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Radiotherapy and Oncology : Journal of... Jul 2023Target delineation in glioblastoma is still a matter of extensive research and debate. This guideline aims to update the existing joint European consensus on delineation...
BACKGROUND AND PURPOSE
Target delineation in glioblastoma is still a matter of extensive research and debate. This guideline aims to update the existing joint European consensus on delineation of the clinical target volume (CTV) in adult glioblastoma patients.
MATERIAL AND METHODS
The ESTRO Guidelines Committee identified 14 European experts in close interaction with the ESTRO clinical committee and EANO who discussed and analysed the body of evidence concerning contemporary glioblastoma target delineation, then took part in a two-step modified Delphi process to address open questions.
RESULTS
Several key issues were identified and are discussed including i) pre-treatment steps and immobilisation, ii) target delineation and the use of standard and novel imaging techniques, and iii) technical aspects of treatment including planning techniques and fractionation. Based on the EORTC recommendation focusing on the resection cavity and residual enhancing regions on T1-sequences with the addition of a reduced 15 mm margin, special situations are presented with corresponding potential adaptations depending on the specific clinical situation.
CONCLUSIONS
The EORTC consensus recommends a single clinical target volume definition based on postoperative contrast-enhanced T1 abnormalities, using isotropic margins without the need to cone down. A PTV margin based on the individual mask system and IGRT procedures available is advised; this should usually be no greater than 3 mm when using IGRT.
Topics: Adult; Humans; Glioblastoma; Radiotherapy Planning, Computer-Assisted; Dose Fractionation, Radiation
PubMed: 37059335
DOI: 10.1016/j.radonc.2023.109663 -
Lung Cancer (Amsterdam, Netherlands) Aug 2023Stereotactic body radiotherapy (SBRT) is an effective and safe modality for early-stage lung cancer and lung metastases. However, tumors in an ultra-central location... (Meta-Analysis)
Meta-Analysis
Stereotactic body radiotherapy for Ultra-Central lung Tumors: A systematic review and Meta-Analysis and International Stereotactic Radiosurgery Society practice guidelines.
BACKGROUND
Stereotactic body radiotherapy (SBRT) is an effective and safe modality for early-stage lung cancer and lung metastases. However, tumors in an ultra-central location pose unique safety considerations. We performed a systematic review and meta-analysis to summarize the current safety and efficacy data and provide practice recommendations on behalf of the International Stereotactic Radiosurgery Society (ISRS).
METHODS
We performed a systematic review using PubMed and EMBASE databases of patients with ultra-central lung tumors treated with SBRT. Studies reporting local control (LC) and/or toxicity were included. Studies with <5 treated lesions, non-English language, re-irradiation, nodal tumors, or mixed outcomes in which ultra-central tumors could not be discerned were excluded. Random-effects meta-analysis was performed for studies reporting relevant endpoints. Meta-regression was conducted to determine the effect of various covariates on the primary outcomes.
RESULTS
602 unique studies were identified of which 27 (one prospective observational, the remainder retrospective) were included, representing 1183 treated targets. All studies defined ultra-central as the planning target volume (PTV) overlapping the proximal bronchial tree (PBT). The most common dose fractionations were 50 Gy/5, 60 Gy/8, and 60 Gy/12 fractions. The pooled 1- and 2-year LC estimates were 92 % and 89 %, respectively. Meta-regression identified biological effective dose (BED10) as a significant predictor of 1-year LC. A total of 109 grade 3-4 toxicity events, with a pooled incidence of 6 %, were reported, most commonly pneumonitis. There were 73 treatment related deaths, with a pooled incidence of 4 %, with the most common being hemoptysis. Anticoagulation, interstitial lung disease, endobronchial tumor, and concomitant targeted therapies were observed risk factors for fatal toxicity events.
CONCLUSION
SBRT for ultra-central lung tumors results in acceptable rates of local control, albeit with risks of severe toxicity. Caution should be taken for appropriate patient selection, consideration of concomitant therapies, and radiotherapy plan design.
Topics: Humans; Lung Neoplasms; Radiosurgery; Retrospective Studies; Lung; Dose Fractionation, Radiation; Observational Studies as Topic
PubMed: 37393758
DOI: 10.1016/j.lungcan.2023.107281 -
Practical Radiation Oncology 2024This guideline provides evidence-based recommendations on appropriate indications and techniques for partial breast irradiation (PBI) for patients with early-stage...
PURPOSE
This guideline provides evidence-based recommendations on appropriate indications and techniques for partial breast irradiation (PBI) for patients with early-stage invasive breast cancer and ductal carcinoma in situ.
METHODS
ASTRO convened a task force to address 4 key questions focused on the appropriate indications and techniques for PBI as an alternative to whole breast irradiation (WBI) to result in similar rates of ipsilateral breast recurrence (IBR) and toxicity outcomes. Also addressed were aspects related to the technical delivery of PBI, including dose-fractionation regimens, target volumes, and treatment parameters for different PBI techniques. The guideline is based on a systematic review provided by the Agency for Healthcare Research and Quality. Recommendations were created using a predefined consensus-building methodology and system for grading evidence quality and recommendation strength.
RESULTS
PBI delivered using 3-dimensional conformal radiation therapy, intensity modulated radiation therapy, multicatheter brachytherapy, and single-entry brachytherapy results in similar IBR as WBI with long-term follow-up. Some patient characteristics and tumor features were underrepresented in the randomized controlled trials, making it difficult to fully define IBR risks for patients with these features. Appropriate dose-fractionation regimens, target volume delineation, and treatment planning parameters for delivery of PBI are outlined. Intraoperative radiation therapy alone is associated with a higher IBR rate compared with WBI. A daily or every-other-day external beam PBI regimen is preferred over twice-daily regimens due to late toxicity concerns.
CONCLUSIONS
Based on published data, the ASTRO task force has proposed recommendations to inform best clinical practices on the use of PBI.
Topics: Female; Humans; Brachytherapy; Breast; Breast Neoplasms; Carcinoma, Intraductal, Noninfiltrating; Radiotherapy, Conformal; United States; Systematic Reviews as Topic
PubMed: 37977261
DOI: 10.1016/j.prro.2023.11.001 -
British Journal For the History of... Mar 2024These volumes conclude a series initiated in 1974, marking almost fifty years of effort by a huge cohort of scholars. This review is thus a valedictory for the whole... (Review)
Review
These volumes conclude a series initiated in 1974, marking almost fifty years of effort by a huge cohort of scholars. This review is thus a valedictory for the whole series as well as an account of what we have learned from the most recent volumes about Darwin's final years (1879-82). The project was begun by Frederick Burckhardt, who shared the editorial role for the early volumes with Sydney Smith and a rolling sequence of assistant editors and advisers who eventually comprised a significant fraction of the leading members of what used to be called the 'Darwin industry'. Smith passed away in 1988 (volume 7 notes his legacy). Burkardt too left this world in 2007 - volume 16, part 1 includes an obituary, but his name has been retained and Cambridge University Press still ask that the series be cited as 'Burkhardt ' Duncan Porter took over for volumes 8-15, again with a sequence of fellow editors and assistants, after which James Secord became head of the project through its final years. The dedications of successive volumes record the efforts of individual scholars who have aided the teams and the involvement of the many institutions and foundations that have leant moral and material support over the years. For those of us with Cambridge connections, the University Library will not seem the same without the presence of the team it supported.
Topics: Biological Evolution; History, 19th Century; History, 20th Century; Serial Publications
PubMed: 38178808
DOI: 10.1017/S0007087423001036 -
Environmental Science & Technology Sep 2023The effects and risks of microplastics correlate with three-dimensional (3D) properties, such as the volume and surface area of the biologically accessible fraction of...
The effects and risks of microplastics correlate with three-dimensional (3D) properties, such as the volume and surface area of the biologically accessible fraction of the diverse particle mixtures as they occur in nature. However, these 3D parameters are difficult to estimate because measurement methods for spectroscopic and visible light image analysis yield data in only two dimensions (2D). The best-existing 2D to 3D conversion models require calibration for each new set of particles, which is labor-intensive. Here we introduce a new model that does not require calibration and compare its performance with existing models, including calibration-based ones. For the evaluation, we developed a new method in which the volumes of environmentally relevant microplastic mixtures are estimated in one go instead of on a cumbersome particle-by-particle basis. With this, the new Barchiesi model can be seen as the most universal. The new model can be implemented in software used for the analysis of infrared spectroscopy and visual light image analysis data and is expected to increase the accuracy of risk assessments based on particle volumes and surface areas as toxicologically relevant metrics.
Topics: Microplastics; Plastics; Benchmarking; Calibration; Light
PubMed: 37683039
DOI: 10.1021/acs.est.3c03620 -
Journal of Cardiovascular Medicine... Aug 2023Age-specific and gender-specific reference values for left ventricular (LV) and right ventricle volumes are available. The prognostic implications of the ratio between...
BACKGROUND
Age-specific and gender-specific reference values for left ventricular (LV) and right ventricle volumes are available. The prognostic implications of the ratio between these volumes in heart failure and preserved ejection fraction (HFpEF) have never been evaluated.
METHODS
We examined all HFpEF outpatients undergoing a cardiac magnetic resonance from 2011 to 2021. The left-to-right ventricular volume ratio (LRVR) was defined as the ratio between the LV and right ventricle end-diastolic volume indexes (LVEDVi/RVEDVi).
RESULTS
Among 159 patients [median age 58 years (interquartile range 49-69), 64% men, LV ejection fraction 60% (54-70%)] the median LRVR was 1.21 (1.07-1.40). Over 3.5 years (1.5-5.0), 23 patients (15%) experienced all-cause death or heart failure hospitalization, and 22 (14%) cardiovascular death or heart failure hospitalization. The risk of all-cause death or heart failure hospitalization increased with an LRVR less than 1.0 or at least 1.4. An LRVR less than 1.0 was associated with a higher risk of all-cause death or heart failure hospitalization [hazard ratio 5.95, 95% confidence interval (CI) 1.67-21.28; P = 0.006] and cardiovascular death or heart failure hospitalization (hazard ratio 5.68, 95% CI 1.58-20.35; P = 0.008) as compared with LRVR 1.0-1.3. Furthermore, an LRVR at least 1.4 was associated with a higher risk of all-cause death or heart failure hospitalization (hazard ratio 4.10, 95% CI 1.58-10.61; P = 0.004) and cardiovascular death or heart failure hospitalization (hazard ratio 3.71, 95% CI 1.41-9.79; P = 0.008) as compared with LRVR 1.0-1.3. These results were confirmed in patients without dilation of either ventricle.
CONCLUSION
LRVR values less than 1.0 or at least 1.4 are associated with worse outcomes in HFpEF. LRVR may become a valuable tool for risk prediction in HFpEF.
Topics: Male; Humans; Middle Aged; Female; Heart Failure; Stroke Volume; Heart Ventricles; Ventricular Function, Left; Prognosis; Hospitalization
PubMed: 37409600
DOI: 10.2459/JCM.0000000000001500 -
Small (Weinheim An Der Bergstrasse,... Oct 2023Void volume fraction (VVF) is a global measurement frequently used to characterize the void space of granular scaffolds, yet there is no gold standard by which to...
Void volume fraction (VVF) is a global measurement frequently used to characterize the void space of granular scaffolds, yet there is no gold standard by which to measure VVF in practice. To study the relationship between VVF and particles of varying size, form, and composition, a library of 3D simulated scaffolds is used. Results reveal that relative to particle count, VVF is a less predictable metric across replicate scaffolds. Simulated scaffolds are used to explores the relationship between microscope magnification and VVF, and recommendations are offered for optimizing the accuracy of approximating VVF using 2D microscope images. Lastly, VVF of hydrogel granular scaffolds is measured while varying four input parameters: image quality, magnification, analysis software, and intensity threshold. Results show that VVF is highly sensitive to these parameters. Overall, random packing produces variation in VVF among granular scaffolds comprising the same particle populations. Furthermore, while VVF is used to compare the porosity of granular materials within a study, VVF is a less reliable metric across studies that use different input parameters. VVF, a global measurement, cannot describe the dimensions of porosity within granular scaffolds, and the work supports the notion that more descriptors are necessary to sufficiently characterize void space.
PubMed: 37267936
DOI: 10.1002/smll.202303466 -
Journal of Neuro-oncology Sep 2023Despite aggressive management consisting of surgery, radiation therapy (RT), and systemic therapy given alone or in combination, a significant proportion of patients... (Review)
Review
Despite aggressive management consisting of surgery, radiation therapy (RT), and systemic therapy given alone or in combination, a significant proportion of patients with brain tumors will experience tumor recurrence. For these patients, no standard of care exists and management of either primary or metastatic recurrent tumors remains challenging.Advances in imaging and RT technology have enabled more precise tumor localization and dose delivery, leading to a reduction in the volume of health brain tissue exposed to high radiation doses. Radiation techniques have evolved from three-dimensional (3-D) conformal RT to the development of sophisticated techniques, including intensity modulated radiation therapy (IMRT), volumetric arc therapy (VMAT), and stereotactic techniques, either stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT). Several studies have suggested that a second course of RT is a feasible treatment option in patients with a recurrent tumor; however, survival benefit and treatment related toxicity of reirradiation, given alone or in combination with other focal or systemic therapies, remain a controversial issue.We provide a critical overview of the current clinical status and technical challenges of reirradiation in patients with both recurrent primary brain tumors, such as gliomas, ependymomas, medulloblastomas, and meningiomas, and brain metastases. Relevant clinical questions such as the appropriate radiation technique and patient selection, the optimal radiation dose and fractionation, tolerance of the brain to a second course of RT, and the risk of adverse radiation effects have been critically discussed.
Topics: Humans; Re-Irradiation; Neoplasm Recurrence, Local; Brain Neoplasms; Radiotherapy, Conformal; Radiosurgery; Cerebellar Neoplasms
PubMed: 37624529
DOI: 10.1007/s11060-023-04407-2