101 results on '"Klement RJ"'
Search Results
2. Modeling the effects of ketogenic therapy on survival in patients with high grade glioma using Bayesian evidence synthesis
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Klement, RJ, additional, Bandyopadhyay, PS, additional, Champ, CE, additional, and Walach, H, additional
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- 2018
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3. Anti-tumor effects of ketogenic diets in mice: A meta-analysis
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Klement, RJ, Champ, CE, Otto, C, Kämmerer, U, Klement, RJ, Champ, CE, Otto, C, and Kämmerer, U
- Abstract
Background: Currently ketogenic diets (KDs) are hyped as an anti-tumor intervention aimed at exploiting the metabolic abnormalities of cancer cells. However, while data in humans is sparse, translation of murine tumor models to the clinic is further hampered by small sample sizes, heterogeneous settings and mixed results concerning tumor growth retardation. The aim was therefore to synthesize the evidence for a growth inhibiting effect of KDs when used as a monotherapy in mice. Methods: We conducted a Bayesian random effects meta-analysis on all studies assessing the survival (defined as the time to reach a pre-defined endpoint such as tumor volume) of mice on an unrestricted KD compared to a high carbohydrate standard diet (SD). For 12 studies meeting the inclusion criteria either a mean survival time ratio (MR) or hazard ratio (HR) between the KD and SD groups could be obtained. The posterior estimates for the MR and HR averaged over four priors on the between-study heterogeneity τ2 were MR = 0.85 (95% highest posterior density interval (HPDI) = [0.73, 0.97]) and HR = 0.55 (95% HPDI = [0.26, 0.87]), indicating a significant overall benefit of the KD in terms of prolonged mean survival times and reduced hazard rate. All studies that used a brain tumor model also chose a late starting point for the KD (at least one day after tumor initiation) which accounted for 26% of the heterogeneity. In this subgroup the KD was less effective (MR = 0.89, 95% HPDI = [0.76, 1.04]). Conclusions: There was an overall tumor growth delaying effect of unrestricted KDs in mice. Future experiments should aim at differentiating the effects of KD timing versus tumor location, since external evidence is currently consistent with an influence of both of these factors.
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- 2016
4. Clinical research framework proposal for ketogenic metabolic therapy in glioblastoma.
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Duraj T, Kalamian M, Zuccoli G, Maroon JC, D'Agostino DP, Scheck AC, Poff A, Winter SF, Hu J, Klement RJ, Hickson A, Lee DC, Cooper I, Kofler B, Schwartz KA, Phillips MCL, Champ CE, Zupec-Kania B, Tan-Shalaby J, Serfaty FM, Omene E, Arismendi-Morillo G, Kiebish M, Cheng R, El-Sakka AM, Pflueger A, Mathews EH, Worden D, Shi H, Cincione RI, Spinosa JP, Slocum AK, Iyikesici MS, Yanagisawa A, Pilkington GJ, Chaffee A, Abdel-Hadi W, Elsamman AK, Klein P, Hagihara K, Clemens Z, Yu GW, Evangeliou AE, Nathan JK, Smith K, Fortin D, Dietrich J, Mukherjee P, and Seyfried TN
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- Humans, Brain Neoplasms diet therapy, Brain Neoplasms metabolism, Brain Neoplasms drug therapy, Glutamine metabolism, Glucose metabolism, Energy Metabolism physiology, Glycolysis, Biomedical Research methods, Glioblastoma diet therapy, Glioblastoma metabolism, Glioblastoma drug therapy, Diet, Ketogenic methods
- Abstract
Glioblastoma (GBM) is the most aggressive primary brain tumor in adults, with a universally lethal prognosis despite maximal standard therapies. Here, we present a consensus treatment protocol based on the metabolic requirements of GBM cells for the two major fermentable fuels: glucose and glutamine. Glucose is a source of carbon and ATP synthesis for tumor growth through glycolysis, while glutamine provides nitrogen, carbon, and ATP synthesis through glutaminolysis. As no tumor can grow without anabolic substrates or energy, the simultaneous targeting of glycolysis and glutaminolysis is expected to reduce the proliferation of most if not all GBM cells. Ketogenic metabolic therapy (KMT) leverages diet-drug combinations that inhibit glycolysis, glutaminolysis, and growth signaling while shifting energy metabolism to therapeutic ketosis. The glucose-ketone index (GKI) is a standardized biomarker for assessing biological compliance, ideally via real-time monitoring. KMT aims to increase substrate competition and normalize the tumor microenvironment through GKI-adjusted ketogenic diets, calorie restriction, and fasting, while also targeting glycolytic and glutaminolytic flux using specific metabolic inhibitors. Non-fermentable fuels, such as ketone bodies, fatty acids, or lactate, are comparatively less efficient in supporting the long-term bioenergetic and biosynthetic demands of cancer cell proliferation. The proposed strategy may be implemented as a synergistic metabolic priming baseline in GBM as well as other tumors driven by glycolysis and glutaminolysis, regardless of their residual mitochondrial function. Suggested best practices are provided to guide future KMT research in metabolic oncology, offering a shared, evidence-driven framework for observational and interventional studies., Competing Interests: Declarations. Ethics approval and consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: A.P. is an owner of Poff Medical Consulting and Communications, LLC, which performs consulting and public speaking services related to ketogenic metabolic therapy. A.P. is a scientific advisor to Pruvit Ventures, LLC, which sells exogenous ketone products. A.P. is an owner of Metabolic Health Initiative, LLC which is a medical education company in the field of metabolic health and metabolism-based therapies. A.P. is an inventor on and receives royalties from the following patent: “Targeting Cancer with Metabolic Therapy and Hyperbaric Oxygen” (Patent Number: 9801903). D.P.D. is an inventor of patents on the use of exogenous ketones, advisor for Levels Health, and co-owner of Ketone Technologies LLC, which does consulting and public speaking events. C.E.C. receives royalties from books, consulting, and lectures on nutrition and exercise, and serves on the scientific advisory board of Simply Good Foods/Atkins. M.K. is employed by Dietary Therapies LLC. The other authors declare no competing interests., (© 2024. The Author(s).)
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- 2024
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5. Dose prescription for stereotactic body radiotherapy: general and organ-specific consensus statement from the DEGRO/DGMP Working Group Stereotactic Radiotherapy and Radiosurgery.
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Brunner TB, Boda-Heggemann J, Bürgy D, Corradini S, Dieckmann UK, Gawish A, Gerum S, Gkika E, Grohmann M, Hörner-Rieber J, Kirste S, Klement RJ, Moustakis C, Nestle U, Niyazi M, Rühle A, Lang ST, Winkler P, Zurl B, Wittig-Sauerwein A, and Blanck O
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- Humans, Consensus, Europe, Neoplasms radiotherapy, Neoplasms surgery, Organs at Risk radiation effects, Review Literature as Topic, Delphi Technique, Radiosurgery methods, Radiotherapy Dosage
- Abstract
Purpose and Objective: To develop expert consensus statements on multiparametric dose prescriptions for stereotactic body radiotherapy (SBRT) aligning with ICRU report 91. These statements serve as a foundational step towards harmonizing current SBRT practices and refining dose prescription and documentation requirements for clinical trial designs., Materials and Methods: Based on the results of a literature review by the working group, a two-tier Delphi consensus process was conducted among 24 physicians and physics experts from three European countries. The degree of consensus was predefined for overarching (OA) and organ-specific (OS) statements (≥ 80%, 60-79%, < 60% for high, intermediate, and poor consensus, respectively). Post-first round statements were refined in a live discussion for the second round of the Delphi process., Results: Experts consented on a total of 14 OA and 17 OS statements regarding SBRT of primary and secondary lung, liver, pancreatic, adrenal, and kidney tumors regarding dose prescription, target coverage, and organ at risk dose limitations. Degree of consent was ≥ 80% in 79% and 41% of OA and OS statements, respectively, with higher consensus for lung compared to the upper abdomen. In round 2, the degree of consent was ≥ 80 to 100% for OA and 88% in OS statements. No consensus was reached for dose escalation to liver metastases after chemotherapy (47%) or single-fraction SBRT for kidney primaries (13%). In round 2, no statement had 60-79% consensus., Conclusion: In 29 of 31 statements a high consensus was achieved after a two-tier Delphi process and one statement (kidney) was clearly refused. The Delphi process was able to achieve a high degree of consensus for SBRT dose prescription. In summary, clear recommendations for both OA and OS could be defined. This contributes significantly to harmonization of SBRT practice and facilitates dose prescription and reporting in clinical trials investigating SBRT., (© 2024. The Author(s).)
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- 2024
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6. The optimal amino acid pattern for humans and its implications for nutrition of cancer patients.
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Klement RJ
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Competing Interests: Conflicts of Interest: The author has completed the ICMJE uniform disclosure form (available at https://tbcr.amegroups.org/article/view/10.21037/tbcr-24-25/coif). R.J.K. serves as an unpaid editorial board member of Translational Breast Cancer Research from December 2023 to November 2025. R.J.K. receives royalties from a book on cancer. R.J.K. cooperates with MITOcare GmbH & Co. KG which involves participation in webinars, lectures and the development of nutritional supplements. R.J.K. has also received honoraria from MITOcare GmbH & Co. KG for giving webinars and lectures. The author has no other conflicts of interest to declare.
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- 2024
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7. Commentary: raised c-troponin levels as a sign of myocardial injury after COVID-19 vaccination in healthy individuals are worrying.
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Klement RJ and Walach H
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Background: Recently, Buergin et al. (Eur J Heart Fail 25(10):1871-1881, 2023 doi:10.1002/ejhf.2978) thoroughly measured a frequency of 2.8% elevated high-sensitivity cardiac troponin T levels, a sign of myocardial damage, after mRNA-1273 (Moderna) booster vaccinations. In their discussion, they claim that before vaccinations were available, the incidence and extent of myocardial damage associated with COVID-19 infection would have been much higher. We here scrutinize this claim based on empirical data., Main Body: Burgin et al. have only cited papers in support of their claim which considered hospitalized COVID-19 patients. After extracting COVID-19 infection data from Germany and Switzerland and the expected frequency of elevated troponin levels after COVID-19 infection in both hospitalized and non-hospitalized individuals, we find that the extent of myocardial damage after vaccinating a considerable proportion of the general population is expected to be much higher than after natural infections., Conclusions: The claim that the extent of myocardial injury after COVID-19 infection would be higher than after vaccination is not supported by empirical evidence and therefore wrong. We conclude that cross-national systematic observational studies should be conducted that allow a more precise estimation of the risk-benefit ratio of COVID-19 mRNA vaccinations., (© 2024. The Author(s).)
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- 2024
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8. Anti-tumor effects of ketogenic diets and their synergism with other treatments in mice: Bayesian evidence synthesis of 1755 individual mouse survival data.
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Klement RJ
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- Mice, Animals, Bayes Theorem, Diet, High-Fat, Diet, Ketogenic, Neoplasms
- Abstract
Background: Ketogenic diets (KDs) are high-fat diets with putative anti-tumor effects. The aim of this study was to synthesize the evidence for the anti-tumor effects of KDs in mice, with a focus on their possible synergism with chemotherapy (CT), radiotherapy (RT), or targeted therapies (TT)., Methods: Relevant studies were retrieved from a literature search. A total of 43 articles reporting on 65 mouse experiments fulfilled the inclusion criteria, and 1755 individual mouse survival times were collated from the study authors or the publications. The restricted mean survival time ratio (RMSTR) between the KD and control groups served as the effect size. Bayesian evidence synthesis models were used to estimate pooled effect sizes and to assess the impact of putative confounders and synergism between KD and other therapies., Results: Overall, there was a significant survival-prolonging effect of KD monotherapy (RMSTR = 1.161 ± 0.040), which was confirmed in meta-regression accounting for syngeneic versus xenogeneic models, early versus late KD start and subcutaneous versus other organ growth. Combining the KD with RT or TT, but not CT, was associated with a further 30% (RT) or 21% (TT) prolongation of survival. An analysis accounting for 15 individual tumor entities showed that KDs exerted significant survival-prolonging effects in pancreatic cancer (all treatment combinations), gliomas (KD + RT and KD + TT), head and neck cancer (KD + RT), and stomach cancer (KD+RT and KD + TT)., Conclusions: This analytical study confirmed the overall anti-tumor effects of KDs in a large number of mouse experiments and provides evidence for synergistic effects with RT and TT., (© 2023 Chang Gung University. Publishing services provided by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).)
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- 2024
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9. The value of ethnographic studies for making inferences about the nature of the human Paleolithic diet: comments on Lieberman et al. (2023).
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Klement RJ
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- Humans, Diet, Paleolithic
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Competing Interests: Conflict of interest statement The author reports no conflicts of interest.
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- 2023
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10. Metabolic factors associated with the prognosis of oligometastatic patients treated with stereotactic body radiotherapy.
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Klement RJ and Sweeney RA
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- Humans, Fluorodeoxyglucose F18, Prognosis, Positron-Emission Tomography, Radiosurgery adverse effects, Radiosurgery methods, Neoplasms pathology
- Abstract
Over the past two decades, it has been established that cancer patients with oligometastases, i.e., only a few detectable metastases confined to one or a few organs, may benefit from an aggressive local treatment approach such as the application of high-precision stereotactic body radiotherapy (SBRT). Specifically, some studies have indicated that achieving long-term local tumor control of oligometastases is associated with prolonged overall survival. This motivates investigations into which factors may modify the dose-response relationship of SBRT by making metastases more or less radioresistant. One such factor relates to the uptake of the positron emission tomography tracer 2-deoxy-2-[
18 F]fluoro-D-glucose (FDG) which reflects the extent of tumor cell glycolysis or the Warburg effect, respectively. Here we review the biological mechanisms how the Warburg effect drives tumor cell radioresistance and metastasis and draw connections to clinical studies reporting associations between high FDG uptake and worse clinical outcomes after SBRT for oligometastases. We further review the evidence for distinct metabolic phenotypes of metastases preferentially seeding to specific organs and their possible translation into distinct radioresistance. Finally, evidence that obesity and hyperglycemia also affect outcomes after SBRT will be presented. While delivered dose is the main determinant of a high local tumor control probability, there might be clinical scenarios when metabolic targeting could make the difference between achieving local control or not, for example when doses have to be compromised in order to spare neighboring high-risk organs, or when tumors are expected to be highly therapy-resistant due to heavy pretreatment such as chemotherapy and/or radiotherapy., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)- Published
- 2023
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11. Brooke-Spiegler syndrome: radiotherapy as the last resort?
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Sweeney RA, Goebeler M, Flentje M, and Klement RJ
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- Female, Humans, Aged, Skin Neoplasms pathology, Neoplastic Syndromes, Hereditary pathology, Carcinoma, Adenoid Cystic pathology, Carcinoma, Adenoid Cystic surgery
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Purpose: To describe the case of successful radiotherapeutic treatment of a woman suffering from Brooke-Spiegler syndrome who had multiple disfiguring cylindromas on the entire scalp and further tumors on the trunk., Methods: After decades of treatment with conventional therapies including surgery and topically applied salicylic acid, the 73-year-old woman agreed to undergo radiotherapeutic treatment. She received 60 Gy to the scalp and 36 Gy to painful nodules in the lumbar spine region., Results: Over a follow-up period of 14 and 11 years, respectively, the scalp nodules almost completely regressed, while the lumbar nodules became painless and considerably smaller. Apart from alopecia, no late adverse effects of treatment remain., Conclusion: This case should remind us of the potential role that radiotherapy could play in treating Brooke-Spiegler syndrome. The required dose for treatment of such extensive disease is still a matter of debate due to the scarcity of radiotherapeutic experience. This case demonstrates that for scalp tumors, 30 × 2 Gy can result in long-term tumor control, while other dose prescriptions may be adequate for tumors in other locations., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)
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- 2023
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12. SEIR models in the light of Critical Realism - A critique of exaggerated claims about the effectiveness of Covid 19 vaccinations.
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Klement RJ and Walach H
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In a recent modeling study Watson et al. (Lancet Infect Dis 2022;3099:1-10) claim that Covid-19 vaccinations have helped to prevent roughly 14-20 million deaths in 2021. This conclusion is based on an epidemiological susceptible-exposed-infectious-recovered (SEIR) model trained on partially simulated data and yielding a reproduction number distribution which was then applied to a counterfactual scenario in which the efficacy of vaccinations was removed. Drawing on the meta-theory of Critical Realism, we point out several caveats of this model and caution against believing in its predictions. We argue that the absence of vaccinations would have significantly changed the causal tendencies of the system being modelled, yielding a different reproduction number than obtained from training the model on actually observed data. Furthermore, the model omits many important causal factors. Therefore this model, similar to many previous SEIR models, has oversimplified the complex interplay between biomedical, social and cultural dimensions of health and should not be used to guide public health policy. In order to predict the future in epidemic situations more accurately, continuously optimized dynamic causal models which can include the not directly tangible, yet real causal mechanisms affecting public health appear to be a promising alternative to SEIR-type models., Competing Interests: The authors declare that they have no conflicts of interest related to this publication., (© 2023 Elsevier Ltd. All rights reserved.)
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- 2023
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13. Measurement of body composition by DXA, BIA, Leg-to-leg BIA and near-infrared spectroscopy in breast cancer patients - comparison of the four methods.
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Klement RJ, Joos FT, Reuss-Borst MA, and Kämmerer U
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- Humans, Adolescent, Young Adult, Adult, Middle Aged, Aged, Female, Absorptiometry, Photon, Reproducibility of Results, Leg, Spectroscopy, Near-Infrared, Electric Impedance, Body Composition, Breast Neoplasms
- Abstract
Background & Aims: Body composition plays a crucial role in therapy adherence and the prognosis of cancer patients. The aim of this work was to compare four measurement methods for determining body composition regarding their validity, reliability and practicability in order to be able to draft a practical recommendation as to which method is most suitable as a standard measurement method in oncology., Methods: Fat mass (FM) and fat-free mass (FFM) was estimated for 100 breast cancer patients with ages of 18-70 years during a defined 20-week inpatient and outpatient rehabilitation process after primary therapy or follow-up rehabilitation. The four methods used were dual energy X-ray absorptiometry (DXA), bioelectrical impedance analysis (BIA), leg-to-leg BIA and near-infrared spectroscopy (NIRS). At baseline (t0) and after 20 weeks (t20) the agreement between the four body composition analysis methods was quantified by pairwise method comparisons using Bland-Altman bias and limits of agreement estimates, t-tests and Lin's concordance correlation coefficients (CCCs)., Results: CCCs and Bland-Altman plots indicated that DXA and BIA, DXA and NIRS as well as BIA and NIRS showed an excellent agreement concerning FM estimation at both time points (CCC>0.9). In contrast, no methods agreed with a CCC higher than 0.9 with respect to FFM estimation. However, most estimates were also significantly different between two methods, except for BIA and NIRS which yielded comparable FFM and FM estimates at both time points, albeit with large 95% limits of agreement intervals. The agreement between DXA and BIA was best in the lowest BMI tertile and worsened as BMI increased. Significant differences were also found for FFM changes measured with DXA versus BIA (mean difference -0.4 kg, p = 0.0049), DXA versus to Leg-to-leg BIA (-0.6 kg, p = 0.00073) and for FM changes measured with DXA versus Leg-to-leg BIA (0.5 kg, p = 0.0011)., Conclusions: For accurate and valid body composition estimates, Leg-to-leg BIA cannot be recommended due to its significant underestimation of FM or significant overestimation of FFM, respectively. BIA and NIRS results showed good agreement with the gold standard DXA. Therefore both measurement methods appear to be very well suitable to assess body composition of oncological patients and should be used more frequently on a routine basis to monitor the body composition of breast cancer patients., Competing Interests: Conflict of interest There are neither (direct/indirect) financial nor personal relationships as well as no academic competitions or conflicts according personal beliefs., (Copyright © 2023 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.)
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- 2023
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14. Effects of Viktor Philippi's Bioenergetic Meditation on Anxiety, Burnout, and Depression: An Analysis of Four Feasibility Studies.
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Lehnert W, Günther-Pusch J, and Klement RJ
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- Humans, Prospective Studies, Feasibility Studies, Anxiety psychology, Burnout, Psychological, Depression, Meditation
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Introduction: Anxiety, burnout, and depression cause a substantial psychological and social burden. Bioenergetic meditation (BM) was developed by Viktor Philippi as a method to strengthen psychological and physical health. This work presents the results of four feasibility studies investigating the effects of BM developed by Viktor Philippi as a support for people suffering from these psychological disorders., Materials and Methods: A total of four prospective, non-randomized feasibility studies were conducted (N1 = 185, N2 = 140, N3 = 33, N4 = 32). Studies 1 and 2 were multicentric studies with a pre-post comparison consisting of 10 BMs within 10 weeks with individual study start and end points. Studies 3 and 4 consisted of 7 BMs within 3 days with a pre-post evaluation and follow-up measurements at 6, 12, and 18 months. The Beck Anxiety Inventory (BAI), Beck Depression Inventory (BDI-II), and Hamburg Burnout Inventory (HBI) were used to measure symptoms of anxiety, depression, and burnout, respectively., Results: After 10 BMs within 10 weeks, highly reliable decreases in symptoms of depression occurred in 58-73% of cases (p < 0.005). The median BDI-II score declined significantly by 60% (p < 0.0001) after 10 weeks of BM. Symptoms of anxiety were highly reliably reduced in roughly one-third of cases after 10 weekly BMs, with the average total BAI score declining from a severe to a moderate anxiety (p < 0.0001). The HBI showed significant improvement in all subscales. Psychological symptoms also improved significantly after 7 BMs, and symptom reductions classified as highly reliable were maintained until 18-months follow-up in more than 50% of participants., Conclusion: BM results in significant and lasting improvements in clinical symptoms of anxiety, depression, and burnout. Further studies including control groups are necessary to confirm these findings and determine any BM-specific effects., (© 2022 S. Karger AG, Basel.)
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- 2023
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15. Effect of Ketogenic Diets on Cardio-Metabolic Outcomes in Cancer Patients: A Systematic Review and Meta-Analysis of Controlled Clinical Trials.
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Amanollahi A, Khazdouz M, Malekahmadi M, Klement RJ, Lee D, and Khodabakhshi A
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- Humans, Insulin-Like Growth Factor I, Quality of Life, Body Weight, Glucose, Diet, Ketogenic, Neoplasms
- Abstract
In this systematic review and meta-analysis of clinical controlled trials (CCTs) we aimed to investigate the efficacy of KDs as an adjuvant therapy on cardiometabolic outcomes in patient with cancer compared to conventional non-ketogenic diets. Only CCTs involving cancer patients that were assigned to either a KD or a standard diet control group were selected. Two reviewers independently extracted the data, and a meta-analysis was performed using a random effects model to estimate weighted mean differences (WMDs) and confidence intervals (CIs) in body composition, metabolite, lipid profile, liver and kidney function parameters and quality of life. This meta-analysis showed a significant reduction in body weight (WMD= -2.99 kg; 95% CI: -4.67, -1.31; and P < 0.001), BMI (WMD= -1.08 kg/m
2 ; 95% CI: -1.81, -0.34; P ≤ 0.002) and fat mass (WMD= -1.48 kg; 95% CI: -2.56, -0.40; and P = 0.007) by a KD. KDs significantly decreased glucose (WMD= -5.22 mg/dl; 95% CI: -9.0, -1.44; and P = 0.007), IGF-1 (WMD= -17.52 ng/ml; 95% CI: -20.24, -14.8; and P ˂0.001) and triglyceride (WMD= -24.46 mg/dl; 95% CI: -43.96, -4.95; and P = 0.014) levels. Furthermore, KDs induced ketosis by increasing β-hydroxybutyrate (WMD= 0.56 mmol/l; 95% CI: 0.37, 0.75; and P < 0.001). There were non-significant pooled effects of KDs on improving insulin, C-reactive protein and cholesterol levels and kidney and liver function. Emotional functioning was even increased significantly in the KD compared to the SD groups. In summary we found that KDs result in a greater reduction in glucose, IGF-1, triglycerides, body weight, BMI, and fat mass in cancer patients compared to traditional non-ketogenic diets and improved emotional functioning. The quality of evidence in the meta-analysis was moderate according to the Nutrigrade assessment.- Published
- 2023
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16. Impact of a ketogenic diet intervention during radiotherapy on body composition: V. Final results of the KETOCOMP study for head and neck cancer patients.
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Klement RJ and Sweeney RA
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- Humans, Body Composition physiology, Progression-Free Survival, Diet, Ketogenic methods, Head and Neck Neoplasms radiotherapy
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Purpose: Patients with head and neck cancer (HNC) are at risk of malnutrition, especially during radiochemotherapy. We aimed to study the impact of a ketogenic diet (KD) versus an unspecified standard diet (SD) on body composition and survival in HNC patients undergoing radio(chemo)therapy., Methods: As part of a controlled clinical trial, non-metastasized HNC patients were enrolled into either a KD (N = 11) or an SD (N = 21) group between May 2015 and May 2021. Body composition was measured weekly by bioimpedance analysis and analyzed using linear mixed effects models. Overall and progression-free survival was assessed during regular follow-up., Results: A total of 7 KD and 21 SD patients completed the study and were eligible for comparative analysis. Chemotherapy was significantly associated with declines in all body composition parameters, while the KD had opposing, yet nonsignificant effects. In patients receiving chemotherapy, average weekly reductions of body mass (BM) and skeletal muscle mass (SMM) were 0.9 kg and 0.31 kg in the KD group versus 1.2 kg and 0.57 kg in the SD group, respectively. Patients in the KD group receiving no chemotherapy achieved an average increase of 0.04 kg BM and 0.12 kg SMM per week. After a median follow-up of 42 months (range 6.7-78 months) there were no significant differences in progression-free or overall survival between the groups., Conclusion: The KD may partially counteract the detrimental effects of radiochemotherapy on body composition in HNC patients. This should encourage further research into KDs in frail cancer patient populations and motivate their implementation as complementary therapy for selected patients., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)
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- 2022
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17. Bioelectrical phase angle is no adequate biomarker of inflammatory status.
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Klement RJ
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- Electric Impedance, Biomarkers, Nutritional Status, Eating
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- 2022
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18. Is the Network of World Economic Forum Young Global Leaders Associated With COVID-19 Non-Pharmaceutical Intervention Severity?
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Klement RJ and Walach H
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Background TheWorld Economic Forum (WEF) has spawned a global network of elites called Young Global Leaders (YGLs) with significant influence on large corporations, politics, academia, and media. This article scrutinizes the idea that through this network, the WEF had a significant influence on the scale and scope of the non-pharmaceutical interventions (NPIs) implemented in response to the COVID-19 crisis. We tested for associations between the country-level distribution of YGLs and the intensity and duration of the implemented NPIs summarized by the Government Response Severity Index (GRSI). Materials and methods The number and category of YGLs per country was extracted from the WEF website. We also extracted the maximum and median GRSI values for three time periods: (i) the beginning of the first wave of the pandemic (March 1, 2020, to April 30, 2020), (ii) the height of the second wave in Europe (December 1, 2020, to January 31, 2021), and (iii) the approximate first year (March 1, 2020, to January 31, 2021). Being a precondition for causality, any association between the total or category-specific number of YGLs and the GRSI values in each time period was evaluated using Spearman's ρ correlation coefficients and polynomial regression, respectively. Results There was a highly significant positive correlation between the total number of YGLs in a country and the median (ρ = 0.36, p = 2.5×10
-7 ) and maximum (ρ = 0.34, p = 1.6×10-6 ) GRSI during the second wave of the pandemic, but not during the first wave. The total number of YGLs was also a significant predictor of higher median GRSI during the second wave of the pandemic in the best-fitting (four-degree) polynomial regression model (p<0.01); additional significant and positive predictor in this model was a country's location within Europe or South America, respectively (p<0.01). Investigating an influence-weighted number of YGLs in business, politics, and civic society separately yielded no significant associations with NPI severity for any of the three time periods. Conclusions As there were significant correlations during the second, but not the first wave of the pandemic, we conclude that the WEF might not have been the origin of but rather an echo-chamber or amplifier for certain opinions and strategies that were formed and implemented during or before the first months of the COVID-19 crisis. Future qualitative studies may reveal putative causal mechanisms underlying our observed correlations., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Klement et al.)- Published
- 2022
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19. Why do people consent to receiving SARS-CoV-2 vaccinations? A representative survey in Germany.
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Walach H, Ofner M, Ruof V, Herbig M, and Klement RJ
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- Germany epidemiology, Humans, Informed Consent, SARS-CoV-2, Surveys and Questionnaires, Vaccination, COVID-19 prevention & control, COVID-19 Vaccines therapeutic use
- Abstract
Objective: To answer the question: Why do people consent to being vaccinated with novel vaccines against SARS-CoV-2?, Design: Representative survey., Setting: Online panel., Participants: 1032 respondents of the general German population., Method: A representative survey among German citizens in November/December 2021 that resulted in 1032 complete responses on vaccination status, sociodemographic parameters and opinions about the COVID-19 situation., Results: Almost 83% of the respondents were vaccinated. The major motivation was fear of medical consequences of an infection and the wish to lead a normal life again. The major motivation to be not vaccinated was the fear of side effects and scepticism about long-term effectiveness and safety. Sixteen per cent of vaccinated respondents reported some serious side effect, while more than 30% reported health improvements, mostly due to the relief of psychological stress and social reintegration. We also validated a 'Corona Orthodoxy Score-COS' consisting of seven items reflecting opinions on COVID-19. The scale is reliable (alpha=0.76) and unidimensional. The COS was a highly significant predictor of vaccination status and readiness to be vaccinated in a multivariable logistic regression model. Those who were vaccinated were more likely to live in smaller households (OR=0.82, p=0.024), had a higher income (OR=1.27, p<0.001), a higher COS score (OR 1.4, p<0.0001) and used less alternative media (OR=0.44, p=0.0024) and scientific publications (OR=0.42, p=0.011) as information sources., Conclusions: The major motives for being vaccinated are fear of medical symptoms and the wish to lead a normal life. Those not wanting to be vaccinated cite a lack of knowledge regarding long-term safety and side effects as reasons. This can likely only be overcome by careful and active long-term efficacy and safety monitoring., Competing Interests: Competing interests: MH is the CEO of the company that conducted the survey. HW held an endowed chair sponsored by Heel pharmaceutical company, a producer of homeopathic remedies., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2022
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20. Identifying factors associated with COVID-19 related deaths during the first wave of the pandemic in Europe.
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Klement RJ and Walach H
- Subjects
- Aged, Europe epidemiology, Humans, Pandemics prevention & control, SARS-CoV-2, Vitamin D, COVID-19 epidemiology, Influenza, Human epidemiology
- Abstract
Aim: To clarify the high variability in COVID-19-related deaths during the first wave of the pandemic, we conducted a modeling study using publicly available data., Materials and Methods: We used 13 population- and country-specific variables to predict the number of population-standardized COVID-19-related deaths in 43 European countries using generalized linear models: the test-standardized number of SARS-CoV-2-cases, population density, life expectancy, severity of governmental responses, influenza-vaccination coverage in the elderly, vitamin D status, smoking and diabetes prevalence, cardiovascular disease death rate, number of hospital beds, gross domestic product, human development index and percentage of people older than 65 years., Results: We found that test-standardized number of SARS-CoV-2-cases and flu vaccination coverage in the elderly were the most important predictors, together with vitamin D status, gross domestic product, population density and government response severity explaining roughly two-thirds of the variation in COVID-19 related deaths. The latter variable was positively, but only weakly associated with the outcome, i.e., deaths were higher in countries with more severe government response. Higher flu vaccination coverage and low vitamin D status were associated with more COVID-19 related deaths. Most other predictors appeared to be negligible., Conclusion: Adequate vitamin D levels are important, while flu-vaccination in the elderly and stronger government response were putative aggravating factors of COVID-19 related deaths. These results may inform protection strategies against future infectious disease outbreaks., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Klement and Walach.)
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- 2022
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21. The risk-benefit ratio of Covid-19 vaccines: Publication policy by retraction does nothing to improve it.
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Walach H, Klement RJ, and Aukema W
- Abstract
Competing Interests: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.
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- 2022
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22. Ketogenic diets consumed during radio-chemotherapy have beneficial effects on quality of life and metabolic health in patients with rectal cancer.
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Klement RJ, Meyer D, Kanzler S, and Sweeney RA
- Subjects
- Body Composition, Humans, Quality of Life, Surveys and Questionnaires, Diet, Ketogenic, Rectal Neoplasms therapy
- Abstract
Purpose: Interest in ketogenic diets (KDs) as complementary nutritional treatments for cancer patients is rising, although some skepticism about their safety exists. We, therefore, studied the effects of KDs on quality of life and blood parameters in rectal cancer patients undergoing radio-chemotherapy., Methods: EORTC-QLQ30 questionnaire scores and different metabolic and hormonal blood parameters were obtained prior to, in the middle of and at the end of radiotherapy within the KETOCOMP study (ClinicalTrials.gov Identifier: NCT02516501). A total of 18 patients consuming a KD were compared to 23 patients consuming their standard diet (SD). Baseline-end differences were measured using Wilcoxon tests, and repeated measures analysis was performed using linear mixed effects models., Results: Eighty-nine percent of patients on the KD reported subjectively feeling good or very good, but roughly half of them rated the daily routine implementation as difficult. Only the SD group experienced significant declines in physical and role functioning, while the KD group improved in role (p = 0.045), emotional (p = 0.018) and social functioning (p = 0.009).Urinary frequency, buttock pain and fatigue significantly increased in the SD group, but to a much lesser extent in the KD group. Several biomarkers of metabolic health (gamma-glutamyl-transpeptidase, triglyceride-glucose index, HDL cholesterol/triglyceride ratio, and free T3) improved in the KD, but not the SD group., Conclusions: Despite being perceived as difficult to implement by ≈50% of patients, KDs are feasible as complementary therapies alongside radio-chemotherapy and associated with subjective well-being. The hypothesis that they exert beneficial effects on quality of life and metabolic health in rectal cancer patients is supported by our data., Trial Registration: ClinicalTrials.gov identifier NCT02516501, registered Aug 6th 2015., (© 2021. Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2022
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23. Accelerated hyper-versus normofractionated radiochemotherapy with temozolomide in patients with glioblastoma: a multicenter retrospective analysis.
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Klement RJ, Popp I, Kaul D, Ehret F, Grosu AL, Polat B, Sweeney RA, and Lewitzki V
- Subjects
- Antineoplastic Agents, Alkylating therapeutic use, Follow-Up Studies, Frailty, Humans, Retrospective Studies, Survival Analysis, Treatment Outcome, Brain Neoplasms therapy, Chemoradiotherapy methods, Glioblastoma therapy, Temozolomide therapeutic use
- Abstract
Background and Purpose: The standard treatment of glioblastoma patients consists of surgery followed by normofractionated radiotherapy (NFRT) with concomitant and adjuvant temozolomide chemotherapy. Whether accelerated hyperfractionated radiotherapy (HFRT) yields comparable results to NFRT in combination with temozolomide has only sparsely been investigated. The objective of this study was to compare NFRT with HFRT in a multicenter analysis., Materials and Methods: A total of 484 glioblastoma patients from four centers were retrospectively pooled and analyzed. Three-hundred-ten and 174 patients had been treated with NFRT (30 × 1.8 Gy or 30 × 2 Gy) and HFRT (37 × 1.6 Gy or 30 × 1.8 Gy twice/day), respectively. The primary outcome of interest was overall survival (OS) which was correlated with patient-, tumor- and treatment-related variables via univariable and multivariable Cox frailty models. For multivariable modeling, missing covariates were imputed using multiple imputation by chained equations, and a sensitivity analysis was performed on the complete-cases-only dataset., Results: After a median follow-up of 15.7 months (range 0.8-88.6 months), median OS was 16.9 months (15.0-18.7 months) in the NFRT group and 14.9 months (13.2-17.3 months) in the HFRT group (p = 0.26). In multivariable frailty regression, better performance status, gross-total versus not gross-total resection, MGMT hypermethylation, IDH mutation, smaller planning target volume and salvage therapy were significantly associated with longer OS (all p < 0.01). Treatment differences (HFRT versus NFRT) had no significant effect on OS in either univariable or multivariable analysis., Conclusions: Since HFRT with temozolomide was not associated with worse OS, we assume HFRT to be a potential option for patients wishing to shorten their treatment time., (© 2021. The Author(s).)
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- 2022
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24. The Epistemology of a Positive SARS-CoV-2 Test.
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Klement RJ and Bandyopadhyay PS
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- Bayes Theorem, COVID-19 virology, COVID-19 Testing methods, Coinfection virology, Humans, COVID-19 diagnosis, COVID-19 Testing standards, Coinfection diagnosis, Health Knowledge, Attitudes, Practice, Models, Theoretical, SARS-CoV-2 isolation & purification
- Abstract
We investigate the epistemological consequences of a positive polymerase chain reaction SARS-CoV test for two relevant hypotheses: (i) V is the hypothesis that an individual has been infected with SARS-CoV-2; (ii) C is the hypothesis that SARS-CoV-2 is the cause of flu-like symptoms in a given patient. We ask two fundamental epistemological questions regarding each hypothesis: First, how much confirmation does a positive test lend to each hypothesis? Second, how much evidence does a positive test provide for each hypothesis against its negation? We respond to each question within a formal Bayesian framework. We construe degree of confirmation as the difference between the posterior probability of the hypothesis and its prior, and the strength of evidence for a hypothesis against its alternative in terms of their likelihood ratio. We find that test specificity-and coinfection probabilities when making inferences about C-were key determinants of confirmation and evidence. Tests with < 87% specificity could not provide strong evidence (likelihood ratio > 8) for V against ¬V regardless of sensitivity. Accordingly, low specificity tests could not provide strong evidence in favor of C in all plausible scenarios modeled. We also show how a positive influenza A test disconfirms C and provides weak evidence against C in dependence on the probability that the patient is influenza A infected given that his/her symptoms are not caused by SARS-CoV-2. Our analysis points out some caveats that should be considered when attributing symptoms or death of a positively tested patient to SARS-CoV-2., (© 2020. Springer Nature B.V.)
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- 2021
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25. Stereotactic or conformal radiotherapy for adrenal metastases: Patient characteristics and outcomes in a multicenter analysis.
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Buergy D, Würschmidt F, Gkika E, Hörner-Rieber J, Knippen S, Gerum S, Balermpas P, Henkenberens C, Voglhuber T, Kornhuber C, Barczyk S, Röper B, Rashid A, Blanck O, Wittig A, Herold HU, Brunner TB, Klement RJ, Kahl KH, Ciernik IF, Ottinger A, Izaguirre V, Putz F, König L, Hoffmann M, Combs SE, Guckenberger M, and Boda-Heggemann J
- Subjects
- Aged, Aged, 80 and over, Databases, Factual, Female, Humans, Male, Middle Aged, Palliative Care, Radiosurgery, Radiotherapy Dosage, Radiotherapy, Conformal, Retrospective Studies, Survival Analysis, Treatment Outcome, Adrenal Gland Neoplasms radiotherapy, Adrenal Gland Neoplasms secondary, Carcinoma, Non-Small-Cell Lung radiotherapy, Lung Neoplasms radiotherapy, Small Cell Lung Carcinoma radiotherapy
- Abstract
To report outcome (freedom from local progression [FFLP], overall survival [OS] and toxicity) after stereotactic, palliative or highly conformal fractionated (>12) radiotherapy (SBRT, Pall-RT, 3DCRT/IMRT) for adrenal metastases in a retrospective multicenter cohort within the framework of the German Society for Radiation Oncology (DEGRO). Adrenal metastases treated with SBRT (≤12 fractions, biologically effective dose [BED10] ≥ 50 Gy), 3DCRT/IMRT (>12 fractions, BED10 ≥ 50 Gy) or Pall-RT (BED10 < 50 Gy) were eligible for this analysis. In addition to unadjusted FFLP (Kaplan-Meier/log-rank), we calculated the competing-risk-adjusted local recurrence rate (CRA-LRR). Three hundred twenty-six patients with 366 metastases were included by 21 centers (median follow-up: 11.7 months). Treatment was SBRT, 3DCRT/IMRT and Pall-RT in 260, 27 and 79 cases, respectively. Most frequent primary tumors were non-small-cell lung cancer (NSCLC; 52.5%), SCLC (16.3%) and melanoma (6.7%). Unadjusted FFLP was higher after SBRT vs Pall-RT (P = .026) while numerical differences in CRA-LRR between groups did not reach statistical significance (1-year CRA-LRR: 13.8%, 17.4% and 27.7%). OS was longer after SBRT vs other groups (P < .05) and increased in patients with locally controlled metastases in a landmark analysis (P < .0001). Toxicity was mostly mild; notably, four cases of adrenal insufficiency occurred, two of which were likely caused by immunotherapy or tumor progression. Radiotherapy for adrenal metastases was associated with a mild toxicity profile in all groups and a favorable 1-year CRA-LRR after SBRT or 3DCRT/IMRT. One-year FFLP was associated with longer OS. Dose-response analyses for the dataset are underway., (© 2021 The Authors. International Journal of Cancer published by John Wiley & Sons Ltd on behalf of Union for International Cancer Control.)
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- 2021
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26. Impact of a ketogenic diet intervention during radiotherapy on body composition: IV. Final results of the KETOCOMP study for rectal cancer patients.
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Klement RJ, Koebrunner PS, Meyer D, Kanzler S, and Sweeney RA
- Subjects
- Adult, Aged, Body Weight, Female, Humans, Male, Middle Aged, Muscle, Skeletal physiopathology, Radiotherapy, Adjuvant, Rectal Neoplasms physiopathology, Treatment Outcome, Body Composition, Diet, Ketogenic methods, Neoadjuvant Therapy methods, Rectal Neoplasms therapy
- Abstract
Background & Aims: Obesity and low muscle mass are associated with worse outcomes of colorectal cancer patients. We conducted a controlled trial to study the impact of a ketogenic diet (KD) based on natural foods versus an unspecified standard diet (SD) on body composition in rectal cancer patients undergoing radiotherapy., Methods: Patients with non-metastasized rectal cancer were allocated to either the KD (N = 24) or the SD (N = 25) group during radiotherapy. Body composition was measured weekly by bioimpedance analysis and analyzed using linear mixed effects models. Pathologic response in patients undergoing neoadjuvant treatment was evaluated at the time of surgery., Results: A total of 18 KD and 23 SD patients completed the study and were eligible for analysis. The SD group experienced no noteworthy changes in any body composition parameter. In contrast, patients in the KD group lost significant amounts of body weight and fat mass, averaging 0.5 and 0.65 kg/week (p < 0.0001). There was a rapid loss of intracellular water consistent with initial intramuscular glycogen and water depletion, but skeletal muscle tissue was conserved. Pathological tumor responses were somewhat greater in the KD group, with a larger mean Dworak regression grade (p = 0.072) and larger percentage of near-complete (yT0N0 or yT1N1) responses (43 versus 15%, p = 0.116) that almost reached statistical significance in intention-to-treat analysis (50% versus 14%, p = 0.018)., Conclusions: In rectal cancer patients undergoing curative radiotherapy, a KD significantly reduced body weight and fat mass while preserving skeletal muscle mass. We could demonstrate a trend for KDs contributing synergistically to pathological tumor response, a finding in line with preclinical data that warrants future confirmation in larger studies., Trial Registration: ClinicalTrials.gov identifier: NCT02516501, registered on August 06, 2015., Competing Interests: Conflict of interest RJK has received an honorarium from the company vitaflo for giving a talk about the objectives and preliminary results of the KETOCOMP study. RJK, PSK and RAS follow a KD occasionally. No other potential conflicts of interest, in particular no financial conflicts of interest, exist. The companies providing product samples for this study had no influence on the design, data collection and analysis, and none of the authors has any business relationship with them., (Copyright © 2021 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)
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- 2021
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27. Retracted: The Safety of COVID-19 Vaccinations-We Should Rethink the Policy.
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Walach H, Klement RJ, and Aukema W
- Abstract
Background : COVID-19 vaccines have had expedited reviews without sufficient safety data. We wanted to compare risks and benefits. Method : We calculated the number needed to vaccinate (NNTV) from a large Israeli field study to prevent one death. We accessed the Adverse Drug Reactions (ADR) database of the European Medicines Agency and of the Dutch National Register (lareb.nl) to extract the number of cases reporting severe side effects and the number of cases with fatal side effects. Result : The NNTV is between 200-700 to prevent one case of COVID-19 for the mRNA vaccine marketed by Pfizer, while the NNTV to prevent one death is between 9000 and 50,000 (95% confidence interval), with 16,000 as a point estimate. The number of cases experiencing adverse reactions has been reported to be 700 per 100,000 vaccinations. Currently, we see 16 serious side effects per 100,000 vaccinations, and the number of fatal side effects is at 4.11/100,000 vaccinations. For three deaths prevented by vaccination we have to accept two inflicted by vaccination. Conclusions : This lack of clear benefit should cause governments to rethink their vaccination policy.
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- 2021
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28. A ketogenic diet consumed during radiotherapy improves several aspects of quality of life and metabolic health in women with breast cancer.
- Author
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Klement RJ, Weigel MM, and Sweeney RA
- Subjects
- Adult, Biomarkers blood, Breast Neoplasms blood, Female, Humans, Radiation Injuries etiology, Sleep Quality, Treatment Outcome, Breast Neoplasms psychology, Breast Neoplasms radiotherapy, Diet, Ketogenic psychology, Quality of Life, Radiation Injuries prevention & control
- Abstract
Background & Aims: Ketogenic diets (KDs) have been proposed as complementary nutritional treatments for cancer patients. Because it is important to gain knowledge about the safety of KDs adopted during cancer therapy, we studied the effects of KDs on quality of life and blood parameters in women with early-stage breast cancer undergoing radiotherapy., Methods: A total of 29 patients consuming a KD were compared to 30 patients consuming their standard diet (SD) with respect to EORTC-QLQ30 questionnaire scores and different metabolic and hormonal blood parameters that were obtained prior to, in the middle of and at the end of radiotherapy. Baseline-to-end differences were assessed using Wilcoxon tests, and longitudinal changes were analyzed using linear mixed effects models., Results: Compared to the SD, women consuming a KD experienced significant improvements in emotional functioning, social functioning, sleep quality, future perspectives and systemic therapy side effects (all p-values <0.01). While breast symptoms increased significantly in both groups, the increase was less pronounced in the KD group. There was no hint of a detrimental effect of the KDs on either liver or kidney function; in contrast, biomarkers of metabolic health (gamma-glutamyl-transpeptidase, creatinine, triglycerides, IGF-1, free T3) significantly improved in the KD, but not the SD group., Conclusions: These data support the hypothesis that consuming a KD during radiotherapy is safe for women with breast cancer and has the potential to improve quality of life and metabolic health. CLINICALTRIALS., Gov Identifier: NCT02516501., Competing Interests: Conflict of interest All authors declare that they have no conflicts of interest associated with this research., (Copyright © 2021 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)
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- 2021
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29. Bayes Lines Tool (BLT): a SQL-script for analyzing diagnostic test results with an application to SARS-CoV-2-testing.
- Author
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Aukema W, Malhotra BR, Goddek S, Kämmerer U, Borger P, McKernan K, and Klement RJ
- Subjects
- Bayes Theorem, Diagnostic Tests, Routine, Humans, Sensitivity and Specificity, COVID-19 diagnosis, COVID-19 epidemiology, SARS-CoV-2
- Abstract
The performance of diagnostic tests crucially depends on the disease prevalence, test sensitivity, and test specificity. However, these quantities are often not well known when tests are performed outside defined routine lab procedures which make the rating of the test results somewhat problematic. A current example is the mass testing taking place within the context of the world-wide SARS-CoV-2 crisis. Here, for the first time in history, laboratory test results have a dramatic impact on political decisions. Therefore, transparent, comprehensible, and reliable data is mandatory. It is in the nature of wet lab tests that their quality and outcome are influenced by multiple factors reducing their performance by handling procedures, underlying test protocols, and analytical reagents. These limitations in sensitivity and specificity have to be taken into account when calculating the real test results. As a resolution method, we have developed a Bayesian calculator, the Bayes Lines Tool (BLT), for analyzing disease prevalence, test sensitivity, test specificity, and, therefore, true positive, false positive, true negative, and false negative numbers from official test outcome reports. The calculator performs a simple SQL (Structured Query Language) query and can easily be implemented on any system supporting SQL. We provide an example of influenza test results from California, USA, as well as two examples of SARS-CoV-2 test results from official government reports from The Netherlands and Germany-Bavaria, to illustrate the possible parameter space of prevalence, sensitivity, and specificity consistent with the observed data. Finally, we discuss this tool's multiple applications, including its putative importance for informing policy decisions., Competing Interests: No competing interests were disclosed., (Copyright: © 2021 Aukema W et al.)
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- 2021
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30. In Regard to Ohri et al.
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Klement RJ, Andratschke N, and Guckenberger M
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- 2021
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31. Vitamin D Resistance as a Possible Cause of Autoimmune Diseases: A Hypothesis Confirmed by a Therapeutic High-Dose Vitamin D Protocol.
- Author
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Lemke D, Klement RJ, Schweiger F, Schweiger B, and Spitz J
- Subjects
- Autoimmune Diseases diagnosis, Autoimmune Diseases drug therapy, Biomarkers, Drug Resistance, Humans, Receptors, Calcitriol metabolism, Vitamin D administration & dosage, Vitamin D therapeutic use, Autoimmune Diseases etiology, Autoimmune Diseases metabolism, Disease Susceptibility, Vitamin D metabolism
- Abstract
Vitamin D
3 (cholecalciferol) is a secosteroid and prohormone which is metabolized in various tissues to the biologically most active vitamin D hormone 1,25(OH)2 D3 (calcitriol). 1,25(OH)2 D3 has multiple pleiotropic effects, particularly within the immune system, and is increasingly utilized not only within prophylaxis, but also within therapy of various diseases. In this context, the latest research has revealed clinical benefits of high dose vitamin D3 therapy in autoimmune diseases. The necessity of high doses of vitamin D3 for treatment success can be explained by the concept of an acquired form of vitamin D resistance. Its etiology is based on the one hand on polymorphisms within genes affecting the vitamin D system, causing susceptibility towards developing low vitamin D responsiveness and autoimmune diseases; on the other hand it is based on a blockade of vitamin D receptor signaling, e.g. through pathogen infections. In this paper, we review observational and mechanistic evidence for the acquired vitamin D resistance hypothesis. We particularly focus on its clinical confirmation from our experience of treating multiple sclerosis patients with the so-called Coimbra protocol, in which daily doses up to 1000 I.U. vitamin D3 per kg body weight can be administered safely. Parathyroid hormone levels in serum thereby provide the key information for finding the right dose. We argue that acquired vitamin D resistance provides a plausible pathomechanism for the development of autoimmune diseases, which could be treated using high-dose vitamin D3 therapy., Competing Interests: DL and BS are certified Coimbra practitioners. BS owns the practice that apply the here described Coimbra protocol to patients with autoimmune diseases. The remaining authors declare that the research was conducted in the absense of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Lemke, Klement, Schweiger, Schweiger and Spitz.)- Published
- 2021
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32. Low Carb and Ketogenic Diets Increase Quality of Life, Physical Performance, Body Composition, and Metabolic Health of Women with Breast Cancer.
- Author
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Kämmerer U, Klement RJ, Joos FT, Sütterlin M, and Reuss-Borst M
- Subjects
- Adult, Aged, Diet, Diet, Carbohydrate-Restricted, Female, Humans, Lipoproteins, HDL, Middle Aged, Surveys and Questionnaires, Triglycerides, Body Composition, Breast Neoplasms rehabilitation, Diet, Ketogenic, Physical Functional Performance, Quality of Life
- Abstract
Breast cancer (BC) patients often ask for a healthy diet. Here, we investigated a healthy standard diet (SD), a low carb diet (LCD), and a ketogenic diet (KD) for BC patients during the rehabilitation phase. KOLIBRI was an open-label non-randomized one-site nutritional intervention trial, combining inpatient and outpatient phases for 20 weeks. Female BC patients ( n = 152; mean age 51.7 years) could select their diet. Data collected were: Quality of life (QoL), spiroergometry, body composition, and blood parameters. In total 30, 92, and 30 patients started the KD, LCD, and SD, respectively. Of those, 20, 76, and 25 completed the final examination. Patients rated all diets as feasible in daily life. All groups enhanced QoL, body composition, and physical performance. LCD participants showed the most impressive improvement in QoL aspects. KD participants finished with a very good physical performance and muscle/fat ratio. Despite increased cholesterol levels, KD patients had the best triglyceride/high-density lipoprotein (HDL) ratio and homeostatic model assessment of insulin resistance index (HOMA-IR). Most metabolic parameters significantly improved in the LCD group. SD participants ended with remarkably low cholesterol levels but did not improve triglyceride/HDL or HOMA-IR. In conclusion, both well-defined KDs and LCDs are safe and beneficial for BC patients and can be recommended during the rehabilitation phase.
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- 2021
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33. High-dose re-irradiation of intracranial lesions - Efficacy and safety including dosimetric analysis based on accumulated EQD2Gy dose EQD calculation.
- Author
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Stiefel I, Schröder C, Tanadini-Lang S, Pytko I, Vu E, Klement RJ, Guckenberger M, and Andratschke N
- Abstract
Introduction: The use of cranial re-irradiation is growing with improving overall survival and the advent of high-precision radiotherapy techniques. Still the value of re-irradiation needs careful evaluation regarding safety and efficacy. We analyzed dosimetric and clinical data of patients receiving cranial re-irradiation using EQD2 sum plans., Methods and Material: We retrospectively analyzed the data of 76 patients who received repeated cranial radiotherapy from 02/2013 to 09/2016. 34 patients suffered from recurrent primary brain tumors, 42 from brain metastases. Dosimetric analysis was performed accumulating EQD2 dose distributions based on rigid image registration. Clinical and radiological data was collected at follow-ups including toxicity, local control and overall survival., Results: In total 76 patients had at least 2 courses of intracranial radiotherapy. The median accumulated prescription EQD2 dose was 96.5 Gy
2 for all radiation courses combined. The median D(0.1 cc) of the brain for patients receiving more than 100 Gy2 was 114 Gy2 with a highest dose of 161.5 Gy2 . 74% of patients suffered from low grade (G1-G2) acute toxicity, only two high grade (>G3) toxicities were recorded.Median overall survival from the time of first re-irradiation was 57 weeks (range 4-186 weeks). The median time to local failure for patients with a primary brain tumor was not reached and 24 weeks (range 1-77 weeks) for patients with brain metastases., Conclusion: Repeated radiotherapy appears both safe and efficient in patients with recurrent primary or secondary brain tumors with doses to the brain up to 120 Gy2 EQD2, doses below 100 Gy2 for brainstem and doses below 75 Gy2 EQD2 to chiasm and optic nerves., 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 Published by Elsevier B.V. on behalf of European Society for Radiotherapy and Oncology.)- Published
- 2021
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34. Low Vitamin D Status in a Cancer Patient Population from Franconia, Germany.
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Klement RJ, Koebrunner PS, Krage K, and Sweeney RA
- Subjects
- Adult, Aged, C-Reactive Protein analysis, COVID-19 blood, COVID-19 mortality, COVID-19 virology, Dietary Supplements, Female, Humans, Male, Middle Aged, Neoplasms blood, Prospective Studies, SARS-CoV-2, Vitamin D analogs & derivatives, Vitamin D Deficiency blood, COVID-19 complications, Neoplasms radiotherapy, Vitamin D blood, Vitamin D Deficiency complications
- Abstract
Background: Vitamin D has been shown to be associated with reduced risk and severity of COVID-19 and exerts regulating effects on all hallmarks of cancer. The goal of this study was to analyze the vitamin D status of a cancer patient cohort from our clinic in the Franconian region, Germany., Methods: 25-hydroxyvitamin D concentrations were available for 116 patients included in prospective trials in our clinic. Associations of vitamin D with anthropometric and blood parameters were investigated using Kendall's τ correlation coefficients and linear regression., Results: A total of 57 patients (49.1%) were vitamin D deficient (<20 ng/mL), and 92.2% did not meet the recommended vitamin D level of 40 ng/mL. There was a strong negative association between vitamin D and leukocyte count (τ = -0.173, p = 0.007) and C-reactive protein concentration (τ = -0.172, p = 0.007). In linear regression, the most important variables for predicting vitamin D levels were (in order of decreasing importance) season, fat mass index, platelet, and leukocyte count., Conclusions: Despite appeals towards medical societies to target widespread vitamin D deficiency in Germany more than 10 years ago, our data indicate that these have been without avail. Low vitamin D levels in cancer patients should be corrected using reasonable sun exposure and supplements., (© 2020 S. Karger AG, Basel.)
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- 2021
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35. Comments on "Inhibition of the ketolytic acetyl CoA supply to tumors could be their 'Achilles heel'".
- Author
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Klement RJ and Koebrunner PS
- Subjects
- Acetyl Coenzyme A, Humans, Neoplasms
- Published
- 2020
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36. Short-term effects of a Paleolithic lifestyle intervention in breast cancer patients undergoing radiotherapy: a pilot and feasibility study.
- Author
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Klement RJ, Koebrunner PS, Krage K, Weigel MM, and Sweeney RA
- Subjects
- Adult, Aged, Body Composition physiology, Body Weight, Breast Neoplasms blood, Breast Neoplasms rehabilitation, Feasibility Studies, Female, Humans, Middle Aged, Pilot Projects, Propensity Score, Treatment Outcome, Weight Loss physiology, Breast Neoplasms diet therapy, Breast Neoplasms radiotherapy, Diet, Paleolithic, Exercise physiology, Life Style
- Abstract
Evolutionary principles are rarely considered in clinical oncology. We here aimed to test the feasibility and effects of a dietary and physical activity intervention based on evolutionary considerations in an oncological setting. A total of 13 breast cancer patients referred to our clinic for curative radiotherapy were recruited for this pilot study. The women were supposed to undertake a "Paleolithic lifestyle" (PL) intervention consisting of a Paleolithic diet and daily outdoor activity of at least 30 min duration while undergoing radiotherapy. Body composition was measured weekly by bioimpedance analysis. Blood parameters were assessed before, during, and at the end of radiotherapy. A control group on an unspecified standard diet (SD) was assigned by propensity score matching. A total of eleven patients completed the study. The majority of patients (64%) reported feeling good or very good during the intervention. The intervention group experienced an average decrease of 0.4 kg body weight (p < 0.001) and 0.34 kg (p < 0.001) fat mass per week, but fat-free and skeletal muscle mass were not significantly affected. Vitamin D levels increased slightly from 23.8 (11-37.3) ng/ml to 25.1 (22.6-41.6) ng/ml (p = 0.053). β-hydroxybutyrate levels were significantly increased and triglycerides and free T3 hormone levels significantly reduced by the PL intervention. This pilot study shows that adoption of a PL intervention during curative radiotherapy of breast cancer patients is feasible and able to reduce fat mass. Daily outdoor activity could eliminate vitamin D deficiency (vitamin D < 20 ng/ml). Future studies are needed to confirm these findings.
- Published
- 2020
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37. Systems Thinking About SARS-CoV-2.
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Klement RJ
- Subjects
- Humans, Public Health, Systems Analysis, COVID-19, SARS-CoV-2
- Published
- 2020
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38. Assessing successful completion of calorie restriction studies for the prevention and treatment of cancer.
- Author
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Champ CE and Klement RJ
- Subjects
- Diet, Energy Intake, Exercise, Humans, Pilot Projects, Caloric Restriction, Neoplasms prevention & control
- Abstract
Objectives: Calorie restriction (CR) >20% has been hypothesized to aid cancer prevention and treatment. Yet, to our knowledge, there is a lack of reported studies in humans describing tolerance, adherence, or efficacy, and unpublished and incomplete dietary studies may indicate lack of tolerability and compliance. The aim of this study was to assess registered clinical trials using CR for cancer treatment and prevention, rates of completion, and published reports to determine whether barriers to publication may be indicative of either negative studies, or incompletion due to unreported compliance issues., Methods: Current registered clinical trials assessing CR in cancer prevention and treatment were assessed at clinicaltrials.gov and the International Clinical Trials Registry at the World Health Organization. Assessment of study completion and publication was calculated and compared with methods of CR used, as were rates of inactive and incomplete studies, dormant studies, time of dormancy, type of study, and generalizable conclusions., Results: Twenty-nine trials were registered assessing CR in cancer treatment or prevention. Of these studies, 18 met initial criteria, and only 4 had completed and published results. Three of these tested a CR regimen incorporating exercise or intermittent restriction. Target CR ranged from 500 to 1000 kcal/d, with one study aim of 20% CR; no study reported rates of actual calorie intake. The majority of dormant and unpublished studies (69%) used general dietary CR and was without update ranging from 265 to 2518 d. Only one study reported on the side effects of the CR regimen; compliance and adherence to the regimen was described in the four completed studies that reported results. Only two studies were registered as pilot studies testing the feasibility of CR., Conclusions: Poor completion and lack of reporting of results is apparent in the majority of studies assessing CR for cancer prevention or treatment. These findings should be considered during the design of future studies assessing dietary strategies for cancer prevention or treatment., (Copyright © 2020 Elsevier Inc. All rights reserved.)
- Published
- 2020
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39. Impact of a ketogenic diet intervention during radiotherapy on body composition: III-final results of the KETOCOMP study for breast cancer patients.
- Author
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Klement RJ, Champ CE, Kämmerer U, Koebrunner PS, Krage K, Schäfer G, Weigel M, and Sweeney RA
- Subjects
- Adult, Aged, Breast Neoplasms physiopathology, Breast Neoplasms radiotherapy, Female, Humans, Middle Aged, Patient Safety, Prospective Studies, Treatment Outcome, Body Composition, Body Weight, Breast Neoplasms diet therapy, Diet, Ketogenic methods, Quality of Life
- Abstract
Background: Obesity and low muscle mass are associated with worse outcomes of breast cancer patients. We conducted a controlled trial to study the impact of a ketogenic diet (KD) based on natural foods versus an unspecified standard diet (SD) on body composition in breast cancer patients undergoing radiotherapy., Methods: Patients with non-metastasized breast cancer were allocated to either the KD (N = 32) or the SD (N = 31) during radiotherapy. Body composition was measured weekly by bioimpedance analysis. Blood parameters and quality of life were assessed before, during, and at the end of radiotherapy., Results: A total of 29 KD and 30 SD patients completed the study. During radiotherapy, mean and median fasting BHB concentrations in the KD group were 0.72 and 0.49 mmol/l (range 0.06-4.9) which was significantly higher than those in the SD group (p < 2.2 × 10
-16 ). There was a very small and insignificant increase in body weight and fat mass in the SD group, as well as a decrease of fat free mass. In contrast, patients in the KD group lost body weight and fat free and skeletal muscle mass quickly after diet onset, which for the most part was related to water losses. The KD did not cause further substantial changes in fat free or skeletal muscle mass, but was associated with a gradual decrease of 0.4 kg body weight and fat mass per week (p < 0.0001). The KD significantly decreased free T3 levels by 0.06 pg/ml/week (p = 6.3 × 10-5 ). Global quality of life remained stable in the SD group but increased in the KD group from a score of 66.7 to 75.0 (p = 0.20)., Conclusions: In breast cancer patients undergoing curative radiotherapy, a KD based on natural foods is feasible. After initial water losses, the KD tends to reduce body weight and fat mass while preserving fat free and skeletal muscle mass., Trial Registration: ClinicalTrials.gov identifier: NCT02516501 , registered on August 06, 2015.- Published
- 2020
- Full Text
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40. Face masks in radiation oncology clinics: based on evidence or source of mistakes?
- Author
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Klement RJ and Sweeney RA
- Subjects
- COVID-19, Coronavirus Infections transmission, Coronavirus Infections virology, Humans, Pandemics, Pneumonia, Viral transmission, Pneumonia, Viral virology, SARS-CoV-2, Betacoronavirus isolation & purification, Coronavirus Infections epidemiology, Evidence-Based Medicine, Masks standards, Masks statistics & numerical data, Pneumonia, Viral epidemiology, Radiation Oncology standards, Radiotherapy Setup Errors prevention & control
- Abstract
We here express our concern about a general decree to let patients wear face masks in radiation oncology clinics. We believe that potential risks associated with wearing masks, such as the risk of confounding patients, outweigh any benefits of such a policy for which evidence of protection from COVID-19 is generally weak. For asymptomatic patients, wearing masks in addition to hygiene standards will not provide additional protection of others and should be cautioned against.
- Published
- 2020
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41. The SARS-CoV-2 crisis: A crisis of reductionism?
- Author
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Klement RJ
- Published
- 2020
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42. Correlating Dose Variables with Local Tumor Control in Stereotactic Body Radiation Therapy for Early-Stage Non-Small Cell Lung Cancer: A Modeling Study on 1500 Individual Treatments.
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Klement RJ, Sonke JJ, Allgäuer M, Andratschke N, Appold S, Belderbos J, Belka C, Blanck O, Dieckmann K, Eich HT, Mantel F, Eble M, Hope A, Grosu AL, Nevinny-Stickel M, Semrau S, Sweeney RA, Hörner-Rieber J, Werner-Wasik M, Engenhart-Cabillic R, Ye H, Grills I, and Guckenberger M
- Subjects
- Aged, Aged, 80 and over, Dose-Response Relationship, Radiation, Female, Humans, Male, Middle Aged, Neoplasm Staging, Radiotherapy Planning, Computer-Assisted, Carcinoma, Non-Small-Cell Lung pathology, Carcinoma, Non-Small-Cell Lung radiotherapy, Lung Neoplasms pathology, Lung Neoplasms radiotherapy, Radiosurgery
- Abstract
Background: Large variation regarding prescription and dose inhomogeneity exists in stereotactic body radiation therapy (SBRT) for early-stage non-small cell lung cancer. The aim of this modeling study was to identify which dose metric correlates best with local tumor control probability to make recommendations regarding SBRT prescription., Methods and Materials: We combined 2 retrospective databases of patients with non-small cell lung cancer, yielding 1500 SBRT treatments for analysis. Three dose parameters were converted to biologically effective doses (BEDs): (1) the (near-minimum) dose prescribed to the planning target volume (PTV) periphery (yielding BED
min ); (2) the (near-maximum) dose absorbed by 1% of the PTV (yielding BEDmax ); and (3) the average between near-minimum and near-maximum doses (yielding BEDave ). These BED parameters were then correlated to the risk of local recurrence through Cox regression. Furthermore, BED-based prediction of local recurrence was attempted by logistic regression and fast and frugal trees. Models were compared using the Akaike information criterion., Results: There were 1500 treatments in 1434 patients; 117 tumors recurred locally. Actuarial local control rates at 12 and 36 months were 96.8% (95% confidence interval, 95.8%-97.8%) and 89.0% (87.0%-91.1%), respectively. In univariable Cox regression, BEDave was the best predictor of risk of local recurrence, and a model based on BEDmin had substantially less evidential support. In univariable logistic regression, the model based on BEDave also performed best. Multivariable classification using fast and frugal trees revealed BEDmax to be the most important predictor, followed by BEDave ., Conclusions: BEDave was generally better correlated with tumor control probability than either BEDmax or BEDmin . Because the average between near-minimum and near-maximum doses was highly correlated to the mean gross tumor volume dose, the latter may be used as a prescription target. More emphasis could be placed on achieving sufficiently high mean doses within the gross tumor volume rather than the PTV covering dose, a concept needing further validation., (Copyright © 2020 Elsevier Inc. All rights reserved.)- Published
- 2020
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43. Addressing the controversial role of ketogenic diets in cancer treatment.
- Author
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Klement RJ
- Subjects
- Animals, Diet, Ketogenic adverse effects, Humans, Ketosis metabolism, Neoplasms pathology, Neoplasms therapy, Diet, Ketogenic methods, Neoplasms diet therapy
- Published
- 2020
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44. Ketogenic diets in medical oncology: a systematic review with focus on clinical outcomes.
- Author
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Klement RJ, Brehm N, and Sweeney RA
- Subjects
- Body Composition, Clinical Trials as Topic, Combined Modality Therapy, Female, Glioblastoma mortality, Glioblastoma therapy, Glioma mortality, Glioma therapy, Humans, Male, Medical Oncology, Neoplasms diet therapy, Neoplasms mortality, Progression-Free Survival, Survival Rate, Diet, Ketogenic, Neoplasms therapy
- Abstract
Preclinical data provide evidence for synergism between ketogenic diets (KDs) and other oncological therapies. The aim of this systematic review was to summarize data from clinical studies that have tested KDs along with other treatments used within medical oncology. The PubMed database was searched using the key words "ketogenic" AND ("cancer" OR "glioblastoma"). A secondary search was conducted by screening the reference lists of relevant articles on this topic. Relevant studies for this review were defined as studies in which KDs were used complementary to surgery, radio-, chemo-, or targeted therapy and at least one of the following four outcomes were reported: (i) Overall survival (OS); (ii) progression-free survival (PFS); (iii) local control rate; (iv) body composition changes. Twelve papers reporting on 13 clinical studies were identified. Nine studies were prospective and six had a control group, but only two were randomized. KD prescription varied widely between studies and was described only rudimentarily in most papers. Adverse events attributed to the diet were rare and only minor (grade 1-2) except for one possibly diet-related grade 4 event. Studies reporting body composition changes found beneficial effects of KDs in both overweight and frail patient populations. Beneficial effects of KDs on OS and/or PFS were found in four studies including one randomized controlled trial. Studies in high-grade glioma patients were not sufficiently powered to prove efficacy. Evidence for beneficial effects of KDs during cancer therapy is accumulating, but more high-quality studies are needed to assess the overall strength of evidence.
- Published
- 2020
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45. The SARS-CoV-2 Crisis: Has Medicine Finally Entered a Reductionist Era?
- Author
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Klement RJ
- Subjects
- COVID-19, Humans, Prevalence, SARS-CoV-2, Sensitivity and Specificity, Betacoronavirus, Coronavirus Infections diagnosis, Coronavirus Infections epidemiology, Coronavirus Infections mortality, Pandemics, Pneumonia, Viral diagnosis, Pneumonia, Viral epidemiology, Pneumonia, Viral mortality, Systems Analysis
- Published
- 2020
- Full Text
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46. Estimation of the α/β ratio of non-small cell lung cancer treated with stereotactic body radiotherapy.
- Author
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Klement RJ, Sonke JJ, Allgäuer M, Andratschke N, Appold S, Belderbos J, Belka C, Dieckmann K, Eich HT, Flentje M, Grills I, Eble M, Hope A, Grosu AL, Semrau S, Sweeney RA, Hörner-Rieber J, Werner-Wasik M, Engenhart-Cabillic R, Ye H, and Guckenberger M
- Subjects
- Aged, Aged, 80 and over, Bayes Theorem, Cell Survival radiation effects, Dose Fractionation, Radiation, Female, Humans, Logistic Models, Male, Middle Aged, Models, Statistical, Neoplasm Recurrence, Local pathology, Radiation Dose Hypofractionation, Retrospective Studies, Carcinoma, Non-Small-Cell Lung pathology, Carcinoma, Non-Small-Cell Lung radiotherapy, Lung Neoplasms pathology, Lung Neoplasms radiotherapy, Radiosurgery methods
- Abstract
Background: High-dose hypofractionated radiotherapy should theoretically result in a deviation from the typical linear-quadratic shape of the cell survival curve beyond a certain threshold dose, yet no evidence for this hypothesis has so far been found in clinical data of stereotactic body radiotherapy treatment (SBRT) for early-stage non-small cell lung cancer (NSCLC). A pragmatic explanation is a larger α/β ratio than the conventionally assumed 10 Gy. We here attempted an estimation of the α/β ratio for NSCLC treated with SBRT using individual patient data., Materials and Methods: We combined two large retrospective datasets, yielding 1294 SBRTs (≤10 fractions) of early stage NSCLC. Cox proportional hazards regression, a logistic tumor control probability model and a biologically motivated Bayesian cure rate model were used to estimate the α/β ratio based on the observed number of local recurrences and accounting for tumor size., Results: A total of 109 local progressions were observed after a median of 17.7 months (range 0.6-76.3 months). Cox regression, logistic regression of 3 year tumor control probability and the cure rate model yielded best-fit estimates of α/β = 12.8 Gy, 14.9 Gy and 12-16 Gy (depending on the prior for α/β), respectively, although with large uncertainties that did not rule out the conventional α/β = 10 Gy., Conclusions: Clinicians can continue to use the simple LQ formalism to compare different SBRT treatment schedules for NSCLC. While α/β = 10 Gy is not ruled out by our data, larger values in the range 12-16 Gy are more probable, consistent with recent meta-regression analyses., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2020
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47. Accelerated hyperfractionated radiochemotherapy with temozolomide is equivalent to normofractionated radiochemotherapy in a retrospective analysis of patients with glioblastoma.
- Author
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Lewitzki V, Klement RJ, Kosmala R, Lisowski D, Flentje M, and Polat B
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Brain Neoplasms drug therapy, Brain Neoplasms radiotherapy, Child, Female, Glioblastoma drug therapy, Glioblastoma radiotherapy, Humans, Male, Middle Aged, Prognosis, Retrospective Studies, Young Adult, Antineoplastic Agents, Alkylating therapeutic use, Brain Neoplasms pathology, Chemoradiotherapy, Dose Fractionation, Radiation, Glioblastoma pathology, Temozolomide therapeutic use
- Abstract
Background: Current standard of treatment for newly diagnosed patients with glioblastoma (GBM) is surgical resection with adjuvant normofractionated radiotherapy (NFRT) combined with temozolomide (TMZ) chemotherapy. Hyperfractionated accelerated radiotherapy (HFRT) which was known as an option from randomized controlled trials before the temozolomide era has not been compared to the standard therapy in a randomized setting combined with TMZ., Methods: Data of 152 patients with newly diagnosed GBM treated from 10/2004 until 7/2018 at a single tertiary care institution were extracted from a clinical database and retrospectively analyzed. Thirty-eight patients treated with NFRT of 60 Gy in 30 fractions (34 with simultaneous and 2 with sequential TMZ) were compared to 114 patients treated with HFRT of 54.0 Gy in 30 fraction of 1.8 Gy twice daily (109 with simultaneous and 3 with sequential TMZ). The association between treatment protocol and other variables with overall survival (OS) was assessed using univariable and multivariable Cox regression analysis; the latter was performed using variables selected by the LASSO method., Results: Median overall survival (OS) was 20.3 month for the entire cohort. For patients treated with NFRT median OS was 24.4 months compared to 18.5 months in patients treated with HFRT (p = 0.131). In univariable regression analysis the use of dexamethasone during radiotherapy had a significant negative impact on OS in both patient groups, HR 2.21 (95% CI 1.47-3.31, p = 0.0001). In multivariable analysis adjusted for O6-methylguanine-DNA methyl-transferase (MGMT) promotor methylation status, salvage treatment and secondary GBM, the use of dexamethasone was still a negative prognostic factor, HR 1.95 (95% CI 1.21-3.13, p = 0.006). Positive MGMT-methylation status and salvage treatment were highly significant positive prognostic factors. There was no strong association between treatment protocol and OS (p = 0.504)., Conclusions: Our retrospective analysis supports the hypothesis of equivalence between HFRT and the standard protocol of treatment for GBM. For those patients who are willing to obtain the benefit of shortening the course of radiochemotherapy, HFRT may be an alternative with comparable efficacy although it was not yet tested in a large prospective randomized study against the current standard. The positive influence of salvage therapy and negative impact of concomitant use of corticosteroids should be addressed in future prospective trials. To confirm our results, we plan to perform a pooled analysis with other tertiary clinics in order to achieve better statistical reliability.
- Published
- 2019
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48. Risk factors for vertebral compression fracture after spine stereotactic body radiation therapy: Long-term results of a prospective phase 2 study.
- Author
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Mantel F, Sweeney RA, Klement RJ, Hawkins MA, Belderbos J, Ahmed M, Toussaint A, Polat B, Flentje M, and Guckenberger M
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Follow-Up Studies, Humans, Logistic Models, Male, Middle Aged, Prospective Studies, Radiosurgery methods, Risk Factors, Spinal Neoplasms secondary, Fractures, Compression etiology, Radiation Injuries etiology, Radiosurgery adverse effects, Spinal Fractures etiology, Spinal Neoplasms radiotherapy
- Abstract
Purpose: To identify frequency, clinical relevance and risk factors for vertebral compression fracture (VCF) after spine stereotactic body radiation therapy (SBRT) with long-term follow up (FU)., Methods: From 2012 to 2015, 61 lesions (56 patients) were treated within a prospective multicenter phase 2 study (NCT01594892) of SBRT for painful vertebral metastases. Post-SBRT VCF were identified. Anatomical segments, normal and tumor tissue of treated vertebrae were segmented for volumetric analyses. Predictive factors for VCF were identified by logistic regression., Results: Median clinical and radiological FU for all patients was 16.2 months (range, 0-68.2) and 7.8 months (range, 0-66.9), respectively. Local metastasis control was observed in 82% of lesions at last imaging FU. Post-SBRT VCF occurred in 21 lesions (34.4%): 16.4% showed a progressive VCF, while a new VCF occurred in 18.0%. 3/56 (5.4%) patients developed painful VCF defined as pain increase by ≥2 on the visual analogue scale (VAS) and 2 (3.6%) patients required surgical stabilization. Pre-SBRT VCF, localization in the thoracic spine, Bilsky score >0, SINS score, pre-SBRT osteolytic volume and metastatic vertebral body (VB) involvement were predictive factors for VCF on univariate analysis. Relative VB involvement, osteolytic volume and pre-SBRT VCF remained in the multivariate logistic regression model that had AUC = 0.930, 83.3% sensitivity and 96.6% specificity., Conclusion: Spine SBRT resulted in favorable long-term pain and local metastasis control. Despite post-SBRT VCF being observed after one third of treatments, this was symptomatic in only 5% of patients. Predictive factors for developing VCF were identified which could contribute to better selection of patients for spine SBRT., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2019
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49. Problems associated with a highly artificial ketogenic diet: Letter to the Editor Re: van der Louw EJTM, Olieman JF, van den Bemt PMLA, et al . 'Ketogenic diet treatment as adjuvant to standard treatment of glioblastoma multiforme: a feasibility and safety study'.
- Author
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Klement RJ, Sweeney RA, Gross EC, and Champ CE
- Abstract
Competing Interests: Conflict of interest statement: The authors declare that there is no conflict of interest.
- Published
- 2019
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50. The Impact of Serum Glucose in the Treatment of Locoregionally Advanced Pancreatic Cancer.
- Author
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Iarrobino NA, Gill BS, Klement RJ, Bernard ME, and Champ CE
- Subjects
- Adenocarcinoma pathology, Adult, Aged, Aged, 80 and over, Combined Modality Therapy, Female, Follow-Up Studies, Humans, Male, Middle Aged, Pancreatic Neoplasms pathology, Prognosis, Retrospective Studies, Survival Rate, Adenocarcinoma blood, Adenocarcinoma therapy, Blood Glucose analysis, Pancreatic Neoplasms blood, Pancreatic Neoplasms therapy
- Abstract
Introduction: Studies have consistently identified an increased risk of pancreatic cancer in diabetics, yet the role hyperglycemia may play in predicting prognosis is less clear. This work aims to evaluate the impact of glycemic state and antidiabetics on outcomes after systemic and local treatment for locoregionally advanced pancreatic cancer., Materials and Methods: This retrospective study consisted of 303 patients with newly diagnosed advanced-stage pancreatic cancer treated from 2004 to 2014. Kaplan-Meier survival analysis method was used to estimate time to event for overall survival, distant metastasis, and locoregional control. Blood glucose values (n=8599) were assessed both as continuous and categorical variables in univariate and multivariable Cox proportional hazard regression models to estimate hazard ratios (HRs) and identify independent prognostic factors. A 6-month conditional landmark analysis excluding patients with <6 months follow-up or survival was conducted., Results: Median follow-up and survival was 18.1 and 18.4 months, respectively. On univariate analysis, maximum pretreatment glucose value was associated with reduced overall survival (HR 1.005, P=0.023) and locoregional control (HR 1.001, P=0.001). A pretreatment glucose value ≥200 mg/dL was associated with increased mortality in multivariable analysis (adjusted HR 1.01, P=0.015). After conditional analysis, glucose ≥200 mg/dL before local treatment was associated with reduced overall survival (adjusted HR 1.562; 95% confidence interval [CI], 1.16-2.11; P=0.003)., Conclusions: Elevated blood glucose before treatment of locoregionally advanced pancreatic cancer was associated with poorer outcomes. These findings should be incorporated in future clinical trial design.
- Published
- 2019
- Full Text
- View/download PDF
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