23 research outputs found
MRI Based Response Assessment and Diagnostics in Glioma
Gliomas are primary brain tumors in adults and are categorized by the World Health Organization (WHO) as grade I and II (low-grade gliomas), grade III (anaplastic) and IV (glioblastoma). Glioblastoma encompass 15% of all brain and central nervous system tumors and almost half of all primary brain tumors. Astrocytoma and glioblastoma are categorized by the mutational status of the gene encoding for isocitrate dehydrogenase (IDH): IDH-mutant (IDHmt) and IDH wild-type (IDHwt). By definition, oligodendroglioma is both 1p19q codeleted and IDHmt. While the exact diagnosis and tumor grade is determined by assessment of molecular markers and histology, Magnetic Resonance Imaging (MRI) can give information on the diagnosis as well. General features that can help predict glioma grade are presence or lack of contrast-enhancement and necrosis. More advanced measures such as Apparent Diffusion Coefficient (ADC) derived from Diffusion Weighted Imaging (DWI) and regional cerebral blood volume (rCBV) from perfusion imaging can also have added value and are therefore often included in clinical glioma scanning protocols
Evaluating glioma growth predictions as a forward ranking problem
The problem of tumor growth prediction is challenging, but promising results
have been achieved with both model-driven and statistical methods. In this
work, we present a framework for the evaluation of growth predictions that
focuses on the spatial infiltration patterns, and specifically evaluating a
prediction of future growth. We propose to frame the problem as a ranking
problem rather than a segmentation problem. Using the average precision as a
metric, we can evaluate the results with segmentations while using the full
spatiotemporal prediction. Furthermore, by separating the model goodness-of-fit
from future predictive performance, we show that in some cases, a better fit of
model parameters does not guarantee a better the predictive power
Evaluating the predictive value of glioma growth models for low-grade glioma after tumor resection
Tumor growth models have the potential to model and predict the spatiotemporal evolution of glioma in individual patients. Infiltration of glioma cells is known to be faster along the white matter tracts, and therefore structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) can be used to inform the model. However, applying and evaluating growth models in real patient data is challenging. In this work, we propose to formulate the problem of tumor growth as a ranking problem, as opposed to a segmentation problem, and use the average precision (AP) as a performance metric. This enables an evaluation of the spatial pattern that does not require a volume cut-off value. Using the AP metric, we evaluate diffusion-proliferation models informed by structural MRI and DTI, after tumor resection. We applied the models to a unique longitudinal dataset of 14 patients with low-grade glioma (LGG), who received no treatment after surgical resection, to predict the recurrent tumor shape after tumor resection. The diffusion models informed by structural MRI and DTI showed a small but significant increase in predictive performance with respect to homogeneous isotropic diffusion, and the DTI-informed model reached the best predictive performance. We conclude there is a significant improvement in the prediction of the recurrent tumor shape when using a DTI-informed anisotropic diffusion model with respect to istropic diffusion, and that the AP is a suitable metric to evaluate these models. All code and data used in this publication are made publicly available.</p
Glioma imaging in Europe: A survey of 220 centres and recommendations for best clinical practice
Objectives: At a European Society of Neuroradiology (ESNR) Annual Meeting 2015 workshop, commonalities in practice, current controversies and technical hurdles in glioma MRI were discussed. We aimed to formulate guidance on MRI of glioma and determine its feasibility, by seeking information on glioma imaging practices from the European Neuroradiology community. Methods: Invitations to a structured survey were emailed to ESNR members (n=1,662) and associates (n=6,400), European national radiologists’ societies and distributed via social media. Results: Responses were received from 220 institutions (59% academic). Conventional imaging protocols generally include T2w, T2-FLAIR, DWI, and pre- and post-contrast T1w. Perfusion MRI is used widely (85.5%), while spectroscopy seems reserved for specific indications. Reasons for omitting advanced imaging modalities include lack of facility/software, time constraints and no requests. Early postoperative MRI is routinely carried out by 74% within 24–72 h, but only 17% report a percent measure of resection. For follow-up, most sites (60%) issue qualitative reports, while 27% report an assessment according to the RANO criteria. A minori
Federated learning enables big data for rare cancer boundary detection.
Although machine learning (ML) has shown promise across disciplines, out-of-sample generalizability is concerning. This is currently addressed by sharing multi-site data, but such centralization is challenging/infeasible to scale due to various limitations. Federated ML (FL) provides an alternative paradigm for accurate and generalizable ML, by only sharing numerical model updates. Here we present the largest FL study to-date, involving data from 71 sites across 6 continents, to generate an automatic tumor boundary detector for the rare disease of glioblastoma, reporting the largest such dataset in the literature (n = 6, 314). We demonstrate a 33% delineation improvement for the surgically targetable tumor, and 23% for the complete tumor extent, over a publicly trained model. We anticipate our study to: 1) enable more healthcare studies informed by large diverse data, ensuring meaningful results for rare diseases and underrepresented populations, 2) facilitate further analyses for glioblastoma by releasing our consensus model, and 3) demonstrate the FL effectiveness at such scale and task-complexity as a paradigm shift for multi-site collaborations, alleviating the need for data-sharing
Author Correction: Federated learning enables big data for rare cancer boundary detection.
10.1038/s41467-023-36188-7NATURE COMMUNICATIONS14
Federated Learning Enables Big Data for Rare Cancer Boundary Detection
Although machine learning (ML) has shown promise across disciplines, out-of-sample generalizability is concerning. This is currently addressed by sharing multi-site data, but such centralization is challenging/infeasible to scale due to various limitations. Federated ML (FL) provides an alternative paradigm for accurate and generalizable ML, by only sharing numerical model updates. Here we present the largest FL study to-date, involving data from 71 sites across 6 continents, to generate an automatic tumor boundary detector for the rare disease of glioblastoma, reporting the largest such dataset in the literature (n = 6, 314). We demonstrate a 33% delineation improvement for the surgically targetable tumor, and 23% for the complete tumor extent, over a publicly trained model. We anticipate our study to: 1) enable more healthcare studies informed by large diverse data, ensuring meaningful results for rare diseases and underrepresented populations, 2) facilitate further analyses for glioblastoma by releasing our consensus model, and 3) demonstrate the FL effectiveness at such scale and task-complexity as a paradigm shift for multi-site collaborations, alleviating the need for data-sharing
Fundraising und Governance
Fundraising wird vornehmlich als operative Aufgabe der Kommunikation und Generierung von Mitteln verstanden. Die strategische Verankerung von Fundraising in der Organisation und der Abgleich mit den Organisationszielen wird dagegen nur selten behandelt. Dieses Kapitel stellt eine Verbindung zwischen Governance und Fundraising her und zwar hinsichtlich der Rolle des Vorstandes im Fundraising sowie der Reduzierung möglicher Risiken bei der Annahme von Spenden