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To evaluate the outcome of partial breast reirradiation (re-PBI) with intensity modulated radiation therapy using a hypofractionated scheme for breast cancer (BC) local relapse (LR) operated on with repeat breast-conservative surgery. Intensity modulated radiation therapy-based re-PBI was performed using either helical or step-and-shoot modality to deliver 37.05 Gy in 13 fractions in 2.5 weeks. Cumulative incidence of second LR, toxicity, disease-free survival (DFS), BC-specific survival, and overall survival were evaluated. Between May 2012 and May 2021, 70 patients had re-PBI. The median follow-up (FU) was 6.3 years (quartiles 1-3, 4.0-8.1.). The median age at first LR was 62 years. The median primary BC first LR interval was 12.4 years (range, 1.6-26.7 years). Luminal A-like first LR accounted for 41% of the cases, and the median size was 0.8 cm. During FU, 18 (26%) patients showed a subsequent event: 3 second LRs (corresponding to an 8-year cumulative rate of 4%), 3 regional nodal recurrences, 7 distant metastases, and 5 other primary tumors. At 8 years, DFS, BC-specific survival, and overall survival were 76%, 90%, and 90%, respectively. At multivariate analysis, grade 3 and extensive intraductal components were independent predictors for DFS. For 51 and 46 patients, chronic toxicity and cosmesis were evaluated, respectively: 4% had grade 3 fibrosis, and cosmesis was deemed good/excellent in just >60% of the cases. Re-PBI after repeat breast-conservative surgery represents a feasible alternative to mastectomy with regard to local control, showing an acceptable toxicity profile. A long-term FU is crucial to better understand the pattern of relapse and consolidate the position of re-PBI in clinical practice. [ABSTRACT FROM AUTHOR]

• Patients with HER2-positive MBC have a significant risk developing BrM. • Experts created statements regarding BrM prevention in HER2-positive MBC. • Using a modified Delphi process, experts reached consensus on 34 statements. • Statements covered definitions, screening, treatment efficacy and prevention of BrM. • These statements can provide guidance in daily practice and clinical trial design. Patients with HER2-positive breast cancer have a significant risk of developing brain metastases (BrM), which have detrimental effects on survival outcomes and quality of life. Although there are several systemic treatment options available that may delay the appearance of BrM and secondary progression of previously treated BrM, there are still substantial unmet needs for this patient population and primary prevention remains elusive. A group of experts created consensus statements, through a modified Delphi process, to bridge the gap between current unmet needs, available evidence, and international guidelines. The steering committee reviewed all relevant literature and formed research questions to be answered by the subsequent consensus statements. In total, 61 contributors provided feedback on the consensus statements, with 34 statements reaching agreement out of the 55 statements that were voted on altogether. Statements with consensus aimed to define BrM primary and secondary prevention, screening procedures, assessment of symptoms, treatment efficacy, and preventing the occurrence and progression of BrM, while acknowledging the possibilities and limitations in daily clinical practice. Some statements did not reach agreement for a variety of reasons, mostly due to lack of evidence. The consensus statements outlined in this publication provide a point of reference for daily clinical practice and can act as recommendations for clinical trial procedures and future guidelines. [ABSTRACT FROM AUTHOR]

• The Cyberknife cardiac treatments by tracking a single marker were investigated. • The displacement during the tracking and needed planning margins were studied. • The dosimetric accuracy of the treatment was verified. • The results show that the margin increases with the lesion's distance from the lead. • The tracking with a single marker is feasible considering residual planning margins. Within the STRA-MI-VT phase Ib/II trial (NCT04066517), the aim of this phantom study was to explore the feasibility of Cyberknife treatments on cardiac lesions by tracking as a single marker the lead tip of an implantable cardioverter defibrillator. The residual displacement of the lesion during the tracking was studied, planning margins were found and the dosimetric accuracy of the treatment was checked. A lead was inserted into a phantom (EasyCube phantom, Sun Nuclear Co, USA) and then placed on the translating ExacTrac Gating System (BrainLAB AG, Germany). The phantom was rotated, a virtual lesion was identified and its displacement during the tracking was studied. Two plans were compared, calculated on the unrotated volume and on the envelope of the unrotated and the rotated volumes. The plans were delivered using the Cyberknife System (Accuray Inc, USA) and their dosimetric accuracy verified by gamma analysis with gafchromic films. The residual margin increases enhancing the distance between the lead and the lesion. It is 4 mm for distance 0 cm and 5 mm for distance 5 cm. The coverage is reduced by 3.8% (interquartile range 2.5%–4.7%) when the dose is prescribed on the unrotated volume. All treatment plans are accurate and 3% 3 mm gamma analysis results are greater than 94%. Results showed that tracking with a single marker is feasible considering adequate residual planning margins. The volumes could be further reduced by using additional markers, for example by placing them on the patient's skin. [ABSTRACT FROM AUTHOR]

Recently, we are witnessing a growing interest in the study of climate narratives and storylines. These are seen as critical tools both for improving shared understandings involving different stakeholders (including scientists from different disciplines) and guiding initiatives for transformative adaptation actions and decision making. This paper approaches the storylines about a severe drought event that took place in southeastern South America (SESA) in 2008/2009 from an interdisciplinary dialogue between climatologists and anthropologists. This approach responds to the need for a more robust understanding of the event and the responses adopted locally, i.e: not restricted to physical aspects but considering socio-economic and political aspects, with the aim of contributing to the development of socially relevant climatic information for realistic climate risk decision making contexts. In particular it intends to contribute to the decision-making processes of government agencies focused on climate communication and public climate services, such as national and weather services and regional agencies. Considering disciplinary differences, we account for the interpretative polyphony regarding this event, i.e.: what each actor/sector is talking about (for what and to whom they are talking about) when referring to "the drought", and analyze climate storylines as an agonistic field of meanings. This implies recognizing the disputes and contradictions among them, how different storylines promote certain lines of argumentation and meanings to the detriment of others, knowledge gaps, the role of social power relations, socio-political order factors and their impact in terms of the necessary transformations towards an environmentally sustainable and socially just horizon. • Interdisciplinary approach to climate storylines. • Climate storylines as an agonistic field of meanings. • Physical aspects as well as power structure's role in climate storylines. • Socio-political order factors and decision making alternatives. • Transformations towards an environmentally sustainable and socially just horizon. [ABSTRACT FROM AUTHOR]

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• Consensus for the management of PCa recurrence following EBRT is lacking. • Salvage SBRT represents an effective and safe treatment option. • Literature on dosimetric constraints for safe and effective re-irradiation is scarce. • The study provides a useful benchmark for re-irradiation planning. The primary aim of this study is to provide preliminary indications for safe constraints of rectum and bladder in patients re-irradiated with stereotactic body RT (SBRT). Data from patients treated for prostate cancer (PCa) and intraprostatic relapse, from 1998 to 2016, were retrospectively collected. First RT course was delivered with 3D conformal RT techniques, SBRT or volumetric modulated arc therapy (VMAT). All patients underwent re-irradiation with SBRT with heavy hypofractionated schedules. Cumulative dose-volume values to organs at risk (OARs) were computed and possible correlation with developed toxicities was investigated. Twenty-six patients were included. Median age at re-irradiation was 75 years, mean interval between the two RT courses was 5.6 years and the median follow-up was 47.7 months (13.4–114.3 months). After re-irradiation, acute and late G ≥ 2 GU toxicity events were reported in 3 (12%) and 10 (38%) patients, respectively, while late G ≥ 2 GI events were reported in 4 (15%) patients. No acute G ≥ 2 GI side effects were registered. Patients receiving an equivalent uniform dose of the two RT treatments < 131 Gy appeared to be at higher risk of progression (4-yr b-PFS: 19% vs 33%, p = 0.145). Cumulative re-irradiation constraints that appear to be safe are D 30% < 57.9 Gy for bladder and D 30% < 66.0 Gy, D 60 % < 38.0 Gy and V 122.1 Gy < 5% for rectum. Preliminary re-irradiation constraints for bladder and rectum have been reported. Our preliminary investigation may serve to clear some grey areas of PCa re-irradiation. [ABSTRACT FROM AUTHOR]

• Aim of the study is to compare TD and TH plans in HF PMRT setting for selected pts. • TD plans were re-planned on TH with same prescription dose and constraints. • TD compared to TH reached a good target coverage, with an optimal sparing of OARs. Postmastectomy radiotherapy (PMRT) with TomoHelical™ (TH) or TomoDirect™ (TD) allows a uniform target coverage. In this study, we compare treatment plans using TD and TH in the setting of hypofractionated PMRT and immediate breast reconstruction. The TD-treatment plans of breast cancer patients treated between May 2016 and August 2019 were retrospectively selected. All the TD plans were re-planned on TH with the same prescription dose (40.05 Gy/15 fractions) and according to our dose/volume constraints. Data about the 2 treatment plans were compared with a focus on PTV coverage and all the organs at risk (OARs) constraints. Fifty patients for a total number of 100 treatment plans (50 with TD and 50 re-planned with TH) were analyzed. All the median value in the TD PTV CHEST WALL plans fulfilled the predefined planning objectives, even though TH emerged as best for target coverage with statistically significant difference for V90%. TD provided the lowest V95% for the PTV SVC, but the median value was near to the recommended value of 90% (89.8 % vs 98.6% for TD and TH, respectively). Overall, TD reached the best OARs sparing. The main statistically significant differences with TH were for contralateral breast, ipsilateral and contralateral lung. All the other dose values for TH were higher than TD, but they fulfilled the recommended/acceptable predefined planning objectives. In the setting of PMRT, TD compared to TH reached an acceptable target volume coverage, with an optimal sparing of OARs. [ABSTRACT FROM AUTHOR]

In the last 20 years coronary computed tomography angiography (CCTA) gained a pivotal role in the evaluation of patients with suspected coronary artery disease (CAD) as finally recognized by the ESC guidelines on stable CAD. Technological advances have progressively improved the temporal resolution of CT scanners, contemporary reducing acquisition time, radiation dose and contrast volume needed for the whole heart volume acquisition, further expanding the role of cardiac CT beyond coronary anatomy evaluation. Aim of the present review is to discuss use and benefit of cardiac CT for the planning and preparation of VT ablation. [ABSTRACT FROM AUTHOR]

• Dosimetric uncertainties of a mixed beam approach (CIRT + IMRT) were evaluated. • DIR performances were evaluated through validated similarity parameters. • Apart from femoral heads, all OARs underwent intermediate to large deformation. • A comprehensive "deformation score" for DIR evaluation was proposed. • CIRT allows a better OARs sparing while increasing the efficacy. The aim was to evaluate dosimetric uncertainties of a mixed beam approach for patients with high-risk prostate cancer (PCa). The treatment consists of a carbon ion radiotherapy (CIRT) boost followed by whole-pelvis intensity-modulated RT (IMRT). Patients were treated with a CIRT boost of 16.6 Gy/4 fractions followed by whole-pelvis IMRT of 50 Gy/25 fractions, with consequent long term androgen deprivation therapy. Deformable computed tomography image registration (DIR) was performed and corresponding doses were used for plan sum. A comparative IMRT photon plan was obtained as whole-pelvis IMRT of 50 Gy/25 fractions followed by a boost of 28 Gy/14 fractions. DIR performances were evaluated through structure-related and image characteristics parameters. Until now, five patients out of ten total enrolled ended the treatment. Dosimetric parameters were lower in CIRT + IMRT than IMRT-only plans for all organs at risk (OARs) except femoral heads. Regarding DIR evaluation, femoral heads were the less deformed OAR. Penile bulb, bladder and anal canal showed intermediate deformation. Rectum was the most deformed. DIR algorithms were patient (P)-dependent, as performances were the highest for P3 and P4, intermediate for P2 and P5, and the lowest for P1. CIRT allows better OARs sparing while increasing the efficacy due to the higher radio-biological effect of carbon ions. However, a mixed beam approach could introduce DIR problems in multi-centric treatments with different operative protocols. The development of this prospective trial will lead to more mature data concerning the clinical impact of implementing DIR procedures in dose accumulation applications for high-risk PCa treatments. [ABSTRACT FROM AUTHOR]

• ANACONDA performances can be influenced by bladder filling fluctuation if no controlling ROIs are selected. • ANACONDA performances improve increasing the number of controlling ROIs selected. • ANACONDA reaches a saturation level after a defined ROIs subset is selected. • Global_DSC and global_CC could be useful tools for DIR performances comparison. • DSC present higher sensitivity to DIR differences. Evaluation of Raystation ANAtomically CONstrained Deformation Algorithm (ANACONDA) performance to different urinary bladder filling levels in male pelvis anatomic site varying the controlling Regions Of Interest (ROIs). Different image datasets were obtained with ImSimQA (Oncology System Limited, Shrewsbury, UK) to evaluate ANACONDA performances (RaySearch Laboratories, Stockholm, Sweden). Deformation vector fields were applied to a synthetic man pelvis and a real patient computed tomography (CT) dataset (reference CTs) resulting in deformed CTs (target CTs) with various bladder filling levels. Different deformable image registrations (DIRs) were generated between each target CTs and reference CTs varying the controlling ROIs subset. Deformed ROIs were mapped from target CT to reference CT and then compared to reference ROIs. Evaluation was performed by Dice Similarity Coefficient (DSC), Correlation Coefficient (CC), Mean Distance to Agreement (MDA), maximum Distance to Agreement (maxDA) and with the introduction of global DSC (global_DSC) and global CC (global_CC) parameters. In both synthetic and real patient CT cases, DSC scored less than 0.75 and MDA greater than 3 mm when no ROIs or only bladder were exploited as controlling ROI. DSC and CC increased by increasing the number of controlling ROIs selected whereas, an opposite behavior was observed for MDA and maxDA. ANACONDA performances can be influenced by bladder filling fluctuation if no controlling ROIs are selected. Global_DSC and global_CC are useful parameters to quantitatively compare DIR algorithms. DIR performances improve by increasing the number of controlling ROIs selected, reaching a saturation level after a defined ROIs subset selection. [ABSTRACT FROM AUTHOR]

• Normalizing images with respect to healthy prostate tissue is optimal. • Histogram-based normalization should be used otherwise. • Over 87% of radiomic features drastically change after normalization. • Improper normalization is worse than no normalization. The variance in intensities of MRI scans is a fundamental impediment for quantitative MRI analysis. Intensity values are not only highly dependent on acquisition parameters, but also on the subject and body region being scanned. This warrants the need for image normalization techniques to ensure that intensity values are consistent within tissues across different subjects and visits. Many intensity normalization methods have been developed and proven successful for the analysis of brain pathologies, but evaluation of these methods for images of the prostate region is lagging. In this paper, we compare four different normalization methods on 49 T2-w scans of prostate cancer patients: 1) the well-established histogram normalization, 2) the generalized scale normalization, 3) an extension of generalized scale normalization called generalized ball-scale normalization, and 4) a custom normalization based on healthy prostate tissue intensities. The methods are compared qualitatively and quantitatively in terms of behaviors of intensity distributions as well as impact on radiomic features. Our findings suggest that normalization based on prior knowledge of the healthy prostate tissue intensities may be the most effective way of acquiring the desired properties of normalized images. In addition, the histogram normalization method outperform the generalized scale and generalized ball-scale methods which have proven superior for other body regions. [ABSTRACT FROM AUTHOR]

Highlights • MVCT dose of pre-treatment images depends on scanning pitch. • Scanning pitch and reconstruction interval do not affect noise, contrast or qualitative spatial resolution of MVCT images. • Appropriate choice of imaging parameters should concern cranio-caudal resolution for IGRT and ART purposes. Abstract Background The aim of this study is to evaluate the dose delivered and the image quality of pre-treatment MVCT images with Hi-Art TomoTherapy system, varying acquisition and reconstruction parameters. Materials and methods Catphan 500 MVCT images were acquired with all acquisition pitch and reconstruction intervals; image quality was evaluated in terms of noise, uniformity, contrast linearity, contrast-to-noise ratio (CNR) and spatial resolution with the Modulation Transfer Function (MTF). Dose was evaluated as Multi Slice Average Dose (MSAD w) and measurements were performed with the Standard TomoTherapy® Quality Assurance Kit composed by the TomoTherapy Phantom, the Exradin A1SL ion chamber and TomoElectrometer. For each pitch-reconstruction interval, acquisitions were repeated 5 times. Results Differences in noise and uniformity, though statistically significant in some cases, were very small: noise ranged from 2.3% for Coarse – 3 mm to 2.4% for Coarse – 6 mm, while uniformity passed from 99.5% for Coarse – 6 mm to 99.8% for Normal – 4 mm. No differences at all were found for CNR for high and low density inserts, while MTF was higher for pitch Coarse , even if no differences in spatial resolution were observed visually (spatial resolution was up to 4 lp/cm for all combinations of pitch and reconstruction interval). Dose was dependent on pitch, being 1.0 cGy for Coarse , 1.5 cGy for Norma l and 2.85 cGy for Fine. Conclusions We observed negligible differences in image quality among different pitch and reconstruction interval, thus, considerations regarding pre-treatment imaging modalities should be based only on dose delivered and on the desired resolution along the cranio-caudal axis for image-guided radiotherapy and adaptive radiotherapy purposes. [ABSTRACT FROM AUTHOR]

Abstract The aim of this work was to isolate and investigate different yeast strains obtained in the Brazilian Midwest Region. The alcohol fermenting industrial yeast Saccharomyces cerevisiae CAT-1 and another 3 strains previously isolated from a sugar and alcohol mill were also investigated. In this sense, 45 strains were isolated from fruits and chicken litter. They were evaluated through biochemical and molecular analyzes. Then, it was proceded the enzymatic evaluation and the molecular identification of 13 potential strains, selected due to the fermentation capacity of the substrates glucose, fructose and sucrose. One isolate was distinguished by its short time of fermentation (Candida glabrata Recol 43) and another 3 by their high activity of pyruvate dehydrogenase (Candida glabrata Recol 41, Candida parapsilosis Recol 29 and Meyerozyma guilliermondii Recol 9). The complete characterization performed here helped to identify novel yeasts with potential for biotechnological applications in biofuel and food industries. Graphical abstract fx1 Highlights • Yeast strains were isolated from Brazilian fruits, chicken litter, and an alcohol mill. • 49 yeast strains were characterized through biochemical and molecular analyzes. • 13 newly isolates were identified due to the fermentation capacity on different sugars. • Potential applications were identified based on characterization. [ABSTRACT FROM AUTHOR]

Purpose To evaluate inter-fraction tumor localization errors (TE) in the RapidArc® treatment of pelvic cancers based on CBCT. Appropriate CTV-to PTV margins in a non-IGRT scenario have been proposed. Methods Data of 928 patients with prostate, gynecological, and rectum/anal canal cancers were retrospectively analyzed to determine systematic and random localization errors. Two protocols were used: daily online IGRT (d-IGRT) and weekly IGRT. The latter consisted in acquiring a CBCT for the first 3 fractions and subsequently once a week. TE for patients who underwent d-IGRT protocol were calculated using either all CBCTs or the first 3. Results The systematic (and random) TE in the AP, LL, and SI direction were: for prostate bed 2.7(3.2), 2.3(2.8) and 1.9(2.2) mm; for prostate 4.2(3.1), 2.9(2.8) and 2.3(2.2) mm; for gynecological 3.0(3.6), 2.4(2.7) and 2.3(2.5) mm; for rectum 2.8(2.8), 2.4(2.8) and 2.3(2.5) mm; for anal canal 3.1(3.3), 2.1(2.5) and 2.2(2.7) mm. CTV-to-PTV margins determined from all CBCTs were 14 mm in the AP, 10 mm in the LL and 9–9.5 mm in the SI directions for the prostate and the gynecological groups and 9.5–10.5 mm in AP, 9 mm in LL and 8–10 mm in the SI direction for the prostate bed and the rectum/anal canal groups. If assessed on the basis of the first 3 CBCTs, the calculated CTV-to-PTV margins were slightly larger. Conclusions without IGRT, large CTV-to-PTV margins up to 15 mm are required to account for inter-fraction tumor localization errors. Daily IGRT should be used for all hypo-fractionated treatments to reduce margins and avoid increased toxicity to critical organs. [ABSTRACT FROM AUTHOR]

• Efficient unsupervised learning method for UHI analysis at the city scale. • Urban feature extraction with GMM clustering: 10 microclimatic clusters. • Simulated UHII with UWG tool and validation with urban on-site measurements. • Yearly average UHII analysis of Canton of Geneva ranging from 1.7 °C to 2.2 °C. • Methodology supports urban planning is reproducible and computationally efficient. This study presents a fully reproducible clustering-based methodology for the assessment of the urban heat island intensity (UHII) at the territory scale, using parametric microclimate models and limited computational resources. In large-scale climate modeling, a common preliminary operation is to utilize the well-established Local Climate Zone classification to characterize the thermal response of urban areas based on morphology. With the increasing availability of urban datasets, data-driven approaches can be implemented to quantitatively derive meaningful urban features without relying on a standardized classification. The proposed methodology employs a Gaussian Mixture Model clustering algorithm to partition the urban territory into a suitable number of homogeneous microclimate zones, enabling the calculation and mapping of the UHII for each zone through the Urban Weather Generator (UWG) tool. The developed approach is applied to the Canton of Geneva, Switzerland, identifying ten microclimatic areas and analyzing the spatiotemporal variation of UHII. Results show yearly average values of UHII ranging from 1.7 °C to 2.2 °C, depending on urban morphology. The simulated values are partially validated by comparison with on-site measurements from two urban weather stations, yielding a satisfactory agreement. The methodology can support urban planning with the goal of avoid overheating through a large-scale mapping. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose Post-implant CT-scanning is an essential part of permanent prostate brachytherapy. However, the evaluation of post-implant CT dosimetry is not straightforward due to the edema that can modify the dose to the prostate and to the organs at risk. The aim of this study is to evaluate the impact of the timing of the post-implant CT-scan on the dosimetric results and to verify if the Day 0 scan findings can predict Day 50 scanning. Methods 136 consecutive patients who received monotherapy with I-125 implants were selected for this study. Two sets of 8 dosimetric quality parameters corresponding to 2 different CT-scans (Day 0 and Day 50) were calculated and compared. The dosimetric parameters included are the percentage volume of the post-implant prostate receiving 80%, 100% and 150% of the prescribed dose, the doses covering 80% and 90% of the prostate volume and the Dose Homogeneity Index. The values of the dose covering 1 cm 3 of the rectum and urethra were assessed. Results All the dosimetric parameters of the Day 50 were higher than those of the Day 0 scan. Linear functions were obtained that calculate D 90 and V 100 values at Day 50 based on the Day 0 findings. Rectal and urethral parameters tended to be underestimated on Day 0 CT-scan relative to Day 50 based dosimetry. Conclusions Predicting the Day 50 dosimetry from the Day 0 scan could be a possible alternative to a Day 50 scan only in specific situations, but with a degree of uncertainty in the predicted values. [ABSTRACT FROM AUTHOR]

Background and purpose 3D printing is rapidly evolving and further assessment of materials and technique is required for clinical applications. We evaluated 3D printed boluses with acrylonitrile butadiene styrene (ABS) and polylactide (PLA) at different infill percentage. Material and methods A low-cost 3D printer was used. The influence of the air inclusion within the 3D printed boluses was assessed thoroughly both with treatment planning system (TPS) and with physical measurements. For each bolus, two treatment plans were calculated with Monte Carlo algorithm, considering the computed tomography (CT) scan of the 3D printed bolus or modelling the 3D printed bolus as a virtual bolus structure with a homogeneous density. Depth dose measurements were performed with Gafchromic films. Results High infill percentage corresponds to high density and high homogeneity within bolus material. The approximation of the bolus in the TPS as a homogeneous material is satisfying for infill percentages greater than 20%. Measurements performed with PLA boluses are more comparable to the TPS calculated profiles. For boluses printed at 40% and 60% infill, the discrepancies between calculated and measured dose distribution are within 5%. Conclusions 3D printing technology allows modulating the shift of the build-up region by tuning the infill percentage of the 3D printed bolus in order to improve superficial target coverage. [ABSTRACT FROM AUTHOR]

Most patients with ductal carcinoma in situ of the breast (DCIS) are eligible for breast conservation treatment. The key management decision is whether to add radiotherapy and/or endocrine therapy to minimize the risk of a subsequent recurrence. Recent analyses indicating a lack of benefit in terms of breast cancer-associated mortality have suggested that more conservative approaches, omitting adjuvant therapy or even surgery, may be advisable in selected patients. These mortality observations are directly influenced by widespread use of mammographic screening which has opened a Pandora's box of subclinical DCIS and early invasive lesions. Confusion as to how aggressively such possibly indolent lesions should be treated has led to misunderstandings among patients and medical professionals. While awaiting further prospective evidence from clinical trials, we endorse an active treatment of DCIS as the standard of care. Our rationale is twofold: invasive recurrences are associated with an increase in breast cancer mortality, which is not the only relevant endpoint for DCIS. The benefit of complete surgical excision, adjuvant radiotherapy and endocrine treatment in preventing recurrence and invasive progression has been demonstrated in DCIS. The challenge now is how to identify DCIS patients who will not progress to invasive carcinoma even without complete excision and, at the other extreme, those patients at the highest risk who require mastectomy for local control. The current controversies over whether and which adjuvant therapy should be implemented can at least in part be addressed by developing effective doctor-patient communications that enable mutual understanding about the management of this biologically heterogeneous disease. [ABSTRACT FROM AUTHOR]

Objectives Atlas-based automatic segmentation (ABAS) addresses the challenges of accuracy and reliability in manual segmentation. We aim to evaluate the contribution of specific-purpose in ABAS of breast cancer (BC) patients with respect to generic-purpose libraries. Materials and methods One generic-purpose and 9 specific-purpose libraries, stratified according to type of surgery and size of thorax circumference, were obtained from the computed tomography of 200 BC patients. Keywords about contralateral breast volume and presence of breast expander/prostheses were recorded. ABAS was validated on 47 independent patients, considering manual segmentation from scratch as reference. Five ABAS datasets were obtained, testing single-ABAS and multi-ABAS with simultaneous truth and performance level estimation (STAPLE). Center of mass distance (CMD), average Hausdorff distance (AHD) and Dice similarity coefficient (DSC) between corresponding ABAS and manual structures were evaluated and statistically significant differences between different surgeries, structures and ABAS strategies were investigated. Results Statistically significant differences between patients who underwent different surgery were found, with superior results for conservative-surgery group, and between different structures were observed: ABAS of heart, lungs, kidneys and liver was satisfactory (median values: CMD<2 mm, DSC≥0.80, AHD<1.5 mm), whereas chest wall, breast and spinal cord obtained moderate performance (median values: 2 mm ≤ CMD<5 mm, 0.60 ≤ DSC<0.80, 1.5 mm ≤ AHD<4 mm) and esophagus, stomach, brachial plexus and supraclavicular nodes obtained poor performance (median CMD≥5 mm, DSC<0.60, AHD≥4 mm). The application of STAPLE algorithm generally yields higher performance and the use of keywords improves results for breast ABAS. Conclusion The homogeneity in the selection of atlases based on multiple anatomical and clinical features and the use of specific-purpose libraries can improve ABAS performance with respect to generic-purpose libraries. [ABSTRACT FROM AUTHOR]

Purpose Dosimetric assessment of high dose rate (HDR) brachytherapy applicators, printed in 3D with acrylonitrile butadiene styrene (ABS) at different infill percentage. Materials and methods A low-cost, desktop, 3D printer (Hamlet 3DX100, Hamlet, Dublin, IE) was used for manufacturing simple HDR applicators, reproducing typical geometries in brachytherapy: cylindrical (common in vaginal treatment) and flat configurations (generally used to treat superficial lesions). Printer accuracy was investigated through physical measurements. The dosimetric consequences of varying the applicator’s density by tuning the printing infill percentage were analysed experimentally by measuring depth dose profiles and superficial dose distribution with Gafchromic EBT3 films (International Specialty Products, Wayne, NJ). Dose distributions were compared to those obtained with a commercial superficial applicator. Results Measured printing accuracy was within 0.5 mm. Dose attenuation was not sensitive to the density of the material. Surface dose distribution comparison of the 3D printed flat applicators with respect to the commercial superficial applicator showed an overall passing rate greater than 94% for gamma analysis with 3% dose difference criteria, 3 mm distance-to-agreement criteria and 10% dose threshold. Conclusion Low-cost 3D printers are a promising solution for the customization of the HDR brachytherapy applicators. However, further assessment of 3D printing techniques and regulatory materials approval are required for clinical application. [ABSTRACT FROM AUTHOR]

The aim of this review is to present the available radiobiological, technical and clinical data about extreme hypofractionation in primary prostate cancer radiotherapy. The interest in this technique is based on the favourable radiobiological characteristics of prostate cancer and supported by advantageous logistic aspects deriving from short overall treatment time. The clinical validity of short-term treatment schedule is proven by a body of non-randomised studies, using both isocentric (LINAC-based) or non-isocentric (CyberKnife®-based) stereotactic body irradiation techniques. Twenty clinical studies, each enrolling more than 40 patients for a total of 1874 treated patients, were revised in terms of technological setting, toxicity, outcome and quality of life assessment. The implemented strategies for the tracking of the prostate and the sparing of the rectal wall have been investigated with particular attention. The urinary toxicity after prostate stereotactic body irradiation seems slightly more pronounced as compared to rectal adverse events, and this is more evident for late occurring events, but no worse as respect to conventional fractionation schemes. As far as the rate of severe acute toxicity is concerned, in all the available studies the treatment was globally well tolerated. While awaiting long-term data on efficacy and toxicity, the analysed studies suggest that the outcome profile of this approach, alongside the patient convenience and reduced costs, is promising. Forty-eight ongoing clinical trials are also presented as a preview of the expectation from the near future. [ABSTRACT FROM AUTHOR]

Radiotherapy improves local control in breast cancer (BC) patients which increases overall survival in the long term. Improvements in treatment planning and delivery and a greater understanding of BC behaviour have laid the groundwork for high-precision radiotherapy, which is bound to further improve the therapeutic index. Precise identification of target volumes, better coverage and dose homogeneity have had a positive impact on toxicity and local control. The conformity of treatment dose due to three-dimensional radiotherapy and new techniques such as intensity modulated radiotherapy makes it possible to spare surrounding normal tissue. The widespread use of dose-volume constraints and histograms have increased awareness of toxicity. Real time image guidance has improved geometric precision and accuracy, together with the implementation of quality assurance programs. Advances in the precision of radiotherapy is also based on the choice of the appropriate fractionation and approach. Adaptive radiotherapy is not only a technical concept, but is also a biological concept based on the knowledge that different types of BC have distinctive patterns of locoregional spread. A greater understanding of cancer biology helps in choosing the treatment best suited to a particular situation. Biomarkers predictive of response play a crucial role. The combination of radiotherapy with molecular targeted therapies may enhance radiosensitivity, thus increasing the cytotoxic effects and improving treatment response. The appropriateness of an alternative fractionation, partial breast irradiation, dose escalating/de-escalating approaches, the extent of nodal irradiation have been examined for all the BC subtypes. The broadened concept of adaptive radiotherapy is vital to high-precision treatments. [ABSTRACT FROM AUTHOR]

Purpose Accurate localization is crucial in delivering safe and effective stereotactic body radiation therapy (SBRT). The aim of this study was to analyse the accuracy of image-guidance using the cone-beam computed tomography (CBCT) of the VERO system in 57 patients treated for lung SBRT and to calculate the treatment margins. Materials and methods The internal target volume (ITV) was obtained by contouring the tumor on maximum and mean intensity projection CT images reconstructed from a respiration correlated 4D-CT. Translational and rotational tumor localization errors were identified by comparing the manual registration of the ITV to the motion-blurred tumor on the CBCT and they were corrected by means of the robotic couch and the ring rotation. A verification CBCT was acquired after correction in order to evaluate residual errors. Results The mean 3D vector at initial set-up was 6.6 ± 2.3 mm, which was significantly reduced to 1.6 ± 0.8 mm after 6D automatic correction. 94% of the rotational errors were within 3°. The PTV margins used to compensate for residual tumor localization errors were 3.1, 3.5 and 3.3 mm in the LR, SI and AP directions, respectively. Conclusions On-line image guidance with the ITV–CBCT matching technique and automatic 6D correction of the VERO system allowed a very accurate tumor localization in lung SBRT. [ABSTRACT FROM AUTHOR]

Background: Hypofractionated proton beam radiotherapy (PBT) is gaining attention in early-stage non-small cell lung cancer (ES-NSCLC). However, there is a large unmet need to define indications, prescription doses and potential adverse events of protons in this clinical scenario. Hence, the present work aims to provide a critical literature revision, and to investigate associations between fractionation schedules/ biological effective doses (BEDs), oncological outcomes and toxicities.Materials and Methods: This systematic review and meta-analysis complied with the PRISMA recommendations. Inclusion criteria were: 1) curative-intent hypofractionated PBT for ES-NSCLC (≥3 Gy(RBE)/fraction), 2) report of the clinical outcomes of interest, 3) availability of full-text written in English. The bibliographic search was performed on the NCBI Pubmed, Embase and Scopus in September 2021; no other limitations were applied. The BED was calculated for each included study (α/β = 10 Gy); the median BED for all studies was used as a threshold for stratifying selected evidence into "high" and "low"-dose subgroups. Heterogeneity was tested using chi-square statistics; inconsistency was measured with the I2 index. Pooled estimate was obtained by fitting both the fixed-effect and the DerSimonian and Laird random-effect model.Results: Eight studies and 401 patients were available for the meta-analysis; median follow-up was 32.8 months. The median delivered BED was 105.6 Gy(RBE). A BED ≥ 105.6 Gy(RBE) consistently provided superior OS, CSS, DFS and LC rates (i.e.: 4-year OS: 0.56 [0.34-0.76] for BED < 105.6 Gy(RBE) and 0.78 [0.64-0.88] for BED ≥ 105.6 Gy(RBE)). The meta-analysis of proportions showed a comparable probability of developing acute grade ≥ 2 toxicity between the two groups, while the probability of any late grade ≥ 2 event was almost three-times greater for BED ≥ 105.6 Gy(RBE), with rib fractures being more common in the high dose group.Conclusion: Hypofractionated PBT is a safe and effective treatment option for ES-NSCLC; the delivery of BED ≥ 105.6 Gy(RBE) with advanced techniques for uncertainty management has been associated with improved oncological outcomes across all considered time points. [ABSTRACT FROM AUTHOR]

Objectives To compare the patient set-up error detection capabilities of three-dimensional cone beam computed tomography (3D-CBCT) and two-dimensional orthogonal kilovoltage (2D-kV) techniques. Methods 3D-CBCT and 2D-kV projections were acquired on 29 head-and-neck (H&N) patients undergoing Intensity Modulated Radiotherapy (IMRT) on the first day of treatment (time 0) and after the delivery of 40 Gy and 50 Gy. Set-up correction vectors were analyzed after fully automatic image registration as well as after revision by radiation oncologists. The dosimetric effects of the different sensitivities of the two image guidance techniques were assessed. Results A statistically significant correlation among detected set-up deviations by the two techniques was found along anatomical axes (0.60 <  ρ  < 0.72, p < 0.0001); no correlation was found for table rotation (p = 0.41). No evidence of statistically significant differences between the indications provided along the course of the treatment was found; this was also the case when full automatic versus manually refined correction vectors were compared. The dosimetric effects analysis revealed slight statistically significant differences in the median values of the maximum relative dose to mandible, spinal cord and its 5 mm Planning Organ at Risk Volume (0.95%, 0.6% and 2.45%, respectively), with higher values (p < 0.01) observed when 2D-kV corrections were applied. Conclusion A similar sensitivity to linear set-up errors was observed for 2D-kV and 3D-CBCT image guidance techniques in our H&N patient cohort. Higher rotational deviations around the table vertical axis were detected by the 3D-CBCT with respect to the 2D-kV method, leading to a consistent better sparing of organs at risk. [ABSTRACT FROM AUTHOR]

Background We describe a kindred with high-density lipoprotein (HDL) deficiency due to APOA1 g ene mutation in which comorbidities affected the phenotypic expression of the disorder. Methods An overweight boy with hypertriglyceridemia (HTG) and HDL deficiency (HDL cholesterol 0.39 mmol/L, apoA-I 40 mg/dL) was investigated. We sequenced the candidate genes for HTG ( LPL, APOC2 , APOA5, GPIHBP1, LMF1 ) and HDL deficiency ( LCAT, ABCA1 and APOA1 ), analyzed HDL subpopulations, measured cholesterol efflux capacity (CEC) of sera and constructed a model of the mutant apoA-I. Results No mutations in HTG-related genes, ABCA1 and LCAT were found. APOA1 sequence showed that the proband, his mother and maternal grandfather were heterozygous of a novel frameshift mutation (c.546_547delGC), which generated a truncated protein (p.[L159Afs*20]) containing 177 amino acids with an abnormal C-terminal tail of 19 amino acids. Trace amounts of this protein were detectable in plasma. Mutation carriers had reduced levels of LpA-I, preβ-HDL and large HDL and no detectable HDL-2 in their plasma; their sera had a reduced CEC specifically the ABCA1-mediated CEC. Metabolic syndrome in the proband explains the extremely low HDL cholesterol level (0.31 mmol/L), which was half of that found in the other carriers. The proband's mother and grandfather, both presenting low plasma low-density lipoprotein cholesterol, were carriers of the β-thalassemic trait, a condition known to be associated with a reduced low-density lipoprotein cholesterol and a reduced prevalence of cardiovascular disease. This trait might have delayed the development of atherosclerosis related to HDL deficiency. Conclusions In these heterozygotes for apoA-I truncation, the metabolic syndrome has deleterious effect on HDL system, whereas β-thalassemia trait may delay the onset of cardiovascular disease. [ABSTRACT FROM AUTHOR]

Purpose To suggest a comprehensive testing scheme to evaluate the geometric and dosimetric accuracy and the imaging dose of the VERO dynamic tumour tracking (DTT) for its clinical implementation. Methods Geometric accuracy was evaluated for gantry 0° and 90° in terms of prediction (E P ), mechanical (E M ) and tracking (E T ) errors for sinusoidal patterns with 10 and 20 mm amplitudes, 2–6 s periods and phase shift up to 1 s and for 3 patient patterns. The automatic 4D model update was investigated simulating changes in the breathing pattern during treatment. Dosimetric accuracy was evaluated with gafchromic films irradiated in static and moving phantom with and without DTT. The entrance skin dose (ESD) was assessed using a solid state detector and gafchromic films. Results The RMS of E P , E M , and E T were up to 0.8, 0.5 and 0.9 mm for all non phased-shifted motion patterns while for the phased-shifted ones, E P and E T increased to 2.2 and 2.6 mm. Up to 4 updates are necessary to restore a good correlation model, according to type of change. For 100 kVp and 1 mA s X-ray beam, the ESD per portal due to 20 s fluoroscopy was 16.6 mGy, while treatment verification at a frequency of 1 Hz contributed with 4.2 mGy/min. Conclusions The proposed testing scheme highlighted that the VERO DTT system tracks a moving target with high accuracy. The automatic update of the 4D model is a powerful tool to guarantee the accuracy of tracking without increasing the imaging dose. [ABSTRACT FROM AUTHOR]

The work optimized the production of xylanases by solid-state cultivation by Trichoderma koningii and Trichoderma pseudokoningii. The xylanases were biochemically characterized, the catalytic potential of enzymatic extracts and their use as an additive in the feeding of ruminants were evaluated. The higher production of xylanases by T. koningii , approximately 524.3 U g−1 (or 52.43 UmL−1), was obtained for cultivation in a substrate composed of wheat bran and sugarcane bagasse in a 4:1 g ratio, respectively, containing 60% initial moisture, and kept at 20 °C for 120 h. The xylanase used by T. koningii showed excellent activity at pH 4.5 and 50 °C and remained stable at pH 3.0–9.5 and for 1 h at 45 °C. T. pseudokoningii had a higher production of xylanase, 721.0 U g−1 (72.10 UmL−1), when grown in wheat bran, with 50% initial moisture, at 25 °C for 96 h. The xylanases produced by T. pseudokoningii showed greater catalytic activity at pH 4.5 and 55 °C and were stable at pH 3.0–9.5 and for 1 h at 50 °C. The best results of in vitro digestibility were obtained in Mombaça grass containing the enzymatic extract of T. koningii , reaching a maximum gain of 12% in digestibility, expressed in dry mass. The chromatographic profile of the products resulting from the enzymatic hydrolysis of xylan indicated the predominant action of endoxylanases. Additionally, the enzymatic extracts showed reduced cellulolytic activity, which enables its use in cellulose pulp bio-bleaching processes. • Xylanase production by Trichoderma koningii and Trichoderma pseudokoningii. • Enzymes produced in low-cost media: wheat bran and sugar cane bagasse. • Enzymatic extracts with reduced cellulolytic activity. • Potential for application of enzymes as digestive additives in cattle diet. [ABSTRACT FROM AUTHOR]

BACKGROUND: In the last twenty years Home Enteral Nutrition (HEN) has undergone considerable development and has determined economic and organisational changes. The aim of this study is to evaluate the epidemiological data of 655 patients treated in the five-year period (2001-2005) in an area in the North-East of Italy. METHODS: The following data were analysed at the initiation of HEN: age, sex, pathology, Karnofsky index, type of enteral access device, presence of pressure ulcers, weight, body mass index, haematochemical tests, daily enteral intake. Length of therapy and patient survival were then considered. The outcome was based on patient mortality and the patient's ability to resume oral nutrition. RESULTS: HEN was prescribed for the following pathologies: 26.7% neurovascular, 40.9% neurodegenerative, 11.5% head-neck cancer, 9.8% abdominal cancer, 1.5% head injury, 2.6% congenital anomaly, 7.0% other pathologies. Before commencement of enteral feeding an average of 22.9% weight loss from past weight was observed across all indications for HEN. Mean incidence (cases/10(6) inhabitants/year) and prevalence (cases/10(6) inhabitants) were respectively 308.7 (range 80.7-355.6) and 379.8 (range 138.7-534.6). The median length of HEN was 196 days; only 7.9% of patients resumed oral nutrition. The median survival rate was 9.1 months and resulted influenced by age (Odds ratio: 1.80; 95% Confidence Interval: 1.19-2.72), sex (0.22; 0.08-0.59), and Karnofsky index (0.65; 0.43-0.97). Resumption of oral nutrition was influenced by age (0.50; 0.36-0.68), sex (2.50; 1.23-5.06), Karnofsky index (1.55; 1.15-2.10) and type of enteral access device (0.44; 0.26-0.76). CONCLUSIONS: Efficient organisation means being able to look after a greater number of patients undergoing HEN, raising awareness regarding the nutritional treatment. [ABSTRACT FROM AUTHOR]

• Epistemological and social dimension of knowledge co-production. • Challenges of coproducing climate services for agricultural production. • Power structure's role in the knowledge co-production process and climate impacts. • Heterogeneous knowledge dialogue for socially meaningful climate products. • Knowledge co-production for individual and collective climate change adaptation. When engaging in an interdisciplinary and intersectoral knowledge coproduction process, what premises should (academic and non-academic) participants consider to prevent power dynamics and divergent interests from becoming epistemological obstacles (Bachelard, 1974)? What methodological devices should be adopted to enable a productive dialogue between heterogeneous actors and knowledge? Despite the plethora of literature on the relevance of participatory approaches and the promotion of open science to produce socially meaningful knowledge, most works neglect central challenges present in any coproduction experience. Namely, how to deal with power dynamics, how to challenge the identity anchors of the participants and how to ensure the epistemological conditions for initiating long-term collaboration. Hence, based on these concerns, this paper puts forth the theoretical-methodological basis of a knowledge coproduction approach for the development of climate services for family farming. In addition, we present two major results achieved in the framework of a coproduction process involving academic and non-academic participants: the development of a community-based rainfall monitoring network in the eastern region of the South American Gran Chaco and the codesign of a smartphone application. [ABSTRACT FROM AUTHOR]

Background and Purpose: Between 30% and 47% of patients treated with definitive radiotherapy (RT) for prostate cancer are at risk of intraprostatic recurrence during follow-up. Re-irradiation with stereotactic body RT (SBRT) is emerging as a feasible and safe therapeutic option. However, no consensus or guidelines exist on this topic. The purpose of this ESTRO ACROP project is to investigate expert opinion on salvage SBRT for intraprostatic relapse after RT.Materials and Methods: A 40-item questionnaire on salvage SBRT was prepared by an internal committee and reviewed by a panel of leading radiation oncologists plus a urologist expert in prostate cancer. Following the procedure of a Delphi consensus, 3 rounds of questionnaires were sent to selected experts on prostate re-irradiation.Results: Among the 33 contacted experts, 18 (54.5%) agreed to participate. At the end of the final round, participants were able to find consensus on 14 out of 40 questions (35% overall) and major agreement on 13 questions (32.5% overall). Specifically, the consensus was reached regarding some selection criteria (no age limit, ECOG 0-1, satisfactory urinary flow), diagnostic procedures (exclusion of metastatic disease, SBRT target defined on the MRI) and therapeutic approach (no need for concomitant ADT, consideration of the first RT dose, validity of Phoenix criteria for salvage SBRT failure).Conclusion: While awaiting the results of ongoing studies, our ESTRO ACROP Delphi consensus may serve as a practical guidance for salvage SBRT. Future research should address the existing disagreements on this promising approach. [ABSTRACT FROM AUTHOR]

Purpose PRRT with 90Y-DOTATOC and 177Lu-DOTATATE showed up to 35% objective responses in NETs and acceptable toxicity. Given NET indolent behavior, multiple treatments are sequentially applied; EBRT is proposed frequently as oligometastatic/palliative setting. Our aim was to assess whether the combination of PRRT and EBRT (PRRT + EBRT) arise concerns about tolerability. Methods Over our 807 patients receiving PRRT (1997–2014), 17% underwent also EBRT (14% after PRRT, 3% before PRRT). Among these, 25 patients had dosimetry and clinical data of PRRT + EBRT. The primary NETs were pancreas (12), lung (7), others (6), with multiple metastases in liver (13), bone (10), others (11). EBRT was adjuvant in 18 sites, palliative in 22. Bone metastases were treated with 3D conformal EBRT. Oligometastaseswere treated with image-guided IMRT or stereotactic EBRT, accounting for absorbed doses (AD) from PRRT. AD to Organs At Risk (OARs) and tumours were assessed and toxicity investigated (CTCAE v4). For PRRT, OARs were kidneys and red-marrow; AD to the liver was also evaluated. OARs for EBRT depended on the tumour site. Results The table reports the median value (range) of administered activities and absorbed doses to OARs for the PRRT as well as doses delivered with EBRT. Individual metabolism leaded to large AD variability in PRRT (tumour: 1–42 Gy/GBq, 90Y-DOTATOC; 1–56 Gy/GBq, 177Lu-DOTATATE).No severe red-marrow toxicity was observed (14 patients grade I-II; 3 none); no kidney toxicity was shown but in 1 patient (grade I). Median (range) follow-up was 3.5 (0.2–12.3) years. 7 patients died. Conclusions PRRT and EBRT have different OARs, with the great potential to increase AD to tumours without increasing toxicity, especially in red-marrow and liver. This opens the way to future prospective studies. However, EBRT irradiating liver metastases may (rarely) deliver non-negligible AD to kidneys once summed to AD from PRRT. PRRT + EBRT imposes multidisciplinary dosimetry discussion. [ABSTRACT FROM AUTHOR]

Abstract Purpose To investigate the impact of 68 Ga-DOTATOC PET/CT in addition to MRI and CT for retrospectively assessing the GTV delineation of meningiomas of the skull base in patients treated with particle therapy. Methods Sixteen patients underwent 68 Ga-DOTATOC PET/CT for diagnosis followed by constract-enhanced (CE) MRI and CT for treatment planning with particle therapy.GTV was defined on the CE-MRI fused to the simulation CT (CT sim) integrating information from the PET/CT. Three methods to delineate the PET volume were evaluated:manual ( PET man ), semiautomatic (42% threshold of SUV max , PET SUV 42 % ) and automatic adaptive thresholding method incorporating PET reconstruction parameters ( PET auto ) (iTA, TA). PET man volumes were delineated by the same nuclear medicine physician, while PET SUV 42 % and PET auto volumes were determined by medical physicists.The PET/CT, CE-RMI and CT sim were co-registered with a deformable image registration algorithm using the MIM Software.The overlapping region of MRI and PET man resulted in GTV common . Results The lesions had a median SUV max of 12.1 ± 6.8 (range:3.2–32.6).Overall, the GTV-MRI was larger than GTV-PET man in 7 patients (43.8%), smaller in 6 (37.5%) and almost the same in 3 (18.8%).The median value of the different volumes were:GTV-MRI = 14.3 ± 37.2 cc, GTV-PET man = 14.4 ± 47.0 cc , GTV common = 12.2 ± 33.6 cc , GTV-PET SUV 42 % = 8.3 ± 18.3 cc , GTV- PET auto = 11.3 ± 26.2 cc. GTV-PET SUV 42 % were always smaller than GTV-PET man (Δ = - 51.0 ± 32.7 %) and GTV-PET auto (Δ = - 21.5 ± 12.7 %) being variations in tumor heterogeneity not accounted for. Largest differences were observed for lesions showing high SD of SUV. The median difference between GTV-PET man and GTV-PET auto was 39.6 ± 29.5%. Conclusions 68 Ga-DOTATOC-PET/CT seems to improve the target volume delineation in skull base meningiomas, often leading to a reduction of GTV compared with MRI. The automatic adaptive thresholding delineation method may provide robust and reliable tool to help physician in segmenting PET images, reducing inter- and intra-observer variability. [ABSTRACT FROM AUTHOR]

Abstract Purpose To assess dose and image quality in phantom with HiArt TomoTherapy and to evaluate the feasibility to acquire pre-treatment images with a pitch Coarse with a 3 mm slice thickness (ST) instead of the currently used 6 mm ST. Methods Multiple Scan Average Dose ( MSAD w) was calculated according to the literature using a Exradin ion-chamber in a TomoPhant placed at the isocenter. Measurements were repeated 5 times for each combination pitch -ST reconstruction (Fine 1 and 2 mm, Normal 2 and 4 mm and Coarse 3 and 6 mm) for 2 different scan lengths (5 and 10 cm). Image quality was assessed scanning a Catphan500 for 5 times with each combination of pitch and ST and the collected data were evaluated in terms of contrast linearity, signal uniformity, noise, Signal-to-noise (SNR) ratio. In addition, spatial resolution was evaluated both qualitatively and quantitatively. Results MSAD w for the 10-cm scan length was of 1.03 ± 0.01 cGy for pitch Coarse, 1.48 ± 0.01 cGy for pitch Normal and 2.83 ± 0.01 cGy for pitch Fine. We found slight lower values for the 5-cm scan length (0.94 ± 0.01 cGy, 1.36 ± 0.01 cGy and 2.67 ± 0.01 cGy for pitch Coarse, Normal and Fine, respectively) due to the lower scattered radiation. Considering image quality, signal uniformity was comparable among the different pitch-ST combinations; noise ranged from 2.4% to 2.5% with no significant differences changing pitch or ST. Signal-to-noise ratio ranged from 40.0 ± 2.0 from pitch Coarse-6 mm to 42.1 ± 1.2 for Normal-4 mm but we found no statistical significance in these differences. MTF 50 % was of 3.3 lp/cm for Coarse, 2.7 lp/cm for Normal and 2.5 lp/cm for Fine. Anyway these differences were not empirically detectable on the images, in which we observed up to 4 lp/cm for all the pitch-ST combinations. Conclusions The acquisitions of pre-treatment images with pitch Coarse and 3 mm ST reconstruction is feasible and justified according to our results. [ABSTRACT FROM AUTHOR]

Purpose Formulation of a global Unified Dosimetry Index (gUDI) for the evaluation of ultra-hypofractionated prostate Volumetric Modulated Arc Therapy (VMAT by RapidArc) treatment plans. Methods Radiotherapy treatment plan quality can be assessed in terms of dose coverage, conformity, homogeneity and dose gradient index. All these parameters could be included in the Unified Dosimetry Index (UDI). We developed a global UDI (gUDI) to evaluate treatment plans containing volumes irradiated with different dose prescriptions: Intensity Modulated Radiation Therapy with simultaneous integrated boost IMRT-SIB with 2 dose levels (36.25 Gy/5 fz for the whole prostate gland and 37.5 Gy/5 fz for Dominant Intraprostatic Lesion (DIL)). gUDI score equals to one for an ideal plan. To validate gUDI scoring system, 65 prostate cancer patients treated with ultra-hypofractionated IMRT-SIB using VMAT technique were evaluated. The computation of gUDI index was performed separately for plans with single or double DIL. Mean (μ) and standard deviations (σ) were calculated for all dosimetry indices and gUDI. Furthermore, gUDI μ and σ were analyzed to compare and classify treatment plans: under this ranking system, plans can be ranked as "excellent", "good", "average" or "poor". Results Dose Coverage and Homogeneity index scores did not get away from the ideal values, both for the prostate and DIL. No statistical differences were founded for plans with single or double DIL. The gUDI index classification showed only 6 cases in the "poor" region and most of the plans scored as "average" and "good". Conclusions gUDI score can be a useful tool to quantify treatment plans quality also when different dose prescriptions volumes are treated. Furthermore, gUDI allows to establish a standard on which dosimetry plans can be ranked. [ABSTRACT FROM AUTHOR]

This study investigated the xylanases produced by Trichoderma piluliferum and T. viride. These enzymes were characterized and used as additives in bovine diet. The fungus T. piluliferum was a more efficient producer of xylanase (301 U g−1 dry substrate) when grown on wheat bran, with 75 or 80% moisture for 96 h. The optimum pH of the enzyme produced by T. piluliferum was 4.5, obtaining as the optimum temperature 50 °C. The enzyme was stable at a wide pH range (3.0–10.0), and it remained stable for 1 h at 40 °C. The best culture parameters for the cultivation of T. viride (671 U g−1 dry substrate) were as follows: wheat bran as substrate, 65, 70 and 75% initial moisture, and 48 h cultivation time. The optimum pH and temperature for the xylanase produced by this fungus were 6.0 and 45 °C, respectively, and the enzyme was stable at a wide pH range (3.0–10.0), maintaining its activity after 1 h at 40 °C. Both the enzyme extracts produced were effective at increasing digestibility of Tifton 185 hay, sugarcane silage, and corn silage. The enzymatic extracts proved promising for xylooligosaccharides production and showed low cellulase activity, indicating potential for application in biobleaching processes of cellulose pulp and paper. • Xylanases production by Trichoderma piluliferum and Trichoderma viride. • Catalytic properties of the enzymatic extracts. • Catalytic profile of the xylanases by thin layer chromatography (TLC). • Application of the enzymatic extracts as additives in bovine diet. [ABSTRACT FROM AUTHOR]

Abstract Purpose To evaluate interplay effect on delivered dose distributions for lung cancer treatments using treatment techniques (DynamicWaveArc [1,2] , DynamicConformalArc and DynamicTumorTracking) performed with VERO system. Methods For each patient with lung nodules selected for stereotactic treatments a 4DCT with RPM Varian System was acquired. Internal Target Volume (ITV) was created on maximum intensity projection reconstructed from a dataset of ten phases and enlarged to PTV (5 mm margins). For each plan an extreme hypo-IGRT schedule was applied (36 Gy/3fz) with a prescription of D95% PTV = 100%. DWA planning was performed with Collapsed Cone Convolution Superposition on Raystation (v.6.1.1.2) (2 full arcs, GenericX1 template), while DCA and DTT with Monte Carlo algorithm on iPlannet RT Dose (v.4.5.4) (1 full arc and 5 conformal beams, respectively). Plans were recalculated as pre-treatment QA and delivered on BrainLab Respiratory Gating Phantom, applying real patients' breathing patterns. Dose maps were acquired with EBT3 Gafchromic, applying a single scan protocol for absolute dose measurements [3,4]. All films were read with an EPSON XL10000 scanner in transmission mode (48-bit RGB and 72 dpi resolution) and analyzed with FilmQAPro® 2016 (Ashland). For each technique, absolute dose γ analysis was performed between static and moving delivery, applying 2%-2 mm criteria and no dose threshold. Evaluations were performed considering single and 3-fractions schedule and a mean γ passing rate for 5 patients. Results Results obtained from analysis of all treatment techniques and both schedules are reported in Table 1. Conclusions From preliminary studies, the interplay effect is more pronounced in DWA treatments than in other cases, as expected. However as the number of fractions is increased, the γ passing rates become almost acceptable also for DWA. We also started to investigate the interplay effect varying patients' breathing patterns [5]. Results suggest using this technique for moving targets could lead to better OARs sparing. [ABSTRACT FROM AUTHOR]