Overview of radiation oncology in the Czech Republic

BackgroundModern radiotherapy (RT) plays a very important role in both curative and palliative treatment of tumours. There are large variations among the EU countries and even regional variations within countries in the provision of RT.AimIn this report we present an overview of the current infrastructure, organisation, education and quality programme of radiotherapy in the Czech Republic.Material and MethodsData from the National Cancer Registry, Institute of Health Information and Statistics of the Czech Republic and from questionnaires and clinical audits of radiotherapy departments were used for evaluation of radiotherapy equipment, numbers of patients treated by radiotherapy and workload of radiotherapy facilities.ResultsRadiotherapy of malignant diseases is provided in 28 facilities in the Czech Republic. There are 35 linear accelerators and 16 cobalt units for the population of 10.3 million inhabitants, which represents one megavoltage unit for 200 000 inhabitants. Fourteen departments are equipped for brachytherapy with high dose rate afterloading machines. Forty-three percent of newly reported cancer patients undergo radiotherapy as part of oncological treatment.ConclusionThe main problem of radiation oncology in the Czech Republic is insufficient centralisation and the persistence of small, under-equipped departments

Imperfect 1-Out-of-2 Quantum Oblivious Transfer: Bounds, a Protocol, and its Experimental Implementation

Oblivious transfer is an important primitive in modern cryptography. Applications include secure multiparty computation, oblivious sampling, e-voting, and signatures. Information-theoretically secure perfect 1-out-of 2 oblivious transfer is impossible to achieve. Imperfect variants, where both participants' ability to cheat is still limited, are possible using quantum means while remaining classically impossible. Precisely what security parameters are attainable remains unknown. We introduce a theoretical framework for studying semi-random quantum oblivious transfer, which is shown equivalent to regular oblivious transfer in terms of cheating probabilities. We then use it to derive bounds on cheating. We also present a protocol with lower cheating probabilities than previous schemes, together with its optical realisation.Comment: 20 pages, 1 figur

Craniospinal irradiation of medulloblastoma in the supine position

BackgroundMedulloblastoma, a primitive neuroectodermal tumour growing in the cerebellum, is one of the most sensitive childhood brain tumours to radiation therapy. The most common malignant CNS tumour of children is medulloblastoma with an overall incidence among children aged 0–19 years of 16–20% of all paediatric brain tumours. Radiotherapy is an essential method of treatment for these tumours, but surgery is the primary treatment of choice in medulloblastoma. Postoperative radiation therapy has a significant impact on local control and overall survival.AimMedulloblastoma is the most common malignant brain tumour of children. The tumour is sensitive to chemotherapy and radiotherapy. Radiotherapy is an essential method of treatment for these tumours, but surgery is the primary treatment of choice in medulloblastoma.Materials/MethodsBetween January 1997 and March 2005 there were in this study post-operatively irradiated a total number of 33 paediatric patients aged under 15 years (median age 6.6 years) with medulloblastoma. All tumours were histologically proven and were located infratentorially in the posterior fossa. All of the patients were irradiated with a dose of 24–36 Gy to the whole craniospinal axis and boost with conformal therapy restricted to the tumour bed to the total dose of 50–54 Gy (30–36 Gy “high risk”, 24–30 Gy “standard risk” group). 26 patients (78%) received chemotherapy. Patients with craniospinal irradiation were placed in the supine position and fixed by a vacuum-form body immobilizer and head mask. Irradiation was performed using standard fractionation (5 fractions per week) with a single dose of 1.5–1.8 Gy for craniospinal axis by photon beam (6MV) of the linear accelerator.ResultsThe median overall survival for the whole group was 55.3 months. The median disease-free survival was 20.6 months. The overall survival rate at 5 years was 41%; 8 patients (24%) died. No relationship was found between survival and age, sex or tumour size. Endocrine deficits occurred in 30% (8 patients of the group were hypothyroid, growth retardation occurred in 7 patients).ConclusionsResults of overall and disease-free survival and side-effects of the technique of craniospinal axis irradiation in supine position are comparable with results of the technique in prone position

Breast cancer screening in the Czech Republic: time trends in performance indicators during the first seven years of the organised programme

<p>Abstract</p> <p>Background</p> <p>The Czech Breast Cancer Screening Programme (CBCSP) was initiated in September 2002 by establishing a network of accredited centres. The aim of this article is to describe progress in the programme quality over time after the inception of the organised programme.</p> <p>Methods</p> <p>The CBCSP is monitored using an information system consisting of three principal components: 1) the national cancer registry, 2) a screening registry collecting data on all screening examinations, further assessments and final diagnoses at accredited programme centres, and 3) administrative databases of healthcare payers. Key performance indicators from the European Guidelines have been adopted for continuous monitoring.</p> <p>Results</p> <p>Breast cancer incidence in the Czech Republic has steadily been increasing, however with a growing proportion of less advanced stages. The mortality rate has recently stabilised. The screening registry includes 2,083,285 records on screening episodes between 2002 and 2008. In 2007-2008, 51% of eligible women aged 45-69 were screened. In 2008, the detection rates were 6.1 and 3.7 per 1,000 women in initial and subsequent screening respectively. Corresponding recall rates are 3.9% and 2.2%, however, it is necessary to pay attention to further assessment performed during the screening visits. Benign to malignant open biopsy ratio was 0.1. Of invasive cases detected in screening, 35.6% was less than 10 mm in diameter. Values of early performance indicators, as measured by both crude and standardized estimates, are generally improving and fulfil desirable targets set by European Guidelines.</p> <p>Conclusions</p> <p>Mammography screening in the Czech Republic underwent successful transformation from opportunistic prevention to an organised programme. Values of early indicators confirm continuous improvement in different aspects of process quality. Further stimulation of participation through invitation system is necessary to exploit the full potential of screening mammography at the population level.</p

Detection and attribution of an anomaly in terrestrial photosynthesis in Europe during the COVID-19 lockdown

Carbon dioxide (CO2) uptake by plant photosynthesis, referred to as gross primary production (GPP) at the ecosystem level, is sensitive to environmental factors, including pollutant exposure, pollutant uptake, and changes in the scattering of solar shortwave irradiance (SWin) - the energy source for photosynthesis. The 2020 spring lockdown due to COVID-19 resulted in improved air quality and atmospheric transparency, providing a unique opportunity to assess the impact of air pollutants on terrestrial ecosystem functioning. However, detecting these effects can be challenging as GPP is influenced by other meteorological drivers and management practices. Based on data collected from 44 European ecosystem-scale CO2 flux monitoring stations, we observed significant changes in spring GPP at 34 sites during 2020 compared to 2015-2019. Among these, 14 sites showed an increase in GPP associated with higher SWin, 10 sites had lower GPP linked to atmospheric and soil dryness, and seven sites were subjected to management practices. The remaining three sites exhibited varying dynamics, with one experiencing colder and rainier weather resulting in lower GPP, and two showing higher GPP associated with earlier spring melts. Analysis using the regional atmospheric chemical transport model (LOTOS-EUROS) indicated that the ozone (O-3) concentration remained relatively unchanged at the research sites, making it unlikely that O-3 exposure was the dominant factor driving the primary production anomaly. In contrast, SWin increased by 9.4 % at 36 sites, suggesting enhanced GPP possibly due to reduced aerosol optical depth and cloudiness. Our findings indicate that air pollution and cloudiness may weaken the terrestrial carbon sink by up to 16 %. Accurate and continuous ground-based observations are crucial for detecting and attributing subtle changes in terrestrial ecosystem functioning in response to environmental and anthropogenic drivers

Altered energy partitioning across terrestrial ecosystems in the European drought year 2018

Drought and heat events, such as the 2018 European drought, interact with the exchange of energy between the land surface and the atmosphere, potentially affecting albedo, sensible and latent heat fluxes, as well as CO(2)exchange. Each of these quantities may aggravate or mitigate the drought, heat, their side effects on productivity, water scarcity and global warming. We used measurements of 56 eddy covariance sites across Europe to examine the response of fluxes to extreme drought prevailing most of the year 2018 and how the response differed across various ecosystem types (forests, grasslands, croplands and peatlands). Each component of the surface radiation and energy balance observed in 2018 was compared to available data per site during a reference period 2004-2017. Based on anomalies in precipitation and reference evapotranspiration, we classified 46 sites as drought affected. These received on average 9% more solar radiation and released 32% more sensible heat to the atmosphere compared to the mean of the reference period. In general, drought decreased net CO(2)uptake by 17.8%, but did not significantly change net evapotranspiration. The response of these fluxes differed characteristically between ecosystems; in particular, the general increase in the evaporative index was strongest in peatlands and weakest in croplands. This article is part of the theme issue 'Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'

Proceedings of the 13th annual conference of INEBRIA

CITATION: Watson, R., et al. 2016. Proceedings of the 13th annual conference of INEBRIA. Addiction Science & Clinical Practice, 11:13, doi:10.1186/s13722-016-0062-9.The original publication is available at https://ascpjournal.biomedcentral.comENGLISH SUMMARY : Meeting abstracts.https://ascpjournal.biomedcentral.com/articles/10.1186/s13722-016-0062-9Publisher's versio