32 results on '"Richard Drexler"'
Search Results
2. Machine learning based outcome prediction of microsurgically treated unruptured intracranial aneurysms
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Nico Stroh, Harald Stefanits, Alexander Maletzky, Sophie Kaltenleithner, Stefan Thumfart, Michael Giretzlehner, Richard Drexler, Franz L. Ricklefs, Lasse Dührsen, Stefan Aspalter, Philip Rauch, Andreas Gruber, and Matthias Gmeiner
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Medicine ,Science - Abstract
Abstract Machine learning (ML) has revolutionized data processing in recent years. This study presents the results of the first prediction models based on a long-term monocentric data registry of patients with microsurgically treated unruptured intracranial aneurysms (UIAs) using a temporal train-test split. Temporal train-test splits allow to simulate prospective validation, and therefore provide more accurate estimations of a model’s predictive quality when applied to future patients. ML models for the prediction of the Glasgow outcome scale, modified Rankin Scale (mRS), and new transient or permanent neurological deficits (output variables) were created from all UIA patients that underwent microsurgery at the Kepler University Hospital Linz (Austria) between 2002 and 2020 (n = 466), based on 18 patient- and 10 aneurysm-specific preoperative parameters (input variables). Train-test splitting was performed with a temporal split for outcome prediction in microsurgical therapy of UIA. Moreover, an external validation was conducted on an independent external data set (n = 256) of the Department of Neurosurgery, University Medical Centre Hamburg-Eppendorf. In total, 722 aneurysms were included in this study. A postoperative mRS > 2 was best predicted by a quadratic discriminant analysis (QDA) estimator in the internal test set, with an area under the receiver operating characteristic curve (ROC-AUC) of 0.87 ± 0.03 and a sensitivity and specificity of 0.83 ± 0.08 and 0.71 ± 0.07, respectively. A Multilayer Perceptron predicted the post- to preoperative mRS difference > 1 with a ROC-AUC of 0.70 ± 0.02 and a sensitivity and specificity of 0.74 ± 0.07 and 0.50 ± 0.04, respectively. The QDA was the best model for predicting a permanent new neurological deficit with a ROC-AUC of 0.71 ± 0.04 and a sensitivity and specificity of 0.65 ± 0.24 and 0.60 ± 0.12, respectively. Furthermore, these models performed significantly better than the classic logistic regression models (p 2, a pre- and postoperative difference in mRS > 1 point and a GOS
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- 2023
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3. Expertise in surgical neuro-oncology. Results of a survey by the EANS neuro-oncology section
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K. Gousias, A. Hoyer, L.A. Mazurczyk, J. Bartek, Jr., M. Bruneau, E. Celtikci, N. Foroglou, C. Freyschlag, R. Grossman, C. Jungk, P. Metellus, D. Netuka, R. Rola, P. Schucht, C. Senft, F. Signorelli, A.J.P.E. Vincent, M. Simon, Rachit Agrawal, Luigi Albano, George A. Alexiou, Amanj Ali, Rafid Al-Mahfoudh, Michael Amoo, Christos Anagnostopoulos, Sven Bamps, Soham Bandyopadhyay, Damiano G. Barone, Fabio Barone, Sami Barrit, Felix Behling, Alin Blaga, Alexandros Boukas, Paul Brennan, Vicki M. Butenschoen, Mauro Campello, Areda Cara, Salvatore Chibbaro, Robert Chrenko, Pere J. Cifre Serra, Hans Clusmann, Alba Corell, Jan F. Cornelius, Marcello D'Andrea, Andreas K. Demetriades, Steven De Vleeschouwer, Richard Drexler, Johnny Duerinck, Ruben V. Fanarjyan, Alejandro Fernandez-Coello, Kostas Fountas, Thomas M. Freiman, Vadim Gadzhiagaev, Miltiadis Georgiopoulos, Nathalie Gilis, Jagos Golubovic, Eric Goulin Lippi Fernandes, Giovanni Grasso, Francesco Guerrini, Beste Gulsuna, Ciaran S. Hill, Julius Höhne, Markus Holling, Ievgenii Iarmoliuk, Florian Ioan-Alexandru, Tamara Ius, Kestutis Jacikevicius, Asgeir S. Jakola, Paweł Jakubowski, Georgios Kalantzis, Konstantina Karabatsou, Ramez Kirollos, Ralph König, Danil A. Kozyrev, Dietmar Krex, Barbara Ladisich, Ruth Lau, Yauhen Lizunou, Arnaud Lombard, Hu Liang Low, José Luís Alves, Yazid Maghrabi, Marco Mammi, Ala Marji, Luca Massimi, Ioannis Mavridis, Aaron Lawson McLean, Anna C. Lawson McLean, Bernhard Meyer, Malte Mohme, Pedro Moura Branco, Michael Müther, Issam Musleh, Danial Nasiri, Ramon Navarro, Ibrahim Omerhodzic, Marvin Darkwah Oppong, Nikolaos A. Paidakakos, Zoi Pantera, Mohammed A. Patel, Mateusz Pawlowski, Athanasios Petridis, Adrian J. Praeger, Stephen Price, Franz Ricklefs, Luigi Rigante, Florian Ringel, Pierre A. Robe, Karl Rössler, Eduarda Sá-Marta, Jose L. Sanmillan, Alba Scerrati, Matthias Schneider, Henry W.S. Schroeder, Michael Schwake, Mohamed Shoaib, Octavian Mihai Sirbu, Iñigo L. Sistiaga, Tomasz J. Skajster, Albertas Sliauzys, Vitaly Sokotukhin, Jehuda Soleman, Veit M. Stoecklein, Eric Suero Molina, Wojciech Świątnicki, Νikolaos Syrmos, Graziano Taddei, Avin Taher, Martin Tamarit, Mark ter Laan, Theocharis Theocharous, Dieter Thijs, Leonidas Trakolis, Monica Truffelli, Miriam Weiss, Eberhard Uhl, Laura Grazia Valentini, Dimitri Vanhauwaert, Bassel Zebian, Bojana Zivkovic, and Matteo Zoli
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Expertise ,Surgical neuro-oncology ,EANS ,CNS tumors ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Introduction: Technical advances and the increasing role of interdisciplinary decision-making may warrant formal definitions of expertise in surgical neuro-oncology. Research question: The EANS Neuro-oncology Section felt that a survey detailing the European neurosurgical perspective on the concept of expertise in surgical neuro-oncology might be helpful. Material and methods: The EANS Neuro-oncology Section panel developed an online survey asking questions regarding criteria for expertise in neuro-oncological surgery and sent it to all individual EANS members. Results: Our questionnaire was completed by 251 respondents (consultants: 80.1%) from 42 countries. 67.7% would accept a lifetime caseload of >200 cases and 86.7% an annual caseload of >50 as evidence of neuro-oncological surgical expertise. A majority felt that surgeons who do not treat children (56.2%), do not have experience with spinal fusion (78.1%) or peripheral nerve tumors (71.7%) may still be considered experts. Majorities believed that expertise requires the use of skull-base approaches (85.8%), intraoperative monitoring (83.4%), awake craniotomies (77.3%), and neuro-endoscopy (75.5%) as well as continuing education of at least 1/year (100.0%), a research background (80.0%) and teaching activities (78.7%), and formal interdisciplinary collaborations (e.g., tumor board: 93.0%). Academic vs. non-academic affiliation, career position, years of neurosurgical experience, country of practice, and primary clinical interest had a minor influence on the respondents’ opinions. Discussion and conclusion: Opinions among neurosurgeons regarding the characteristics and features of expertise in neuro-oncology vary surprisingly little. Large majorities favoring certain thresholds and qualitative criteria suggest a consensus definition might be possible.
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- 2024
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4. Impact of the SARS-CoV-2 pandemic on the survival of patients with high-grade glioma and best practice recommendations
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Marco M. E. Vogel, Arthur Wagner, Jens Gempt, Harald Krenzlin, Thomas Zeyen, Richard Drexler, Martin Voss, Charlotte Nettekoven, Tammam Abboud, Dorothee Mielke, Veit Rohde, Marco Timmer, Roland Goldbrunner, Joachim P. Steinbach, Lasse Dührsen, Manfred Westphal, Ulrich Herrlinger, Florian Ringel, Bernhard Meyer, and Stephanie E. Combs
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Medicine ,Science - Abstract
Abstract The severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) has changed the clinical day-to-day practice. The aim of this study was to evaluate the impact of the pandemic on patients with high-grade glioma (HGG) as well as to derive best practice recommendations. We compared a multi-institutional cohort with HGG (n = 251) from 03/2020 to 05/2020 (n = 119) to a historical cohort from 03/2019 to 05/2019 (n = 132). The endpoints were outcome (progression-free survival (PFS) and overall survival (OS)) as well as patterns of care and time intervals between treatment steps. The median OS for WHO grade 4 gliomas was 12 months in 2019 (95% Confidence Interval 9.7–14.3 months), and not reached in 2020 (p = .026). There were no other significant differences in the Kaplan–Meier estimates for OS and PFS between cohorts of 2019 and 2020, neither did stratification by WHO grade reveal any significant differences for OS, PFS or for patterns of care. The time interval between cranial magnetic resonance imaging (cMRI) and biopsy was significantly longer in 2020 cohort (11 versus 21 days, p = .031). Median follow-up was 10 months (range 0–30 months). Despite necessary disease containment policies, it is crucial to ensure that patients with HGG are treated in line with the recent guidelines and standard of care (SOC) algorithms. Therefore, we strongly suggest pursuing no changes to SOC treatment, a timely diagnosis and treatment with short time intervals between first symptoms, initial diagnosis, and treatment, as well as a guideline-based cMRI follow-up.
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- 2023
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5. Enhancing Safety in Epilepsy Surgery (EASINESS): Study Protocol for a Retrospective, Multicenter, Open Registry
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Richard Drexler, Sharona Ben-Haim, Christian G. Bien, Valeri Borger, Francesco Cardinale, Alexandre Carpentier, Fernando Cendes, Sarat Chandra, Hans Clusmann, Albert Colon, Marco de Curtis, Daniel Delev, Giuseppe Didato, Lasse Dührsen, Jibril Osman Farah, Marc Guenot, Saadi Ghatan, Claire Haegelen, Hajo Hamer, Jason S. Hauptmann, Rosalind L. Jeffree, Thilo Kalbhenn, Josua Kegele, Niklaus Krayenbühl, Johannes Lang, Bertrand Mathon, Georgios Naros, Julia Onken, Fedor Panov, Christian Raftopoulos, Franz L. Ricklefs, Kim Rijkers, Michele Rizzi, Karl Rössler, Olaf Schijns, Ulf C. Schneider, Andrea Spyrantis, Adam Strzelczyk, Stefan Stodieck, Manjari Tripathi, Sumeet Vadera, Mario A. Alonso-Vanegas, José Géraldo Ribero Vaz, Jörg Wellmer, Tim Wehner, Manfred Westphal, and Thomas Sauvigny
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epilepsy ,epilepsy surgery ,temporal lobe epilepsy ,outcome ,benchmark ,seizure outcome ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Introduction: Optimizing patient safety and quality improvement is increasingly important in surgery. Benchmarks and clinical quality registries are being developed to assess the best achievable results for several surgical procedures and reduce unwarranted variation between different centers. However, there is no clinical database from international centers for establishing standardized reference values of patients undergoing surgery for mesial temporal lobe epilepsy.Design: The Enhancing Safety in Epilepsy Surgery (EASINESS) study is a retrospectively conducted, multicenter, open registry. All patients undergoing mesial temporal lobe epilepsy surgery in participating centers between January 2015 and December 2019 are included in this study. The patient characteristics, preoperative diagnostic tools, surgical data, postoperative complications, and long-term seizure outcomes are recorded.Outcomes: The collected data will be used for establishing standardized reference values (“benchmarks”) for this type of surgical procedure. The primary endpoints include seizure outcomes according to the International League Against Epilepsy (ILAE) classification and defined postoperative complications.Discussion: The EASINESS will define robust and standardized outcome references after amygdalohippocampectomy for temporal lobe epilepsy. After the successful definition of benchmarks from an international cohort of renowned centers, these data will serve as reference values for the evaluation of novel surgical techniques and comparisons among centers for future clinical trials.Clinical trial registration: This study is indexed at clinicaltrials.gov (NT 04952298).
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- 2021
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6. Targeted anticonvulsive treatment of IDH-wildtype glioblastoma based on DNA methylation subclasses
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Richard Drexler, Jennifer Göttsche, Thomas Sauvigny, Ulrich Schüller, Robin Khatri, Fabian Hausmann, Sonja Hänzelmann, Tobias B Huber, Stefan Bonn, Dieter H Heiland, Daniel Delev, Varun Venkataramani, Frank Winkler, Johannes Weller, Thomas Zeyen, Ulrich Herrlinger, Jens Gempt, Franz L Ricklefs, and Lasse Dührsen
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Cancer Research ,Oncology ,Neurology (clinical) - Published
- 2023
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7. Epigenetic profiling reveals a strong association between lack of 5-ALA fluorescence and EGFR amplification in IDH-wildtype glioblastoma
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Richard Drexler, Thomas Sauvigny, Ulrich Schüller, Alicia Eckhardt, Cecile L Maire, Robin Khatri, Fabian Hausmann, Sonja Hänzelmann, Tobias B Huber, Stefan Bonn, Helena Bode, Katrin Lamszus, Manfred Westphal, Lasse Dührsen, and Franz L Ricklefs
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Medicine (miscellaneous) - Abstract
Background 5-aminolevulinic acid (5-ALA) fluorescence-guided resection increases the percentage of complete CNS tumor resections and improves the progression-free survival of IDH-wildtype glioblastoma patients. A small subset of IDH-wildtype glioblastoma shows no 5-ALA fluorescence. An explanation for these cases is missing. In this study, we used DNA methylation profiling to further characterize non-fluorescent glioblastomas. Methods Patients with newly diagnosed and recurrent IDH-wildtype glioblastoma that underwent surgery were analyzed. The intensity of intraoperative 5-ALA fluorescence was categorized as non-visible or visible. DNA was extracted from tumors and genome-wide DNA methylation patterns were analyzed using Illumina EPIC (850k) arrays. Furthermore, 5-ALA intensity was measured by flow cytometry on human gliomasphere lines (BT112 and BT145). Results Of 74 included patients, 12 (16.2%) patients had a non-fluorescent glioblastoma, which were compared to 62 glioblastomas with 5-ALA fluorescence. Clinical characteristics were equally distributed between both groups. We did not find significant differences between DNA methylation subclasses and 5-ALA fluorescence (P = .24). The distribution of cells of the tumor microenvironment was not significantly different between the non-fluorescent and fluorescent tumors. Copy number variations in EGFR and simultaneous EGFRvIII expression were strongly associated with 5-ALA fluorescence since all non-fluorescent glioblastomas were EGFR-amplified (P < .01). This finding was also demonstrated in recurrent tumors. Similarly, EGFR-amplified glioblastoma cell lines showed no 5-ALA fluorescence after 24 h of incubation. Conclusions Our study demonstrates an association between non-fluorescent IDH-wildtype glioblastomas and EGFR gene amplification which should be taken into consideration for recurrent surgery and future studies investigating EGFR-amplified gliomas.
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- 2023
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8. DNA methylation subclass receptor tyrosine kinase II (RTK II) is predictive for seizure development in glioblastoma patients
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Franz L Ricklefs, Richard Drexler, Kathrin Wollmann, Alicia Eckhardt, Dieter H Heiland, Thomas Sauvigny, Cecile Maire, Katrin Lamszus, Manfred Westphal, Ulrich Schüller, and Lasse Dührsen
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Cancer Research ,Oncology ,Brain Neoplasms ,Seizures ,Basic and Translational Investigations ,Humans ,Receptor Protein-Tyrosine Kinases ,Anticonvulsants ,Neurology (clinical) ,DNA Methylation ,Glioblastoma - Abstract
Background Seizures can present at any time before or after the diagnosis of a glioma. Roughly, 25%–30% of glioblastoma (GBM) patients initially present with seizures, and an additional 30% develop seizures during the course of the disease. Early studies failed to show an effect of general administration of antiepileptic drugs for glioblastoma patients, since they were unable to stratify patients into high- or low-risk seizure groups. Methods 111 patients, who underwent surgery for a GBM, were included. Genome-wide DNA methylation profiling was performed, before methylation subclasses and copy number changes inferred from methylation data were correlated with clinical characteristics. Independently, global gene expression was analyzed in GBM methylation subclasses from TCGA datasets (n = 68). Results Receptor tyrosine Kinase (RTK) II GBM showed a significantly higher incidence of seizures than RTK I and mesenchymal (MES) GBM (P < .01). Accordingly, RNA expression datasets revealed an upregulation of genes involved in neurotransmitter synapses and vesicle transport in RTK II glioblastomas. In a multivariate analysis, temporal location (P = .02, OR 5.69) and RTK II (P = .03, OR 5.01) were most predictive for preoperative seizures. During postoperative follow-up, only RTK II remained significantly associated with the development of seizures (P < .01, OR 8.23). Consequently, the need for antiepileptic medication and its increase due to treatment failure was highly associated with the RTK II methylation subclass (P < .01). Conclusion Our study shows a strong correlation of RTK II glioblastomas with preoperative and long-term seizures. These results underline the benefit of molecular glioblastoma profiling with important implications for postoperative seizure control.
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- 2022
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9. Single-Center Experience Using a 3D4K Digital Operating Scope System for Aneurysm Surgery
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Tobias, Pantel, Richard, Drexler, Jennifer, Göttsche, Andras, Piffko, Manfred, Westphal, Jan, Regelsberger, and Lasse, Dührsen
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Indocyanine Green ,Microsurgery ,Humans ,Intracranial Aneurysm ,Surgery ,Neurology (clinical) ,Cerebral Angiography ,Retrospective Studies - Abstract
In recent years, 3D4K exoscope systems (EXs) have been introduced to microneurosurgery and reported to be an alternative to conventional operating microscopes (OMs). This study reviews our single-center experience using an 3D4K EX in intracranial aneurysm surgery.To investigate the applicability of a novel 3D4K EX for intracranial aneurysm surgery.A retrospective analysis of patients who underwent microsurgical repair of incidentally or ruptured cerebral aneurysms between August 2018 and August 2020 was performed. Patient and aneurysm characteristics and technical features, including 3-dimensional indocyanine green fluorescence, were evaluated. Data on surgery duration were statically assessed for a time trend and comparability with the OM cohort.Overall, we collected 185 aneurysm cases in which the exoscope was used in 44 cases. The mean duration of surgery using the EX was in similar range to those using the OM (165.5 ± 45.8 minutes vs 160.5 ± 39.2 minutes, P.05). Routine postoperative computed tomography angiography showed comparable rates of complete aneurysm occlusion (95.5% vs 92.2%, P.05) and postoperative complications (9.1% vs 9.7%, P.05). There was no necessity to revert to the OM from the EX. Three-dimensional indocyanine green fluorescence was used in all procedures without any malfunction.The 3D4K EX for vascular microsurgical cases proved to be as useful as the OM. Because of the ease of use and comparable surgical results, the EX has the potential to become an accepted and additional visualization tool in vascular microsurgery next to the OM.
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- 2022
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10. The Comprehensive Complication Index (CCI) as a Measure of Postoperative Morbidity and Neurological Outcome after Elective Intracranial Surgery
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Richard, Drexler, Franz Lennard, Ricklefs, Tobias Fabian, Pantel, Jennifer, Göttsche, Manfred, Westphal, and L, Dührsen
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Surgery ,Neurology (clinical) - Abstract
Background: The Comprehensive Complication Index (CCI) is a numerical scale based on the Clavien-Dindo classification (CDC) and both are widely used to assess outcome. However, the CCI had not been described for neurosurgical procedures. Objective: We aimed to investigate the value of the CCI to predict outcome in patients who underwent elective intracranial surgery. Methods: Prospective cohort study including patients who underwent elective intracranial surgery. Complications were graded using CDC, and the CCI was calculated daily. Neurological outcome was assessed using mRS, NANO, NIHSS, and KPS. Results: Of 294 patients who underwent an elective intracranial procedure, 211 (71.8%) patients underwent a craniotomy, while 28 (9.5%) patients had a burr hole procedure and 55 (18.7%) patients a transsphenoidal approach. A higher blood loss was the only significant predictor for a higher CCI (OR 1.09, 95% CI 1.00-1.12, P < 0.01). Patients with a higher CCI had a longer LOS (mean: 5.4 versus 10.9 days, P < 0.01) and ICU stay (mean: 0.8 versus 2.4 days, P < 0.01). Daily CCI revealed a risk for complications after craniotomies until postoperative day (POD) 7. In patients who underwent brain tumor surgery, the resection of meningiomas and metastasis showed a similar developmental course of CCI. A significantly higher CCI was observed in patients who had a neurological deterioration at discharge ( P < 0.01). Conclusion: CCI is a valid scale to measure outcome after intracranial procedures and correlates with neurological outcome. Risk for adverse events after craniotomy is at highest until postoperative day 7.
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- 2022
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11. Impact of acute kidney injury after extended liver resections
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Richard Drexler, Martin Schneider, York von Rittberg, Tim Reese, Georgios Makridis, Karl J. Oldhafer, Fabian Kröger, Maximilian Stanley Jusufi, Kim C Wagner, and Roland Brüning
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medicine.medical_specialty ,Urology ,030230 surgery ,Liver resections ,urologic and male genital diseases ,03 medical and health sciences ,Postoperative Complications ,0302 clinical medicine ,Risk Factors ,Clinical endpoint ,medicine ,Hepatectomy ,Humans ,Risk factor ,Retrospective Studies ,Hepatology ,urogenital system ,business.industry ,Incidence ,Incidence (epidemiology) ,Liver Neoplasms ,Gastroenterology ,Acute kidney injury ,Perioperative ,Acute Kidney Injury ,medicine.disease ,female genital diseases and pregnancy complications ,030220 oncology & carcinogenesis ,Hepatocellular carcinoma ,business ,Kidney disease - Abstract
Background Complex liver resection is a risk factor for the development of AKI, which is associated with increased morbidity and mortality. Aim of this study was to assess risk factors for acute kidney injury (AKI) and its impact on outcome for patients undergoing complex liver surgery. Methods AKI was defined according to the KDIGO criteria. Primary endpoint was the occurrence of AKI after liver resection. Secondary endpoints were complications and mortality. Results Overall, 146 patients undergoing extended liver resection were included in the study. The incidence of AKI was 21%. The incidence of chronic kidney disease (CKD) and hepatocellular carcinoma were significantly higher in patients with AKI. In the AKI group, the proportion of extended right hepatectomies was the highest (53%), followed by ALPPS (43%). Increased intraoperative blood loss, increased postoperative complications and perioperative mortality was associated with AKI. Besides age and CKD, ALPPS was an independent risk factor for postoperative AKI. A small future liver remnant seemed to increase the risk of AKI in patients undergoing ALPPS. Conclusion Following extended liver resection, AKI is associated with an increased morbidity and mortality. ALPPS is a major independent risk factor for the development of AKI and a sufficient future liver remnant could avoid postoperative AKI.
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- 2021
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12. Association of subcellular localization of TEAD transcription factors with outcome and progression in pancreatic ductal adenocarcinoma
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Rebecca Fahy, Moritz Kleine, Tim Reese, Bernd Feyerabend, Kim C Wagner, Karl J. Oldhafer, Mareike Ehmke, Mirco Küchler, and Richard Drexler
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Adult ,Male ,Cytoplasm ,Endocrinology, Diabetes and Metabolism ,Kaplan-Meier Estimate ,Metastasis ,Cohort Studies ,03 medical and health sciences ,Pancreatectomy ,0302 clinical medicine ,Pancreatic cancer ,Biomarkers, Tumor ,Humans ,Medicine ,Neoplasm Metastasis ,TEAD3 ,TEAD2 ,TEAD1 ,Transcription factor ,Aged ,Aged, 80 and over ,Cell Nucleus ,Hepatology ,business.industry ,Gastroenterology ,Wnt signaling pathway ,TEA Domain Transcription Factors ,Middle Aged ,medicine.disease ,Immunohistochemistry ,Survival Analysis ,DNA-Binding Proteins ,Pancreatic Neoplasms ,030220 oncology & carcinogenesis ,Disease Progression ,Cancer research ,Female ,030211 gastroenterology & hepatology ,business ,Carcinoma, Pancreatic Ductal ,Subcellular Fractions ,Transcription Factors - Abstract
Background Transcriptional enhanced associated domain (TEAD) transcription factors are nuclear effectors of several oncogenic signalling pathways including Hippo, WNT, TGF-s and EGFR pathways that interact with various cancer genes. The subcellular localization of TEAD regulates the functional output of these pathways affecting tumour progression and patient outcome. However, the impact of the TEAD family on pancreatic ductal adenocarcinoma (PDAC) and its clinical progression remain elusive. Methods A cohort of 81 PDAC patients who had undergone surgery was established. Cytoplasmic and nuclear localization of TEAD1, TEAD2, TEAD3 and TEAD4 was evaluated with the immunoreactive score (IRS) by immunohistochemistry (IHC) using paraffin-embedded tissue. Results were correlated with clinicopathological data, disease-free and overall survival. Results Nuclear staining of all four TEADs was increased in pancreatic cancer tissue. Patients suffering from metastatic disease at time of surgery showed a strong nuclear staining of TEAD2 and TEAD3 (p cytoplasmic ratio of TEAD2 and TEAD3 was associated with a shorter overall survival and TEAD2 emerged as an independent prognostic factor for disease-free survival. Conclusion Our study underlines the importance of TEAD transcription factors in PDAC as a nuclear localization was found to be associated with metastatic disease and an unfavourable prognosis after surgical resection.
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- 2021
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13. Significance of unphosphorylated and phosphorylated heat shock protein 27 as a prognostic biomarker in pancreatic ductal adenocarcinoma
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Richard Drexler, Moritz Kleine, Karl J. Oldhafer, Kim C Wagner, Mirco Küchler, and Bernd Feyerabend
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Male ,Cancer Research ,medicine.medical_specialty ,animal structures ,Down-Regulation ,HSP27 ,Kaplan-Meier Estimate ,Deoxycytidine ,Gastroenterology ,Metastasis ,Hsp27 ,Internal medicine ,Pancreatic cancer ,Heat shock protein ,Biomarkers, Tumor ,medicine ,HSP ,Humans ,Phosphorylation ,Heat-Shock Proteins ,Aged ,Hematology ,biology ,business.industry ,Liver Neoplasms ,Biomarker ,General Medicine ,Middle Aged ,Prognosis ,medicine.disease ,Immunohistochemistry ,Gemcitabine ,Pancreatic Neoplasms ,Survival Rate ,Oncology ,Drug Resistance, Neoplasm ,biology.protein ,Biomarker (medicine) ,Female ,Original Article – Cancer Research ,business ,Carcinoma, Pancreatic Ductal ,Molecular Chaperones ,medicine.drug - Abstract
Purpose Few studies reported about the potential of unphosphorylated heat shock protein 27 (HSP27) and phosphorylated heat shock protein 27 (pHSP27) as a predictor for survival and gemcitabine resistance in pancreatic ductal adenocarcinoma (PDAC). In this study, we analysed the expression patterns of pHSP27 and HSP27 in a patient population after surgery and correlated the immunohistochemical results with clinicopathological data and long-term outcome of the patients. Methods HSP27 and pHSP27 (Ser-15, Ser-78 and Ser-82) protein expression were analysed by immunohistochemistry using the immunoreactive score (IRS) from paraffin-embedded tissue of 106 patients with PDAC who underwent surgery. Immunohistochemical results were correlated with clinicopathological data, disease-free (DFS) and overall survival (OS). Results HSP27 expression was significantly lower in patients with a shorter OS (p = 0.006) and DFS (p p = 0.001). Furthermore, HSP27 was downregulated in patients suffering from metastases at time of surgery (p p = 0.007). In contrast, pHSP27-Ser15, -Ser78 and -Ser82 were not associated with any survival data of the study population. Conclusion HSP27 seems to be a strong indicator for the prediction of OS and DFS. Moreover, HSP27 could play a role in the formation and migration of liver metastases of PDAC.
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- 2020
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14. DNA methylation subclasses predict the benefit from gross total tumor resection in IDH-wildtype glioblastoma patients
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Richard Drexler, Ulrich Schüller, Alicia Eckhardt, Katharina Filipski, Tabea I Hartung, Patrick N Harter, Iris Divé, Marie-Therese Forster, Marcus Czabanka, Claudius Jelgersma, Julia Onken, Peter Vajkoczy, David Capper, Christin Siewert, Thomas Sauvigny, Katrin Lamszus, Manfred Westphal, Lasse Dührsen, and Franz L Ricklefs
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Cancer Research ,Oncology ,Neurology (clinical) - Abstract
Background DNA methylation-based tumor classification allows an enhanced distinction into subgroups of glioblastoma. However, the clinical benefit of DNA methylation-based stratification of glioblastomas remains inconclusive. Methods Multicentric cohort study including 430 patients with newly diagnosed glioblastoma subjected to global DNA methylation profiling. Outcome measures included overall survival (OS), progression-free survival (PFS), prognostic relevance of EOR and MGMT promoter methylation status as well as a surgical benefit for recurrent glioblastoma. Results 345 patients (80.2%) fulfilled the inclusion criteria and 305 patients received combined adjuvant therapy. DNA methylation subclasses RTK I, RTK II, and mesenchymal (MES) revealed no significant survival differences (RTK I: Ref.; RTK II: HR 0.9 [95% CI, 0.64–1.28]; p = 0.56; MES: 0.69 [0.47–1.02]; p = 0.06). Patients with RTK I (GTR/near GTR: Ref.; PR: HR 2.87 [95% CI, 1.36–6.08]; p < 0.01) or RTK II (GTR/near GTR: Ref.; PR: HR 5.09 [95% CI, 2.80–9.26]; p < 0.01) tumors who underwent gross-total resection (GTR) or near GTR had a longer OS and PFS than partially resected patients. The MES subclass showed no survival benefit for a maximized EOR (GTR/near GTR: Ref.; PR: HR 1.45 [95% CI, 0.68–3.09]; p = 0.33). Therapy response predictive value of MGMT promoter methylation was evident for RTK I (HR 0.37 [95% CI, 0.19–0.71]; p < 0.01) and RTK II (HR 0.56 [95% CI, 0.34–0.91]; p = 0.02) but not the MES subclass (HR 0.52 [95% CI, 0.27–1.02]; p = 0.06). For local recurrence (n = 112), re-resection conveyed a progression-to-overall survival (POS) benefit (p < 0.01), which was evident in RTK I (p = 0.03) and RTK II (p < 0.01) tumors, but not in MES tumors (p = 0.33). Conclusion We demonstrate a survival benefit from maximized EOR for newly diagnosed and recurrent glioblastomas of the RTK I and RTK II but not the MES subclass. Hence, it needs to be debated whether the MES subclass should be treated with maximal surgical resection, especially when located in eloquent areas and at time of recurrence.
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- 2022
15. CTNI-07. LOMUSTINE/TEMOZOLOMIDE CHEMOTHERAPY FOR NEWLY DIAGNOSED MGMT-METHYLATED IDHWT GLIOBLASTOMA ACCORDING TO CETEG/NOA-09: REAL-WORLD EXPERIENCE IN A MULTICENTER COHORT
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Johannes Weller, Thomas Zeyen, Uwe Schlegel, Lazaros Lazaridis, Jan-Michael Werner, Julia Onken, Pia Zeiner, Richard Drexler, Peter Hau, Clemens Seidel, Lucia Grosse, Hans Clusmann, Michael Sabel, Florian Ringel, Josef Pichler, Oliver Grauer, Thomas Hundsberger, Oliver Schnell, Maximilian J Mair, Martin Uhl, Friederike Schmidt-Graf, Martin Glas, Norbert Galldiks, Meike Unteroberdörster, Joachim Steinbach, Franz Ricklefs, Mirjam Renovanz, Daniel Ivanov Delev, Merih O Turgut, Oliver R Flesch, Debora Cipriani, Matthias Preusser, Sied Kebir, Martin Misch, Roland Goldbrunner, Manfred Westphal, Ghazaleh Tabatabai, Niklas Schäfer, Matthias Schneider, Hartmut Vatter, Frank Giordano, Christina Schaub, and Ulrich Herrlinger
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Cancer Research ,Oncology ,Neurology (clinical) - Abstract
INTRODUCTION The CeTeG/NOA-09 trial demonstrated superior median overall survival (mOS, 48.1 months) in MGMT-methylated glioblastoma treated with lomustine/temozolomide compared to temozolomide. We retrospectively analyzed an off-study cohort of patients treated with lomustine/temozolomide to gather real-world data on this new regimen. METHODS Adult patients from 20 centers in Germany, Austria and Switzerland were included. Inclusion criteria were MGMT-methylated IDHwt glioblastoma newly diagnosed prior to end of 2020, and lomustine/temozolomide treatment as part of first-line therapy. RESULTS 321 patients with a median age of 57 years (range, 21-78) and a median follow-up of 19.9 months were included. In the whole cohort, mOS was 41.0 months (95%CI, 33.0 – not reached). In patients starting lomustine/temozolomide immediately upon initiation of radiotherapy strictly following the CeTeG protocol (88%), mOS was 52.8 months (35.8 – not reached) as compared to 24.6 months (17.6 – not reached) in patients starting lomustine/temozolomide after completion of radiotherapy/concomitant temozolomide (12%, logrank test: p = 0.06). Patients with a KPS < 80 had a shorter mOS of 19.7 months (95%CI, 16.6 – not reached) compared to 41.0 months (33.0 – not reached, p = 0.009) in KPS 80-100. Gross total resection (GTR, 53.9%) was associated with longer mOS (52.8 months, 95%CI 24.1 – not reached) compared to partial resection/biopsy (30.5 months, 95%CI 36.8 – not reached, p=0.004). Multivariable Cox regression analysis confirmed GTR (HR 0.66, p = 0.033) and younger age ( ≤ 50 years: HR 0.42, p = 0.001), but not KPS (80-100 vs. lower: HR 0.66, p = 0.12) as independent prognostic factors. DISCUSSION In this real-world multicenter cohort, survival was similar to the promising results of CeTeG/NOA-09. Further analyses should investigate a potentially reduced benefit from lomustine/temozolomide in patients with low KPS/no GTR and a possible detrimental effect from deferred lomustine/temozolomide initiation. The median follow-up is admittedly short, updated data will be presented.
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- 2022
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16. BIOM-32. DNA METHYLATION SUBCLASSES PREDICT THE BENEFIT FROM GROSS TOTAL TUMOR RESECTION IN IDH-WILDTYPE GLIOBLASTOMA PATIENTS
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Richard Drexler, Ulrich Schüller, Alicia Eckhardt, Katharina Filipski, Tabea Hartung, Patrick Harter, Iris Divé, Marie-therese Forster, Marcus Czabanka, Claudius Jelgersma, Julia Onken, Peter Vajkoczy, David Capper, Christin Siewert, Thomas Sauvigny, Katrin Lamszus, Manfred Westphal, Lasse Dührsen, and Franz Ricklefs
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Cancer Research ,Oncology ,Neurology (clinical) - Abstract
DNA methylation-based tumor classification allows an enhanced distinction into subgroups of glioblastoma. However, the clinical benefit of DNA methylation-based stratification of glioblastomas remains inconclusive. We performed a multicentric cohort study including 430 patients with newly diagnosed glioblastoma whose tumors were subjected to DNA methylation profiling. The primary outcome was overall survival (OS) and progression-free survival (PFS). Secondary outcomes were the prognostic relevance of EOR and MGMTpromoter methylation status as well as surgical benefit for recurrent glioblastoma. After stratifying patients in accordance with their DNA methylation subclasses RTK I, RTK II, and mesenchymal (MES), outcome analyses revealed no significant differences between these three methylation subclasses (p = 0.06). RTK I or RTK II tumors who underwent gross-total resection (GTR) or near GTR had a longer OS and PFS than partially resected patients (p < 0.01). In the MES subclass, no survival benefit for a maximized EOR was found (p = 0.33). In multivariate analysis, the therapy response-predictive value of MGMT promoter methylation was evident for RTK I (p < 0.01) and RTK II (p = 0.02) but failed to be an independent factor in the MES subclass (p= 0.06). For local recurrence, re-resection conveyed a progression-to-overall survival (POS) benefit (p < 0.01), which was evident in the RTK I (p = 0.03) and RTK II (p < 0.01) subclasses, but not in the MES subclass (p = 0.33).This study demonstrates a survival benefit from maximized EOR at surgery for newly diagnosed and recurrent glioblastomas of the RTK I and RTK II subclass but not the MES subclass. Hence, it needs to be carefully considered whether the MES subclass should be treated with maximal surgical resection, especially when located in eloquent areas and at time of recurrence.
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- 2022
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17. PATH-47. THE CHALLENGE AND THERAPEUTIC RELEVANCE OF A NON-MATCHING CLASSIFIER OUTPUT USING GENOME-WIDE DNA METHYLATION FOR CLINICAL ROUTINE
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Richard Drexler, Alicia Eckhardt, Helena Bode, Krystian Fita, Katrin Lamszus, Manfred Westphal, Lasse Dührsen, Ulrich Schüller, and Malte Mohme
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Cancer Research ,Oncology ,Neurology (clinical) - Abstract
DNA methylation-based classification of central nervous system tumours has been increasing in importance for routine clinical workups and offers novel opportunities in discriminating subtypes which could lead to a more customized therapy. However, there are still unclassifiable entities for which defining an effective therapeutic regimen is challenging. The aim of our study was to gain further insight in these challenging cases. We included 81 patients with a calibrated score below 0.9 in the classifier output, who underwent surgery for a tumour of the central nervous system (CNS). 47 patients had a different output using the classifier version v11b4 when compared to their histological diagnosis. Of these, 41 patients (87.2 %) did not have any diagnosis from the methylation classifier (“no matching methylation class”). Surgical and clinicopathological features as well as DNA input had no impact on the calibrated score. Cases with non-classifiable tumors had a significantly longer time until a decision for adjuvant therapy and these cases were presented more often in neurooncological tumor boards (p< 0.01). Further analyses in 23 glioblastoma patients revealed comparable results for the overall survival, but a significantly shorter progression-free survival in cases with a discrepancy between the histological and classifier diagnosis. Application of the latest classifier version v12.5 enabled classification in 67.9% of cases, resulting in re-classification with a high calibrated score (> 0.9) in 25.7% of the tumors. Taken together, our study presents unclassifiable cases and the possible clinical impact when waiting for the accurate diagnosis in these challenging cases. Even though DNA methylation profiling significantly contributes to advanced CNS tumour diagnostics, clinicians should be aware of a prolonged interval to treatment initiation, especially for highly malignant brain tumours. Therefore, we would recommend to schedule adjuvant treatment as early as possible if surgical and histological results are suspicious for this disease.
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- 2022
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18. BIOM-10. CIRCULATING EXTRACELLULAR VESICLES AS A TOOL FOR DIAGNOSIS, PROGNOSIS AND MONITORING IN GLIOMA
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Franz Ricklefs, Kathrin Wollmann, Cecile Maire, Richard Drexler, Manfred Westphal, Katrin Lamszus, and Lasse Dührsen
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Cancer Research ,Oncology ,Neurology (clinical) - Abstract
OBJECTIVE Extracellular vesicles (EVs) represent a population of lipid bilayer nanoparticles released by all cell types, including tumor cells that can serve as a noninvasive source for liquid biopsy. To date, MRI images have been the established method for monitoring treatment efficacy in brain tumor patients. We investigated the potential of pure EV count for diagnosis, prognosis, and treatment monitoring in gliomas. METHODS Plasma samples, differential blood counts, at multiple timepoints before and after surgery of glioblastoma patients (n=101) were collected. Follow-up samples were obtained every 3 months. Healthy donors served as controls (n=29). Plasma EVs concentration was measured by Nanoparticle Tracking Analysis (NTA). EVs were characterized by electron microscopy and imaging flow cytometry. Tumor burden was measured by MRI images. Clinical characteristics were prospectively recorderd. In addition plasma EVs from Mut3 tumor bearing mice were analysed at d3, d5, d7, d10, d12 after tumor injection (n=20). MRI images and differential blood counts were analyzed. RESULTS Glioblatoma patients have a 5-fold increase of plasma EVs compared to HD; p < 0.0001). Circulating EVs counts correlated only with FLAIR hyperintensity and with no other MRI or blood-based parameter. Similar results were obtained from Mut3 tumor mice. Dichotomisation of GBM patients in EVhigh and low revealed a significant overall survival and progression free survival benefit for EVlow patients (p=0.004). After surgery, EVs decreased significantly (5-fold, p< 0.0001). A massive drop in EVs was associated with gross-total resection (p < 0.05). At the time of tumor recurrence, the number of circulating EVs increased in all patients during a follow-up (9 months). CONCLUSION Our findings highlight the potential of circulating EVs as a biomarker tool for diagnosis, prognosis and treatment monitoring in GBM patietns, as they seem to reflect the presence of a tumor mass and thus may assist in clinical decision making.
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- 2022
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19. QLTI-09. DEFINING GLOBAL BENCHMARK OUTCOMES FOR TRANSSPHENOIDAL SURGERY OF PITUITARY ADENOMAS: A MULTICENTER ANALYSIS OF 2862 CASES
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Richard Drexler, Roman Rotermund, Timothy Smith, John Kilgallon, Jürgen Honegger, Isabella Nasi-Kordhishti, Paul Gardner, Zachary Gersey, Hussein Abdallah, John Jane, Alexandria Marino, Ulrich Knappe, Nesrin Uksul, Jamil Rzaev, Evgeniy Galushko, Ekaterina Gormolysova, Anatoliy Bervitskiy, Henry Schroeder, Márton Eördögh, Marco Losa, Pietro Mortini, Rüdiger Gerlach, Mohammed Azab, Karol Budohoski, Robert Rennert, Michael Karsy, William Couldwell, Apio Antunes, Jörg Flitsch, and Franz Ricklefs
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Cancer Research ,Oncology ,Neurology (clinical) - Abstract
Benchmarks are important to measure and aid in improve outcomes for surgical procedures. However, best achievable results that have been validated internationally for transsphenoidal surgery are not available. Therefore, we aimed to establish robust, standardized outcome benchmarks for transsphenoidal surgery of pituitary adenomas. A total of 2862 transsphenoidal tumor resections from 12 high-volume centers in 4 continents were analyzed. Patients were risk stratified and the median values of each center’s outcomes were established. The outcome benchmark was defined as the 75th percentile of all median values for a particular outcome as defined by Staiger et al. Out of 2862 patients, 1201 (41.9%) defined the benchmark cohort. The proportion of benchmark cases contributing to the final cohort ranged across centers between 22.1% to 59.7%. Within the benchmark cases, 928 (73.3%) patients underwent microscopic (MTS) and 263 (21.9%) patients endoscopic endonasal resection (EES). The overall postoperative complication rate was 18.9% with an in-hospital mortality between 0.0-0.8%. Benchmark cutoffs were ≤ 3.3% for reoperation rate, ≤ 4.6% for cerebrospinal fluid leak requiring intervention, and ≤ 15.3% for transient diabetes insipidus. At 6 months follow-up, benchmark cutoffs were calculated as follows: readmission rate: ≤ 7.1%, new hypopituitarism ≤ 15.5%, new neurological deficit ≤ 1.2%, tumor remnant ≤ 25.5%. This analysis defines benchmark values for transsphenoidal resection of pituitary adenomas targeting morbidity, mortality, surgical and tumor-related outcomes. The benchmark cutoffs can be used to assess different centers, patients’ populations, and novel surgical techniques.
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- 2022
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20. PATH-31. METHYLATION SUBCLASS RECEPTOR TYROSINE KINASE II AS A DRIVER FOR SEIZURES IN IDH-WILDTYPE GLIOBLASTOMA
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Richard Drexler, Manfred Westphal, Franz Ricklefs, Ulrich Schüller, Lasse Dührsen, and Alicia Eckhardt
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Cancer Research ,biology ,Receptor Protein-Tyrosine Kinases ,Wild type ,Methylation ,Receptor tyrosine kinase ,Subclass ,chemistry.chemical_compound ,Oncology ,chemistry ,DNA methylation ,biology.protein ,Cancer research ,Neurology (clinical) ,Gene ,DNA - Abstract
BACKGROUND Seizures are a common symptom of patients suffering from glioblastoma and there is evidence that these tumours are morphologically different. However, the relationship of DNA methylation and glioblastoma-related seizures has not been well characterized. Only one study described an amplification of genes encoding receptor tyrosine kinases (RTK) as a positive predictor for intraoperative seizures during craniotomy. METHODS 59 patients who underwent surgery with confirmed IDH-wildtype glioblastoma, WHO grade 4, were included. Genome-wide DNA methylation profiling was performed using an 850k Illumina EPIC array and classified by the DKFZ brain tumor classifier. Methylation glioblastoma subclasses and gene alterations were correlated with clinical characteristics including preoperative and long-term seizures. RESULTS Overall, 18 of 59 patients (30.5%) presented with seizures of whom suffered 8 (44.4%) from a focal and 10 (55.6%) from a generalized seizure. Correlation of preoperative seizures with glioblastoma subclasses and DNA genes identified a higher incidence of preoperative seizures in patients with the glioblastoma subclass of receptor tyrosine kinase II (RTK; EGFR amplified) (p=0.031). In addition, these patients were more likely to present with generalized seizures (p=0.05). In multivariate analysis, temporal location (p=0.014, OR 5.785) but moreover RTK II (p=0.024, OR 7.052) was most predictive for preoperative seizures. Furthermore, recurrent seizures with an increased antiepileptic medication at last follow-up (mean: 9.2 months) occurred more often in RTK II-glioblastoma (p< 0.05). Kaplan-Meier curves showed no significant association between the presentation of seizures and overall or progression-free survival. In addition, further survival analyses did not reveal a correlation of methylation glioblastoma subgroups with the outcome. CONCLUSION Our study showed a strong correlation of the RTK II methylation subclass with preoperative and long-term seizures in patients suffering from glioblastoma.
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- 2021
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21. SURG-14. Value of the Classification of Intraoperative Adverse Events (ClassIntra) for Resection of CNS Neoplasms in Pediatric and Adolescent Patients
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Richard Drexler, Friederike Fritzsche, Franz Ricklefs, Gertrud Kammler, Thorsten Dohrmann, Rainer Nitzschke, Manfred Westphal, and Lasse Dührsen
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Cancer Research ,Oncology ,Neurology (clinical) - Abstract
OBJECTIVE: Outcome measuring is increasingly important in neurosurgery. Recently, a classification for assessing Intraoperative adverse events (iAE) was introduced (ClassIntra). We aimed to analyze the reliability of the ClassIntra to reflect Intraoperative complications and the potential to predict the outcome of pediatric and adolescent patients who underwent resection of CNS neoplasms. METHODS: A prospective study between 01 July and 31 December 2021 was conducted. The ClassIntra grade for each tumor resection was evaluated at sign-out (Grade 0 to V). Postoperative complications were graded after Clavien-Dindo and Comprehensive Complication Index (CCI). Neurological status was assessed prior surgery and at discharge using Lansky Index, NIHSS, NANO, GCS, and mRS. RESULTS: 21 pediatric and adolescent patients who underwent resection of CNS neoplasms were included. Of these, 8 (38.1%) were female with a mean (SD) age of 9.9 (5.2) years. During 13 (61.9%) resection an iAE was noted, of which 11 (52.4%) were classified as ClassIntra I and 2 (9.5%) as ClassIntra II. The majority (66.7%) underwent surgery for infratentorial pathology, whereas 4 (19.0%) had a supratentorial and 3 (14.3%) a spinal pathology. Preoperative characteristics did not correlate with the severity of ClassIntra. In patients without an iAE, a gross total resection was achieved more frequently (p=0.048). Focusing on postoperative outcome revealed a higher severity of cumulative complications as presented by the CCI (10.4 versus 40.5), longer hospital stay (p=0.04), and higher 30-day readmission rate (p
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- 2022
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22. PATH-05 Challenge and clinical relevance of a non-matching classifier output in genome-wide DNA methylation analysis for CNS neoplasms in pediatric and adolescent patients
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Richard Drexler, Alicia Eckhardt, Helena Bode, Katrin Lamszus, Manfred Westphal, Ulrich Schüller, and Malte Mohme
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Cancer Research ,Oncology ,Neurology (clinical) - Abstract
OBJECTIVE: The molecular classification of CNS tumors has revolutionized our understanding of the biological heterogeneity and diversity of tumor subtypes. DNA methylation-based classification allows to discriminate subtypes. Although DNA methylation-based classification can diagnose tumors with high specificity, there are tumors which cannot be classified. We aimed to gain further insight into these challenging cases. METHODS: Overall, 21 patients with a CNS tumor that was non-classifiable (confidence score
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- 2022
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23. The clinical relevance of the Hippo pathway in pancreatic ductal adenocarcinoma
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Moritz Kleine, Bernd Feyerabend, Karl J. Oldhafer, Richard Drexler, Kim C Wagner, Tim Reese, and Mirco Küchler
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0301 basic medicine ,Male ,Cancer Research ,MST1 ,medicine.medical_specialty ,Hippo pathway ,Cell Cycle Proteins ,Protein Serine-Threonine Kinases ,medicine.disease_cause ,Serine-Threonine Kinase 3 ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,Downregulation and upregulation ,Pancreatic cancer ,Internal medicine ,medicine ,Humans ,Hippo Signaling Pathway ,Neoplasm Metastasis ,Aged ,Hippo signaling pathway ,Hematology ,business.industry ,Nuclear Proteins ,TEA Domain Transcription Factors ,PDAC ,General Medicine ,medicine.disease ,Prognosis ,Immunohistochemistry ,DNA-Binding Proteins ,Pancreatic Neoplasms ,030104 developmental biology ,Oncology ,030220 oncology & carcinogenesis ,Cancer research ,Female ,business ,Carcinogenesis ,Original Article – Cancer Research ,Carcinoma, Pancreatic Ductal ,Signal Transduction ,Transcription Factors - Abstract
Purpose The Hippo pathway has broadened in cancer research in the past decade and revealed itself to be an important driver for tumorigenesis and metastatic spread. In this study, we investigated the clinical relevance of the Hippo pathway with regard to metastatic invasion, patients’ outcome and histopathological features. Methods Protein expression of components of the Hippo pathway were analyzed by immunohistochemistry (IHC) using paraffin-embedded tissue from 103 patients who had been diagnosed with pancreatic ductal adenocarcinoma and had undergone surgery. Results were correlated with clinicopathological data, disease-free and overall survival. Results Immunohistochemistry studies in pancreatic tumour tissues revealed a significant upregulation of MST1, MST2, pLATS, pYAP and 14-3-3, representing the active Hippo pathway, in non-metastasized patients (p p Conclusion The Hippo pathway is inactive in metastasized patients releasing the pro-metastatic and proliferative potential of the pathway. Furthermore, our study underlines the prognostic relevance of the Hippo pathway as a shift in the balance towards the inactive pathway predicts an unfavorable OS and DFS.
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- 2020
24. Involvement of Medical Students During the Coronavirus Disease 2019 Pandemic: A Cross-Sectional Survey Study
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Jan M Hambrecht, Richard Drexler, and Karl J. Oldhafer
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medicine.medical_specialty ,student ,Coronavirus disease 2019 (COVID-19) ,Cross-sectional study ,media_common.quotation_subject ,education ,030204 cardiovascular system & hematology ,medical school ,Likert scale ,03 medical and health sciences ,0302 clinical medicine ,Pandemic ,Gratitude ,medicine ,media_common ,Academic year ,Data collection ,business.industry ,volunteer work ,pandemic ,General Engineering ,Medical school ,covid ,Medical Education ,medical student ,covid-19 ,Family medicine ,Public Health ,business ,030217 neurology & neurosurgery - Abstract
Background: The coronavirus disease 2019 (COVID-19) pandemic affects the education of medical students around the world and countries have had differing responses in dealing with this dynamic situation. The role of medical students in fighting this pandemic is controversial and it is yet to be elucidated how they can best be of service. The aim of this study is to evaluate the working fields of volunteering students and the impact of the pandemic on final year students from a student's perspective. Methods: An anonymous online survey was conducted amongst 219 medical students from Hamburg (Germany), using an institutional online data collection program. Results: A total of 137 questionnaires (63.5%) were completed. Of these, 97 participants were students from academic year three to five (70.8%) and 40 students were in the final year of medical school (29.2%). Of the 97 students from academic year three to five, 68 students (70.1%) signed up for voluntary duties during the pandemic. Interestingly, only 25.0% of the students were called for voluntary work in hospitals or health authorities. Final year students had already been working in hospitals since before the outbreak, with 35.0% of them assisting doctors in the treatment of COVID-19 positive patients during their placements. Using a 5-Point Likert Scale, the students who volunteered self-assessed their work as more useful and received more gratitude than final year students (p
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- 2020
25. Establishing a student-run free clinic in a major city in Northern Europe: a 1-year experience from Hamburg, Germany
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Felix Fröschle, Tristan Scheer, Lisa Valentin, Tobias N Meyer, Jara Janzen, Klara Ustorf, Richard Drexler, Franziska Lehnert, Karl Jürgen Oldhafer, Louisa Lehner, Christopher Predel, Refmir Tadzic, and Berit Sturm
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Medical education ,medicine.medical_specialty ,Canada ,020205 medical informatics ,Free clinic ,Student Run Clinic ,medical students ,02 engineering and technology ,Ambulatory Care Facilities ,film.subject ,03 medical and health sciences ,Underserved Population ,0302 clinical medicine ,Cultural diversity ,Germany ,Health care ,0202 electrical engineering, electronic engineering, information engineering ,Medicine ,media_common.cataloged_instance ,Humans ,AcademicSubjects/MED00860 ,030212 general & internal medicine ,European union ,health services ,SRFC ,media_common ,business.industry ,Public Health, Environmental and Occupational Health ,General Medicine ,Country of origin ,Europe ,Editor's Choice ,film ,Treatment modality ,Family medicine ,business ,Perspectives ,health Care - Abstract
Background Student-Run Free Clinics (SRFCs) have been an integral part of US medical schools since the 1960s and provide health care to underserved populations. In 2018, we established an SRFC in Hamburg, Germany, a major city in Northern Europe. The aim of this study was to describe the central problems and to investigate the usefulness of an SRFC in a country with free access to medical care, such as Germany. Methods All consecutive patients treated at the SRFC Hamburg between February 2018 and March 2019 that consented to this study were analyzed regarding clinical characteristics, diagnosis, readmission rate and country of origin. Results Between February 2018 and March 2019, 229 patients were treated at the SRFC in Hamburg. The patients came from 33 different countries with a majority (n = 206, 90%) from countries inside the European Union. The most common reasons for visiting the SRFC were infections (23.2%), acute or chronic wounds (13.5%) and fractures (6.3%). Conclusion Our multicultural patients suffer mainly from infections and traumatological and dermatological diseases. We find similarities to published Canadian SRFC patient cohorts but differences in diseases and treatment modalities compared to US SRFCs. Importantly, we demonstrate the relevance and necessity of the SRFC in a major city in Northern Europe.
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- 2019
26. Resection of pancreatic ductal adenocarcinoma with major vascular reconstruction: a single centre experience
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Kim C Wagner, Richard Drexler, Tim Reese, and Karl J. Oldhafer
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Single centre ,medicine.medical_specialty ,Pancreatic ductal adenocarcinoma ,Hepatology ,business.industry ,Vascular reconstruction ,Gastroenterology ,medicine ,Radiology ,business ,Resection - Published
- 2020
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27. The potential role of heat shock protein 27 as a prognostic marker in pancreatic ductal adenocarcinoma
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Karl J. Oldhafer, Richard Drexler, Kim C Wagner, and M. Küchler
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Pancreatic ductal adenocarcinoma ,Hepatology ,business.industry ,Heat shock protein ,Gastroenterology ,Cancer research ,Medicine ,business - Published
- 2020
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28. HSP27 regulates the Hippo pathway and thereby promotes metastasis in pancreatic ductal adenocarcinoma
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Richard Drexler, Kim C. Wagner, Mirco Küchler, and Karl-Jürgen Oldhafer
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Hepatology ,Endocrinology, Diabetes and Metabolism ,Gastroenterology - Published
- 2019
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29. Setting Benchmarks for Microsurgical Clipping of Unruptured Intracranial Aneurysms
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Richard Drexler, Principal Investigator
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- 2022
30. The Implementation of the Classification of Intraoperative Adverse Events (ClassIntra) for Neurosurgical Procedures
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Richard Drexler, Principal Investigator
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- 2021
31. Setting Benchmarks for Transsphenoidal Resection of Pituitary Adenomas
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Brigham and Women's Hospital and Richard Drexler, Principal Investigator
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- 2021
32. EASINESS-TRIAL - Enhancing Safety in Epilepsy Surgery
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Charite University, Berlin, Germany, University of Erlangen-Nürnberg, University Clinic Frankfurt, Vienna General Hospital, and Richard Drexler, Resident
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- 2021
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