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Tumor segmentation: The impact of standardized signal intensity histograms in glioblastoma

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In silico oncology is anticipated to gain a more individualized treatment for patients with cancer. To run in silico oncology models data from individual patients are essential. The more and the more accurate these data are the more precise the results of the in silico oncology models will be. Imaging studies are used to calculate tumor volume and define vital, necrotic and cystic areas within a tumor. Though the visual interpretation of magnetic resonance (MR) images is based on qualitative observation of variation in signal intensity a correlation of signal intensities with histological features of a tumor is not possible. Quantitative methods are needed for reliable follow-up or inter-individual studies. Using DoctorEye tumors can be easily rendered and histograms of the signal intensities within a tumor as well as mean and median signal intensities are calculated. In gliomas the histogram of signal intensities of cerebrospinal fluid is used as a reference for standardization of signal intensities. Our results in gliomas suggest that these histograms add value for a better description of tumors for the use in insilico oncology models.
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... The addition of other MRI modalities into such an analysis is promising as found in other tumors like glioblastoma. 12 In addition, diffusion-weighted (DWI) MRI might help in distinguishing histological subtypes of Wilms' tumor as the apparent diffusion coefficient (ADC) is a measure of the magnitude of diffusion of water molecules, and thus inversely correlates with the cellularity of a tissue. 13 ...
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... In recent clinical work [25], it was shown that histograms of signal intensities between cerebrospinal fluid (CSF), vital tumor, necrotic and cystic areas within the tumor vary consistently with patient response to therapy in all modalities analyzed. Using this imaging biomarker information, it might become possible to describe quantitative histogram biomarker changes in the tumor during the follow-up of single patients that are correlated to treatment response or progression. ...
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Dear Sir, The frequent opportunities I have had of receiving pleasure from your writings and conversation, have induced me to prefer offering to the Royal Society through your medium, this Paper on Life Contingencies, which forms part of a continuation of my original paper on the same subject, published among the valuable papers of the Society, as by passing through your hands it may receive the advantage of your judgment.
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