Follow-up Of Gliomas Research Articles

Role of Magnetic Resonance Imaging (MRI) in grading gliomas comparable with pathology: A cross-sectional study from Syria.

ObjectiveGliomas are one of the most common brain tumors in adults with a poor prognosis in most patients. Magnetic Resonance Imaging (MRI) plays a critical role in the diagnosis, management, and follow-up of gliomas. The aim of this study is to assess the sensitivity and specificity of MRI in the preoperative grading of supratentorial gliomas in comparison to histopathology.MethodsA cross-sectional study included 39 patients, aged between 40 and 75 years with histologically diagnosed supratentorial gliomas who underwent conventional MR imaging, which included T1, T2, and FLAIR sequences from November 2018–December 2019 in the Department of Neurosurgery, Tishreen University Hospital, Lattakia. The histopathological typing and grading of the tumor were done by using 2016 WHO classification. The sensitivity, specificity, predictive value, and accuracy of MRI in determining tumor grade were calculated. The comparison was done between MRI findings and WHO histopathological grading.ResultsThe overall sensitivity and specificity of MRI findings in the assessment of high-grade gliomas were 100% and 91% respectively. The positive predictive value (PPV) was 66.6%, and the negative predictive value (NPV) was 100%. The overall accuracy was 94.9%. The agreement between histopathological and MRI findings was 72%.ConclusionsMRI plays an essential role in the initial diagnosis and grading of supratentorial gliomas with high sensitivity and specificity. It is considered a non-invasive method and is useful in cases where the biopsy procedure is a contraindication or rejected by the patient.

Magnetic Resonance Spectroscopy in Diagnosis and Follow-Up of Gliomas: State-of-the-Art.

Simple SummaryMagnetic resonance spectroscopy (MRS) is a useful technique in diagnosis and follow-up of gliomas. In this review we provide an insight in the use of both proton and phosphorous MRS in clinical and scientific every day practice.Preoperative grade prediction is important in diagnostics of glioma. Even more important can be follow-up after chemotherapy and radiotherapy of high grade gliomas. In this review we provide an overview of MR-spectroscopy (MRS), technical aspects, and different clinical scenarios in the diagnostics and follow-up of gliomas in pediatric and adult populations. Furthermore, we provide a recap of the current research utility and possible future strategies regarding proton- and phosphorous-MRS in glioma research.

The Use of 18F-FET-PET-MRI in Neuro-Oncology: The Best of Both Worlds-A Narrative Review.

Gliomas are the most frequent primary tumors of the brain. They can be divided into grade II-IV astrocytomas and grade II-III oligodendrogliomas, based on their histomolecular profile. The prognosis and treatment is highly dependent on grade and well-identified prognostic and/or predictive molecular markers. Multi-parametric MRI, including diffusion weighted imaging, perfusion, and MR spectroscopy, showed increasing value in the non-invasive characterization of specific molecular subsets of gliomas. Radiolabeled amino-acid analogues, such as 18F-FET, have also been proven valuable in glioma imaging. These tracers not only contribute in the diagnostic process by detecting areas of dedifferentiation in diffuse gliomas, but this technique is also valuable in the follow-up of gliomas, as it can differentiate pseudo-progression from real tumor progression. Since multi-parametric MRI and 18F-FET PET are complementary imaging techniques, there may be a synergistic role for PET-MRI imaging in the neuro-oncological imaging of primary brain tumors. This could be of value for both primary staging, as well as during treatment and follow-up.

Hybrid [18F]-F-DOPA PET/MRI Interpretation Criteria and Scores for Glioma Follow-up After Radiotherapy.

18F‑fluoro-L‑3,4‑dihydroxyphenylalanine positron emission tomography (F‑DOPA PET) is used in glioma follow-up after radiotherapy to discriminate treatment-related changes (TRC) from tumor progression (TP). We compared the performances of acombined PET and MRI analysis with F‑DOPA current standard of interpretation. We included 76consecutive patients showing at least one gadolinium-enhanced lesion on the T1‑w MRI sequence (T1G). Two nuclear medicine physicians blindly analyzed PET/MRI images. In addition to the conventional PET analysis, they looked for F‑DOPA uptake(s) outside T1G-enhanced areas (T1G/PET), in the white matter (WM/PET), for T1G-enhanced lesion(s) without sufficiently concordant F‑DOPA uptake (T1G+/PET), and F‑DOPA uptake(s) away from hemorrhagic changes as shown with asusceptibility weighted imaging sequence (SWI/PET). We measured lesions' F‑DOPA uptake ratio using healthy brain background (TBR) and striatum (T/S) as references, and lesions' perfusion with arterial spin labelling cerebral blood flow maps (rCBF). Scores were determined by logistic regression. 53and 23patients were diagnosed with TP and TRC, respectively. The accuracies were 74% for T/S, 76% for TBR, and 84% for rCBF, with best cut-off values of 1.3, 3.7 and 1.25, respectively. For hybrid variables, best accuracies were obtained with conventional analysis (82%), T1G+/PET (82%) and SWI/PET (81%). T1G+/PET, SWI/PET and rCBF ≥ 1.25 were selected to construct a3-point score. It outperformed conventional analysis and rCBF with an AUC of 0.94 and an accuracy of 87%. Our scoring approach combining F‑DOPA PET and MRI provided better accuracy than conventional PET analyses for distinguishing TP from TRC in our patients after radiation therapy.

Simultaneously acquired PET and ASL imaging biomarkers may be helpful in differentiating progression from pseudo-progression in treated gliomas.

The aim of this work was investigating the methods based on coupling cerebral perfusion (ASL) and amino acid metabolism ([18F]DOPA-PET) measurements to evaluate the diagnostic performance of PET/MRI in glioma follow-up. Images were acquired using a 3-T PET/MR system, on a prospective cohort of patients addressed for possible glioma progression. Data were preprocessed with statistical parametric mapping (SPM), including registration on T1-weighted images, spatial and intensity normalization, and tumor segmentation. As index tests, tumor isocontour maps of [18F]DOPA-PET and ASL T-maps were created and metabolic/perfusion abnormalities were evaluated with the asymmetry index z-score. SPM map analysis of significant size clusters and semi-quantitative PET and ASL map evaluation were performed and compared to the gold standard diagnosis. Lastly, ASL and PET topography of significant clusters was compared to that of the initial tumor. Fifty-eight patients with unilateral treated glioma were included (34 progressions and 24 pseudo-progressions). The tumor isocontour maps and T-maps showed the highest specificity (100%) and sensitivity (94.1%) for ASL and [18F]DOPA analysis, respectively. The sensitivity of qualitative SPM maps and semi-quantitative rCBF and rSUV analyses were the highest for glioblastoma. Tumor isocontour T-maps and combined analysis of CBF and [18F]DOPA-PET uptake allow achieving high diagnostic performance in differentiating between progression and pseudo-progression in treated gliomas. The sensitivity is particularly high for glioblastomas. • Applied separately, MRI and PET imaging modalities may be insufficient to characterize the brain glioma post-therapeutic profile. • Combined ASL and [18F]DOPA-PET map analysis allows differentiating between tumor progression and pseudo-progression.

Glioma imaging in Europe: A survey of 220 centres and recommendations for best clinical practice

ObjectivesAt 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.MethodsInvitations 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.ResultsResponses 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 minority of sites use a reporting template (23%).ConclusionClinical best practice recommendations for glioma imaging assessment are proposed and the current role of advanced MRI modalities in routine use is addressed.Key Points• We recommend the EORTC-NBTS protocol as the clinical standard glioma protocol.• Perfusion MRI is recommended for diagnosis and follow-up of glioma.• Use of advanced imaging could be promoted with increased education activities.• Most response assessment is currently performed qualitatively.• Reporting templates are not widely used, and could facilitate standardisation.

Imaging of gliomas at 1.5 and 3 Tesla - A comparative study

Glioma follow-up is based on MRI parameters, which are correlated with survival. Although established criteria are used to evaluate tumor response, radiological markers may be confounded by differences in instrumentation including the magnetic field strength. We assessed whether MRIs obtained at 3 Tesla (T) and 1.5T provided similar information. We retrospectively compared imaging features of 30 consecutive patients with WHO grades II and III gliomas who underwent MRI at 1.5T and 3T within a month of each other, without any clinical changes during the same period. We compared lesion volumes on fluid attenuation inversion recovery (FLAIR), ratio of cerebral blood volume (rCBV) on perfusion-weighted imaging, contrast-to-noise ratio (CNR) on FLAIR, and on post-gadolinium 3D T1-weighted sequences between 1.5T and 3T using intraclass correlation coefficient (ICC). Concordance between observers within and between modalities was evaluated using weighted-kappa coefficient (wκ). The mean ± SD delay between modalities (1.5T and 3T MRI) was 8.6 ± 5.6 days. Interobserver/intraobserver concordance for lesion volume was almost perfect for 1.5T (ICC = 0.96/0.97) and 3T (ICC = 0.99/0.98). Agreement between observers for contrast enhancement was excellent at 1.5T (wκ = 0.92) and 3T (wκ = 0.92). The tumor CNR was significantly higher for FLAIR at 1.5T (P < .001), but it was higher at 3T (P = .012) for contrast enhancement. Correlations between modalities for lesion volume (ICC = 0.97) and for rCBV values (ICC = 0.92) were almost perfect. In the follow-up of WHO grades II and III gliomas, 1.5T and 3T provide similar MRI features, suggesting that monitoring could be performed on either a 1.5 or a 3T MR magnet.

Treatment Monitoring in Gliomas

To evaluate whether dynamic susceptibility-weighted contrast-enhanced (DSC), dynamic contrast-enhanced (DCE), and proton spectroscopic imaging ((1)H-MRSI) can identify progression and predict treatment failure during follow-up before tumor size changes, contrast agent uptake, or when new lesions become obvious. The aim was also to find out which of the aforementioned techniques had the best diagnostic performance compared with each other and standard magnetic resonance imaging (MRI). Thirty-seven patients with gliomas (21 women, 16 men; mean age at inclusion, 48 ± 14 years [standard deviation]) were assessed prospectively by (1)H-MRSI (point-resolved spectroscopy), DCE, and DSC perfusion MRI, each after a single dose of gadobenate dimeglumine during follow-up. Histology was available in all cases (resection, N = 18; biopsy, N = 19). All patients with low-grade gliomas (n = 20) did not receive any radio- or chemotherapy after partial resection (n = 7) or biopsy (n = 13), whereas 17 patients with high-grade gliomas had received adjuvant radiotherapy immediately after surgery. Tumor progression (progressive disease, PD) was defined as increase in longest glioma diameter by at least 20% (Response Evaluation Criteria in Solid Tumors), appearance of new lesions, or new contrast-enhancement. DSC, DCE, and MRSI image analyses comprised a detailed semiquantitative region of interest (ROI) analysis of the different parameters. Wilcoxon signed-rank test, Wilcoxon rank sum test, and Cox regression were used for statistical analysis. The median follow-up time was 607 days. Twenty patients showed PD (54%), 8 of 20 with low-grade (40%) and 12 of 17 with high-grade gliomas (71%). In PD, significant positive differences between log2-transformed ROI ratios at the last measurement in comparison to the first measurement (baseline) could be detected for tumor blood flow (P < 0.006) and volume (P < 0.001) derived from DSC and for maximum choline within tumor tissue (P = 0.0029) and Cho/Cr (P = 0.032) but not choline/N-acetyl-aspartate (P = 0.37) derived from MRSI. In contrast, these parameters were not significantly higher at last measurement in stable disease. Also, the differences between last value and baseline were significantly different between PD and stable disease for tumor blood flow (P < 0.004) and volume (P < 0.002) as well as for maximum choline within tumor tissue (P = 0.0011). The best prognostic parameter for PD at Cox analysis was time-dependent difference to baseline of log2 of relative regional cerebral blood flow normalized on gray matter (hazard ratio, 2.67; 95% confidence interval, 1.25-6.08; P = 0.01), while a prognostic value of MRS parameters could not be demonstrated. DSC perfusion imaging can identify progression and can predict treatment failure during follow-up of gliomas with the best diagnostic performance.

Clinical significance of CT perfusion image on post-operative follow-up of glioma

Objective To assess the clinical value of multi-slice helical CT perfusion on the post-operative follow-up of glioma.Methods CT perfusion image was applied to 32 patients with glioma after operation.Various perfusion parameters,include cerebral blood volume(CBV),permeability surface(PS),relative cerebral blood volume(rCBV)and relative permeability surface(rPS)were measured on recurrent area,nonrecurrent area and normal cerebral area respectively.SPSS 12.0 statistical software was used.Independent t test was used to compare the differences.Results In the recurrent group(16 cases),the value of CBV in creased in 12 cases and was normal in the other 4 cases.The value of PS increased in all the cases of recurrent group.The value of rCBV exceeded 2.6 in 10 cases,among which the biggest value of rCBV was 4.01.The mean value of rCBV was 2.67 and the mean value of rPS was 6.32;In the non-recurrent group(16 cases),the value of CBV was nearly normal in 7 cases,increased in 2 cases and decreased in the remaining 7 cases.The value of PS was nearly normal in 11 case,decreased in 3 cases and increased in the remaining 2 cases.The values of rCBV were all less than 2.6 and the biggest value of rCBV was 2.14.The mean value of rCBV was 0.99 and the mean value of rPS was 1.42.The statistic significance was obtained for all the parameters when compared the recurrent group with the non-recurrent group(P＜0.01)and with the normal cerebral area(P＜0.01).When compared the non-recurrent group with the normal cerebral area,none of the parameters had statistic significance(P＞0.05);The statistic significance was obtained for rCBV and rPS when compared the recurrent group with the non-recurrent group(P＜0.01).Conclusion CT perfusion image is valuable in determining glioma recurrence after operation. Key words: Glioma ; Perfusion,regional ; Tomography,X-ray computed ; Follow-up studies ;

Troubles cognitifs dans les gliomes de grade II et III de l’adulte : à propos d’une série de 15 patients

Correlated with better follow-up of gliomas, cognitive disorders are increasingly studied. The aim of this study was to describe the cognitive disorders presented by these patients at baseline, before any treatment, and to evaluate the relations between cognitive disorders and return to work. A detailed neuropsychological evaluation was administrated to 15 newly diagnosed patients with a grade II or III glial tumor before any treatment. Patients also completed the quality of life and depression scales. All patients in our study presented with at least one failed cognitive domain during the detailed examination, while the scores on the MMSE scale were within the norm. The most deteriorated functions were divided attention and episodic verbal and nonverbal memory. Moreover, a significant link was found between the number of failed cognitive functions and quality of life. Cognitive disorders are frequent with glial tumors and impact patients' quality of life. Simple tests of global cognitive status are not sufficient to detect cognitive difficulties in these patients. Consequently, detailed and adapted neuropsychological assessment is necessary, especially to detect deteriorated problems with memory, divided attention, or processing speed in this population.