Keywords:
Neuro, CNS, Neuroradiology brain, MR, MR-Diffusion/Perfusion, MR-Spectroscopy, Biopsy, Radiobiology, Staging, Cancer, Gene therapy, Molecular, genomics and proteomics, Prospective, Observational, Performed at one institution
Authors:
A. J. BARRIOS LOPEZ, A. Palpán Flores, C. Viváncos Sánchez, E. Lanz Santos, F. García Martínez, J. M. Roda Frade, G. Garzón Moll, A. ROYO OREJAS, C. Utrilla Contreras; Madrid/ES
DOI:
10.26044/ecr2020/C-07601
Methods and materials
This is a prospective observational study. There were 147 consecutive patients with diffuse gliomas of the central nervous system in total, between January 2015 and December 2018. The inclusion criteria were:
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A diagnostic MRI (1.5T or 3T system) study that includes: diffusion-weighted imaging with a b-value of 1000 s/mm2 and ADC map, post-contrast imaging, perfusion (Dynamic Susceptibility Contrast and Arterial Spin Labelling) and spectroscopy (CSI and Single-voxel spectroscopy).
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Resection surgery and chemoradiotherapy treatment, according to their histopathology and genetics.
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Genetic analysis that includes: Isocitrate-dehydrogenase-1 (IDH1) mutation, 1p/19q codeletion, O6-methylguanine-DNA-methyltransferase (MGMT) methylation and alpha-thalassemia-X-linked (ATRX) mutation status.
The exclusion criteria were:
Finally, 94 patients were excluded from the study and 53 remained.
The clinical information of the patients including age, gender, and survival, as well as the histopathology and genetics of the tumours, were recorded. MRI-based morphological features were also reported. A region of interest was placed in the tumour on the ADC maps to obtain the lowest ADC value and on perfusion MRI (DSC) to get a ratio of maximum relative cerebral blood volume (rCBVmax). This was carefully performed to avoid cystic or necrotic parts and large vessels. The presence of a trace with dominant peaks of choline and lipids/lactate on single-voxel spectroscopy and on multi-voxel chemical shift imaging was registered.
For statistical analysis, ISPSS Statistics 23 was used. In order to estimate the accuracy of each imaging finding to predict IDH mutation status, the area under the curve (AUC) was calculated using receiver operating characteristic (ROC) analysis. P-value of less than 0.05 was considered to indicate a statistically significant difference. The Kaplan-Meier survival analysis was used to estimate the OS of patients with wild-type diffuse gliomas and the log-rank test to compare the survival of methylated-MGMT GB versus unmethylated-MGMT GB patients. Finally, Cox (Proportional Hazards) Regression was employed to detect clinical, imaging and genomic prognostic factors of OS.