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Featured researches published by Maaike J. Vos.


Neuro-oncology | 2007

The course of neurocognitive functioning in high-grade glioma patients

Ingeborg Bosma; Maaike J. Vos; Jan J. Heimans; Martin J. B. Taphoorn; Neil K. Aaronson; Tjeerd J. Postma; Henk M. van der Ploeg; Martin J. Muller; W. Peter Vandertop; Ben J. Slotman; Martin Klein

We evaluated the course of neurocognitive functioning in newly diagnosed high-grade glioma patients and specifically the effect of tumor recurrence. Following baseline assessment (after surgery and before radiotherapy), neurocognitive functioning was evaluated at 8 and 16 months. Neurocognitive summary measures were calculated to detect possible deficits in the domains of (1) information processing, (2) psychomotor function, (3) attention, (4) verbal memory, (5) working memory, and (6) executive functioning. Repeated-measures analyses of covariance were used to evaluate changes over time. Thirty-six patients were tested at baseline only. Follow-up data were obtained for 32 patients: 14 had a follow-up at 8 months, and 18 had an additional follow-up at 16 months. Between baseline and eight months, patients deteriorated in information-processing capacity, psychomotor speed, and attentional functioning. Further deterioration was observed between 8 and 16 months. Of 32 patients, 15 suffered from tumor recurrence before the eight-month follow-up. Compared with recurrence-free patients, not only did patients with recurrence have lower information-processing capacity, psychomotor speed, and executive functioning, but they also exhibited a more pronounced deterioration between baseline and eight-month follow-up. This difference could be attributed to the use of antiepileptic drugs in the patient group with recurrence. This study showed a marked decline in neurocognitive functioning in HGG patients in the course of their disease. Patients with tumor progression performed worse on neurocognitive tests than did patients without progression, which could be attributed to the use of antiepileptic drugs. The possibility of deleterious effects is important to consider when prescribing antiepileptic drug treatment.


Neuro-oncology | 2009

Health-related quality of life of long-term high-grade glioma survivors

Ingeborg Bosma; Jaap C. Reijneveld; Linda Douw; Maaike J. Vos; Tjeerd J. Postma; Neil K. Aaronson; Martin J. Muller; W. Peter Vandertop; Ben J. Slotman; Martin J. B. Taphoorn; Jan J. Heimans; Martin Klein

The objective of this study was to compare the health-related quality of life (HRQOL) of long-term to short-term high-grade glioma (HGG) survivors, determine the prognostic value of HRQOL for overall survival, and determine the effect of tumor recurrence on HRQOL for long-term survivors. Following baseline assessment (after surgery, before radiotherapy), self-perceived HRQOL (using the Medical Outcomes Study Short Form 36 [SF-36]) and brain tumor-specific symptoms (using the 20-item Brain Cancer Module) were assessed every 4 months until 16 months after histological diagnosis. Kaplan-Meier survival analysis and the Cox proportional hazards model were performed to estimate overall survival of patients with impaired scores on the aggregated SF-36 higher-order summary scores measuring physical functioning on a physical component scale and on a mental component scale (MCS). Sixteen patients with a short-term survival (baseline and 4-month follow-up) and 16 with a long-term survival (follow-up until 16 months after diagnosis) were selected out of 68 initially recruited HGG patients. At baseline, the short-term and long-term survivors did not differ in their HRQOL. Between baseline and the 4-month follow-up, HRQOL of short-term survivors deteriorated, whereas the long-term survivors improved to a level comparable to healthy controls. Patients with impaired mental functioning (MCS) at baseline had a shorter median survival than patients with normal functioning. After accounting for differences in patient and tumor characteristics, however, mental functioning was not independently related to poorer overall survival. Not surprisingly, in the group of long-term survivors, the five patients with recurrence had a more compromised HRQOL at the 16-month follow-up compared to the 11 patients without recurrence. We concluded that baseline HRQOL is not related to duration of survival and that long-term survivors show improvement of HRQOL to a level comparable to that of the healthy.


Journal of Clinical Oncology | 2003

Thallium-201 Single-Photon Emission Computed Tomography As an Early Predictor of Outcome in Recurrent Glioma

Maaike J. Vos; Otto S. Hoekstra; Frederik Barkhof; Johannes Berkhof; Jan J. Heimans; Cees J. van Groeningen; W. Peter Vandertop; Ben J. Slotman; Tjeerd J. Postma

PURPOSE With limited response rates and potential toxicity of chemotherapeutic treatment in patients with recurrent glioma, reliable response assessment is essential. Currently, the assessment of treatment response in glioma patients is based on the combination of radiologic and clinical findings. However, response monitoring with computed tomography (CT) or magnetic resonance imaging (MRI) is hampered by several pitfalls and is prone to interobserver variability. The aim of this study was to establish the value of thallium-201 single-photon emission computed tomography (201Tl-SPECT) as a predictor of overall survival and response to chemotherapy in recurrent glioma, and to compare the value of 201Tl-SPECT with that of CT and MRI. PATIENTS AND METHODS We studied patients who underwent CT or MRI and 201Tl-SPECT before chemotherapy (n = 57), and patients who also had undergone CT or MRI and 201Tl-SPECT after two courses of chemotherapy (n = 44). The value of the radiologic variables (CT-MRI tumor size, 201Tl-SPECT tumor size, and maximal tumor intensity) at baseline and at follow-up in predicting overall survival, and the percentage of patients alive and progression-free at 6 months (APF6) were examined using Cox regression and logistic regression analysis. RESULTS Both at baseline and at follow-up, 201Tl-SPECT maximal tumor intensity was the strongest predictive variable and was inversely related to overall survival and APF6. In particular, progression of maximal tumor intensity after two courses of chemotherapy was a powerful predictor of poor outcome. CONCLUSION 201Tl-SPECT is superior to conventional CT-MRI in the early prediction of overall survival and response to chemotherapy in patients with recurrent glioma.


Journal of Neurology, Neurosurgery, and Psychiatry | 2015

Seizure reduction in a low-grade glioma: more than a beneficial side effect of temozolomide

Johan A F Koekkoek; Linda Dirven; Jan J. Heimans; T.J. Postma; Maaike J. Vos; Jaap C. Reijneveld; M. J. B. Taphoorn

Background Seizures are a common symptom in patients with low-grade glioma (LGG), negatively influencing quality of life, if uncontrolled. Besides antiepileptic drugs, antitumour treatment might contribute to a reduction in seizure frequency. The aim of this study was to determine the effect of temozolomide (TMZ) chemotherapy on seizure frequency, to identify factors associated with post-treatment seizure reduction and to analyse the prognostic value of seizure reduction for survival. Methods We retrospectively reviewed adult patients with supratentorial LGG and epilepsy who received chemotherapy with TMZ as initial treatment or for progressive disease in two hospitals (VUmc Amsterdam; MCH The Hague) between 2002 and 2012. Results We identified 104 patients with LGG with epilepsy who had received TMZ. Uncontrolled epilepsy in the 3 months preceding chemotherapy was present in 66 of 104 (63.5%) patients. A ≥50% reduction in seizure frequency after 6 months occurred in 29 of 66 (43.9%) patients. Focal symptoms at presentation (OR 6.55; 95% CI 1.45 to 32.77; p=0.015) appeared to be positively associated with seizure reduction. Seizure reduction was an independent prognostic factor for progression-free survival (HR 0.32; 95% CI 0.15 to 0.66; p=0.002) and overall survival (HR 0.33; 95% CI 0.14 to 0.79; p=0.013), along with a histological diagnosis of oligodendroglioma (HR 0.38; 95% CI 0.17 to 0.86; p=0.021). Objective responses on MRI were similar for patients with and without seizure reduction. Conclusions TMZ may contribute to an important reduction in seizure frequency in patients with LGG. Seizure reduction following TMZ treatment has prognostic significance and may serve as an important clinical outcome measure in patients with LGG.


Nuclear Medicine Communications | 2007

Systematic review of the diagnostic accuracy of 201Tl single photon emission computed tomography in the detection of recurrent glioma.

Maaike J. Vos; Ban N. Tony; Otto S. Hoekstra; Tjeerd J. Postma; Jan J. Heimans; Lotty Hooft

ObjectiveTo determine the diagnostic accuracy of 201Tl SPECT in the detection of tumour recurrence in patients with previous radiotherapy for supratentorial glioma. MethodsThe databases of PubMed and Embase were searched for relevant studies. Two reviewers independently selected and extracted data on study characteristics, quality and accuracy of studies. Studies were included if they comprised at least six eligible patients who underwent 201Tl SPECT (index test) and in whom (histo)pathological confirmation (reference test) of the suspected brain lesion was obtained. Because of the methodological and statistical heterogeneity of the included studies, a quantitative meta-analysis was not performed. Instead, for every individual study, the sensitivity, specificity and diagnostic odds ratio of 201Tl SPECT was calculated. ResultsEight studies met the inclusion criteria. Only one was considered of high methodological quality. Methodological limitations referred most notably to blinding and patient selection. The diagnostic odds ratio was greater than 1 in all studies included, with a broad range (2–351), and relatively wide 95% confidence intervals. The sensitivity of 201Tl SPECT ranged from 0.43 to 1.00, and the specificity from 0.25 to 1.00. Conclusion201Tl SPECT seems a valuable method in the detection of tumour recurrence in patients treated with radiotherapy for supratentorial glioma. However, the evidence is not very robust because of the low quality and high heterogeneity of the studies included. Future studies are warranted to further explore the diagnostic potential of 201Tl SPECT, and to determine optimum thresholds for the detection of glioma recurrence.


European Journal of Cancer | 2015

The impact of bevacizumab on health-related quality of life in patients treated for recurrent glioblastoma: Results of the randomised controlled phase 2 BELOB trial

Linda Dirven; Martin J. van den Bent; Andrew Bottomley; Nelly van der Meer; Bronno van der Holt; Maaike J. Vos; Annemiek M.E. Walenkamp; Laurens V. Beerepoot; M. Hanse; Jaap C. Reijneveld; Aja Otten; Filip de Vos; Marion Smits; Jacoline E. C. Bromberg; Walter Taal; M. J. B. Taphoorn

BACKGROUND The BELOB study, a randomised controlled phase 2 trial comparing lomustine, bevacizumab and combined lomustine and bevacizumab in patients with recurrent glioblastoma, showed that the 9-month overall survival rate was most promising in the combination arm. Here we report the health-related quality of life (HRQoL) results, a secondary trial end-point. METHODS HRQoL was measured at baseline and every 6weeks until progression using the European Organisation for Research and Treatment of Cancer (EORTC) core questionnaire (QLQ-C30) and brain module (QLQ-BN20). HRQoL was assessed over time for five preselected scales (global health (GH), physical (PF) and social functioning (SF), motor dysfunction (MD) and communication deficit (CD)). Moreover, mean changes in HRQoL from baseline until progression were determined. RESULTS 138/148 patients with at least a baseline HRQoL assessment were analysed. Over time, HRQoL remained relatively stable in all treatment arms for all five scales, at least during the first three treatment cycles. More than half (54-61%) of the patients showed stable (<10 point change) or improved (⩾10 point change) HRQoL during their progression-free time, except for SF (43%), irrespective of treatment arm. Deterioration of mean HRQoL was most profound at disease progression for all scales except SF, which deteriorated earlier in disease course. Compared to baseline, 40% of patients had clinically relevant (⩾10 points) worse GH, PF and SF, while 44% and 31% had increased MD and CD at disease progression, irrespective of treatment arm. CONCLUSIONS Bevacizumab, whether or not in combination with lomustine, did not negatively affect HRQoL in patients treated for recurrent glioblastoma in this randomised study.


Neuro-oncology | 2017

Comparison of 2D (RANO) and volumetric methods for assessment of recurrent glioblastoma treated with bevacizumab-a report from the BELOB trial

Renske Gahrmann; Martin J. van den Bent; Bronno van der Holt; Rene Vernhout; Walter Taal; Maaike J. Vos; Jan Cees de Groot; Laurens V. Beerepoot; Jan Buter; Zwenneke Hendrieke Flach; Monique Hanse; Bas Jasperse; Marion Smits

Background The current method for assessing progressive disease (PD) in glioblastoma is according to the Response Assessment in Neuro-Oncology (RANO) criteria. Bevacizumab-treated patients may show pseudo-response on postcontrast T1-weighted (T1w) MRI, and a more infiltrative non-enhancing growth pattern on T2w/fluid attenuated inversion recovery (FLAIR) images. We investigated whether the RANO criteria remain the method of choice for assessing bevacizumab-treated recurrent glioblastoma when compared with various volumetric methods. Methods Patients with assessable MRI data from the BELOB trial (n = 148) were included. Patients were treated with bevacizumab, lomustine, or both. At first and second radiological follow-up (6 and 12 wk), PD was determined using the 2D RANO criteria and various volumetric methods based on enhancing tumor only and enhancing plus non-enhancing tumor. Differences in overall survival (OS) between PD and non-PD patients were assessed with the log-rank test and a Cox model. Hazard ratios (HRs) and their 95% CIs were determined. Results For all patients together, all methods (except subtraction of non-enhancing from enhancing volume at first follow-up) showed significant differences in OS between PD and non-PD patients (P < .001). The largest risk increase for death in case of PD at both first and second follow-up was found with the RANO criteria: HR = 2.81 (95% CI, 1.92-4.10) and HR = 2.80 (95% CI, 1.75-4.49), respectively. In the bevacizumab-treated patients, all methods assessed showed significant differences in OS between PD and non-PD patients. There were no significant differences between methods. Conclusions In the first 12 weeks, volumetric methods did not provide significant improvement over the RANO criteria as a posttreatment prognostic marker.


Neuroradiology | 2012

MRI and thallium-201 SPECT in the prediction of survival in glioma.

Maaike J. Vos; Johannes Berkhof; Otto S. Hoekstra; Ingeborg Bosma; Eefje M. Sizoo; Jan J. Heimans; Jaap C. Reijneveld; Esther Sanchez; Frank J. Lagerwaard; Jan Buter; David P. Noske; Tjeerd J. Postma

IntroductionThis paper aims to study the value of MRI and Thallium 201 (201Tl) single-photon emission computed tomography (SPECT) in the prediction of overall survival (OS) in glioma patients treated with temozolomide (TMZ) and to evaluate timing of radiological follow-up.MethodsWe included patients treated with TMZ chemoradiotherapy for newly diagnosed glioblastoma multiforme (GBM) and with TMZ for recurrent glioma. MRIs and 201Tl SPECTs were obtained at regular intervals. The value of both imaging modalities in predicting OS was examined using Cox regression analyses.ResultsAltogether, 138 MRIs and 113 201Tl SPECTs in 46 patients were performed. Both imaging modalities were strongly related to OS (P ≤ 0.02). In newly diagnosed GBM patients, the last follow-up MRI (i.e., after six adjuvant TMZ courses) and SPECT (i.e., after three adjuvant TMZ courses) were the strongest predictors of OS (P = 0.01). In recurrent glioma patients, baseline measurements appeared to be the most predictive of OS (P < 0.01). The addition of one imaging modality to the other did not contribute to the prediction of OS.ConclusionsBoth MRI and 201Tl SPECT are valuable in the prediction of OS. It is adequate to restrict to one of both modalities in the radiological follow-up during treatment. In the primary GBM setting, MRI after six adjuvant TMZ courses contributes significantly to the prediction of survival. In the recurrent glioma setting, baseline MRI appears to be a powerful predictor of survival, whereas follow-up MRIs during TMZ seem to be of little additional value.


European Journal of Neurology | 2016

Interobserver variability in the radiological assessment of magnetic resonance imaging (MRI) including perfusion MRI in glioblastoma multiforme.

Rogier E. Hagenbeek; Bf van der Kallen; Gj Lycklama à Nijeholt; Linda Dirven; M. J. B. Taphoorn; Maaike J. Vos

Conventional magnetic resonance imaging (MRI) has limited value for differentiation of true tumor progression and pseudoprogression in treated glioblastoma multiforme (GBM). Perfusion weighted imaging (PWI) may be helpful in the differentiation of these two phenomena. Here interobserver variability in routine radiological evaluation of GBM patients is assessed using MRI, including PWI.


CNS oncology | 2017

Visual inspection of MR relative cerebral blood volume maps has limited value for distinguishing progression from pseudoprogression in glioblastoma multiforme patients

Pauline L Tans; Rogier E. Hagenbeek; Geert J. Lycklama à Nijeholt; Finn K Holla; Tjeerd J. Postma; C.S.M. Straathof; Linda Dirven; Martin J. B. Taphoorn; Maaike J. Vos

AIM We examined whether visual interpretation of relative cerebral blood volume (rCBV) color maps made with dynamic susceptibility-weighted perfusion MRI can reliably distinguish progressive disease (PD) from pseudoprogression (PsPD) in glioblastoma patients during treatment with temozolomide chemoradiation. MATERIALS & METHODS Magnetic resonance (MR) perfusion-weighted images were evaluated based on visual inspection of rCBV maps. Sensitivity and specificity were calculated to assess if rCBV can reliably differentiate between PD and PsPD, during standard chemoradiation therapy. RESULTS Evaluation of dynamic susceptibility-weighted contrast-enhanced perfusion MRI by visual interpretation of rCBV maps did not differentiate PD from PsPD (sensitivity = 72%; specificity = 23%). Furthermore, the interpretation of the rCBV maps had no prognostic value regarding survival. CONCLUSION Qualitative rCBV-based dynamic susceptibility-weighted contrast-enhanced perfusion MRI does not reliably differentiate PD from PsPD, and is not prognostic for survival in glioblastoma multiforme patients during treatment with temozolomide chemoradiation.

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Jan J. Heimans

VU University Medical Center

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Linda Dirven

Leiden University Medical Center

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Tjeerd J. Postma

VU University Medical Center

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Jaap C. Reijneveld

VU University Medical Center

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Martin J. B. Taphoorn

Leiden University Medical Center

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Ben J. Slotman

VU University Medical Center

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M. J. B. Taphoorn

VU University Medical Center

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W. Peter Vandertop

VU University Medical Center

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Ingeborg Bosma

VU University Medical Center

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