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The TKI WoZ VortexLoads project consortium has made a great contribution to more accurate wind turbine design load calculations, paving the way for further reductions in the cost of wind energy. The previously observed reduction in fatigue loading using vortex-wake models instead of the Blade Element Momentum method has been confirmed by using CFD simulations from IAG University of Stuttgart. New light has been shed on the cause for the observed differences and several model improvements have been developed, both to reduce the computational effort and improve robustness of vortex wake simulations (making these ready for application to certification load calculations) as well as to make BEM models more accurate. The improved modelling and the corresponding aerodynamic load reduction have a potential to reduce blade mass and/or further upscaling of the blades leading to a reduction in LCOE.

Within the framework of the TKI WoZ VortexLoads project, CFD simulations were carried out to verify the earlier observed differences in dynamic loading and the resultant fatigue equivalents between BEM and vortex wake codes in turbulent inflow. Hereto a ’numerical’ wind tunnel was set-up subjecting a rigid (or non-flexible) version of the AVATAR 10MW wind turbine model, which can be considered as a reference for the present turbine size. Firstly comparisons in uniform, constant inflow conditions provided a good agreement between all code types, which is a prerequisite for a consistent comparison in more challenging inflow conditions. Sheared inflow conditions demonstrated a difference in the cyclic loading amplitude between BEM and vortex / CFD models. A parameter variation study revealed this difference to scale with the magnitude of the axial induction factor. Turbulent inflow simulations were carried out to verify the influence of turbulence length scale, turbulence intensity and thrust coefficient on the observed differences between the codes.

Fragestellung: Bei zunehmender Inzidenz von solitären Wirbelkörpermetastasen unterschiedlicher Entitäten ist die kombinierte Kyphoplastie mit intraoperativer Radiatio (Kypho-IORT) eine Möglichkeit, nicht nur histo-pathologische Informationen zu erhalten, sondern Schmerzen nachhaltig[zum vollständigen Text gelangen Sie über die oben angegebene URL], Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2018)

Objective: Brain metastases occur in up to 40% of all patients diagnosed with systemic cancer. Without adjuvant radiotherapy after resection of space occupying lesions local recurrence rates are high. That is why guidelines recommend a cavity boosting with x-rays. External beam radiotherapy can[for full text, please go to the a.m. URL], 68. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), 7. Joint Meeting mit der Society of British Neurological Surgeons (SBNS)

Fragestellung: Die IORT hat in den letzten 3 Dekaden starke Evidenz für ein breites Spektrum von klinischen Anwendungen vom Glioblastom, über das Mamma-Karzinom und die Colo-Rectale Krebsarten erbracht. Die erste Kypho-IORT erfolgte 2009. Sie ist ein einzeitiges MIS-Verfahren zur lokalen[zum vollständigen Text gelangen Sie über die oben angegebene URL], Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2016)

Due to the potentially periodic collimator dynamic in volumetric modulated arc therapy (VMAT) dose deliveries with the sweeping-window arc therapy (SWAT) technique, additional manifestations of dosimetric deviations in the presence of intrafractional motion may occur. With a fast multileaf collimator (MLC), and a flattening filter free dose delivery, treatment times close to 60 s per fraction are clinical reality. For these treatment sequences, the human breathing period can be close to the collimator sweeping period. Compared to a random arrangement of the segments, this will cause a further degradation of the dose homogeneity.Fifty VMAT sequences of potentially moving target volumes were delivered on a two dimensional ionization chamber array. In order to detect interplay effects along all three coordinate axes, time resolved measurements were performed twice--with the detector aligned in vertical (V) or horizontal (H) orientation. All dose matrices were then moved within a simulation software by a time-dependent motion vector. The minimum relative equivalent uniform dose EUDr,m for all breathing starting phases was determined for each amplitude and period. Furthermore, an estimation of periods with minimum EUD was performed. Additionally, LINAC logfiles were recorded during plan delivery. The MLC, jaw, gantry angle, and monitor unit settings were continuously saved and used to calculate the correlation coefficient between the target motion and the dose weighed collimator motion component for each direction (CC, LR, AP) separately.The resulting EUDr,m were EUDr,m(CCV) = (98.3 ± 0.6)%, EUDr,m(CCH) = (98.6 ± 0.5)%, EUDr,m(APV) = (97.7 ± 0.9)%, and EUDr,m(LRH) = (97.8 ± 0.9)%. The overall minimum relative EUD observed for 360(∘) arc midventilation treatments was 94.6%. The treatment plan with the shortest period and a minimum relative EUD of less than 97% was found at T = 6.1 s. For a partial 120(∘) arc, an EUDr,m = 92.0% was found. In all cases, a correlation coefficient above 0.5 corresponded to a minimum in EUD.With the advent of fast VMAT delivery techniques, nonrobust treatment sequences for human breathing patterns can be generated. These sequences are characterized by a large correlation coefficient between a target motion component and the corresponding collimator dynamic. By iteratively decreasing the maximum allowed dose rate, a low correlation coefficient and consequentially a robust treatment sequence are ensured.

BACKGROUND AND PURPOSE: Application of ionizing radiation for the purpose of medical research in Germany needs to be approved by the national authority for radiation protection (Bundesamt für Strahlenschutz, BfS). For studies in the field of radiation oncology, differentiation between use of radiation for "medical care (Heilkunde)" versus "medical research" frequently leads to contradictions. The aim of this article is to provide principle investigators, individuals, and institutions involved in the process, as well as institutional review or ethics committees, with the necessary information for this assessment. Information on the legal frame and the approval procedures are also provided. METHODS: A workshop was co-organized by the German Society for Radiation Oncology (DEGRO), the Working Party for Radiation Oncology (ARO) of the German Cancer Society (DKG), the German Society for Medical Physics (DGMP), and the German Cancer Consortium (DKTK) in October 2013. This paper summarizes the results of the workshop and the follow-up discussions between the organizers and the BfS. RESULTS: Differentiating between "Heilkunde" which does not need to be approved by the BfS and "medical research" is whether the specific application of radiation (beam quality, dose, schedule, target volume, etc.) is a clinically established and recognized procedure. This must be answered by the qualified physician(s) ("fachkundiger Arzt" according to German radiation protection law) in charge of the study and the treatments of the patients within the study, taking into consideration of the best available evidence from clinical studies, guidelines and consensus papers. Among the important parameters for assessment are indication, total dose, and fractionation. Radiation treatments applied outside clinical trials do not require approval by the BfS, even if they are applied within a randomized or nonrandomized clinical trial. The decision-making by the "fachkundigem Arzt" may be supported on request by an opinion given by the DEGRO Expert Committee for clinical trials. CONCLUSION: An important aim for promoting clinical research and patient care in radiation oncology is to further professionalize planning and implementation of clinical trials in this field. Correct assessment, at an early stage, whether a trial needs to be approved by the BfS may reduce unneccesary costs and reduce the time needed for the approval procedure for those trials which need to be assessed by the BfS.

The Intensity Modulated Radiation Therapy (IMRT) together with Image Guided Radiation Therapy (IGRT) improves radiation therapy for head and neck cancer. On the one hand tumors can be better covered with radiation dose and on the other hand normal tissue can be better preserved. Carefully applied this leads to the same tumor control rate with reduced toxicity compared with conventional radiation therapy. Respective to the addition of systemic therapy to irradiation therapy, platinum based radiochemotherapy remains the standard of care and there are first indications, that at least in the primary treatment of head and neck cancer the addition of Cetuximab to a cisplatin-based radiochemotherapy did not improve outcome., GMS Current Topics in Otorhinolaryngology - Head and Neck Surgery; 11:Doc02; ISSN 1865-1011

Einleitung: Die Kypho-IORT ist eine neu-entwickelte und 2009 klinisch erstangewendete Methode um Metastasen in Wirbelkörpern(WK) einzeitig zu bestrahlen und die Stabilität wieder herzustellen [ref:1]. Die minimalinvasive perkutane Methode ist mit einer geringen OP-Morbidität[for full text, please go to the a.m. URL], 130. Kongress der Deutschen Gesellschaft für Chirurgie

In early stage non-small cell lung cancer (NSCLC) definitive radiation therapy is an appropriate alternative to surgery. Recent studies show, that in such patients hypofractionation schedules (for example 3 times 18 Gy or 5 times 12 Gy), can be safely applied, without causing severe toxicities and achieving high local control rates of up to 90% and more. In the last couple of years a lot of knowledge about the cancer biology, technical aspects, clinical outcomes and toxicities has been accumulated from different clinical trials. The purpose of this review is to summarize recent outcomes and developments in stereotactic radiation therapy for patients with early stage NSCLC.

Radiotherapy technology has improved rapidly over the past two decades. New imaging modalities, such as positron emission (computed) tomography (PET, PET-CT) and high-resolution morphological and functional magnetic resonance imaging (MRI) have been introduced into the treatment planning process. Image-guided radiation therapy (IGRT) with 3D soft tissue depiction directly imaging target and normal structures, is currently replacing patient positioning based on patient surface markers, frame-based intracranial and extracranial stereotactic treatment and partially also 2D field verification methods. On-line 3D soft tissue-based position correction unlocked the full potential of new delivery techniques, such as intensity-modulated radiotherapy, by safely delivering highly conformal dose distributions that facilitate dose escalation and hypofractionation. These strategies have already resulted in better clinical outcomes, e.g. in prostate and lung cancer and are expected to further improve radiotherapy results.

Einleitung: Das lokal fortgeschrittene Rektumkarzinom wird gemäss Richtlinien neoadjuvant vorbehandelt. Während die Vorteile bezüglich des Lokalrezidivs unbestritten sind, sind die Vorteile bezüglich des Überlebens nur für Subgruppen mit komplettem Ansprechen erzielbar.[for full text, please go to the a.m. URL], 129. Kongress der Deutschen Gesellschaft für Chirurgie

Treatment techniques of increasing complexity such as dynamic/rotational techniques mandate digital management and increasingly image guidance. This constantly increases requirements for image management and archiving. This article discusses the current status of these requirements and will present potential image administration strategies.Fundamentals of image administration and storage/archiving are presented (DICOM Standard, radiotherapy-specific issues) along the typical patient pathway (demographic data, radiotherapy treatment planning, signatures/approval of plan and image data, archiving of plan and image data). Different strategies for image management are presented (archiving centered on individual application vs. integral approach with central archiving in a DICOM-RT-PACS governed by a radiation oncology information system (ROCIS)). Infrastructural requirements depending on the amount of image data generated in the department are discussed.Application-centered image management provides access to image data including all relevant RT-specific elements. This approach, however, is not migration-safe, requires significant administrative work to ensure a redundancy level that protects against data loss and does not provide datasets that are linked to respective therapeutic interventions. Therefore, centralized image management and archiving that links images to patients and individual steps in the treatment pathway within a standardized DICOM(-RT) environment is preferable despite occasional problems with visualization of specific data elements.

Pencil-beam (PB) based dose calculation for treatment planning is limited by inaccuracies in regions of tissue inhomogeneities, particularly in situations with lateral electron disequilibrium as is present at tissue/lung interfaces. To overcome these limitations, a new "lateral disequilibrium inclusive" (LDI) PB based calculation algorithm was introduced. In this study, the authors evaluated the accuracy of the new model by film and ionization chamber measurements and Monte Carlo simulations.To validate the performance of the new LDI algorithm implemented in Corvus 09, eight test plans were generated on inhomogeneous thorax and pelvis phantoms. In addition, three plans were calculated with a simple effective path length (EPL) algorithm on the inhomogeneous thorax phantom. To simulate homogeneous tissues, four test plans were evaluated in homogeneous phantoms (homogeneous dose calculation).The mean pixel pass rates and standard deviations of the gamma 4%/4 mm test for the film measurements were (96 +/- 3)% for the plans calculated with LDI, (70 +/- 5)% for the plans calculated with EPL, and (99 +/- 1)% for the homogeneous plans. Ionization chamber measurements and Monte Carlo simulations confirmed the high accuracy of the new algorithm (dose deviationsor = 4%; gamma 3%/3 mmor = 96%).LDI represents an accurate and fast dose calculation algorithm for treatment planning.

Prolonged administration of temozolomide is widely used in patients with glioblastoma; whereas the treatment of anaplastic glioma differs between neurooncological centres. The safety, feasibility and efficacy of prolonged temozolomide administration in patients with anaplastic gliomas was evaluated.Forty-two patients with primary, recurrent or secondary anaplastic glioma were retrospectively analysed for the course of their disease. Treatment mostly consisted of surgery, followed by radiotherapy with concomitant and adjuvant temozolomide. In five patients with recurrence of primary anaplastic glioma, chemotherapy was initiated without previous surgery. Temozolomide was administered until evidence of tumour recurrence, appearance of serious side-effects or patients' wish to finish chemotherapy.The median overall survival (OS) was 39 months with a median cycle number of 7.5 (1-42). Treatment with temozolomide was stopped in 12 patients due to side-effects in general, whereas in only three patients (7.1%) treatment had to be discontinued due to haematological side-effects. There was no evidence of treatment related infections or grade IV toxicity. Extent of surgery had a significant influence on OS in anaplastic gliomas, the number of adjuvant temozolomide cycles showed a positive influence as well on time to progression (TTP) and OS.Prolonged administration of adjuvant temozolomide is safe and can be favorable for patients with anaplastic gliomas.

Fragestellung: Skelettmetastasen stellen ein zunehmendes Problem dar, auf Grund von gesteigerter Lebenserwartung durch verbesserte Therapiemethoden. Die Wirbelsäule ist mit bis zu 70% die Hauptmanifestation. Die Ballonkyphoplastie ist ein mittlerweile etabliertes gering-invasives Verfahren[for full text, please go to the a.m. URL], Deutscher Kongress für Orthopädie und Unfallchirurgie; 74. Jahrestagung der Deutschen Gesellschaft für Unfallchirurgie, 96. Tagung der Deutschen Gesellschaft für Orthopädie und Orthopädische Chirurgie, 51. Tagung des Berufsverbandes der Fachärzte für Orthopädie

Recent data suggest that a radiosurgery boost treatment for up to three brain metastases in addition to whole brain radiotherapy (WBRT) is beneficial. Sequential treatment of multiple metastatic lesions is time-consuming and optimal normal tissue sparing is not trivial for larger metastases when separate plans are created and are only superimposed afterwards. Sequential Tomotherapy (see image I) with noncoplanar arcs and Multi-field IMRT may streamline the process and enable easy simultaneous treatment. We compared plans for 2-3 intracerebral targets calculated with Intensity Modulated Radiotherapy (IMRT) based on treatment with MLC or sequential Tomotherapy using the Peacock-System (see image II). Treatment time was not to exceed 90 min on a linac with standard dose rate. MIMiC plans without treatment-time restrictions were created as a benchmark.Calculations are based on a Siemens KD2 linac with a dose rate of 200 MU/min. Step-and-Shoot IMRT is performed with a standard MLC (2 x 29 leaves, 1 cm), serial Tomotherapy with the Multivane-Collimator MIMiC (NOMOS Inc. USA) (see image II). Treatment plans are created with Corvus 5.0. To create plans with good conformity we chose a noncoplanar beam- and arc geometry for each approach (IMRT 4-, MIMiC 5-couch angles). The benchmark MIMiC plans with maximally steep dose gradients had 9 couch angles. For plan comparison reasons, 10 Gy were prescribed to 90% of the PTV. Steepness of dose gradients, homogeneity and conformity were assessed by the following parameters: Volume encompassed by certain isodoses outside the target as well as homogeneity and conformity as indicated by Homogeneity- and Conformity-Index.Plans without treatment-time restrictions had slightest dose to organ at risk (OAR), normal tissue and least Conformity-index. MIMiC- and MLC-IMRT based plans can be treated within the intended period of 90 min, all plans met the required dose (see Table 2). MLC based plans resulted in higher dose to organs at risk (OAR) (see table 1) and dose to tissue outside the targets (see table 3), as indicated by a higher CI (see image III). The HI was similar for all calculated plans (see image IV).When treatment plans resulting in a similar treatment time were compared, serial Tomotherapy showed minor advantages over MLC based IMRT with regard to conformity, OAR sparing, and steepness of dose gradients. Both methods are inferior to serial Tomotherapy with ideal plan quality disregarding treatment efficiency. Treating multiple metastases in less than 1 h would therefore be possible on a LINAC with high dose rate and bidirectional rotation with minor compromises on gradient steepness.

Postoperative radiotherapy after breast cancer surgery effectively reduces local relapses. A survival benefit after breast conservation, however, has only been proven recently which was in part due to excessive cardiac mortality of patients who had been treated with radiotherapy in the past.The literature on postoperative radiotherapy for breast cancer was reviewed with regard to cardiac toxicity as the basis for hypothesis generation.From numerous publications on cardiac toxicity of breast cancer radiotherapy, the following pattern emerges: in series where a high radiation dose was applied to a significant percentage of the heart (postmastectomy and postlumpectomy series) cardiac toxicity/mortality was increased versus a nonexposed cohort or for left over right disease. If, however, a relevant exposure of cardiac muscle could be more or less excluded based on the technique used (mainly more recent postlumpectomy radiotherapy), no cardiac toxicity was observed. Series for which individual dose exposure varied or could not be clarified also came to varying conclusions. Also due to retrospectively unclear dose distributions, an exact quantification of tolerance doses/effects of different geographic dose distribution patterns could not be performed to date. A particularly difficult question to answer is the threshold volume for clinically relevant cardiotoxicity with tangential radiotherapy at prescription doses. As a consequence, this precludes an estimate in which situations multifield intensity-modulated radiotherapy (IMRT) with its characteristic dose distribution pattern of a larger volume exposed to intermediate doses and higher mean/median heart doses (as shown in Figure 1) might be preferable.This review updates the database on cardiac toxicity of breast cancer radiotherapy with special emphasis regarding the issues related to the clinical use of IMRT. Multifield IMRT may reduce the cardiac risk for a small subset of patients at excessive risk with conventional tangential radiotherapy due to unfavorable thoracic geometry, for whom partial-breast radiotherapy is not an option. Due to further concern about the effects of intermediate doses to larger heart volumes, potentially increased contralateral cancer risk and the long latency of clinically apparent toxicity, the introduction of breast IMRT should be closely followed. Accompanying functional studies may have the potential to detect cardiac toxicity at an earlier time.

Intensity modulated radiotherapy (IMRT) has improved the capability to apply geometrically individualised high radiotherapy doses to the prostate bed, prostate and seminal vesicles. A high risk of geometrical miss with conformal methods, however, has been documented for mobile targets such as the prostate. Modern, non-invasive localisation techniques are therefore mandatory to further optimise conformal radiotherapy for prostate cancer. This review summarises technological advances related to "image-guided radiotherapy" (IGRT) which will further improve target positioning in prostate cancer radiotherapy.

The purpose of this work is to give practical guidelines for radiotherapy of locally advanced, inflammatory and metastatic breast cancer at first presentation.A comprehensive survey of the literature using the search phrases "locally advanced breast cancer", "inflammatory breast cancer", "breast cancer and synchronous metastases", "de novo stage IV and breast cancer", and "metastatic breast cancer" and "at first presentation" restricted to "clinical trials", "randomized trials", "meta-analysis", "systematic review", and "guideline" was performed and supplemented by using references of the respective publications. Based on the German interdisciplinary S3 guidelines, updated in 2012, this publication addresses indications, sequence to other therapies, target volumes, dose, and fractionation of radiotherapy.International and national guidelines are in agreement that locally advanced, at least if regarded primarily unresectable and inflammatory breast cancer should receive neoadjuvant systemic therapy first, followed by surgery and radiotherapy. If surgery is not amenable after systemic therapy, radiotherapy is the treatment of choice followed by surgery, if possible. Surgery and radiotherapy should be administered independent of response to neoadjuvant systemic treatment. In patients with a de novo diagnosis of breast cancer with synchronous distant metastases, surgery and radiotherapy result in considerably better locoregional tumor control. An improvement in survival has not been consistently proven, but may exist in subgroups of patients.Radiotherapy is an important part in the treatment of locally advanced and inflammatory breast cancer that should be given to all patients regardless to the intensity and effect of neoadjuvant systemic treatment and the extent of surgery. Locoregional radiotherapy in patients with primarily distant metastatic disease should be prescribed on an individual basis.