J.A.W.M. van der Laak
Radboud University Nijmegen
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Featured researches published by J.A.W.M. van der Laak.
The Journal of Nuclear Medicine | 2014
A van Berkel; J.U. Rao; Benno Küsters; T. Demir; Eric J. W. Visser; Arjen R. Mensenkamp; J.A.W.M. van der Laak; Egbert Oosterwijk; J.W.M. Lenders; Fred C.G.J. Sweep; R.A. Wevers; A.R.M.M. Hermus; Johan F. Langenhuijsen; D.P.M. Kunst; Karel Pacak; Martin Gotthardt; Henri Timmers
Pheochromocytomas and paragangliomas (PPGLs) can be localized by 18F-FDG PET. The uptake is particularly high in tumors with an underlying succinate dehydrogenase (SDH) mutation. SDHx-related PPGLs are characterized by compromised oxidative phosphorylation and a pseudohypoxic response, which mediates an increase in aerobic glycolysis, also known as the Warburg effect. The aim of this study was to explore the hypothesis that increased uptake of 18F-FDG in SDHx-related PPGLs is reflective of increased glycolytic activity and is correlated with expression of different proteins involved in glucose uptake and metabolism through the glycolytic pathway. Methods: Twenty-seven PPGLs collected from patients with hereditary mutations in SDHB (n = 2), SDHD (n = 3), RET (n = 5), neurofibromatosis 1 (n = 1), and myc-associated factor X (n = 1) and sporadic patients (n = 15) were investigated. Preoperative 18F-FDG PET/CT studies were analyzed; mean and maximum standardized uptake values (SUVs) in manually drawn regions of interest were calculated. The expression of proteins involved in glucose uptake (glucose transporters types 1 and 3 [GLUT-1 and -3, respectively]), phosphorylation (hexokinases 1, 2, and 3 [HK-1, -2, and -3, respectively]), glycolysis (monocarboxylate transporter type 4 [MCT-4]), and angiogenesis (vascular endothelial growth factor [VEGF], CD34) were examined in paraffin-embedded tumor tissues using immunohistochemical staining with peroxidase-catalyzed polymerization of diaminobenzidine as a read-out. The expression was correlated with corresponding SUVs. Results: Both maximum and mean SUVs for SDHx-related tumors were significantly higher than those for sporadic and other hereditary tumors (P < 0.01). The expression of HK-2 and HK-3 was significantly higher in SDHx-related PPGLs than in sporadic PPGLs (P = 0.022 and 0.025, respectively). The expression of HK-2 and VEGF was significantly higher in SDHx-related PPGLs than in other hereditary PPGLs (P = 0.039 and 0.008, respectively). No statistical differences in the expression were observed for GLUT-1, GLUT-3, and MCT-4. The percentage anti-CD 34 staining and mean vessel perimeter were significantly higher in SDHx-related PPGLs than in sporadic tumors (P = 0.050 and 0.010, respectively). Mean SUVs significantly correlated with the expression of HK-2 (P = 0.027), HK-3 (P = 0.013), VEGF (P = 0.049), and MCT-4 (P = 0.020). Conclusion: The activation of aerobic glycolysis in SDHx-related PPGLs is associated with increased 18F-FDG accumulation due to accelerated glucose phosphorylation by hexokinases rather than increased expression of glucose transporters.
Oral Oncology | 2013
Théke J.H. Siebers; V.E. Bergshoeff; Irene Otte-Höller; Bernd Kremer; Ernst J. M. Speel; J.A.W.M. van der Laak; M.A.W. Merkx; Pieter J. Slootweg
OBJECTIVESnOne of the main problems in reducing the incidence of oral squamous cell carcinoma (OSCC) is the inability to appropriately deal with leukoplakia. Accurately identifying lesions which will progress to malignancy is currently not possible. The present study aims to establish the value of chromosome instability (CI) detection by DNA image cytometry and FISH analysis for prognosis and monitoring of oral leukoplakia.nnnMATERIALS AND METHODSnFor this purpose, we included from our archives 102 oral leukoplakia cases, which had been diagnosed between 1991 and 2008. Patient follow-up data were collected and the histopathological diagnosis was revised. CI assessment was carried out on paraffin-embedded tissue sections using both DNA image cytometry (ICM) and dual target FISH for chromosomes 1 and 7.nnnRESULTSn16 of 102 Patients developed carcinoma in situ or OSCC. Both detection methods were found to yield prognostic information independent of the histopathological diagnosis. CI was a strong individual marker of progression, with hazard ratios (HRs) of 7.2 and 6.8 for ICM and FISH respectively. Moreover, this approach seems suitable for monitoring lesions over time (especially ICM). Combining histopathology and CI enables subdivision of patients into three risk groups, with different probabilities of malignant progression.nnnCONCLUSIONnCI detection seems a reliable method for risk assessment of oral premalignancies and its application may contribute to a better risk-counselling and appropriate treatment regimen or watchfull-waiting approach of patients.
Journal of Neuro-oncology | 2004
H.J. Gilhuis; J.A.W.M. van der Laak; P. Wesseling; R.H. Boerman; G.N. Beute; J.L.J.M. Teepen; J.A. Grotenhuis; Arnoud C. Kappelle
AbstractObjective: The goal of our study was to investigate the inverse correlation between number of genetic aberrations and malignancy grade in ependymal tumors at the ploidy level.nMethods: we examined seven myxopapillary ependymomas (mpEs) (WHO grade I), 28 spinal and cerebral ependymomas (Es) (WHO grade II), and 18 cerebral anaplastic ependymomas (aEs) (WHO grade III) using image DNA cytometry. The ploidy status was correlated with clinicopathological characteristics and with the results obtained by comparative genomic hybridization (CGH) analysis that we performed in about half of these tumors.nResults: mpEs were exclusively located in the spinal cord and aEs in the cerebrum only, whereas Es were located in both the spinal cord and brain. We found aneuploidy or tetraploidy to be common in the group of mpEs (6 out of 7) and much less frequent in Es (6 out of 28) and aEs (4 out of 18). Three-year postoperative survival was 100% for mpEs, 100% for spinal Es, 92% for cerebral Es, and 33% for aEs. Our CGH results in a selection of these tumors revealed the highest number of genetic aberrations in the mpEs (average 16; n = 2), a lower number in Es (average 12; n = 11) and the lowest number in aEs (average 5; n = 6). Interestingly, in the group of Es and aEs, a high number of genetic aberrations as detected by CGH was not correlated with aneuploidy or tetraploidy. Three patients, all with mpEs had local seeding.nConclusion: These results underline that mpEs are distinctly different from Es and aEs at the genetic level and that extensive genomic alterations and aneuploidy in ependymal tumors are not in itself an indicator of malignant behavior.
Annals of Oncology | 2008
Marleen J.E.M. Gosens; Raphaëla C. Dresen; H.J.T. Rutten; G.A.P. Nieuwenhuijzen; J.A.W.M. van der Laak; Hendrik Martijn; Ivonne Tan-Go; Iris D. Nagtegaal; A. J. C. van den Brule; J.H.J.M. van Krieken
BACKGROUNDnNot all patients with locally advanced rectal cancer (LARC) respond equally to neo-adjuvant radiochemotherapy (RCT). Patients with highly apoptotic less advanced rectal cancers do not benefit from short-term radiotherapy. This study investigates whether this is also the case in the setting of RCT for LARC.nnnPATIENTS AND METHODSnTissue microarrays were constructed of biopsy and resection specimens of 201 LARC patients. Apoptosis (M30) and several apoptosis-regulating proteins [p53, Bcl-2, Bax, cyclooxygenase-2 (Cox-2) and mamma serine protease inhibitor (maspin)] were studied with immunohistochemistry. Subsequently, predictive values for local recurrence (LR), overall survival (OS) and histological tumour regression were analysed.nnnRESULTSnApoptotic levels, quantified as the number of apoptotic cells/mm(2) tumour epithelium, were higher in posttherapy tissues compared with biopsies (P < 0.001). Biopsies from clinical T4 stage tumours demonstrated significantly higher levels of apoptosis than clinical T3 stage tumours (P = 0.020). Therapy-induced apoptosis was higher when the interval between the last day of irradiation and surgery increased (P < 0.001, correlation coefficient = 0.355). Pre- and posttherapy apoptosis, p53, Bcl-2, Bax and Cox-2 were not associated with LR, OS or tumour regression. Intense pretherapy cytoplasmatic staining of maspin indicated a higher risk on LR (P = 0.009) only.nnnCONCLUSIONnCombined RCT is also successful in highly apoptotic tumours and is therefore independent of intrinsic apoptosis.
Radiology | 2016
Thiele Kobus; J.A.W.M. van der Laak; Marnix C. Maas; Thomas Hambrock; C.C. Bruggink; C.A. Hulsbergen-van de Kaa; Tom W. J. Scheenen; Arend Heerschap
PURPOSEnTo determine associations of metabolite levels derived from magnetic resonance (MR) spectroscopic imaging (ie, hydrogen 1 [(1)H] MR spectroscopic imaging) and apparent diffusion coefficients (ADCs) from diffusion-weighted imaging with prostate tissue composition assessed by digital image analysis of histologic sections.nnnMATERIALS AND METHODSnInstitutional ethical review board approved this retrospective study and waived informed consent. Fifty-seven prostate cancer patients underwent an MR examination followed by prostatectomy. One hematoxylin and eosin-stained section of the resected prostate per patient was digitized and computationally segmented into nuclei, lumen, and combination of epithelial cytoplasm and stroma. On each stained section, regions of interest (ROIs) were chosen and matched to the corresponding ADC map and (1)H MR spectroscopic imaging voxels. ADC and two metabolite ratios (citrate [Cit], spermine [Spm], and creatine [Cr] to choline [Cho] and Cho to Cr plus Spm) were correlated with percentage areas of nuclei, lumen, and cytoplasm and stroma for peripheral zone (PZ), transition zone (TZ), and tumor tissue in both zones of the prostate by using a linear mixed-effect model and Spearman correlation coefficient (ρ).nnnRESULTSnADC and (Cit + Spm + Cr)/Cho ratio showed positive correlation with percentage area of lumen (ρ = 0.43 and 0.50, respectively) and negative correlation with percentage area of nuclei (ρ = -0.29 and -0.26, respectively). The Cho/(Cr + Spm) ratio showed negative association with percentage area of lumen (ρ = -0.40) and positive association with area of nuclei (ρ = 0.26). Percentage areas of lumen and nuclei, (Cit + Spm + Cr)/Cho ratio, and ADC were significantly different (P < .001) between benign PZ (23.7 and 7.7, 8.83, and 1.58 × 10(-3) mm(2)/sec, respectively) and tumor PZ tissue (11.4 and 12.5, 5.13, and 1.20 × 10(-3) mm(2)/sec, respectively). These parameters were also significantly different between benign TZ (20.0 and 8.2, 6.50, and 1.26 × 10(-3) mm(2)/sec, respectively) and tumor TZ tissue (9.8 and 11.2, 4.36, and 1.03 × 10(-3) mm(2)/sec, respectively).nnnCONCLUSIONnThe observed correlation of (Cit + Spm + Cr)/Cho ratio and ADC of the prostate with its tissue composition indicates that components of this composition, such as percentage luminal area, contribute to the value of these MR parameters.
Acta Anaesthesiologica Scandinavica | 2015
S.E.I. van der Wal; Michiel Vaneker; M.A.H. Steegers; B.F.M. van Berkum; Matthijs Kox; J.A.W.M. van der Laak; J.G. van der Hoeven; Kris Vissers; Gert Jan Scheffer
Mechanical ventilation (MV) induces an inflammatory response that may result in (acute) lung injury. Lidocaine, an amide local anesthetic, has anti‐inflammatory properties in vitro and in vivo, possibly due to an attenuation of pro‐inflammatory cytokines, intracellular adhesion molecule‐1 (ICAM‐1), and reduction of neutrophils influx. We hypothesized an attenuation of MV‐induced inflammatory response with intravenously administered lidocaine.
Journal of Neuro-oncology | 1995
Pieter Wesseling; J.A.W.M. van der Laak; H. de Leeuw; Dirk J. Ruiter; Peter C. Burger
ConclusionsElucidation of the pathogenesis and biological significance of MVP in GBMs is essential for developing a rational treatment directed at the abrogation of neovascularization in these neoplasms. The present quantitative study illustrates the striking heterogeneity of the microvasculature in GBMs such that the number of vessels in many tumor areas does not exceed that of normal white matter. Thus, many regions of GBMs may not be overtly angiogenesis dependent and may be difficult to treat by anti-angiogenic therapy alone. Even in areas with florid MVP the efficacy of anti-angiogenic therapy is questionable since the contribution of these aberrant blood vessels to the functional circulation and thus to the viability and growth of GBMs is unclear.
Proceedings of SPIE | 2015
Geert J. S. Litjens; B. Ehteshami Bejnordi; Nadya Timofeeva; G. Swadi; I. Kovacs; C.A. Hulsbergen-van de Kaa; J.A.W.M. van der Laak
Automated detection of prostate cancer in digitized H and E whole-slide images is an important first step for computer-driven grading. Most automated grading algorithms work on preselected image patches as they are too computationally expensive to calculate on the multi-gigapixel whole-slide images. An automated multi-resolution cancer detection system could reduce the computational workload for subsequent grading and quantification in two ways: by excluding areas of definitely normal tissue within a single specimen or by excluding entire specimens which do not contain any cancer. In this work we present a multi-resolution cancer detection algorithm geared towards the latter. The algorithm methodology is as follows: at a coarse resolution the system uses superpixels, color histograms and local binary patterns in combination with a random forest classifier to assess the likelihood of cancer. The five most suspicious superpixels are identified and at a higher resolution more computationally expensive graph and gland features are added to refine classification for these superpixels. Our methods were evaluated in a data set of 204 digitized whole-slide H and E stained images of MR-guided biopsy specimens from 163 patients. A pathologist exhaustively annotated the specimens for areas containing cancer. The performance of our system was evaluated using ten-fold cross-validation, stratified according to patient. Image-based receiver operating characteristic (ROC) analysis was subsequently performed where a specimen containing cancer was considered positive and specimens without cancer negative. We obtained an area under the ROC curve of 0.96 and a 0.4 specificity at a 1.0 sensitivity.
GigaScience | 2018
Geert J. S. Litjens; Péter Bándi; B. Ehteshami Bejnordi; Oscar Geessink; Maschenka Balkenhol; Peter Bult; Altuna Halilovic; Meyke Hermsen; R.J.M. van de Loo; Rob Vogels; Quirine F. Manson; Nikolas Stathonikos; Alexi Baidoshvili; P. J. van Diest; C.A.P. Wauters; M van Dijk; J.A.W.M. van der Laak
Abstract Background The presence of lymph node metastases is one of the most important factors in breast cancer prognosis. The most common way to assess regional lymph node status is the sentinel lymph node procedure. The sentinel lymph node is the most likely lymph node to contain metastasized cancer cells and is excised, histopathologically processed, and examined by a pathologist. This tedious examination process is time-consuming and can lead to small metastases being missed. However, recent advances in whole-slide imaging and machine learning have opened an avenue for analysis of digitized lymph node sections with computer algorithms. For example, convolutional neural networks, a type of machine-learning algorithm, can be used to automatically detect cancer metastases in lymph nodes with high accuracy. To train machine-learning models, large, well-curated datasets are needed. Results We released a dataset of 1,399 annotated whole-slide images (WSIs) of lymph nodes, both with and without metastases, in 3 terabytes of data in the context of the CAMELYON16 and CAMELYON17 Grand Challenges. Slides were collected from five medical centers to cover a broad range of image appearance and staining variations. Each WSI has a slide-level label indicating whether it contains no metastases, macro-metastases, micro-metastases, or isolated tumor cells. Furthermore, for 209 WSIs, detailed hand-drawn contours for all metastases are provided. Last, open-source software tools to visualize and interact with the data have been made available. Conclusions A unique dataset of annotated, whole-slide digital histopathology images has been provided with high potential for re-use.
COMPAY/OMIA@MICCAI | 2018
T. de Bel; Meyke Hermsen; Geert J. S. Litjens; J.A.W.M. van der Laak
In renal transplantation pathology, the Banff grading system is used for diagnosis. We perform a case study on the detection of immune cells in tubules, with the goal of automating part of this grading. We propose a two-step approach, in which we first perform a structure segmentation and subsequently an immune cell detection. We used a dataset of renal allograft biopsies from the Radboud University Medical Centre, Nijmegen, the Netherlands. Our modified U-net reached a Dice score of 0.85 on the structure segmentation task. The F1-score of the immune cell detection was 0.33.