factors influencing acute and late toxicity in the era of adjuvant hypofractionated breast radiotherapy

Abstract Purpose To evaluate toxicity in breast cancer patients treated with anthracycline and taxane based chemotherapy and whole breast hypofractionated radiotherapy, and to identify the risk factors for toxicity. Methods and materials 537 early breast cancer patients receiving hypofractionated radiotherapy after conservative surgery were enrolled from April 2009 to December 2014, in an Italian cancer institute. The dose was 42.4 Gy in 16 daily fractions, 2.65 Gy per fraction. The boost to the tumor bed was administered only in grade III breast cancer patients and in patients with close or positive margins. Acute and late toxicity were prospectively assessed during and after radiotherapy according to RTOG scale. The impact of patients clinical characteristics, performed treatments and dose inhomogeneities on the occurrence of an higher level of acute skin toxicity and late fibrosis has been evaluated by univariate and multivariate analysis. Results The mean age was 74 (range 46–91 yrs). 27% of patients received boost. 22% of cases (n = 119) received also chemotherapy. The median follow-up was 32 months. G1 and G2/G3 acute skin toxicity were 61.3% and 20.5% and G1 and G2/G3 late fibrosis 12.6% and 4.3% respectively. Chemotherapy (p = 0.04), diabetes (p = 0.04) and boost administration (p Conclusions The results of our study, according to the large randomized trials, confirmed that hypofractionated whole breast irradiation is safe, and only the boost administration seems to be an important predictor for toxicity. Chemotherapy does not impact on acute and late skin toxicity

Set-up to design guidance for the Crablock armour unit

The Crablock is a symmetrical unit, this in contrast to the units that have been applied most in the past. Essentially, this is the main difference. All other units have six \u93obstacles\u94 that insure interlocking, but they are not symmetrical. All those units are placed randomly in a certain way with more or less contacts to neighbouring units. A symmetrical unit may give the opportunity to place the units in a more or less rectangular pattern. This may ease the construction requirements. It may also have influence on stability, where the expectation is that it could be more stable than a random placement. Uniform placement may, however, increase the packing density (number of units per square meter) and/or wave overtopping. But at least one can say that the Crablock can distinguish itself from the well-known units by the symmetrical shape. The main objectives of this report are: 1) outline the recommendations for a fast and efficient approach to come to a design guidance; 2) establish what design parameters are most important for the new single layer armour unit investigation, such as the placing pattern, the crest height, the settlement, etc. 3) identify what kind of tests should be done for Crablock in a wave flume.Crabloc

Dal mondo nuovo alla città infinita: cento anni di trasfomazioni e progetti nell’area milanese

Volume n. 8 della collana Argomenti e Contributi

A Comparative Study Between Bio-composites Obtained with Opuntia ficus indica Cladodes and Flax Fibers

This work is aimed to study the suitability of the wooden backbone of Opuntia ficus indica cladodes as reinforcement for the production of bio-composites. The wooden backbone can be extracted from O. ficus indica cladodes, which constitute a very relevant agricultural scrap, and is characterized by a thick walled cellular structure. In view of its potential in poly-lactic acid (PLA) matrix bio-composite production, two different possible applications were examined. In the first alternative, the wooden backbone was used in replacement of flax fibers for the production of fully consolidated bio-composites. Results obtained have shown that, though being characterized by lower properties compared to those of flax fiber composites, the opuntia actually works as an efficient reinforcement for PLA/wood flour matrix, increasing the flexural strength and elongation at break. In the second alternative, the cellular structure was used for the production of a sandwich bio-composite with a PLA/wood flour skin. In this case, the very high interlaminar adhesion strength between the skin and the core was considered as an indication of the potentiality of this material for the production of high strength sandwich structures. As a confirmation of this, no interlaminar debonding was observed during short beam tests

ABDUCTIVE INFERENCES IN PRAGMATIC PROCESSES

Abstract In pragmatic theories, the notion of inference plays a central role, together with the communicative act in which it is activated. Although some scholars, such as Levinson, Sperber and Wilson, propose detailed and accurate analyses of this notion, we will maintain that these analyses can be better systematized if seen through Peirce\u2019s notion of abduction. We will try to maintain that the variety of inferential processes in play in a linguistic act is mostly of an abductive nature. Moreover, we will maintain that the typological tripartition of abductions discussed by Eco (1981) allows to account for a signi cant part of the mechanisms involved in the comprehension of an utterance, ranging from quasi-immediate and spontaneous levels of understanding to processes that draw on creative resources. In our proposal the vast majority of our linguistic activities implies the automatic retrieval of a habit of action (automatic abduction). In the other cases we need more onerous processes. We might need to identify, among a range of possibilities, the appropriate rule (habit of action/linguistic routine) to be applied to the contextual situation (abduction by selection) or, depending on the context and on our background knowledge, we might be forced to create ex novo a new linguistic routine (creative abduction). In our view, this typology of abductive inferences (Eco, 1981; see also Bonfantini and Proni, 1980) provides us with all the necessary tools to account for the different inferential demands entailed by different levels of the process of lan-guage comprehension. On the basis of this typology we can, develop a finne-grained model of linguistic inferences and, thus, simplify the terms of some problematic nodes debated within contextualist approaches

Application of failure mode and effects analysis to optimization of linac quality controls protocol

Purpose: To apply Failure Mode and Effects Analysis (FMEA) to optimize linac quality control (QC) protocol in order to ensure patient safety and treatment quality, taking maximum advantage of the available resources. Material and methods: Each parameter tested by the QC was considered as a potential failure mode (FM). For each FM, likelihood of occurrence (O), severity of effect (S), and lack of detectability (D) were evaluated and corresponding Risk Priority Number (RPN) was calculated from the product of three indexes. The scores were assigned using two methods: (a) A survey submitted to the medical physicists; (b) A semi-quantitative analysis (SQA) performed through: simulation of FMs in the treatment planning system; studies reported in literature; results obtained by the QC data analysis. A weighted RPN for all FMs was calculated taking into account both the methods. For each linac, the tests were then sorted by their frequency and the RPN value. Results: A high variability was found in the scores of the survey, although in many it was reduced in RPN values, highlighting the more relevant tests as on beam output and imaging system. Integrating these results with those obtained by SQA, the RPN-based ranking of tests has been provided considering the specific use of the accelerator: for example, more accurate tests on dose modulation and multileaf collimator speed were required in linacs where intensity-modulated treatment is performed, while, more specific tests on couch and jaw position indicators were necessary where treatments with multiple isocenters and/or junctions between adjacent fields were often delivered. Conclusions: Failure Mode and Effects Analysis is a useful tool to prioritize the linac QCs, taking into account the specific equipment and clinical practice. The integration of SQA and survey results reduces subjectivity of the FMEA scoring and allows to optimize linac QCs without \u201closing\u201d the expertise and experience of medical physicists and clinical staff

Preemptive treatment with Xonrid®, a medical device to reduce radiation induced dermatitis in head and neck cancer patients receiving curative treatment: a pilot study

Purpose: The purpose of this study was to investigate efficacy, safety and tolerability of Xonrid®, a new medical device, in preventing radiation dermatitis associated with head and neck cancer (HNC) radiotherapy (RT). Methods: In this monocentric, prospective pilot study, adult consecutive HNC patients who were planned to receive curative RT with or without chemotherapy were enrolled. Patients were instructed to apply Xonrid® on the irradiated area during treatment continuing until 2 weeks after the completion of RT or the development of severe skin toxicity. Toxicity was assessed using the Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 scale. The patient reported outcome measures included the Skindex-16 questionnaire and patient satisfaction. Skin reflectance spectra were analyzed to objectively evaluate dermatitis. Results: In total, 41 subjects were enrolled (30 males, median age 60 years). No skin adverse events were recorded either in the skin area where the product was applied or in the nearby skin over the entire period of administration. At the end of RT, nine patients (22%) presented G1, 31 (76%) G2, and one patient (2%) G3 skin toxicity (after 5 weeks). Seven and 20 patients reached skin maximum toxicity at the fourth week and after the seventh week, respectively. An increasing trend of median spectrophotometry scores along with skin toxicity grades was observed. A correlation between Skindex-16 scores and skin toxicity grade during treatment was found. Conclusions: Our study results suggest that Xonrid® is well tolerated, safe, and effective in minimizing and delaying high-grade radiation dermatitis in HNC patients