Martin J van den Bent

University Hospital of Lausanne, Lausanne, Vaud, Switzerland

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Publications (237)1589.34 Total impact

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    ABSTRACT: Overall survival of patients with anaplastic oligodendroglial tumors has been improved due to the addition of procarbazine, lomustine and vincristine (PCV) chemotherapy to radiotherapy (RT), especially in 1p/19q-codeleted tumors. With improved survival, quality of survival becomes pivotal. We evaluated cognitive functioning and health-related quality of life (HRQOL) in a cohort of long-term anaplastic oligodendroglioma survivors. Thirty-two out of 37 long-term survivors included in European Organisation for Research and Treatment of Cancer (EORTC) study 26951 in the Netherlands and France participated. Cognition was assessed using neuropsychological tests for 6 domains, and HRQOL with the EORTC Quality of Life Questionnaire (EORTC QLQ-C30) and Brain Cancer Module (EORTC QLQ-BN20). Fatigue and mood were evaluated. Results were compared to healthy controls and to patients' own HRQOL 2.5 years following initial treatment. At the time of assessment, median survival for the patients was 147 months, 27 were still progression-free since initial treatment. Of progression-free patients, 26 % were not, and 30 % were severely cognitively impaired; 41 % were employed and 81 % could live independently. Patients' HRQOL was worse compared to controls, but similar to 2.5 years after initial treatment. Initial treatment (RT versus RT + PCV) was not correlated with cognition or HRQOL. In conclusion, cognitive functioning in long-term anaplastic oligodendroglioma survivors is variable. However, most patients function independently. In progression-free patients, HRQOL is relatively stable during the disease course. In this small sample, no effect of the addition of PCV on cognition or HRQOL was identified.
    Journal of Neuro-Oncology 10/2013; · 3.12 Impact Factor
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    ABSTRACT: Background In a previous study, the European Organisation for Research and Treatment of Cancer (EORTC) reported a scoring system to predict survival of patients with low-grade gliomas (LGGs). A major issue in the diagnosis of brain tumors is the lack of agreement among pathologists. New models in patients with LGGs diagnosed by central pathology review are needed.Methods Data from 339 EORTC patients with LGGs diagnosed by central pathology review were used to develop new prognostic models for progression-free survival (PFS) and overall survival (OS). Data from 450 patients with centrally diagnosed LGGs recruited into 2 large studies conducted by North American cooperative groups were used to validate the models.ResultsBoth PFS and OS were negatively influenced by the presence of baseline neurological deficits, a shorter time since first symptoms (<30 wk), an astrocytic tumor type, and tumors larger than 5 cm in diameter. Early irradiation improved PFS but not OS. Three risk groups have been identified (low, intermediate, and high) and validated.Conclusions We have developed new prognostic models in a more homogeneous LGG population diagnosed by central pathology review. This population better fits with modern practice, where patients are enrolled in clinical trials based on central or panel pathology review. We could validate the models in a large, external, and independent dataset. The models can divide LGG patients into 3 risk groups and provide reliable individual survival predictions. Inclusion of other clinical and molecular factors might still improve models' predictions.
    Neuro-Oncology 09/2013; · 6.18 Impact Factor
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    ABSTRACT: Background Recent molecular characterization studies have identified clinically relevant molecular subtypes to coexist within the same histological entities of glioma. Comparative studies between serum-supplemented and serum-free (SF) culture conditions have demonstrated that SF conditions select for glioma stem-like cells, which superiorly conserve genomic alterations. However, neither the representation of molecular subtypes within SF culture assays nor the molecular distinctions between successful and nonsuccessful attempts have been elucidated.MethodsA cohort of 261 glioma samples from varying histological grades was documented for SF culture success and clinical outcome. Gene expression and single nucleotide polymorphism arrays were interrogated on a panel of tumors for comparative analysis of SF+ (successful cultures) and SF- (unsuccessful cultures).ResultsSF culture outcome was correlated with tumor grade, while no relation was found between SF+ and patient overall survival. Copy number-based hierarchical clustering revealed an absolute separation between SF+ and SF- parental tumors. All SF+ cultures are derived from tumors that are isocitrate dehydrogenase 1 (IDH1) wild type, chromosome 7 amplified, and chromosome 10q deleted. SF- cultures derived from IDH1 mutant tumors demonstrated a fade-out of mutated cells during the first passages. SF+ tumors were enriched for The Cancer Genome Atlas Classical subtype and intrinsic glioma subtype-18. Comparative gene ontology analysis between SF+ and SF- tumors demonstrated enrichment for modules associated with extracellular matrix composition, Hox-gene signaling, and inflammation.ConclusionSF cultures are derived from a subset of parental tumors with a shared molecular background including enrichment for extracellular matrix-associated gene modules. These results provide leads to develop enhanced culture protocols for glioma samples not propagatable under current SF conditions.
    Neuro-Oncology 09/2013; · 6.18 Impact Factor
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    ABSTRACT: The long-term follow-up results from the EORTC-26951 trial showed that the addition of PCV after radiotherapy increases survival in anaplastic oligodendrogliomas/oligoastrocytomas (AOD/AOA). However, some patients appeared to benefit more from PCV treatment than others. We performed genome-wide methylation profiling of 115 samples included in the EORTC-26951 trial and extracted the CpG island hypermethylated phenotype (CIMP) and MGMT promoter-methylation (MGMT-STP27) status. We first demonstrate that methylation profiling can be performed on archival tissues with a performance that is similar to snap frozen tissue samples. We then performed methylation profiling on EORTC-26951 clinical trial samples. Univariate analysis indicated that CIMP+ or MGMT-STP27 methylated tumors had an improved survival compared to CIMP- and/or MGMT-STP27 unmethylated tumors (median overall survival (OS) 1.05 v. 6.46 years and 1.06 v. 3.8 years, both P<0.0001 for CIMP and MGMT-STP27 status respectively). Multivariable analysis indicates that CIMP and MGMT-STP27 are significant prognostic factors for survival in presence of age, sex performance score and review diagnosis in the model. CIMP+ and MGMT-STP27 methylated tumors showed a clear benefit from adjuvant PCV chemotherapy: the median OS of CIMP+ samples in the RT and RT-PCV arms was 3.27 and 9.51 years respectively P=0.0033; for MGMT-STP27 methylated samples it was 1.98 and 8.65 years. There was no such benefit for CIMP- or MGMT-STP27 unmethylated tumors. MGMT-STP27 status remained significant in an interaction test (P=0.003). Statistical analysis of microarrays (SAM) identified 259 novel CpGs associated with treatment response. MGMT-STP27 may be used to guide treatment decisions in this tumor type.
    Clinical Cancer Research 08/2013; · 7.84 Impact Factor
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    ABSTRACT: PURPOSEA randomized, phase III, placebo-controlled, partially blinded clinical trial (REGAL [Recentin in Glioblastoma Alone and With Lomustine]) was conducted to determine the efficacy of cediranib, an oral pan-vascular endothelial growth factor (VEGF) receptor tyrosine kinase inhibitor, either as monotherapy or in combination with lomustine versus lomustine in patients with recurrent glioblastoma. PATIENTS AND METHODS Patients (N = 325) with recurrent glioblastoma who previously received radiation and temozolomide were randomly assigned 2:2:1 to receive (1) cediranib (30 mg) monotherapy; (2) cediranib (20 mg) plus lomustine (110 mg/m(2)); (3) lomustine (110 mg/m(2)) plus a placebo. The primary end point was progression-free survival based on blinded, independent radiographic assessment of postcontrast T1-weighted and noncontrast T2-weighted magnetic resonance imaging (MRI) brain scans.ResultsThe primary end point of progression-free survival (PFS) was not significantly different for either cediranib alone (hazard ratio [HR] = 1.05; 95% CI, 0.74 to 1.50; two-sided P = .90) or cediranib in combination with lomustine (HR = 0.76; 95% CI, 0.53 to 1.08; two-sided P = .16) versus lomustine based on independent or local review of postcontrast T1-weighted MRI. CONCLUSION This study did not meet its primary end point of PFS prolongation with cediranib either as monotherapy or in combination with lomustine versus lomustine in patients with recurrent glioblastoma, although cediranib showed evidence of clinical activity on some secondary end points including time to deterioration in neurologic status and corticosteroid-sparing effects.
    Journal of Clinical Oncology 08/2013; · 18.04 Impact Factor
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    ABSTRACT: The prognosis of patients with anaplastic oligodendrogliomas (AOD) and oligoastrocytomas (AOA) is variable. Biomarkers might be helpful to identify more homogeneous disease subtypes and improve therapeutic index. The aim of this study is to develop new clinical, pathological and molecular prognostic models for locally diagnosed anaplastic gliomas with oligodendroglial features (AOD or AOA). Data from 368 patients with AOD or AOA recruited in The European Organisation for Research and Treatment of Cancer (EORTC) trial 26951 on adjuvant PCV (Procarbazine, CCNU, Vincristine) chemotherapy in anaplastic oligodendroglial tumours were used to develop multifactor models to predict progression free survival (PFS) and overall survival (OS). Different models were compared by their percentage of explained variation (PEV). Prognostic calculators were derived from these new models. Treatment (for PFS only), younger age, confirmed absence of residual tumour on imaging, frontal location, good World Health Organisation (WHO) performance status, absence of endothelial abnormalities and/or necrosis, 1p/19q codeletion and Isocitrate dehydrogenase 1 (IDH1) mutation were independent factors that predicted better PFS and OS. We identified important prognostic factors for AOD and AOA and showed that molecular markers added a major contribution to clinical and pathological factors in explaining PFS and OS. With a positive predictive value of 92% for PFS and 94% for OS, our models allow physicians to precisely identify high risk patients and aid in making therapeutic decisions.
    European journal of cancer (Oxford, England: 1990) 07/2013; · 4.12 Impact Factor
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    Acta Neuropathologica 06/2013; · 9.73 Impact Factor
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    ABSTRACT: Recent studies have indicated a prognostic role for genome-wide methylation in gliomas: Tumors that show an overall increase in DNA methylation at CpG sites (CIMP+; CpG island methylator phenotype) have a more favorable prognosis than CIMP- gliomas. Here, we have determined whether methylation profiling can identify more and clinically relevant molecular subtypes of glioma by performing genome-wide methylation profiling on 138 glial brain tumors of all histological diagnosis. Hopach (Hierarchical ordered partitioning and collapsing hybrid) clustering using the 1,000 most variable CpGs identified three distinct glioma subtypes (C+1p19q , C+wt , and C-) and one adult brain subtype. All "C+1p19q " and "C+wt " tumors were CIMP+ whereas most (50/54) "C-" tumors were CIMP-. The C- subtype gliomas contained many glioblastomas and all pilocytic astrocytomas. 1p19q LOH was frequent in the C+1p19q subtype. Other genetic changes (IDH1 mutation and EGFR amplification) and gene-expression based molecular subtypes also segregated in distinct methylation subtypes, demonstrating that these subtypes are also genetically distinct. Each subtype was associated with its own prognosis: median survival for C-, C+1p19q , and C+wt tumors was 1.18, 5.00, and 2.62 years, respectively. The prognostic value of these methylation subtypes was validated on an external dataset from the TCGA. Analysis of recurrences of 14 primary tumors samples indicates that shifts between some C+wt and C+1p/19q tumors can occur between the primary and recurrent tumor, but CIMP status remained stable. Our data demonstrate that methylation profiling identifies at least three prognostically relevant subtypes of glioma that can aid diagnosis and potentially guide treatment for patients. © 2013 Wiley Periodicals, Inc.
    Genes Chromosomes and Cancer 04/2013; · 3.55 Impact Factor
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    ABSTRACT: Background: Peripheral neuropathy is a frequent side effect of bortezomib chemotherapy. Relatively little is known about the clinical characteristics of this neuropathy, especially with respect to pain. Our aim was to describe the clinical characteristics and course of bortezomib-induced polyneuropathy. Methods: This is a retrospective cohort study of 39 patients diagnosed with bortezomib-induced polyneuropathy. Results: Pain is the most prominent symptom and 14 of 39 patients suffered from severe pain. More than 50% of our patients used analgesics due to moderate or severe pain. We found no correlation between severity of symptoms of bortezomib-induced polyneuropathy and cumulative dose or dose intensity of bortezomib. Nerve conduction studies did not correlate well with symptom severity. Dose reduction or discontinuation of treatment reduced severity in most cases. Conclusion: Painful polyneuropathy is a frequent, dose-limiting side effect of bortezomib with a relatively good prognosis. Careful neurological monitoring of symptoms and timely dose adjustment is important.
    The Netherlands Journal of Medicine 04/2013; 71(3):128-133. · 2.38 Impact Factor
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    ABSTRACT: Isocitrate dehydrogenase (IDH) mutational testing is becoming increasingly important. For this, robust and reliable assays are needed. We tested the variation of results between six laboratories of testing for IDH mutations. Each laboratory received five unstained slides from 31 formalin-fixed paraffin-embedded (FFPE) glioma samples, and followed its own standard IDH diagnostic routine. All laboratories used immunohistochemistry (IHC) with an antibody against the most frequent IDH1 mutation (R132H) as a first step. Three laboratories then sequenced only IHC negative cases while the others sequenced all cases. Based on the overall analysis, 13 samples from 11 tumors had an R132H mutation and one tumor showed an R132G mutation. Results of IHC for IDH1 R132H mutations in all six laboratories were completely in agreement, and identified all R132H mutations. Upon sequencing the results of two laboratories deviated from those of the others. After a review of the entire diagnostic process, on repeat (blinded) testing one laboratory was completely in agreement with the overall result. A change in technique did only partially improve the results in the other laboratory. IHC for the IDH1 R132H mutation is very reliable and consistent across laboratories. IDH sequencing procedures yielded inconsistent results in 2 out of 6 laboratories. Quality assurance is pivotal before IDH testing is made part of clinical management of patients.
    Journal of Neuro-Oncology 01/2013; · 3.12 Impact Factor
  • Martin J van den Bent, Kurt Jaeckle, Brigitta Baumert, Wolfgang Wick
    Journal of Clinical Oncology 01/2013; · 18.04 Impact Factor
  • M J van den Bent
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    ABSTRACT: Although the central role of 1p/19q codeletion in oligodendroglioma was established almost two decades ago, apart from clear prognostic significance the implications for clinical care have been less clear. This has changed with the long-term follow-up analysis of the EORTC and RTOG trials on procarbazine, lomustine, and vincristine (PCV) chemotherapy in anaplastic oligodendroglioma. These have shown that 1p/19q loss in these tumors is predictive of overall survival benefit of the addition of PCV chemotherapy to radiotherapy.
    American Society of Clinical Oncology educational book / ASCO. American Society of Clinical Oncology. Meeting. 01/2013; 2013:114-116.
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    ABSTRACT: PURPOSEIntrinsic glioma subtypes (IGSs) are molecularly similar tumors that can be identified based on unsupervised gene expression analysis. Here, we have evaluated the clinical relevance of these subtypes within European Organisation for Research and Treatment of Cancer (EORTC) 26951, a randomized phase III clinical trial investigating adjuvant procarbazine, lomustine, and vincristine (PCV) chemotherapy in anaplastic oligodendroglial tumors. Our study includes gene expression profiles of formalin-fixed, paraffin-embedded (FFPE) clinical trial samples. PATIENTS AND METHODS Gene expression profiling was performed in 140 samples, 47 fresh frozen samples and 93 FFPE samples, on HU133_Plus_2.0 and HuEx_1.0_st arrays, respectively.ResultsAll previously identified six IGSs are present in EORTC 26951. This confirms that different molecular subtypes are present within a well-defined histologic subtype. Intrinsic subtypes are highly prognostic for overall survival (OS) and progression-free survival (PFS). They are prognostic for PFS independent of clinical (age, performance status, and tumor location), molecular (1p/19q loss of heterozygosity [LOH], IDH1 mutation, and MGMT methylation), and histologic parameters. Combining known molecular (1p/19q LOH, IDH1) prognostic parameters with intrinsic subtypes improves outcome prediction (proportion of explained variation, 30% v 23% for each individual group of factors). Specific genetic changes (IDH1, 1p/19q LOH, and EGFR amplification) segregate into different subtypes. We identified one subtype, IGS-9 (characterized by a high percentage of 1p/19q LOH and IDH1 mutations), that especially benefits from PCV chemotherapy. Median OS in this subtype was 5.5 years after radiotherapy (RT) alone versus 12.8 years after RT/PCV (P = .0349; hazard ratio, 2.18; 95% CI, 1.06 to 4.50). CONCLUSION Intrinsic subtypes are highly prognostic in EORTC 26951 and improve outcome prediction when combined with other prognostic factors. Tumors assigned to IGS-9 benefit from adjuvant PCV.
    Journal of Clinical Oncology 12/2012; · 18.04 Impact Factor
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    Dataset: fon.10.134
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    ABSTRACT: Background. Autologous stem cell transplantation has greatly improved prognosis in systemic recurrent non-Hodgkin lymphoma. However, for systemic lymphoma relapsing in the central nervous system no prospective data are available concerning feasibility and efficacy. Therefore we performed an international multicenter retrospective study of patients with a central nervous system recurrence of systemic lymphoma to assess the outcome of these patients in the era of stem cell transplantation. Design and Methods. We collected clinical and treatment data on patients with a first central nervous system recurrence of systemic lymphoma treated between 2000 and 2010 in one of five centres in four countries. Patient- and treatment-related factors were analyzed and compared descriptively. Primary outcome measures were overall survival and percentage of patients transplanted. Results. We identified 92 patients, with a median age of 59 years and a median Eastern Cooperative Oncology Group/World health Organization performance status of 2, of whom 76% had diffuse large B-cell histology. The majority (79%) was treated with systemic chemotherapy with or without intravenous rituximab. Twenty-seven patients (29%) were transplanted; age and insufficient response to induction chemotherapy were the main reasons for not being transplanted in the remaining 65 patients. Median overall survival was 7 months (95% confidence interval 2.6-11.4); 8 months (95% confidence interval 3.8-5.2) for patients ≤ 65 years. One year survival was 34.8%; of the 27 transplanted patients 62% survived more than 1 year. The Memorial Sloan Kettering Prognostic Index for primary central nervous system lymphoma was prognostic for both achieving transplantation and survival. Conclusions. Despite the availability of autologous stem cell transplantation for patients with central nervous system progression or relapse of systemic lymphoma, prognosis is still poor. Long-term survival is, however, possible and more likely in patients able to undergo stem cell transplantation.
    Haematologica 11/2012; · 5.94 Impact Factor
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    ABSTRACT: The treatment of patients with recurrent glioblastoma remains a major oncologic problem, with median survival after progression of 7-9 months. To determine the maximum tolerated dose and dose-limiting toxicity (DLT), the combination of dasatinib and cyclonexyl-chloroethyl-nitrosourea (CCNU) was investigated in this setting. The study was designed as multicenter, randomized phase II trial, preceded by a lead-in safety phase. The safety component reported here, which also investigated pharmacokinetics and preliminary clinical activity, required expansion and is therefore considered a phase I part to establish a recommended dosing regimen of the combination of CCNU (90-110 mg/m(2)) and dasatinib (100-200 mg daily). Overall, 28 patients were screened, and 26 patients were enrolled. Five dose levels were explored. DLTs, mainly myelosuppression, occurred in 10 patients. Grade 3 or 4 neutropenia was recorded in 7 patients (26.9%) and thrombocytopenia in 11 patients (42.3%). No significant effect of CCNU coadministration on dasatinib pharmacokinetics was found. Median progression-free survival (PFS) was 1.35 months (95% confidence interval: 1.2-1.4) and 6-month PFS was 7.7%. In this phase I study of recurrent glioblastoma patients, the combination of CCNU and dasatinib showed significant hematological toxicities and led to suboptimal exposure to both agents.
    Neuro-Oncology 10/2012; · 6.18 Impact Factor
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    ABSTRACT: PURPOSEAnaplastic oligodendroglioma are chemotherapy-sensitive tumors. We now present the long-term follow-up findings of a randomized phase III study on the addition of six cycles of procarbazine, lomustine, and vincristine (PCV) chemotherapy to radiotherapy (RT). PATIENTS AND METHODS Adult patients with newly diagnosed anaplastic oligodendroglial tumors were randomly assigned to either 59.4 Gy of RT or the same RT followed by six cycles of adjuvant PCV. An exploratory analysis of the correlation between 1p/19q status and survival was part of the study. Retrospectively, the methylation status of the methyl-guanine methyl transferase gene promoter and the mutational status of the isocitrate dehydrogenase (IDH) gene were determined. The primary end points were overall survival (OS) and progression-free survival based on intent-to-treat analysis.ResultsA total of 368 patients were enrolled. With a median follow-up of 140 months, OS in the RT/PCV arm was significantly longer (42.3 v 30.6 months in the RT arm, hazard ratio [HR], 0.75; 95% CI, 0.60 to 0.95). In the 80 patients with a 1p/19q codeletion, OS was increased, with a trend toward more benefit from adjuvant PCV (OS not reached in the RT/PCV group v 112 months in the RT group; HR, 0.56; 95% CI, 0.31 to 1.03). IDH mutational status was also of prognostic significance. CONCLUSION The addition of six cycles of PCV after 59.4 Gy of RT increases both OS and PFS in anaplastic oligodendroglial tumors. 1p/19q-codeleted tumors derive more benefit from adjuvant PCV compared with non-1p/19q-deleted tumors.
    Journal of Clinical Oncology 10/2012; · 18.04 Impact Factor
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    Martin J van den Bent, Tom J Snijders, Jacoline E C Bromberg
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    ABSTRACT: Low grade gliomas affect predominantly young adults, and have a relatively favorable prognosis compared to grade III and grade IV gliomas. The challenge for an optimal management of these patients is to find the balance between an optimal survival and the preservation of neurological function including cognition. Because all medical treatments may induce side effects, in young and nearly asymptomatic patients the choices can be difficult. This review summarizes the current strategies: a watch-and-wait policy, surgery, chemotherapy, and radiotherapy.
    memo - Magazine of European Medical Oncology 09/2012; 5(3):223-227.
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    ABSTRACT: The methylation status of the O(6)-methylguanine-DNA methyltransferase (MGMT) gene is an important predictive biomarker for benefit from alkylating agent therapy in glioblastoma. Recent studies in anaplastic glioma suggest a prognostic value for MGMT methylation. Investigation of pathogenetic and epigenetic features of this intriguingly distinct behavior requires accurate MGMT classification to assess high throughput molecular databases. Promoter methylation-mediated gene silencing is strongly dependent on the location of the methylated CpGs, complicating classification. Using the HumanMethylation450 (HM-450K) BeadChip interrogating 176 CpGs annotated for the MGMT gene, with 14 located in the promoter, two distinct regions in the CpG island of the promoter were identified with high importance for gene silencing and outcome prediction. A logistic regression model (MGMT-STP27) comprising probes cg1243587 and cg12981137 provided good classification properties and prognostic value (kappa = 0.85; log-rank p < 0.001) using a training-set of 63 glioblastomas from homogenously treated patients, for whom MGMT methylation was previously shown to be predictive for outcome based on classification by methylation-specific PCR. MGMT-STP27 was successfully validated in an independent cohort of chemo-radiotherapy-treated glioblastoma patients (n = 50; kappa = 0.88; outcome, log-rank p < 0.001). Lower prevalence of MGMT methylation among CpG island methylator phenotype (CIMP) positive tumors was found in glioblastomas from The Cancer Genome Atlas than in low grade and anaplastic glioma cohorts, while in CIMP-negative gliomas MGMT was classified as methylated in approximately 50 % regardless of tumor grade. The proposed MGMT-STP27 prediction model allows mining of datasets derived on the HM-450K or HM-27K BeadChip to explore effects of distinct epigenetic context of MGMT methylation suspected to modulate treatment resistance in different tumor types.
    Acta Neuropathologica 07/2012; 124(4):547-60. · 9.73 Impact Factor

Publication Stats

11k Citations
1,589.34 Total Impact Points


  • 2005–2013
    • University Hospital of Lausanne
      • Service de radio-oncologie
      Lausanne, Vaud, Switzerland
  • 1996–2013
    • Netherlands Cancer Institute
      • • Department of Neuro-oncology
      • • Department of Medical Oncology
      Amsterdamo, North Holland, Netherlands
  • 1994–2013
    • Erasmus MC
      • • Department of Neurology
      • • Department of Internal Oncology
      Rotterdam, South Holland, Netherlands
  • 2012
    • University of Toronto
      • Department of Radiation Oncology
      Toronto, Ontario, Canada
    • HagaZiekenhuis van Den Haag
      's-Gravenhage, South Holland, Netherlands
    • Universiteit Utrecht
      • Division of Cell Biology
      Utrecht, Provincie Utrecht, Netherlands
    • Medical University of Vienna
      • Universitätsklinik für Innere Medizin I
      Vienna, Vienna, Austria
  • 1998–2012
    • Erasmus Universiteit Rotterdam
      • • Department of Neurology
      • • Daniel den Hoed Cancer Center
      Rotterdam, South Holland, Netherlands
  • 2011
    • Pierre and Marie Curie University - Paris 6
      • Centre de Recherche de l'Institut du Cerveau et de la Moelle Epinière
      Lutetia Parisorum, Île-de-France, France
  • 2009–2011
    • Ospedale Maggiore Carlo Alberto Pizzardi di Bologna
      • Department of Medical Oncology
      Bolonia, Emilia-Romagna, Italy
    • University of Zurich
      • Division of Neuropsychology
      Zürich, ZH, Switzerland
    • University of Virginia
      • Department of Neurology
      Charlottesville, VA, United States
  • 2010
    • Institut de Cancérologie Gustave Roussy
      Île-de-France, France
    • VU University Medical Center
      Amsterdamo, North Holland, Netherlands
    • Partners HealthCare
      Boston, Massachusetts, United States
    • National Center for Tumor Diseases (NCT) Heidelberg
      Heidelburg, Baden-Württemberg, Germany
  • 2008
    • Unité Inserm U1077
      Caen, Lower Normandy, France
  • 2004–2008
    • European Organisation for Research and Treatment of Cancer
      Bruxelles, Brussels Capital Region, Belgium
  • 2002–2008
    • Medisch Centrum Haaglanden
      's-Gravenhage, South Holland, Netherlands
  • 2007
    • Catharina Hospital
      Eindhoven, North Brabant, Netherlands
    • University Medical Center Utrecht
      • Department of Neurology
      Utrecht, Provincie Utrecht, Netherlands