Publications by authors named "Tom Snijders"

Background: Glioblastoma (GBM), the most common malignant brain tumor, is associated with devastating outcomes. IPAX-1 was a multicenter, open-label, single-arm phase I study to evaluate carrier-added 4--[I]iodo-phenylalanine ([I]IPA) plus external radiation therapy (XRT) in recurrent GBM.

Methods: A total of 10 adults with recurrent GBM who had received first-line debulking surgery plus radio-chemotherapy, were randomized to a single-dose regimen (1f; I-IPA 2 GBq before XRT); a fractionated parallel dose regimen (3f-p; 3 I-IPA 670 MBq fractions, in parallel with second-line XRT), or a fractionated sequential dose regimen (3f-s; 3 I-IPA 670 MBq fractions before and after XRT).

View Article and Find Full Text PDF

Purpose: Meningiomas classified as grade 2-3 according to the World Health Organisation (WHO) require combined surgery and in most cases radiotherapy (RT). Their initial management was evaluated using the Dutch Brain Tumour Registry.

Methods: The study included 393 patients aged ≥ 18 years with newly diagnosed meningioma WHO grade 2-3 between 2016 and 2021.

View Article and Find Full Text PDF

Background And Purpose: Treatment-induced effects are difficult to differentiate from progressive disease in radiologically progressing diffuse gliomas after treatment. This retrospective, single-center cohort study investigated the diagnostic value of arterial spin-labeling perfusion in differentiating progressive disease from treatment-induced effects in irradiated patients with a high-grade glioma.

Materials And Methods: Adults with a high-grade glioma diagnosed between January 1, 2012, and December 31, 2018, with a new or increasing contrast-enhancing lesion after radiotherapy with or without chemotherapy and arterial spin-labeling were consecutively included.

View Article and Find Full Text PDF

Background: Central nervous system hemangioblastomas are the most prevalent manifestation of von Hippel-Lindau (VHL) disease and remain the main cause of mortality. Surgical resection is the primary treatment strategy, but is not always possible, and should be used as restrictively as possible. There is an unmet need for less invasive treatment strategies, such as targeted therapy.

View Article and Find Full Text PDF

The performance of minimally invasive molecular diagnostic tools in brain tumors, such as liquid biopsy, has so far been limited by the blood-brain barrier (BBB). The BBB hinders the release of brain tumor biomarkers into the bloodstream. The use of focused ultrasound in conjunction with microbubbles has been shown to temporarily open the BBB (FUS-BBBO).

View Article and Find Full Text PDF

Background: Radiological progression may originate from progressive disease (PD) or pseudoprogression/treatment-associated changes. We assessed radiological progression in O6-methylguanine-DNA methyltransferase (MGMT) promoter-methylated glioblastoma treated with standard-of-care chemoradiotherapy with or without the integrin inhibitor cilengitide according to the modified response assessment in neuro-oncology (RANO) criteria of 2017.

Methods: Patients with ≥ 3 follow-up MRIs were included.

View Article and Find Full Text PDF

Upregulation of prostate-specific membrane antigen (PSMA) in neovasculature has been described in glioblastoma multiforme (GBM), whereas vasculature in nonaffected brain shows hardly any expression of PSMA. It is unclear whether PSMA-targeting tracer uptake on PET is based on PSMA-specific binding to neovasculature or aspecific uptake in tumor. Here, we quantified uptake of various PSMA-targeting tracers in GBM and correlated this with PSMA expression in tumor biopsy samples from the same patients.

View Article and Find Full Text PDF

Stochastic actor-oriented models (SAOMs) are a modelling framework for analysing network dynamics using network panel data. This paper extends the SAOM to the analysis of multilevel network panels through a random coefficient model, estimated with a Bayesian approach. The proposed model allows testing theories about network dynamics, social influence, and interdependence of multiple networks.

View Article and Find Full Text PDF

Background: Despite current best treatment options, a glioblastoma almost inevitably recurs after primary treatment. However, in the absence of clear evidence, current guidelines on recurrent glioblastoma are not well-defined. Re-resection is one of the possible treatment modalities, though it can be challenging to identify those patients who will benefit.

View Article and Find Full Text PDF
Article Synopsis
  • Meningiomas are the most common primary brain tumors, and this study aimed to analyze their incidence, prevalence, and prognosis in the Netherlands from 2000 to 2019.
  • Researchers used data from the Dutch Brain Tumour Registry and found that the incidence of meningioma diagnoses significantly increased over time, particularly for radiological cases.
  • The study reported a prevalence of 1012 per 1,000,000 people as of January 2020, with high 10-year survival rates for grade 1 tumors (91.0%) but lower rates for higher-grade tumors.
View Article and Find Full Text PDF

Background: Postoperative ischemia can lead to neurological deficits and is a known complication of glioma resection. There is inconsistency in documented incidence of ischemia after glioma resection, and the precise cause of ischemia is often unknown.

Objective: To assess the incidence of postoperative ischemia and neurological deficits after glioma resection and to evaluate their association with potential risk factors.

View Article and Find Full Text PDF

Background: While patients with diffuse low-grade glioma (LGG) often survive for years, there is a risk of tumor progression which may impact patients' long-term health-related quality of life (HRQOL) and neurocognitive functioning (NCF). We present a follow-up of LGG patients and their informal caregivers (T3) who took part in our previous HRQOL investigations (T1, M = 7 and T2 M = 13 years after diagnosis).

Methods: Participants completed HRQOL (short form-36 health survey [SF-36]; EORTC-BN20), fatigue (Checklist Individual Strength [CIS]), and depression (Center for Epidemiological Studies-Depression [CES-D]) questionnaires and underwent NCF assessments.

View Article and Find Full Text PDF

Background: Cognitive deficits occur in all different grades of glioma. In a recent study, we found these deficits to be independently, and possibly causally, related to survival in diffuse gliomas. In this study, we investigated whether the relationship between cognition and survival was mediated by three different factors: undertreatment, complications of treatment, and compliance.

View Article and Find Full Text PDF

Background: Primary vitreoretinal lymphoma (PVRL) is either unilateral or bilateral at initial presentation. Progression to a central nervous system (CNS) lymphoma is regularly observed and these patients seem to have an inferior survival. Knowledge of the predictive value of laterality for CNS progression may facilitate risk stratification and the development of more effective treatment strategies, and eventually, improve outcomes.

View Article and Find Full Text PDF
Article Synopsis
  • The study investigates how to differentiate between true progressive disease and treatment-induced effects in patients with high-grade gliomas using conventional MRI characteristics, highlighting the importance of accurate diagnosis.
  • Data from 210 patients revealed specific MRI features and time to progression that are associated with higher odds of diagnosing progressive disease, such as radiation dose, marginal enhancement, and isointense ADC signals.
  • The findings contribute to improving diagnostic models for assessing patient conditions post-treatment, underscoring the effectiveness of certain MRI characteristics in distinguishing between disease progression and treatment effects.
View Article and Find Full Text PDF

Background: Until 2015, Dutch guidelines recommended follow-up and biopsy rather than surgery as initial care for suspected low-grade gliomas (LGG). Given evidence that surgery could extend patient survival, our center stopped following this guideline on January 1, 2010 and opted for early maximal safe resection of LGG. The effects of early surgery on the ability of patients to work remains little documented.

View Article and Find Full Text PDF

Background: Validation of the 2016 RANO MRI scorecard for leptomeningeal metastasis failed for multiple reasons. Accordingly, this joint EORTC Brain Tumor Group and RANO effort sought to prospectively validate a revised MRI scorecard for response assessment in leptomeningeal metastasis.

Methods: Coded paired cerebrospinal MRI of 20 patients with leptomeningeal metastases from solid cancers at baseline and follow-up after treatment and instructions for assessment were provided via the EORTC imaging platform.

View Article and Find Full Text PDF
Article Synopsis
  • The study examined how certain molecular characteristics of diffuse gliomas affect neurocognitive functioning (NCF) in patients, suggesting that cognitive impairment is linked to specific tumor markers.
  • Researchers conducted a two-step analysis, first identifying 19 molecular markers of interest related to cognitive performance, and then correlating these markers with cognitive functions like memory and executive function in a cohort of glioma patients.
  • Findings revealed significant associations between several molecular markers (e.g., IDH-1, CD3) and cognitive abilities, indicating that glioma biology plays a role in influencing cognitive health independent of tumor size and location.
View Article and Find Full Text PDF

Purpose: Although standard-of-care has been defined for the treatment of glioblastoma patients, substantial practice variation exists in the day-to-day clinical management. This study aims to compare the use of laboratory tests in the perioperative care of glioblastoma patients between two tertiary academic centers-Brigham and Women's Hospital (BWH), Boston, USA, and University Medical Center Utrecht (UMCU), Utrecht, the Netherlands.

Methods: All glioblastoma patients treated according to standard-of-care between 2005 and 2013 were included.

View Article and Find Full Text PDF

Background: Despite the steady growth of sexual transmission of HIV, there is little evidence about safe sexual behavior of FSWs, and social network effects on this behavior, in Iran. Our aim in this study was to determine the effect of social network characteristics on condom use among FSWs, considering individual characteristics of the FSWs and of their sexual partners, characteristics of their relationship, and the FSW's personal network.

Methods: A cross-sectional ego-centric network survey of 170 FSWs was carried out in Tehran between January and June 2017.

View Article and Find Full Text PDF

Diffuse gliomas, which are at WHO grade II-IV, are progressive primary brain tumors with great variability in prognosis. Our aim was to investigate whether pre-operative cognitive functioning is of added value in survival prediction in these patients. In a retrospective cohort study of patients undergoing awake craniotomy between 2010 and 2019 we performed pre-operative neuropsychological assessments in five cognitive domains.

View Article and Find Full Text PDF

Objective: High frequency oscillations (HFOs) in intraoperative electrocorticography (ioECoG) are thought to be generated by hyperexcitable neurons. Inflammation may promote neuronal hyperexcitability. We investigated the relation between HFOs and inflammation in tumor-related epilepsy.

View Article and Find Full Text PDF

The onco-metabolite 2-hydroxyglutarate (2HG), a biomarker of IDH-mutant gliomas, can be detected with H MR spectroscopy (H-MRS). Recent studies showed measurements of 2HG at 7T with substantial gain in signal to noise ratio (SNR) and spectral resolution, offering higher specificity and sensitivity for 2HG detection. In this study, we assessed the sensitivity of semi-localized by adiabatic selective refocusing (sLASER) and J-difference MEsher-GArwood-semi-LASER (MEGA-sLASER) for 2HG detection at 7T.

View Article and Find Full Text PDF

Background: Despite the widespread knowledge about social support and health, there is little information about the association between social support and HIV risk behaviors such as condom use among female sex workers (FSWs) in Iran. This study aimed to determine the association between social support and frequency of condom use among FSWs in Tehran, Iran.

Methods: Using mixed sampling methods, we recruited 170 FSWs in Tehran in 2017.

View Article and Find Full Text PDF