20 results on '"Mathier, E."'
Search Results
2. Theory of rotation and torsion spectra for a semi-rigid model of molecules with an internal rotor of C 2v symmetry.
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Bauder, A., Mathier, E., Meyer, R., Ribeaud, M., and Günthard, Hs.H.
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- 1968
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Catalog
3. Theory of rotation and torsion spectra for a semi-rigid model of molecules with an internal rotor of C2v symmetry
- Author
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Bauder, A., Mathier, E., Meyer, R., Ribeaud, M., and Günthard, Hs.H.
- Abstract
The theory of the rotation-internal rotation spectra for a rather general class of molecules with an internal rotor of the symmetry C2v is developed in the semi-rigid model approximation. Analytical expressions for the classical and quantum-mechanical hamiltonian are given. It is shown that the energy matrix may be analytically calculated in an appropriate zeroth-order basis composed of rotational and trigonometric wave functions. Symmetry properties of the hamiltonian are given and used extensively in factoring the energy matrix. The irreducible blocks of this matrix are of infinite order. The asymptotic behaviour of the matrix elements far from the diagnoal is shown to be O(ηn) (η < 1; n is the distance from the main diagonal), which is of decisive importance in the numerical diagonalization of such matrices.A few numerical examples for a model are given in order to demonstrate the high precision achievable in the infinite matrix diagonalization. Furthermore the internal rotation problem (J = 0 states) is discussed, including the application to actual barrier determination from far infra-red spectra or microwave spectra as well as a comparison with the symmetric internal rotor case. Finally selection rules for electric dipole transitions and analytical expressions for the line strengths are given. It is shown that the theory can be developed to the same degree of explicitness as in the case of the rigid asymmetric rotor. more...
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- 1968
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4. Analysis of microwave and infrared transitions of phenol by rotation-internal rotation theory
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Mathier, E., primary, Welti, D., additional, Bauder, A., additional, and Günthard, Hs.H., additional
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- 1971
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5. ChemInform Abstract: ANALYSIS OF MICROWAVE AND INFRARED TRANSITIONS OF PHENOL BY ROTATION-INTERNAL ROTATION THEORY, PHENOL-OD
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LARSEN, N. WESSEL, primary, MATHIER, E., additional, BAUDER, A., additional, and GUENTHARD, HS. H., additional
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- 1973
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6. Numerical solution of the eigenvalue problem of infinite matrices in molecular dynamics
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Mathier, E., primary, Attanasio, A., additional, Keller, J., additional, Nösberger, P., additional, Bauder, A., additional, and Günthard, Hs.H., additional
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- 1972
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7. Analysis of microwave and infrared transitions of phenol by rotation-internal rotation theory. Phenol-OD
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Larsen, N.Wessel, primary, Mathier, E., additional, Bauder, A., additional, and Günthard, Hs.H., additional
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- 1973
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8. Focal brachytherapy as definitive treatment for localized prostate cancer: A systematic review and meta-analysis.
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Mohamad O, Nicosia L, Mathier E, Riggenbach E, Zamboglou C, Aebersold DM, Alongi F, and Shelan M
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- Aged, Humans, Male, Disease-Free Survival, Neoplasm Grading, Neoplasm Recurrence, Local radiotherapy, Prostate-Specific Antigen blood, Treatment Outcome, Middle Aged, Brachytherapy adverse effects, Brachytherapy methods, Prostatic Neoplasms blood, Prostatic Neoplasms mortality, Prostatic Neoplasms pathology, Prostatic Neoplasms radiotherapy
- Abstract
Purpose: In this systematic review and meta-analysis, we describe the oncologic and toxicity outcomes of definitive focal brachytherapy for prostate cancer., Methods and Materials: A PROSPERO registered study (CRD42023410170) was conducted following the Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) guidelines. PubMed, Embase, and The Cochrane Library were searched for studies between 2000 and 2022. Two authors independently performed the initial search. Biochemical recurrence-free survival (bRFS) was defined as the primary endpoint for the meta-analysis. Generalized linear mixed-effects models were conducted to calculate effect size and quantify heterogeneity. We also describe the side effects and local recurrence patterns of focal brachytherapy., Results: Ten studies were identified and included 315 patients treated using focal brachytherapy as a definitive treatment. Mean (SD) age was 67.65 (7.9) years and mean (SD) PSA was 7.15 (2.7) ng/mL. Most patients (n = 236, 75%) underwent LDR Brachytherapy and 25% received HDR brachytherapy. Among the participants, 147 (46.5%) had a Gleason score ≤6, and 169 (53.5%) had a Gleason score ≥7. Only 11 (3.5%) patients received ADT. Overall, bRFS rate at median follow-up 4 years (Range: 1-6.42 years) was 91% (95% confidence interval [CI], 82-95%). Acute Grade ≤ 2 GU and GI toxicities were reported in 22 (7%) and 11 (3.5%) patients, respectively. Late Grade ≤ 2 GU and GI toxicity were reported in 6 (2%) and 14 (4.4%) patients, respectively. One case of prostate hemorrhage due to improper foley removal was noted but otherwise no acute or late Grade 3 or higher GI or GU toxicity related to radiotherapy was reported., Conclusion: Overall, definitive focal brachytherapy has a favorable toxicity profile. Oncologic outcomes are yet to mature. The evidence is limited by the small number of studies with low patients' number, across study heterogeneity, and possibility of publication bias., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.) more...
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- 2024
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9. HypoFocal SRT Trial: Ultra-hypofractionated focal salvage radiotherapy for isolated prostate bed recurrence after radical prostatectomy; single-arm phase II study; clinical trial protocol.
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Mathier E, Althaus A, Zwahlen D, Lustenberger J, Zamboglou C, De Bari B, Aebersold DM, Guckenberger M, Zilli T, and Shelan M
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- Male, Humans, Treatment Outcome, Androgen Antagonists therapeutic use, Positron Emission Tomography Computed Tomography methods, Prospective Studies, Quality of Life, Neoplasm Recurrence, Local pathology, Prostatectomy, Salvage Therapy methods, Prostate-Specific Antigen, Multicenter Studies as Topic, Clinical Trials, Phase II as Topic, Prostate diagnostic imaging, Prostate surgery, Prostate pathology, Prostatic Neoplasms diagnostic imaging, Prostatic Neoplasms radiotherapy, Prostatic Neoplasms surgery
- Abstract
Introduction: Despite radical prostatectomy (RP) and radiotherapy (RT) being established treatments for localised prostate cancer, a significant number of patients experience recurrent disease. While conventionally fractionated RT is still being used as a standard treatment in the postoperative setting, ultra-hypofractionated RT has emerged as a viable option with encouraging results in patients with localised disease in the primary setting. In addition, recent technological advancements in RT delivery and precise definition of isolated macroscopic recurrence within the prostate bed using prostate-specific membrane antigen-positron emission tomography (PSMA-PET) and multiparametric MRI (mpMRI) allow the exploration of ultra-hypofractionated schedules in the salvage setting using five fractions., Methods and Analysis: In this single-arm prospective phase II multicentre trial, 36 patients with node-negative prostate adenocarcinoma treated with RP at least 6 months before trial registration, tumour stage pT2a-3b, R0-1, pN0 or cN0 according to the UICC TNM 2009 and evidence of measurable local recurrence within the prostate bed detected by PSMA PET/CT and mpMRI within the last 3 months, will be included. The patients will undergo focal ultra-hypofractionated salvage RT with 34 Gy in five fractions every other day to the site of local recurrence in combination with 6 months of androgen deprivation therapy. The primary outcome of this study is biochemical relapse-free survival at 2 years. Secondary outcomes include acute side effects (until 90 days after the end of RT) of grade 3 or higher based on Common Terminology Criteria for Adverse Events V.5, progression-free survival, metastasis-free survival, late side effects and the quality of life (based on European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-C30, QLQ-PR25)., Ethics and Dissemination: The study has received ethical approval from the Ethics Commission of the Canton of Bern (KEK-BE 2022-01026). Academic dissemination will occur through publications and conference presentations., Trial Registration Number: NCT05746806., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.) more...
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- 2024
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10. Five Fractions versus Seven Fractions SBRT for Intermediate- and High-Risk Prostate Cancer: A Propensity Score Matched Pair Analysis.
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Schröder C, Mose L, Mathier E, Zwahlen DR, Aebersold DM, Förster R, and Shelan M
- Abstract
Purpose: To compare two stereotactic body radiotherapy (SBRT) regimens in patients with intermediate- or high-risk prostate cancer with regards toxicity and efficacy., Methods/material: We retrospectively collected data from 198 patients treated with SBRT for prostate cancer at two different institutions. Patients received either 35-36.25 Gy in five fractions (group A) using Cyberknife robotic platform or 42.7 Gy in seven fractions (group B) using a C-arm LINAC (image-guided). Propensity score matching was done (2:1 nearest neighbor matching without replacement), resulting in 120 patients (80 patients for group A, 40 patients for group B). Toxicity, PSA nadir, biochemical failure and disease-free survival (DFS) were analyzed., Results: Median follow up of all patients was 13 months (range 1-91 months). Overall, 23.3% of patients had ≥G2 acute GU toxicity (21.1% group A versus 30% group B ( p = 0.222)) and 6.6% of patients ≥G2 GI toxicity (2.5% versus 15% ( p = 0.010)). There was one acute G3 GU toxicity in arm A and one acute G4 rectal bleeding in group B (anticoagulated patient). Regarding late toxicity, 14.1% of patients had ≥G2 late GU toxicity (17.4% versus 6.6% ( p = 0.159)) and 5.0% of patients had ≥G2 late GI toxicity (1.4% versus 13.3% ( p = 0.013)). There was one G3 late GU toxicity in arm B and two G3 late GI toxicities, one in each arm. Relative median PSA reduction was 92.4% (-53.9-99.9%) from baseline PSA (93.7% (-53.9-99.9%) in group A versus 87.7% (39.8-99.9%) in group B ( p = 0.043). In total, 4.2% of patients had biochemical relapse, 5.0% in group A and 2.5% in group B ( p = 0.518). One-year DFS in the overall cohort was 97.3%, 98.8% in group A and 94.3% in group B ( p = 0.318)., Conclusion: Both SBRT regimens have acceptable acute and late toxicity and good efficacy. There are significantly more GI toxicities in the seven-fraction regimen. Longer follow-up is warranted for better comparison of long-term efficacy. more...
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- 2023
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11. [Multimodality treatment in high-risk and very high-risk prostate cancer: outcomes from international phase III randomized controlled trials].
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Mathier E, Heusel A, and Shelan M
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- Combined Modality Therapy, Humans, Male, Prostatic Neoplasms therapy
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- 2022
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12. Adherence to Contouring and Treatment Planning Requirements Within a Multicentric Trial: Results of the Quality Assurance of the SAKK 09/10 trial.
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Beck M, Sassowsky M, Schär S, Mathier E, Halter M, Zwahlen DR, Hölscher T, Arnold W, Polat B, Hildebrandt G, Müller AC, Putora PM, Papachristofilou A, Hayoz S, Schär C, Li Q, Sumila M, Zaugg K, Guckenberger M, Ost P, Bosetti DG, Reuter C, Gomez S, Khanfir K, Aebersold DM, Ghadjar P, and Pra AD more...
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- Humans, Male, Prostatectomy, Rectum, Salvage Therapy methods, Gastrointestinal Diseases etiology, Prostatic Neoplasms diagnostic imaging, Prostatic Neoplasms radiotherapy, Radiotherapy, Intensity-Modulated methods
- Abstract
Purpose: To evaluate the results of the radiation therapy (RT) quality assurance (QA) program of the phase 3 randomized SAKK 09/10 trial in patients with biochemically recurrent prostate cancer after prostatectomy., Methods and Materials: Within the Schweizerische Arbeitsgemeinschaft für Klinische Krebsforschung (SAKK) 09/10 trial testing 64-Gy versus 70-Gy salvage RT, a central collection of treatment plans was performed and thoroughly reviewed by a dedicated medical physicist and radiation oncologist. Adherence to the treatment protocol and specifically to the European Organization for the Research and Treatment of Cancer (EORTC) guidelines for target volume definition (classified as deviation observed yes vs no) and its potential correlation with acute and late toxicity (Common Terminology Criteria for Adverse Events version 4.0) and freedom from biochemical progression (FFBP) were investigated., Results: The treatment plans for 344 patients treated between February 2011 and April 2014 depicted important deviations from the EORTC guidelines and the recommendations per trial protocol. For example, in up to half of the cases, the delineated structures deviated from the protocol (eg, prostate bed in 48.8%, rectal wall [RW] in 41%). In addition, variations in clinical target volume (CTV) and planning target volume (PTV) occurred frequently (eg, CTV and PTV deviations in up to 42.4% and 25.9%, respectively). The detected deviations showed a significant association with a lower risk of grade ≥2 gastrointestinal acute toxicity when the CTV did not overlap the RW versus when the CTV overlapped the RW (odds ratio [OR], 0.43; 95% confidence interval [CI], 0.22-0.85; P = .014), and a higher rate of grade ≥2 late genitourinary (GU) toxicity when the CTV overlapped the RW (OR, 2.58; 95% CI, 1.17-5.72; P = .019). A marginally significant lower risk of grade ≥2 late GU toxicity was observed when the prostate bed did not overlap versus did overlap the RW (OR, 0.51; 95% CI, 0.25-1.03; P = .06). In addition, a marginally significant decrease in FFBP was observed in patients with PTV not including surgical clips as potential markers of the limits of the prostate bed (hazard ratio, 1.44; 95% CI, 0.96-2.17; P = .07)., Conclusions: Despite a thorough QA program, the central review of a phase 3 trial showed limited adherence to treatment protocol recommendations, which was associated with a higher risk of toxicity by means of acute or late gastrointestinal or GU toxicity and showed a trend toward worse FFBP. Data from this QA review might help to refine future QA programs and prostate bed delineation guidelines., (Copyright © 2022 Elsevier Inc. All rights reserved.) more...
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- 2022
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13. [Single dose of 24 Gy or 3-fraction SBRT regimen in the treatment of oligometastatic cancer? : A phase III multi-center trial].
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Hemmatazad H, Mathier E, Aebersold DM, and Shelan M
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- Humans, Treatment Outcome, Neoplasms, Radiosurgery
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- 2021
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14. Impact of pretreatment second look 18 FDG-PET/CT on stage and treatment changes in head and neck cancer.
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Elicin O, Vollnberg B, Shelan M, Riggenbach E, Bojaxhiu B, Mathier E, Giger R, Aebersold DM, and Klaeser B
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Background: Patients diagnosed with locoregionally advanced head and neck squamous cell carcinoma (LAHNSCC) regularly undergo staging with
18 F-FDG PET/CT in our center. In cases of delays in radiotherapy (RT) planning CT more than 4 weeks after initial PET/CT or clinically suspected progress, PET/CT is repeated for restaging and as an RT planning reference. Our aim was to determine the impact of second-look PET/CT on stage migration, treatment change and RT planning., Methods: Consequent treatment changes were categorized as minor and major. Minor changes were defined as PET/CT-based modifications of RT plans, e.g., the addition of anatomical compartments, changes in high- and low-risk dose levels or both. Major changes included changes from curative to palliative treatment intent and alterations of interdisciplinary treatment plans, such as the addition of induction chemotherapy, switch to primary surgery, no treatment and/or the necessity of additional diagnostic work-up resulting in the postponement or cancellation of treatment., Results: Thirty-two newly diagnosed LAHNSCC patients who were treated between 2014 and 2018 underwent second-look PET/CT (median interval 42.5 days). Second-look PET/CT led to locoregional and distant upstaging in 3/32 and 1/32 patients, respectively. In 1/32 patients (3%), second-look PET/CT led to a palliative approach with systemic treatment. New lymph node metastases were discovered in 16 patients, 6 of whom also showed significant progression of the primary tumor, resulting in minor changes in 16 of the remaining 31 patients (52%) who were treated curatively., Conclusion: If RT treatment planning of LAHNSCC was delayed by more than 4 weeks after initial PET/CT staging or when progression was clinically suspected, a second look at18 FDG-PET/CT was performed. This led to changes in treatment planning in more than half of the cases, which is expected to directly influence oncologic outcomes., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Author(s).) more...- Published
- 2021
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15. The impact of delivery daytime and seasonality of radiotherapy for head and neck cancer on toxicity burden.
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Brolese EK, Cihoric N, Bojaxhiu B, Sermaxhaj B, Schanne DH, Mathier E, Lippmann J, Shelan M, Eller Y, Aebersold DM, Giger R, and Elicin O
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- Humans, Radiotherapy Dosage, Retrospective Studies, Squamous Cell Carcinoma of Head and Neck, Carcinoma, Squamous Cell radiotherapy, Head and Neck Neoplasms radiotherapy
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Aim: The potential impact of the daytime and season of radiotherapy application on acute and late toxicity burden was analyzed on a cohort of curatively treated head and neck squamous cell carcinoma patients., Methods: Through a retrospective chart review, patient and tumor characteristics, treatment parameters and outcome were obtained. Patients treated with definitive or adjuvant radiotherapy with and without chemotherapy receiving ≥60 Gy between 2002 and 2015 were included (n = 617). Daily fraction times and dates were extracted. Median radiotherapy delivery time of each patient was categorized as morning (AM) and afternoon (PM). Treatment season was defined by the median day of the treatment course. Each year was divided into DARK and LIGHT by the March and September equinoxes. Acute (T) and late (A) toxicity were defined by TAME methodology., Results: Median follow-up was 51 months. Mean T and A scores during and after radiotherapy in DARK vs. LIGHT were 1.98 vs. 1.61 (p = 0.0127) and 0.41 vs. 0.30 (p = 0.1699), respectively. Mean T and A scores during and after AM vs. PM radiotherapy were 1.71 vs. 1.88 (p = 0.0387) and 0.31 vs. 0.41 (p = 0.2638), respectively. Multivariate analyses indicated DARK vs. LIGHT as the only independent treatment time-related factor among other factors such as tumor subsite, UICC stage, radiotherapy technique, and chemotherapy for T., Conclusion: This is the first study investigating the impact of seasonality on toxicity burden, showing higher acute toxicity with radiotherapy in DARK. The daytime did not predict the toxicity. The hypothesis-generating findings of this retrospective study should be further investigated., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.) more...
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- 2021
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16. The prognostic impact of daytime and seasonality of radiotherapy on head and neck cancer.
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Elicin O, Koller Brolese E, Bojaxhiu B, Sermaxhaj B, Schanne DH, Mathier E, Lippmann J, Shelan M, Eller Y, Aebersold DM, Giger R, and Cihoric N
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- Humans, Prognosis, Retrospective Studies, Squamous Cell Carcinoma of Head and Neck radiotherapy, Carcinoma, Squamous Cell radiotherapy, Head and Neck Neoplasms radiotherapy
- Abstract
Background: The potential impact of daytime and season of radiotherapy application on prognosis is unclear. This was analyzed in a retrospective cohort of patients who were diagnosed with non-metastatic head and neck squamous cell carcinoma (HNSCC) and treated with definitive radiotherapy with or without chemotherapy., Materials and Methods: Patient and tumor characteristics, treatment parameters and outcome until last follow-up or death were obtained. Median radiotherapy delivery daytime of each patient was categorized as morning (AM) and afternoon (PM). Treatment season was defined by median date of treatment course. Each year was divided into DARK and LIGHT according to equinoxes. Time-to-event endpoints were defined by first biopsy confirming the HNSCC., Results: Six hundred fifty-five cases were identified who were treated with (chemo)radiotherapy between 2002 and 2015. Median follow-up was 47 months. No significant heterogeneity in patient, tumor and treatment characteristics were observed between DARK and LIGHT or regarding median daily fraction time (X2 p > 0.05). Five-year loco-regional control (73% vs. 61%; p = 0.0108) and progression-free survival (51% vs. 43%; p = 0.0374) were superior when radiotherapy was administered in DARK. Neither the daytime nor any other treatment time-related parameter affected prognosis., Conclusion: This is the first study investigating and presenting the prognostic impact of seasonality regarding the treatment course on loco-regional control and progression-free survival (DARK > LIGHT). The biological mechanism of action is unclear. These results should be interpreted with caution and our findings have to be validated externally., Competing Interests: Conflict of interest The authors declare the absence of any conflict of interest., (Copyright © 2021 Elsevier B.V. All rights reserved.) more...
- Published
- 2021
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17. Iatrogenic Vessel Dissection in Endovascular Treatment of Acute Ischemic Stroke.
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Goeggel Simonetti B, Hulliger J, Mathier E, Jung S, Fischer U, Sarikaya H, Slotboom J, Schroth G, Mordasini P, Gralla J, and Arnold M
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- Adult, Aged, Basilar Artery diagnostic imaging, Carotid Artery Injuries therapy, Computed Tomography Angiography, Endovascular Procedures adverse effects, Female, Fibrinolytic Agents adverse effects, Humans, Iatrogenic Disease, Male, Middle Aged, Prospective Studies, Stents, Thrombectomy adverse effects, Thrombolytic Therapy adverse effects, Urokinase-Type Plasminogen Activator therapeutic use, Vertebral Artery Dissection therapy, Vertebrobasilar Insufficiency diagnostic imaging, Vertebrobasilar Insufficiency etiology, Angiography, Digital Subtraction, Basilar Artery injuries, Carotid Artery Injuries diagnostic imaging, Stroke therapy, Vertebral Artery Dissection diagnostic imaging
- Abstract
Purpose: Knowledge about the localization and outcome of iatrogenic dissection (ID) during endovascular treatment of acute ischemic stroke (AIS) is limited. We aimed to determine the frequency, clinical aspects and morphology of ID in endovascular AIS treatment and to identify predictors of this complication., Methods: Digital subtraction angiography (DSA) of ID carried out during endovascular treatment between January 2000 and March 2012 have been re-evaluated. The ID localization and morphology were analyzed and related to the interventional techniques. Baseline clinical and radiological findings, treatment modality and outcome were compared with patients without ID., Results: Out of 866 patients 18 (2%) suffered an ID (44% female, median age 64 years). Localization was extracranial in 15 (83%, 14 internal carotid artery and 1 vertebral artery) and intracranial in 3 (17%; 1 vertebrobasilar dissection and 2 in the anterior circulation). Of the IDs 5 (28%) resulted in a high-degree, 3 (17%) in a moderate, 5 (28%) in a mild and 5 (28%) in no stenosis and 8 IDs were stented in the acute phase. At 3 months 7 (42%) patients had a favorable outcome (modified Rankin score mRS ≤ 2) and 6 (33%) patients had died. Patients with ID had a different stroke etiology (p = 0.041), were more likely to be smokers (44% versus 19%, p = 0.015) and were more likely to be treated with mechanical thrombectomy (100% versus 60%, p < 0.001). Although two ID patients had relevant complications, the outcome did not differ between the groups., Conclusion: The occurrence of ID is a rare complication of endovascular AIS treatment associated with smoking and mechanical thrombectomy. more...
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- 2019
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18. Primary tumor volume delineation in head and neck cancer: missing the tip of the iceberg?
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Elicin O, Terribilini D, Shelan M, Volken W, Mathier E, Dal Pra A, Aebersold DM, Fix MK, and Manser P
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- Aged, Female, Humans, Male, Middle Aged, Tomography, X-Ray Computed, Tumor Burden, Head and Neck Neoplasms diagnostic imaging, Head and Neck Neoplasms radiotherapy, Radiotherapy Planning, Computer-Assisted methods
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Background: The aim was to evaluate the geometric and corresponding dosimetric differences between two delineation strategies for head and neck tumors neighboring air cavities., Methods: Primary gross and clinical tumor volumes (GTV and CTV) of 14 patients with oropharynx or larynx tumors were contoured using a soft tissue window (S). In a second strategy, the same volumes were contoured with an extension to include the parts which became visible on lung window (L). For the calculation of Hausdorff-distances (HD) between contoured volumes of the two strategies, triangular meshes were exported. Two radiotherapy plans with identical goals and optimization parameters were generated for each case. Plan_S were optimized on CTV_S, and Plan_L on CTV_L. The dose coverages of CTV_L and CTV_Δ (CTV_L minus CTV_S) were evaluated in Plan_S. OAR doses were compared among Plan_S and Plan_L., Results: Median three-dimensional HD for GTVs and CTVs were 5.7 (±2.6) and 9.3 (±2.8) mm, respectively. The median volume differences between structures contoured using L and S windows were 9% (±5%) and 9% (±4%) for GTV and CTV, respectively. In 13 out of 14 cases, Plan_S met the plan acceptance criteria for CTV_L. In 8 cases CTV_Δ was covered insufficiently in Plan_S. Mean and median differences in OAR dose-volume histogram parameters between Plan_S and Plan_L were within 3%., Conclusion: For the current practice in radiotherapy planning for head and neck cancer, the delineation of L-based volumes seems unnecessary. However, in special settings, where smaller or no PTV margins are used, this approach may play an important role for local control. more...
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- 2017
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19. Current status and perspectives of interventional clinical trials for glioblastoma - analysis of ClinicalTrials.gov.
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Cihoric N, Tsikkinis A, Minniti G, Lagerwaard FJ, Herrlinger U, Mathier E, Soldatovic I, Jeremic B, Ghadjar P, Elicin O, Lössl K, Aebersold DM, Belka C, Herrmann E, and Niyazi M
- Subjects
- Humans, Research Design, Clinical Trials as Topic methods, Glioblastoma therapy
- Abstract
The records of 208.777 (100%) clinical trials registered at ClinicalTrials.gov were downloaded on the 19th of February 2016. Phase II and III trials including patients with glioblastoma were selected for further classification and analysis. Based on the disease settings, trials were classified into three groups: newly diagnosed glioblastoma, recurrent disease and trials with no differentiation according to disease setting. Furthermore, we categorized trials according to the experimental interventions, the primary sponsor, the source of financial support and trial design elements. Trends were evaluated using the autoregressive integrated moving average model. Two hundred sixteen (0.1%) trials were selected for further analysis. Academic centers (investigator initiated trials) were recorded as primary sponsors in 56.9% of trials, followed by industry 25.9%. Industry was the leading source of monetary support for the selected trials in 44.4%, followed by 25% of trials with primarily academic financial support. The number of newly initiated trials between 2005 and 2015 shows a positive trend, mainly through an increase in phase II trials, whereas phase III trials show a negative trend. The vast majority of trials evaluate forms of different systemic treatments (91.2%). In total, one hundred different molecular entities or biologicals were identified. Of those, 60% were involving drugs specifically designed for central nervous system malignancies. Trials that specifically address radiotherapy, surgery, imaging and other therapeutic or diagnostic methods appear to be rare. Current research in glioblastoma is mainly driven or sponsored by industry, academic medical oncologists and neuro-oncologists, with the majority of trials evaluating forms of systemic therapies. Few trials reach phase III. Imaging, radiation therapy and surgical procedures are underrepresented in current trials portfolios. Optimization in research portfolio for glioblastoma is needed. more...
- Published
- 2017
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20. Dynamic changes of intramural hematoma in patients with acute spontaneous internal carotid artery dissection.
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Heldner MR, Nedelcheva M, Yan X, Slotboom J, Mathier E, Hulliger J, Verma RK, Sturzenegger M, Jung S, Bernasconi C, Arnold M, Wiest R, and Fischer U
- Subjects
- Brain Ischemia pathology, Brain Ischemia physiopathology, Carotid Artery, Internal, Dissection physiopathology, Carotid Stenosis pathology, Carotid Stenosis physiopathology, Cerebral Angiography, Databases, Factual, Disease Progression, Female, Follow-Up Studies, Hematoma physiopathology, Humans, Magnetic Resonance Angiography, Male, Middle Aged, Prospective Studies, Stroke pathology, Stroke physiopathology, Carotid Artery, Internal, Dissection pathology, Hematoma pathology
- Abstract
Background: We prospectively investigated temporal and spatial evolution of intramural hematomas in patients with acute spontaneous internal carotid artery dissection using repeated magnetic resonance imaging over six-months., Aim: The aim of the present study was to assess dynamic changes of intramural hematoma in patients with acute spontaneous internal carotid artery dissection at multiple follow-up time-points with T1w, PD/T2w, and magnetic resonance angiography., Methods: We performed serial multiparametric magnetic resonance imaging in 10 patients with spontaneous internal carotid artery dissection on admission, at days 1, 3, 7-14 and at months 1·5, 3, and 6. We calculated the volume and extension of the hyperintense intramural hematoma using T1w and PD/T2w fat suppressed sequences and assessed the degree of stenosis due to the hematoma using magnetic resonance angiography., Results: Mean interval from symptom onset to first magnetic resonance imaging was two-days (SD 2·7). Two patients presented with ischemic stroke, three with transient ischemic attacks, and five with pain and local symptoms only. Nine patients had a transient increase of the intramural hematoma volume, mainly up to day 10 after symptom onset. Fifty percent had a transient increase in the degree of the internal carotid artery stenosis on MRA, one resulting in a temporary occlusion. Lesions older than one-week were predominantly characterized by a shift from iso- to hyperintese signal on T2w images. At three-month follow-up, intramural hematoma was no longer detectable in 80% of patients and had completely resolved in all patients after six-months., Conclusions: Spatial and temporal dynamics of intramural hematomas after spontaneous internal carotid artery dissection showed an early volume increase with concomitant progression of the internal carotid artery stenosis in 5 of 10 patients. Although spontaneous internal carotid artery dissection overall carries a good prognosis with spontaneous hematoma resorption in all our patients, early follow-up imaging may be considered, especially in case of new clinical symptoms., (© 2015 World Stroke Organization.) more...
- Published
- 2015
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