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"Tonn, Jörg-Christian"
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Joint EANM/EANO/RANO practice guidelines/SNMMI procedure standards for imaging of gliomas using PET with radiolabelled amino acids and 18FFDG: version 1.0
by
Law, Ian
,
Drzezga, Alexander
,
Lopci, Egesta
in
Amino acids
,
Brain
,
Clinical practice guidelines
2019
These joint practice guidelines, or procedure standards, were developed collaboratively by the European Association of Nuclear Medicine (EANM), the Society of Nuclear Medicine and Molecular Imaging (SNMMI), the European Association of Neurooncology (EANO), and the working group for Response Assessment in Neurooncology with PET (PET-RANO). Brain PET imaging is being increasingly used to supplement MRI in the clinical management of glioma. The aim of these standards/guidelines is to assist nuclear medicine practitioners in recommending, performing, interpreting and reporting the results of brain PET imaging in patients with glioma to achieve a high-quality imaging standard for PET using FDG and the radiolabelled amino acids MET, FET and FDOPA. This will help promote the appropriate use of PET imaging and contribute to evidence-based medicine that may improve the diagnostic impact of this technique in neurooncological practice. The present document replaces a former version of the guidelines published in 2006 (Vander Borght et al. Eur J Nucl Med Mol Imaging. 33:1374–80, 2006), and supplements a recent evidence-based recommendation by the PET-RANO working group and EANO on the clinical use of PET imaging in patients with glioma (Albert et al. Neuro Oncol. 18:1199–208, 2016). The information provided should be taken in the context of local conditions and regulations.
Journal Article
5-Aminolevulinic Acid-derived Tumor Fluorescence: The Diagnostic Accuracy of Visible Fluorescence Qualities as Corroborated by Spectrometry and Histology and Postoperative Imaging
2014
BACKGROUND:5-Aminolevulinic acid is used for fluorescence-guided resections. During resection, different macroscopic fluorescence qualities (“strong,” “weak”) can be distinguished that help guide resections.
OBJECTIVE:This prospective study was designed to assess the reliability of visible fluorescence qualities by spectrometry, pathology, and imaging.
METHODS:Thirty-three patients with malignant gliomas received 5-aminolevulinic acid (20 mg/kg). After debulking surgery, standardized biopsies were obtained from tissues with “weak” and “strong” fluorescence and from nonfluorescing near and distant brain for blinded assessment of cell density and tissue type (necrosis, solid or infiltrating tumor, normal tissue). The positive predictive value was calculated. Unresected fluorescing tissue was navigated for blinded correlation to postoperative magnetic resonance imaging (MRI). Receiver operating characteristic curves were generated for assessing the classification efficiency of spectrometry.
RESULTS:“Strong” fluorescence corresponded to greater spectrometric fluorescence, solidly proliferating tumor, and high cell densities, whereas “weak” fluorescence corresponded to lower spectrometric fluorescence, infiltrating tumor, and medium cell densities. The positive predictive value was 100% in strongly fluorescing tissue and 95% in weakly fluorescing tissue. Spectrometric fluorescence was detected in marginal tissue without macroscopic fluorescence. Depending on the threshold, spectrometry displayed greater sensitivity but lower specificity (accuracy 88.4%). Residual MRI enhancement in the tumor bed was detected in 15 of 23 (65%) patients with residual fluorescence, but in none of the patients without residual fluorescence.
CONCLUSION:Macroscopic fluorescence qualities predict solid and infiltrating tumor, providing useful information during resection. Fluorescence appears superior to contrast enhancement on MRI for indicating residual tumor. Spectrometry, on the other hand, is more sensitive but less specific, depending on threshold definition.
ABBREVIATIONS:5-ALA, 5-aminolevulinic acidCI, confidence intervalgamma-GT, gamma-glutamyl transpeptidaseGBM, glioblastoma multiformeNPV, negative predictive valuePPIX, protoporphyrin IXPPV, positive predictive valueSD, standard deviationWHO, World Health Organization
Journal Article
Simpson Grade Revisited – Intraoperative Estimation of the Extent of Resection in Meningiomas Versus Postoperative Somatostatin Receptor Positron Emission Tomography/Computed Tomography and Magnetic Resonance Imaging
by
Siller, Sebastian
,
Schichor, Christian
,
Vettermann, Franziska Jill
in
Adult
,
Aged
,
Brain cancer
2021
Abstract
BACKGROUND
Surgeon's intraoperative estimation of meningioma extent of resection (Simpson Grade, SG) is widely used as a prognostic factor for recurrence. However, the validity of SG is still a matter of debate. In preoperative imaging, 68Ga-DOTATATE/PET-CT has been shown to detect meningioma tissue even more sensitively than magnetic resonance imaging (MRI).
OBJECTIVE
To evaluate the Simpson grading within the framework of modern postoperative imaging techniques (MRI; PET-CT).
METHODS
At first, patients with WHO grade I meningioma, surgical resection, and postoperative 68Ga-DOTATATE/PET-CT within 6 mo after surgery were retrospectively analyzed. Second, an analogous prospective cohort of patients with WHO grade I meningioma was investigated by comparing SG after meningioma removal with postoperative MRI and 68Ga-DOTATATE/PET-CT within 6 mo after surgery.
RESULTS
A total of 37 patients were retrospectively analyzed. In total, 5/8 patients with SG-I and II resections showed tumor remnants according to postoperative PET-CT (SG 62.5% false negative). In the prospective cohort of 52 tumors, PET-CT displayed tracer uptake in 15/37 SG-I or II resections indicating unexpected tumor remnants (SG 40.5% false negative). MRI was false negative in 7 of these 15 cases (MRI 18.9% false negative) (P = .037). Discordant results according to PET-CT were more often found in convexity (40%) and falcine (46.7%) meningiomas than in skull base meningiomas (18.2%).
CONCLUSION
Intraoperative Simpson grading is at risk to underestimate tumor remnants, predominantly in grade I and II resections. Postoperative PET-CT improves detection rates compared to MRI. Prognostic impact of postoperative meningioma remnants according to PET-CT needs to be investigated prospectively.
Journal Article
Lomustine-temozolomide combination therapy versus standard temozolomide therapy in patients with newly diagnosed glioblastoma with methylated MGMT promoter (CeTeG/NOA–09): a randomised, open-label, phase 3 trial
by
Schnell, Oliver
,
Goldbrunner, Roland
,
Stummer, Walter
in
Adult
,
Aged
,
Antineoplastic Agents, Alkylating - therapeutic use
2019
There is an urgent need for more effective therapies for glioblastoma. Data from a previous unrandomised phase 2 trial suggested that lomustine-temozolomide plus radiotherapy might be superior to temozolomide chemoradiotherapy in newly diagnosed glioblastoma with methylation of the MGMT promoter. In the CeTeG/NOA-09 trial, we aimed to further investigate the effect of lomustine-temozolomide therapy in the setting of a randomised phase 3 trial.
In this open-label, randomised, phase 3 trial, we enrolled patients from 17 German university hospitals who were aged 18–70 years, with newly diagnosed glioblastoma with methylated MGMT promoter, and a Karnofsky Performance Score of 70% and higher. Patients were randomly assigned (1:1) with a predefined SAS-generated randomisation list to standard temozolomide chemoradiotherapy (75 mg/m2 per day concomitant to radiotherapy [59–60 Gy] followed by six courses of temozolomide 150–200 mg/m2 per day on the first 5 days of the 4-week course) or to up to six courses of lomustine (100 mg/m2 on day 1) plus temozolomide (100–200 mg/m2 per day on days 2–6 of the 6-week course) in addition to radiotherapy (59–60 Gy). Because of the different schedules, patients and physicians were not masked to treatment groups. The primary endpoint was overall survival in the modified intention-to-treat population, comprising all randomly assigned patients who started their allocated chemotherapy. The prespecified test for overall survival differences was a log-rank test stratified for centre and recursive partitioning analysis class. The trial is registered with ClinicalTrials.gov, number NCT01149109.
Between June 17, 2011, and April 8, 2014, 141 patients were randomly assigned to the treatment groups; 129 patients (63 in the temozolomide and 66 in the lomustine-temozolomide group) constituted the modified intention-to-treat population. Median overall survival was improved from 31·4 months (95% CI 27·7–47·1) with temozolomide to 48·1 months (32·6 months–not assessable) with lomustine-temozolomide (hazard ratio [HR] 0·60, 95% CI 0·35–1·03; p=0·0492 for log-rank analysis). A significant overall survival difference between groups was also found in a secondary analysis of the intention-to-treat population (n=141, HR 0·60, 95% CI 0·35–1·03; p=0·0432 for log-rank analysis). Adverse events of grade 3 or higher were observed in 32 (51%) of 63 patients in the temozolomide group and 39 (59%) of 66 patients in the lomustine-temozolomide group. There were no treatment-related deaths.
Our results suggest that lomustine-temozolomide chemotherapy might improve survival compared with temozolomide standard therapy in patients with newly diagnosed glioblastoma with methylated MGMT promoter. The findings should be interpreted with caution, owing to the small size of the trial.
German Federal Ministry of Education and Research.
Journal Article
Prediction of TERTp-mutation status in IDH-wildtype high-grade gliomas using pre-treatment dynamic 18FFET PET radiomics
by
Quach, Stefanie
,
Herms Jochen
,
Li, Zhicong
in
Confidence intervals
,
Feature extraction
,
Glioma
2021
PurposeTo evaluate radiomic features extracted from standard static images (20–40 min p.i.), early summation images (5–15 min p.i.), and dynamic [18F]FET PET images for the prediction of TERTp-mutation status in patients with IDH-wildtype high-grade glioma.MethodsA total of 159 patients (median age 60.2 years, range 19–82 years) with newly diagnosed IDH-wildtype diffuse astrocytic glioma (WHO grade III or IV) and dynamic [18F]FET PET prior to surgical intervention were enrolled and divided into a training (n = 112) and a testing cohort (n = 47) randomly. First-order, shape, and texture radiomic features were extracted from standard static (20–40 min summation images; TBR20–40), early static (5–15 min summation images; TBR5–15), and dynamic (time-to-peak; TTP) images, respectively. Recursive feature elimination was used for feature selection by 10-fold cross-validation in the training cohort after normalization, and logistic regression models were generated using the radiomic features extracted from each image to differentiate TERTp-mutation status. The areas under the ROC curve (AUC), accuracy, sensitivity, specificity, and positive and negative predictive value were calculated to illustrate diagnostic power in both the training and testing cohort.ResultsThe TTP model comprised nine selected features and achieved highest predictability of TERTp-mutation with an AUC of 0.82 (95% confidence interval 0.71–0.92) and sensitivity of 92.1% in the independent testing cohort. Weak predictive capability was obtained in the TBR5–15 model, with an AUC of 0.61 (95% CI 0.42–0.80) in the testing cohort, while no predictive power was observed in the TBR20–40 model.ConclusionsRadiomics based on TTP images extracted from dynamic [18F]FET PET can predict the TERTp-mutation status of IDH-wildtype diffuse astrocytic high-grade gliomas with high accuracy preoperatively.
Journal Article
Poor prognosis associated with TERT gene alterations in meningioma is independent of the WHO classification: an individual patient data meta-analysis
by
Law, Ian
,
Spiegl-Kreinecker, Sabine
,
Poulsgaard, Lars
in
alteration
,
Binding sites
,
Brain cancer
2020
Background TERT gene alterations (TERT-alt) have been linked to increased risk of recurrence in meningiomas, whereas the association to mortality largely remain incompletely investigated. As incongruence between clinical course and WHO grade exists, reliable biomarkers have been sought.MethodsWe applied the Preferred Reporting Items for Systematic Review and Meta-Analyses of individual participant data Statement. We compiled data from eight studies and allocated patients to TERT-alt (n=59) or TERT promoter wild-type (TERTp-wt; n=618). We compared the two groups stratified for WHO grades as: incidence rates, survival probabilities and cumulative recurrences. We estimated the effects of WHO grade, age at diagnosis and sex as HRs.Results TERT-alt occurred in 4.7%, 7.9% and 15.4% of WHO-I/WHO-II/WHO-III meningiomas, respectively. The median recurrence-free survival was 14 months for all TERT-alt patients versus 101 months for all TERTp-wt patients. The HR for TERT-alt was 3.74 in reference to TERTp-wt. For all TERT-alt patients versus all TERTp-wt patients, the median overall survival was 58 months and 160 months, respectively. The HR for TERT-alt was 2.77 compared with TERTp-wt. TERT-alt affected prognosis independent of WHO grades. Particularly, the recurrence rate was 4.8 times higher in WHO-I/-II TERT-alt patients compared with WHO-III TERTp-wt patients. The mortality rate was 2.7 times higher in the WHO-I and WHO-II TERT-alt patients compared with WHO-III TERTp-wt patients.Conclusions TERT-alt is an important biomarker for significantly higher risk of recurrence and death in meningiomas. TERT-alt should be managed and surveilled aggressively. We propose that TERT-alt analysis should be implemented as a routine diagnostic test in meningioma and integrated into the WHO classification.Trial registration numberPROSPERO: CRD42018110566.
Journal Article
Injury-specific factors in the cerebrospinal fluid regulate astrocyte plasticity in the human brain
by
Masserdotti, Giacomo
,
Götz, Magdalena
,
Delbridge, Claire
in
631/378/1689
,
631/532/2182
,
Animal models
2023
The glial environment influences neurological disease progression, yet much of our knowledge still relies on preclinical animal studies, especially regarding astrocyte heterogeneity. In murine models of traumatic brain injury, beneficial functions of proliferating reactive astrocytes on disease outcome have been unraveled, but little is known regarding if and when they are present in human brain pathology. Here we examined a broad spectrum of pathologies with and without intracerebral hemorrhage and found a striking correlation between lesions involving blood–brain barrier rupture and astrocyte proliferation that was further corroborated in an assay probing for neural stem cell potential. Most importantly, proteomic analysis unraveled a crucial signaling pathway regulating this astrocyte plasticity with GALECTIN3 as a novel marker for proliferating astrocytes and the GALECTIN3-binding protein LGALS3BP as a functional hub mediating astrocyte proliferation and neurosphere formation. Taken together, this work identifies a therapeutically relevant astrocyte response and their molecular regulators in different pathologies affecting the human cerebral cortex.
Intracerebral hemorrhage triggers astrocyte proliferation and mediates neural stem cell potential via Galectin3 signaling.
Journal Article
Deep-learning-based reconstruction of undersampled MRI to reduce scan times: a multicentre, retrospective, cohort study
by
Bendszus, Martin
,
Rastogi, Aditya
,
Deike-Hofmann, Katerina
in
Accuracy
,
Artificial Intelligence
,
Biomarkers
2024
The extended acquisition times required for MRI limit its availability in resource-constrained settings. Consequently, accelerating MRI by undersampling k-space data, which is necessary to reconstruct an image, has been a long-standing but important challenge. We aimed to develop a deep convolutional neural network (dCNN) optimisation method for MRI reconstruction and to reduce scan times and evaluate its effect on image quality and accuracy of oncological imaging biomarkers.
In this multicentre, retrospective, cohort study, MRI data from patients with glioblastoma treated at Heidelberg University Hospital (775 patients and 775 examinations) and from the phase 2 CORE trial (260 patients, 1083 examinations, and 58 institutions) and the phase 3 CENTRIC trial (505 patients, 3147 examinations, and 139 institutions) were used to develop, train, and test dCNN for reconstructing MRI from highly undersampled single-coil k-space data with various acceleration rates (R=2, 4, 6, 8, 10, and 15). Independent testing was performed with MRIs from the phase 2/3 EORTC-26101 trial (528 patients with glioblastoma, 1974 examinations, and 32 institutions). The similarity between undersampled dCNN-reconstructed and original MRIs was quantified with various image quality metrics, including structural similarity index measure (SSIM) and the accuracy of undersampled dCNN-reconstructed MRI on downstream radiological assessment of imaging biomarkers in oncology (automated artificial intelligence-based quantification of tumour burden and treatment response) was performed in the EORTC-26101 test dataset. The public NYU Langone Health fastMRI brain test dataset (558 patients and 558 examinations) was used to validate the generalisability and robustness of the dCNN for reconstructing MRIs from available multi-coil (parallel imaging) k-space data.
In the EORTC-26101 test dataset, the median SSIM of undersampled dCNN-reconstructed MRI ranged from 0·88 to 0·99 across different acceleration rates, with 0·92 (95% CI 0·92–0·93) for 10-times acceleration (R=10). The 10-times undersampled dCNN-reconstructed MRI yielded excellent agreement with original MRI when assessing volumes of contrast-enhancing tumour (median DICE for spatial agreement of 0·89 [95% CI 0·88 to 0·89]; median volume difference of 0·01 cm3 [95% CI 0·00 to 0·03] equalling 0·21%; p=0·0036 for equivalence) or non-enhancing tumour or oedema (median DICE of 0·94 [95% CI 0·94 to 0·95]; median volume difference of –0·79 cm3 [95% CI –0·87 to –0·72] equalling –1·77%; p=0·023 for equivalence) in the EORTC-26101 test dataset. Automated volumetric tumour response assessment in the EORTC-26101 test dataset yielded an identical median time to progression of 4·27 months (95% CI 4·14 to 4·57) when using 10-times-undersampled dCNN-reconstructed or original MRI (log-rank p=0·80) and agreement in the time to progression in 374 (95·2%) of 393 patients with data. The dCNN generalised well to the fastMRI brain dataset, with significant improvements in the median SSIM when using multi-coil compared with single-coil k-space data (p<0·0001).
Deep-learning-based reconstruction of undersampled MRI allows for a substantial reduction of scan times, with a 10-times acceleration demonstrating excellent image quality while preserving the accuracy of derived imaging biomarkers for the assessment of oncological treatment response. Our developments are available as open source software and hold considerable promise for increasing the accessibility to MRI, pending further prospective validation.
Deutsche Forschungsgemeinschaft (German Research Foundation) and an Else Kröner Clinician Scientist Endowed Professorship by the Else Kröner Fresenius Foundation.
Journal Article
Detection of impending perfusion deficits by intraoperative computed tomography (iCT) in aneurysm surgery of the anterior circulation
2021
Background
The aim of our study was to evaluate the additional benefit of intraoperative computed tomography (iCT), intraoperative computed tomography angiography (iCTA), and intraoperative computed tomography perfusion (iCTP) in the intraoperative detection of impending ischemia to established methods (indocyanine green videoangiography (ICGVA), microDoppler, intraoperative neuromonitoring (IONM)) for initiating timely therapeutic measures.
Methods
Patients with primary aneurysms of the anterior circulation between October 2016 and December 2019 were included. Data of iCT modalities compared to other techniques (ICGVA, microDoppler, IONM) was recorded with emphasis on resulting operative conclusions leading to inspection of clip position, repositioning, or immediate initiation of conservative treatment strategies. Additional variables analyzed included patient demographics, aneurysm-specific characteristics, and clinical outcome.
Results
Of 194 consecutive patients, 93 patients with 100 aneurysms received iCT imaging. While IONM and ICGVA were normal, an altered vessel patency in iCTA was detected in 5 (5.4%) and a mismatch in iCTP in 7 patients (7.5%). Repositioning was considered appropriate in 2 patients (2.2%), where immediate improvement in iCTP could be documented. In a further 5 cases (5.4%), intensified conservative therapy was immediately initiated treating the reduced CBP as clip repositioning was not considered causal. In terms of clinical outcome at last FU, mRS0 was achieved in 85 (91.4%) and mRS1-2 in 7 (7.5%) and remained mRS4 in one patient with SAH (1.1%).
Conclusions
Especially iCTP can reveal signs of impending ischemia in selected cases and enable the surgeon to promptly initiate therapeutic measures such as clip repositioning or intraoperative onset of maximum conservative treatment, while established tools might fail to detect those intraoperative pathologic changes.
Journal Article
Outcome after individualized stereoelectroencephalography (sEEG) implantation and navigated resection in patients with lesional and non-lesional focal epilepsy
by
Thorsteinsdottir, Jun
,
Vollmar, Christian
,
Jörg-Christian Tonn
in
Brain mapping
,
Computed tomography
,
Convulsions & seizures
2019
BackgroundRefined localization of the epileptogenic zone (EZ) in patients with pharmacoresistant focal epilepsy proceeding to resective surgery might improve postoperative outcome. We here report seizure outcome after stereo EEG (sEEG) evaluation with individually planned stereotactically implanted depth electrodes and subsequent tailored resection.MethodsA cohort of consecutive patients with pharmacoresistant focal epilepsy, evaluated with a non-invasive evaluation protocol and invasive monitoring with personalized, stereotactically implanted depth electrodes for sEEG was analyzed. Co-registration of post-implantation CT scan to presurgical MRI data was used for 3D reconstructions of the patients’ brain surface and mapping of neurophysiology data. Individual multimodal 3D maps of the EZ were used to guide subsequent tailored resections. The outcome was rated according to the Engel classification.ResultsOut of 914 patients who underwent non-invasive presurgical evaluation, 85 underwent sEEG, and 70 were included in the outcome analysis. Median follow-up was 31.5 months. Seizure-free outcome (Engel class I A-C, ILAE class 1–2) was achieved in 83% of the study cohort. Patients exhibiting lesional and non-lesional (n = 42, 86% vs. n = 28, 79%), temporal and extratemporal (n = 45, 80% vs. n = 25, 84%), and right- and left-hemispheric epilepsy (n = 44, 82% vs. n = 26, 85%) did similarly well. This remains also true for those with an EZ adjacent to or distant from eloquent cortex (n = 21, 86% vs. n = 49, 82%). Surgical outcome was independent of resected tissue volume.ConclusionFavourable post-surgical outcome can be achieved in patients with resistant focal epilepsy, using individualized sEEG evaluation and tailored navigated resection, even in patients with non-lesional or extratemporal focal epilepsy.
Journal Article