Proton arc therapy increases the benefit of proton therapy for oropharyngeal cancer patients in the model based clinic

Background and purpose: In the model-based approach, patients qualify for proton therapy when the reduction in risk of toxicity (ΔNTCP) obtained with IMPT relative to VMAT is larger than predefined thresholds as defined by the Dutch National Indication Protocol (NIPP). Proton arc therapy (PAT) is an emerging technology which has the potential to further decrease NTCPs compared to IMPT. The aim of this study was to investigate the potential impact of PAT on the number of oropharyngeal cancer (OPC) patients that qualify for proton therapy.Materials and methods: A prospective cohort of 223 OPC patients subjected to the model-based selection procedure was investigated. 33 (15%) patients were considered unsuitable for proton treatment before plan comparison. When IMPT was compared to VMAT for the remaining 190 patients, 148 (66%) patients qualified for protons and 42 (19%) patients did not. For these 42 patients treated with VMAT, robust PAT plans were generated.Results: PAT plans provided better or similar target coverage compared to IMPT plans. In the PAT plans, integral dose was significantly reduced by 18% relative to IMPT plans and by 54% relative to VMAT plans. PAT decreased the mean dose to numerous organs-at-risk (OARs), further reducing NTCPs. The ΔNTCP for PAT relative to VMAT passed the NIPP thresholds for 32 out of the 42 patients treated with VMAT, resulting in 180 patients (81%) of the complete cohort qualifying for protons.Conclusion: PAT outperforms IMPT and VMAT, leading to a further reduction of NTCP-values and higher ΔNTCP-values, significantly increasing the percentage of OPC patients selected for proton therapy.</p

Моніторинг розвитку навичок мовлення та аудіювання

Мета цього дослідження є спостереження та аналіз змін якості навичок володіння мовленням і якості володіння навичками аудіювання в процесі навчання. Завдання дослідження полягає у наступному : а) вивчити яким чином сучасні методи моніторингу впливають на поліпшення якості володіння мовленням, б) простежити якісні зміни знань студентів на трьох етапах: стартовому, поточному та підсумковому. Методами моніторингу є анкетування. самостійна робота, тестування

Publication Bias in Laboratory Animal Research: A Survey on Magnitude, Drivers, Consequences and Potential Solutions

Contains fulltext : 109229.pdf (publisher's version ) (Open Access)CONTEXT: Publication bias jeopardizes evidence-based medicine, mainly through biased literature syntheses. Publication bias may also affect laboratory animal research, but evidence is scarce. OBJECTIVES: To assess the opinion of laboratory animal researchers on the magnitude, drivers, consequences and potential solutions for publication bias. And to explore the impact of size of the animals used, seniority of the respondent, working in a for-profit organization and type of research (fundamental, pre-clinical, or both) on those opinions. DESIGN: Internet-based survey. SETTING: All animal laboratories in The Netherlands. PARTICIPANTS: Laboratory animal researchers. MAIN OUTCOME MEASURE(S): Median (interquartile ranges) strengths of beliefs on 5 and 10-point scales (1: totally unimportant to 5 or 10: extremely important). RESULTS: Overall, 454 researchers participated. They considered publication bias a problem in animal research (7 (5 to 8)) and thought that about 50% (32-70) of animal experiments are published. Employees (n = 21) of for-profit organizations estimated that 10% (5 to 50) are published. Lack of statistical significance (4 (4 to 5)), technical problems (4 (3 to 4)), supervisors (4 (3 to 5)) and peer reviewers (4 (3 to 5)) were considered important reasons for non-publication (all on 5-point scales). Respondents thought that mandatory publication of study protocols and results, or the reasons why no results were obtained, may increase scientific progress but expected increased bureaucracy. These opinions did not depend on size of the animal used, seniority of the respondent or type of research. CONCLUSIONS: Non-publication of "negative" results appears to be prevalent in laboratory animal research. If statistical significance is indeed a main driver of publication, the collective literature on animal experimentation will be biased. This will impede the performance of valid literature syntheses. Effective, yet efficient systems should be explored to counteract selective reporting of laboratory animal research

Proposed quality indicators and recommended standard reporting items in performance of EBUS bronchoscopy: An official world association for bronchology and interventional pulmonology expert panel consensus statement

Background: Since their introduction, both linear and radial endobronchial ultrasound (EBUS) have become an integral component of the practice of Pulmonology and Thoracic Oncology. The quality of health care can be measured by comparing the performance of an individual or a health service with an ideal threshold or benchmark. The taskforce sought to evaluate quality indicators in EBUS bronchoscopy based on clinical relevance/importance and on the basis that observed significant variation in outcomes indicates potential for improvement in health care outcomes. Methods: A comprehensive literature review informed the composition of a comprehensive list of candidate quality indicators in EBUS. A multiple-round modified Delphi consensus process was subsequently performed with the aim of reaching consensus over a final list of quality indicators and performance targets for these indicators. Standard reporting items were developed, with a strong preference for items where evidence demonstrates a relationship with quality indicator outcomes. Results: Twelve quality Indicators are proposed, with performance targets supported by evidence from the literature. Standardized reporting items for both radial and linear EBUS are recommended, with evidence supporting their utility in assessing procedural outcomes presented. Conclusion: This statement is intended to provide a framework for individual proceduralists to assess the quality of EBUS they provide their patients through the identification of clinically relevant, feasible quality measures. Emphasis is placed on outcome measures, with a preference for consistent terminology to allow communication and benchmarking between centres

Head and neck IMPT probabilistic dose accumulation:Feasibility of a 2 mm setup uncertainty setting

OBJECTIVE: To establish optimal robust optimization uncertainty settings for clinical head and neck cancer (HNC) patients undergoing 3D image-guided pencil beam scanning (PBS) proton therapy. METHODS: We analyzed ten consecutive HNC patients treated with 70 and 54.25 GyRBE to the primary and prophylactic clinical target volumes (CTV) respectively using intensity-modulated proton therapy (IMPT). Clinical plans were generated using robust optimization with 5 mm/3% setup/range uncertainties (RayStation v6.1). Additional plans were created for 4, 3, 2 and 1 mm setup and 3% range uncertainty and for 3 mm setup and 3%, 2% and 1% range uncertainty. Systematic and random error distributions were determined for setup and range uncertainties based on our quality assurance program. From these, 25 treatment scenarios were sampled for each plan, each consisting of a systematic setup and range error and daily random setup errors. Fraction doses were calculated on the weekly verification CT closest to the date of treatment as this was considered representative of the daily patient anatomy. RESULTS: Plans with a 2 mm/3% setup/range uncertainty setting adequately covered the primary and prophylactic CTV (V95≥ 99% in 98.8% and 90.8% of the treatment scenarios respectively). The average organ-at-risk dose decreased with 1.1 GyRBE/mm setup uncertainty reduction and 0.5 GyRBE/1% range uncertainty reduction. Normal tissue complication probabilities decreased by 2.0%/mm setup uncertainty reduction and by 0.9%/1% range uncertainty reduction. CONCLUSION: The results of this study indicate that margin reduction below 3 mm/3% is possible but requires a larger cohort to substantiate clinical introduction

Practical robustness evaluation in radiotherapy - A photon and proton-proof alternative to PTV-based plan evaluation

Background and purpose: A planning target volume (PTV) in photon treatments aims to ensure that the clinical target volume (CTV) receives adequate dose despite treatment uncertainties. The underlying static dose cloud approximation (the assumption that the dose distribution is invariant to errors) is problematic in intensity modulated proton treatments where range errors should be taken into account as well. The purpose of this work is to introduce a robustness evaluation method that is applicable to photon and proton treatments and is consistent with (historic) PTV-based treatment plan evaluations. Materials and methods: The limitation of the static dose cloud approximation was solved in a multi-scenario simulation by explicitly calculating doses for various treatment scenarios that describe possible errors in the treatment course. Setup errors were the same as the CTV-PTV margin and the underlying theory of 3D probability density distributions was extended to 4D to include range errors, maintaining a 90% confidence level. Scenario dose distributions were reduced to voxel-wise minimum and maximum dose distributions; the first to evaluate CTV coverage and the second for hot spots. Acceptance criteria for CTV D98 and D2 were calibrated against PTV-based criteria from historic photon treatment plans. Results: CTV D98 in worst case scenario dose and voxel-wise minimum dose showed a very strong correlation with scenario average D98 (R-2 > 0.99). The voxel-wise minimum dose visualised CTV dose conformity and coverage in 3D in agreement with PTV-based evaluation in photon therapy. Criteria for CTV D98 and D2 of the voxel-wise minimum and maximum dose showed very strong correlations to PTV D98 and D2 (R-2 > 0.99) and on average needed corrections of -0.9% and +2.3%, respectively. Conclusions: A practical approach to robustness evaluation was provided and clinically implemented for PTV-less photon and proton treatment planning, consistent with PTV evaluations but without its static dose cloud approximation. (C) 2019 The Authors. Published by Elsevier B.V

Identification of Novel Genetic Loci Associated with Thyroid Peroxidase Antibodies and Clinical Thyroid Disease

Peer reviewe

A social media self-evaluation checklist for medical practitioners

Increasing numbers of medical practitioners and medical students are using online social and business-related networking websites such as Facebook, Doc2doc and LinkedIn. These rapidly evolving and growing social media have potential to promote public health by providing powerful instruments for communication and education. However, evidence is emerging from studies, legal cases, and media reports that the use of these new technologies is creating several ethical problems for medical practitioners as well as medical students. Improper online activities may harm not only individual reputations and careers, but also the medical profession as a whole, for example by breach of patient confidentiality, defamation of colleagues and employers, undisclosed conflict of interests that bias the medical practitioner's medical advice, posting of advice/information without an evidence base, and infringement of copyright. We developed a self-evaluation checklist for medical practitioners using social media. The checklist addresses three key elements in the use of social media: personal information and accessibility, connections, and postings. It contains questions specifically formulated to evaluate a medical practitioner's social media profile, to prevent unintended, improper online activities and to promote professional online behaviou

Reporting of Imaging Diagnostic Accuracy Studies With Focus on MRI Subgroup: Adherence to STARD 2015

Purpose: To evaluate adherence of diagnostic accuracy studies in imaging journals to the STAndards for Reporting of Diagnostic accuracy studies (STARD) 2015. The secondary objective was to identify differences in reporting for magnetic resonance imaging (MRI) studies. Materials and Methods: MEDLINE was searched for diagnostic accuracy studies published in imaging journals in 2016. Studies were evaluated for adherence to STARD 2015 (30 items, including expanded imaging specific subitems). Evaluation for differences in STARD adherence based on modality, impact factor, journal STARD adoption, country, subspecialty area, study design, and journal was performed. Results: Adherence (n = 142 studies) was 55% (16.6/30 items, SD = 2.2). Index test description (including imaging-specific subitems) and interpretation were frequently reported (>66% of studies); no important differences in reporting of individual items were identified for studies on MRI. Infrequently reported items ( <33% of studies) included some critical to generalizability (study setting and location) and assessment of bias (blinding of assessor of reference standard). New STARD 2015 items: sample size calculation, protocol reporting, and registration were infrequently reported. Higher impact factor (IF) journals reported more items than lower IF journals (17.2 vs. 16 items; P = 0.001). STARD adopter journals reported more items than nonadopters (17.5 vs. 16.4 items; P = 0.01). Adherence varied between journals (P = 0.003). No variability for study design (P = 0.32), subspecialty area (P = 0.75), country (P = 0.28), or imaging modality (P = 0.80) was identified. Conclusion: Imaging accuracy studies show moderate adherence to STARD 2015, with only minor differences for studies evaluating MRI. This baseline evaluation will guide targeted interventions towards identified deficiencies and help track progress in reportin