practical guide for referring physicians managing children with potentially life-threatening conditions. Following discussions between the Children's Cancer and Leukaemia Group (CCLG, the UK multidisciplinary professional body for healthcare professionals caring for children with cancer) and NICE, it was agreed that a practical supplement should be produced for the 2015 guidance. A prerequisite was evidence gathering from tertiary care to balance the existing primary care evidence, and a Delphi consensus method was therefore convened. METHODS: A CCLG NICE Guidance Committee formulated 25 draft statements for review. The CCLG emailed its paediatric haematologist/oncologist membership (n=179) and 88 responded (49%). To achieve consensus, statements required ≥70% agreement from ≥60% of actual respondents, from the denominator (n=88). RESULTS: Fifteen of 25 original statements were accepted at the first round of voting. Three of 25 statements where >50% did not support were rejected outright. One statement could not be revised without replicating a previously accepted statement. The six remaining statements were revised and a second round of voting undertaken; all six revised statements were accepted. Overall, 21 of 25 statements (84%) met consensus criteria. CONCLUSIONS: This expert opinion should help streamline suspected cancer referral in children and help optimise subsequent outcomes.


Assuntos
Prova Pericial , Neoplasias/diagnóstico , Guias de Prática Clínica como Assunto , Encaminhamento e Consulta , Criança , Consenso , Técnica Delphi , Detecção Precoce de Câncer , Humanos , Neoplasias/terapia , Fatores de Tempo , Reino Unido
10.
Arch Dis Child ; 104(1): 25-29, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29730641

RESUMO

OBJECTIVE: To determine the likely rate of patient randomisation and to facilitate sample size calculation for a full-scale phase III trial of varicella zoster immunoglobulin (VZIG) and aciclovir as postexposure prophylaxis against chickenpox in children with cancer. DESIGN: Multicentre pilot randomised controlled trial of VZIG and oral aciclovir. SETTING: England, UK. PATIENTS: Children under 16 years of age with a diagnosis of cancer: currently or within 6 months of receiving cancer treatment and with negative varicella zoster virus (VZV) serostatus at diagnosis or within the last 3 months. INTERVENTIONS: Study participants who have a significant VZV exposure were randomised to receive PEP in the form of VZIG or aciclovir after the exposure. MAIN OUTCOME MEASURES: Number of patients registered and randomised within 12 months of the trial opening to recruitment and incidence of breakthrough varicella. RESULTS: The study opened in six sites over a 13-month period. 482 patients were screened for eligibility, 32 patients were registered and 3 patients were randomised following VZV exposure. All three were randomised to receive aciclovir and there were no cases of breakthrough varicella. CONCLUSIONS: Given the limited recruitment to the PEPtalk2 pilot, it is unlikely that the necessary sample size would be achievable using this strategy in a full-scale trial. The study identified factors that could be used to modify the design of a definitive trial but other options for defining the best means to protect such children against VZV should be explored. TRIAL REGISTRATION NUMBER: ISRCTN48257441, EudraCT number: 2013-001332-22, sponsor: University of Birmingham.


Assuntos
Aciclovir/uso terapêutico , Soros Imunes , Neoplasias , Profilaxia Pós-Exposição/métodos , Adolescente , Antivirais/uso terapêutico , Criança , Pré-Escolar , Inglaterra , Feminino , Herpesvirus Humano 3/efeitos dos fármacos , Herpesvirus Humano 3/isolamento & purificação , Humanos , Imunização Passiva/métodos , Masculino , Neoplasias/complicações , Neoplasias/terapia , Projetos Piloto , Resultado do Tratamento
11.
Eur J Cancer ; 83: 177-184, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28738258

RESUMO

PURPOSE: We evaluated the role of bevacizumab as part of the multi-modality treatment of children and adolescents with metastatic rhabdomyosarcoma (RMS) or non-rhabdomyosarcoma soft tissue sarcoma (NRSTS). PATIENTS AND METHODS: Eligible patients aged ≥6 months to <18 years were randomised to receive induction chemotherapy (four cycles of IVADo + five cycles of IVA, ±bevacizumab), surgery and/or radiotherapy, followed by maintenance chemotherapy (12 cycles of low-dose cyclophosphamide + vinorelbine, ±bevacizumab). The primary objective was event-free survival (EFS) evaluated by an independent radiological review committee. RESULTS: One hundred and fifty-four patients were randomised to receive chemotherapy alone (n = 80) or with bevacizumab (n = 74). At the data cut-off for the primary efficacy analysis, median EFS was 14.9 months (95% confidence interval [CI]: 10.8-35.9) with chemotherapy and 20.6 months (95% CI: 15.2-24.9) with bevacizumab plus chemotherapy (stratified hazard ratio [HR] = 0.93; 95% CI: 0.61-1.41; P = 0.72). The HR for EFS in patients with RMS (n = 103) was 1.24 (95% CI: 0.73-2.09) versus 0.64 (95% CI: 0.32-1.26) for those with NRSTS (n = 49). Objective response rate was 36.0% (95% CI: 25.2-47.9) with chemotherapy and 54.0% (95% CI: 40.9-66.6) with bevacizumab plus chemotherapy (difference of 18.0%; 95% CI: 0.6-35.3). There were no treatment-related deaths and no increased incidence of grade 3/4 toxicities with bevacizumab. CONCLUSION: The addition of bevacizumab to chemotherapy appeared tolerable in children and adolescents with metastatic RMS/NRSTS, but the primary end-point of EFS did not show statistically significant improvement. TRIAL REGISTRATION: ClinicalTrials.gov, NCT00643565.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/uso terapêutico , Sarcoma/tratamento farmacológico , Neoplasias de Tecidos Moles/tratamento farmacológico , Adolescente , Inibidores da Angiogênese/efeitos adversos , Bevacizumab/efeitos adversos , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Humanos , Quimioterapia de Indução/métodos , Lactente , Quimioterapia de Manutenção/métodos , Masculino , Neoplasias de Tecidos Moles/patologia
12.
Front Oncol ; 7: 45, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28401060

RESUMO

Recent exciting work partly through The Cancer Genome Atlas has implicated epigenetic mechanisms including histone modifications in the development of both pediatric and adult high-grade glioma (HGG). Histone lysine methylation has emerged as an important player in regulating gene expression and chromatin function. Lysine (K) 27 (K27) is a critical residue in all seven histone 3 variants and the subject of posttranslational histone modifications, as it can be both methylated and acetylated. In pediatric HGG, two critical single-point mutations occur in the H3F3A gene encoding the regulatory histone variant H3.3. These mutations occur at lysine (K) 27 (K27M) and glycine (G) 34 (G34R/V), both of which are involved with key regulatory posttranscriptional modifications. Therefore, these mutations effect gene expression, cell differentiation, and telomere maintenance. In recent years, alterations in histone acetylation have provided novel opportunities to explore new pharmacological targeting, with histone deacetylase (HDAC) overexpression reported in high-grade, late-stage proliferative tumors. HDAC inhibitors have shown promising therapeutic potential in many malignancies. This review focuses on the epigenetic mechanisms propagating pediatric and adult HGGs, as well as summarizing the current advances in clinical trials using HDAC inhibitors.

14.
Ecancermedicalscience ; 10: 630, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27110286

RESUMO

The first Workshop on Drug Delivery in Paediatric Brain Tumours was hosted in London by the charity Children with Cancer UK. The goals of the workshop were to break down the barriers to treating central nervous system (CNS) tumours in children, leading to new collaborations and further innovations in this under-represented and emotive field. These barriers include the physical delivery challenges presented by the blood-brain barrier, the underpinning reasons for the intractability of CNS cancers, and the practical difficulties of delivering cancer treatment to the brains of children. Novel techniques for overcoming these problems were discussed, new models brought forth, and experiences compared.

15.
J Neuropathol Exp Neurol ; 74(9): 867-72, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26222501

RESUMO

Pilocytic astrocytomas (PAs) are increasingly tested for KIAA1549-BRAF fusions. We used reverse transcription polymerase chain reaction for the 3 most common KIAA1549-BRAF fusions, together with BRAF V600E and histone H3.3 K27M analyses to identify relationships of these molecular characteristics with clinical features in a cohort of 32 PA patients. In this group, the overall BRAF fusion detection rate was 24 (75%). Ten (42%) of the 24 had the 16-9 fusion, 8 (33%) had only the 15-9 fusion, and 1 (4%) of the patients had only the 16-11 fusion. In the PAs with only the 15-9 fusion, 1 PA was in the cerebellum and 7 were centered in the midline outside of the cerebellum, that is, in the hypothalamus (n = 4), optic pathways (n = 2), and brainstem (n = 1). Tumors within the cerebellum were negatively associated with fusion 15-9. Seven (22%) of the 32 patients had tumor-related deaths and 25 of the patients (78%) were alive between 2 and 14 years after initial biopsy. Age, sex, tumor location, 16-9 fusion, and 15-9 fusion were not associated with overall survival. Thus, in this small cohort, 15-9 KIAA1549-BRAF fusion was associated with midline PAs located outside of the cerebellum; these tumors, which are generally difficult to resect, are prone to recurrence.


Assuntos
Astrocitoma/diagnóstico , Astrocitoma/genética , Neoplasias Cerebelares/diagnóstico , Neoplasias Cerebelares/genética , Fusão Gênica/genética , Proteínas Proto-Oncogênicas B-raf/genética , Adolescente , Cerebelo/patologia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Humanos , Lactente , Masculino
16.
Front Oncol ; 5: 54, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25785246

RESUMO

The mitogen-activated protein kinase (MAPK) pathway is known to play a key role in the initiation and maintenance of many tumors as well as normal development. This often occurs through mutation of the genes encoding RAS and RAF proteins which are involved in signal transduction in this pathway. BRAF is one of three RAF kinases which act as downstream effectors of growth factor signaling leading to cell cycle progression, proliferation, and survival. Initially reported as a point mutation (V600E) in the majority of metastatic melanomas, other alterations in the BRAF gene have now been reported in a variety of human cancers including papillary thyroid cancer, colon carcinomas, hairy cell leukemia, and more recently in gliomas. The identification of oncogenic mutations in the BRAF gene have led to a revolution in the treatment of metastatic melanoma using targeted molecular therapies that affect the MAPK pathway either directly through BRAF inhibition or downstream through inhibition of MEK. This review describes the molecular biology of BRAF in the context of pediatric low-grade gliomas, the role of BRAF as a diagnostic marker, the prognostic implications of BRAF, and evidence for therapeutic targeting of BRAF.

17.
Front Oncol ; 4: 176, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25101241

RESUMO

As advances in the molecular and genetic profiling of pediatric medulloblastoma evolve, associations with prognosis and treatment are found (prognostic and predictive biomarkers) and research is directed at molecular therapies. Medulloblastoma typically affects young patients, where the implications of any treatment on the developing brain must be carefully considered. The aim of this article is to provide a clear comprehensible update on the role molecular profiling and subgroups in pediatric medulloblastoma as it is likely to contribute significantly toward prognostication. Knowledge of this classification is of particular interest because there are new molecular therapies targeting the Shh subgroup of medulloblastomas.

18.
Pediatr Blood Cancer ; 61(3): 464-72, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24039108

RESUMO

BACKGROUND: Improved survival of children with brain tumors (BTs) has increased focus on ameliorating morbidity. To reduce the risk of progressive cognitive decline, remedial strategies need to be instituted early, based upon accurate appraisal of need, yet few studies have investigated cognition in BT children early post-diagnosis. The study aims were to investigate cognition in children with primary BTs 1, 6, and 12 months post-diagnosis compared with healthy children, exploring the impact of disease and treatment variables. METHODS: Forty-eight children aged 2-16 years with primary BTs, referred to a Regional Neurosurgical Unit over the 2-year study period were eligible for enrollment. The "best friends" model was used to recruit matched controls. Cognition was assessed using age-appropriate Wechsler Intelligence scales; Children's Memory Scale; Test of Everyday Attention for Children, and Wechsler Quicktest. RESULTS: Patients with BTs had significantly reduced performance compared to controls early post-diagnosis in tests of Performance IQ, processing speed, verbal and visual memory, and selective attention. Improved performance over 12 months was seen in patients with BTs although also, for some measures, in controls. Significant deficits in cognitive performance were seen one year post-diagnosis for Verbal IQ; processing speed, visual and verbal immediate memory, and selective attention. Infratentorial site, high tumor grade, hydrocephalus, radiotherapy, and chemotherapy were associated with poorer functioning. CONCLUSION: Early cognitive impairment is present in BT children, sometimes prior to radiotherapy/chemotherapy treatment, and is associated with hydrocephalus, high tumor grade and infratentorial site. Future studies should investigate the role of early rehabilitation in improving cognition.


Assuntos
Neoplasias Encefálicas/psicologia , Cognição , Adolescente , Atenção , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/terapia , Quimiorradioterapia , Criança , Pré-Escolar , Feminino , Humanos , Inteligência , Masculino , Memória , Gradação de Tumores
19.
Ecancermedicalscience ; 7: 333, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23861728

RESUMO

The Third International Central Nervous System (CNS) Germ Cell Tumour (GCT) Symposium brought together over 100 delegates from all over the world to learn about the latest developments in these tumours and discuss future strategies for their management. Some areas of consensus were agreed upon, and controversies were discussed. Among these, the classification of GCTs and the surgical approach to their management were among the greatest areas of difference between different parts of the world. The need for radiotherapy (RT) as a part of standard first-line management for all malignant CNS GCTs was agreed, as well as the need for additional chemotherapy to maximise the cure in nongerminomatous malignant GCTs; the benefit of the addition of chemotherapy in localised germinoma to reduce the RT burden was also accepted as a good practice. The potential of biological parameters to assist the future diagnosis, treatment stratification, and disease monitoring for CNS GCTs was discussed. Such biological parameters may also represent targets for the development of novel therapies. The need for further collaboration between groups engaged in biological studies was agreed. The merits of proton beam RT were debated, and the importance of mitigating the long-term side effects of the treatment was underlined by a session on late effects.

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