Impact of different optimization strategies on the compatibility between planned and delivered doses during radiation therapy of cervical cancer

PurposeTo analyse the impact of different optimization strategies on the compatibility between planned and delivered doses during radiotherapy of cervical cancer.Material/methodsFour treatment plans differing in optimisation strategies were prepared for ten cervical cancer cases. These were: volumetric modulated arc therapy with (_OPT) and without optimization of the doses in the bone marrow and for two sets of margins applied to the clinical target volume that arose from image guidance based on the bones (IG(B)) and soft tissues (IG(ST)). The plans were subjected to dosimetric verification by using the ArcCHECK system and 3DVH software. The planned dose distributions were compared with the corresponding measured dose distributions in the light of complexity of the plans and its deliverability.ResultsThe clinically significant impact of the plans complexity on their deliverability is visible only for the gamma passing rates analysis performed in a local mode and directly in the organs. While more general analyses show statistically significant differences, the clinical relevance of them has not been confirmed. The analysis showed that IG(ST)_OPT and IG(B)_OPT significantly differ from IG(ST) and IG(B). The clinical acceptance of IG(ST)_OPT obtained for hard combinations of gamma acceptance criteria (2%/2 mm) confirm its satisfactory deliverability. In turn, for IG(B)_OPT in the case of the rectum, the combination of 2%/2 mm did not meet the criteria of acceptance.ConclusionDespite the complexity of the IG(ST)_OPT, the results of analysis confirm the acceptance of its deliverability when 2%/2 mm gamma acceptance criteria are used during the analysis

Currently used in clinical practice beam rate changes have no significant effect on the reduction of clonogenic capacity of PNT1A cells in vitro

Background: Due to the lack of selectivity of ionizing radiation between normal and cancer cells, it is important to improve the existing radiation patterns. Lowering the risk of cancer recurrence and comfort during treatment are priorities in radiotherapy. Materials and methods: In the experiment we used dose verification to determine the irradiation time calculated by a treatment planning system for 6XFFF and 10XFFF beams. Cells cultured under standard conditions were irradiated with a dose of 2 Gy at different beam rates 400 MU/min, 600 MU/min, 800 MU/min, 1000 MU/min, 1400 MU/min,  1600 MU/min and 2400 MU/min using 6XFFF, 10XFFF and 6XFF beams. Results: The experiment was aimed at comparing the biological response of normal prostate cells after clinically applied radiation patterns. No statistically significant differences in the cellular response were observed. The wide range of beam rates as well as the beam profiles did not significantly affect cell proliferation. Conclusions: High beam rates, without significantly affecting the clonogenic capacity of cells, have an impact on the quality of patient's treatment. With the increasing beam rate the irradiation time is shortened, which has an important impact on patients’ health. This experiment can have a practical significance

Verification of electron beam parameters in an intraoperative linear accelerator using dosimetric and radiobiological response methods

Background: The availability of linear accelerators (linac) for research purposes is often limited and therefore alternative radiation sources are needed to conduct radiobiological research. The National Centre for Radiation Research in Poland recently developed an intraoperative mobile linac that enables electron irradiation at energies ranging from 4 to 12 MeV and dose rates of 5 or 10 Gy/min. The present study was conducted to evaluate the electron beam parameters of this intraoperative linac and to verify the set-up to evaluate out-of-field doses in a water phantom, which were determined through dosimetric and biological response measurements. Materials and methods: The distribution of radiation doses along and across the radiation beam were measured in a water phantom using a semiconductor detector and absolute doses using an ionisation chamber. Two luminal breast cancer cell lines (T-47D and HER2 positive SK-BR-3) were placed in the phantom to study radiation response at doses ranging from 2 to 10 Gy.  Cell response was measured by clonogenic assays. Results and Conclusion: The electron beam properties, including depth doses and profiles, were within expected range for the stated energies. These results confirm the viability of this device and set-up as a source of megavoltage electrons to evaluate the radiobiological response of tumour cells

Results of the IROCA international clinical audit in prostate cancer radiotherapy at six comprehensive cancer centres

To assess adherence to standard clinical practice for the diagnosis and treatment of patients undergoing prostate cancer (PCa) radiotherapy in four European countries using clinical audits as part of the international IROCA project. Multi-institutional, retrospective cohort study of 240 randomly-selected patients treated for PCa (n = 40/centre) in the year 2015 at six European hospitals. Clinical indicators applicable to general and PCa-specific radiotherapy processes were evaluated. All data were obtained directly from medical records. The audits were performed in the year 2017. Adherence to clinical protocols and practices was satisfactory, but with substantial inter-centre variability in numerous variables, as follows: staging MRI (range 27.5-87.5% of cases); presentation to multidisciplinary tumour board (2.5-100%); time elapsed between initial visit to the radiation oncology department and treatment initiation (42-102.5 days); number of treatment interruptions ≥ 1 day (7.5-97.5%). The most common deviation from standard clinical practice was inconsistent data registration, mainly failure to report data related to diagnosis, treatment, and/or adverse events. This clinical audit detected substantial inter-centre variability in adherence to standard clinical practice, most notably inconsistent record keeping. These findings confirm the value of performing clinical audits to detect deviations from standard clinical practices and procedures

Improving radiation oncology through clinical audits: Introducing the IROCA project

As radiotherapy practice and processes become more complex, the need to assure quality control becomes ever greater. At present, no international consensus exists with regards to the optimal quality control indicators for radiotherapy; moreover, few clinical audits have been conducted in the field of radiotherapy. The present article describes the aims and current status of the international IROCA “Improving Radiation Oncology Through Clinical Audits” project. The project has several important aims, including the selection of key quality indicators, the design and implementation of an international audit, and the harmonization of key aspects of radiotherapy processes among participating institutions. The primary aim is to improve the processes that directly impact clinical outcomes for patients. The experience gained from this initiative may serve as the basis for an internationally accepted clinical audit model for radiotherapy

IROCA-TES: Improving Quality in Radiation Oncology through Clinical Audits — Training and Education for Standardization

Background: Clinical audits are an important tool to objectively assess clinical protocols, procedures, and processes and to detect deviations from good clinical practice. The main aim of this project is to determine adherence to a core set of consensus-based quality indicators and then to compare the institutions in order to identify best practices. Materials and methods: We conduct a multicentre, international clinical audit of six comprehensive cancer centres in Poland, Spain, Italy, Portugal, France, and Romania as a part of the project, known as IROCATES (Improving Quality in Radiation Oncology through Clinical Audits — Training and Education for Standardization). Results: Radiotherapy practice varies from country to country, in part due to historical, economic, linguistic, and cultural differences. The institutions developed their own processes to suit their existing clinical practice. Conclusions: We believe that this study will contribute to establishing the value of routinely performing multi-institutional clinical audits and will lead to improvement of radiotherapy practice at the participating centres

EPID-based daily verification of reproducibility of patients’ irradiation with IMRT plans

AimThe aim of the work was to catch potential errors with daily EPID measurements of repeatability of the dose distribution during irradiation of IMRT patients.Materials and methodsIn the first stage, measurements were made using an anthropomorphic phantom in which the method of collecting data with an EPID device and the possibility of detecting errors in positioning were developed. Next, for 23 patients, the pelvis (P) and head and neck (H&N) regions, images were collected with an EPID device for each IMRT subfield daily and compared to reference images using the gamma method (DTA 3mm, DD 3%). Finally, the dependencies between treatment plan parameters, pre-verification results and repeatability of collected images were evaluated.ResultsThe anthropomorphic phantom study has shown what kind of effects we can expect with EPID measured at potential shifts during radiotherapy. For the clinical case, score results were obtained for individual tumor regions as below: (P) 0.786±1.046, (H&N) 0.720±1.552. For most evaluated cases, score values were below 1%: (P) 75.5% and (H&N) 83.9% of analyzed fields. 95% of all evaluated data was with the score below: (P) 2.86% and (H&N) 3.40%. The relationship between the results of the analysis of daily collected images and the results of pre-verification, field size and irradiation time was shown.ConclusionsThe EPID-based daily verification can provide extra information about day-to-day repeatability of treatment, without additional dose

Indirect self-destructiveness of persons after suicide attempted

Wstęp. Zjawisko szkodzenia samemu sobie jest znane od dawna. W literaturze psychologicznej pojęcie autodestruktywności występuje w 3 znaczeniach: w opisie zachowania, w określeniu jego skutków oraz w odniesieniu do hipotetycznych wewnętrznych mechanizmów wyjaśniających to zachowanie. Rozróżnia się zagrożenie i/lub szkodę bezpośrednią (autodestruktywność bezpośrednia) oraz pośrednią (autodestruktywność pośrednia). Specyficzną formą autodestruktywności bezpośredniej (ze względu na powagę, a często też nieodwracalność skutków) jest samobójstwo. Celem niniejszej pracy było zbadanie syndromu autodestruktywności pośredniej u osób po próbach samobójczych. Materiał i metody. Badaniami objęto 98 osób po próbach samobójczych w wieku 14-33 lat. Zastosowano Skalę Autodestruktywności Pośredniej, czyli polską wersję Chronic Self-Destructiveness Scale (CS-DS) Kelley, w adaptacji Suchańskiej. Wyniki. Stwierdzono, że wyniki osób po próbach samobójczych dotyczące autodestruktywności pośredniej jako uogólnionej tendencji mieszczą się w górnej granicy przedziału wyników średnich, mimo opieki specjalistycznej. Wyniki uzyskane przez badanych w CS-DS wyglądają następująco (kolejność wg nasilenia danej kategorii): Bezradność i bierność wobec trudności (A5), Transgresja i ryzyko (A1), Zaniedbania zdrowotne (A2), Zaniedbania osobiste i społeczne (A3) oraz Nieuważność, nieostrożność i brak planowania (A4). Analizując zjawisko autodestruktywności pośredniej w różnych grupach wiekowych, stwierdzono, że badani w wieku 14-17 lat w niemal wszystkich kategoriach zachowań pośrednio autodestruktywnych uzyskali istotnie wyższe wyniki niż osoby w wieku 18–33 lat. Wnioski. Wysokie wskaźniki przejawów autodestruktywności pośredniej u pacjentów po próbach samobójczych świadczą, zwłaszcza u nieletnich i młodocianych, o utrzymującym się ryzyku ponownego zamachu na swoje życie i stanowią istotny element zespołu presuicydalnego.Background. The phenomenon of self-harm has been known for a long time; in the psychological literature the concept of self-destructiveness is used in three meanings: in the description of behaviour, in description of behavioural consequences, and referring to hypothetical inner mechanisms underlying such behaviours. A distinction is made between direct and indirect threat and/or harm (direct and indirect self-destructiveness, respectively). Due to the severity and often irreversibility of its consequences, suicide is regarded as a specific form of direct self-destructiveness. The aim of this paper was to investigate the syndrome of indirect self-destructiveness in persons after suicide attempts. Material and methods. Participants in the study were 98 persons aged 14-33, who had attempted suicide. They were examined using the Kelley Chronic Self-Destructiveness Scale (CSDS) in the Polish adaptation by Suchańska. Results: The scores of persons after suicide attempts on the indirect self-destructiveness as a generalized tendency approached the upper limit of the average range, despite specialist care they received. They scored on the CSDS scales as follows (categories in descending order): Helplessness and passivity (A5), Transgression and risk (A1), Poor health maintenance (A2), Carelessness (A3) and Lack of planfulness (A4). A comparison of different age groups indicated that persons in the 14-17 age range scored in almost all categories of indirectly self-destructive behaviour significantly higher than did those aged 18–33 years. Conclusions: The high levels of indirect self-destructiveness symptoms in persons after suicide attempts, especially in minors and adolescents, are an evidence of a persistent risk of repeat suicide attempt and constitute an important element of the presuicidal syndrome

The Effectiveness of Selected Devices to Reduce the Speed of Vehicles on Pedestrian Crossings

Accidents involving pedestrians often result in serious injury or death. The main goal of this conducted research is to evaluate selected devices that will help reduce the speed of vehicles on pedestrian crossings. Many devices from a group of “speed control measures” and “mid block tools” (refugee islands, speed tables, and raised pedestrian crossings) are examined to find the most effective ones. In our research, the range of reduction of a vehicle’s speed is used as a main measure of effectiveness, but a wider statistical analysis was conducted as well. One of the results of the research is the identification of three categories of devices referred to as high effectives (good), medium effectives (intermediate), and low or lack of effectives (bad). The content of the paper starts by highlighting the reasons to reduce the vehicle’s speed on pedestrian crossings (as an introduction). Next, we present the description of devices used to reduce the vehicle’s speed with a presentation of the research of their effectiveness. The studies that have been conducted are described in the following chapters: first, the characteristic of method and location, second, with discussion, the results of research and identification of the three categories of devices. The paper is then summarized by conclusions and comments. The research only covered the issues of road traffic engineering. The research was made in Poland, but the conclusions could be useful worldwide due to similar traffic rules and technical solutions

Manifestations of indirect self-destructiveness in persons after suicide attempts

Objective: To explore the indirect self-destructiveness syndrome and its manifestations in persons after suicide attempt. Material and methods: The study population consisted of 147 persons (114 women and 33 men) aged 14-33 years. The control group was selected from among persons who did not commit suicide, well-matched in terms of sociodemographic status. To study the indirect self-destructiveness and its manifestations the Polish version of the Chronic Self- Destructiveness Scale (CS-DS) by K. Kelley in Suchańska adaptation was used. Results: Patients after suicide attempts gained significantly higher scores than those who did not commit suicide, in all indices of CS-DS: indirect self-destructiveness global index, A1: Transgression and Risk, A2: Poor Health Maintenance, A3: Personal and Social Neglects, A4: Lack of Planfulness, A5: Helplessness and Passiveness. People after suicide attempts gained significantly higher scores in the active as well as in the passive form of indirect self-destructiveness. Conclusions: The index of indirect self-destructiveness syndrome in patients after suicide attempts is within the upper limit of the average scores. The dominant classes of indirect self-destructive behaviours are (order according to intensity): Helplessness and Passiveness (A5), Transgression and Risk (A1), Poor Health Maintenance (A2). Intensiveness of indirect self-destructiveness as a generalized tendency is higher than in persons without suicide attempts. Intensity of particular categories (classes, manifestations) of indirect self-destructiveness is also higher in them. The intensity of active and passive form in these persons is almost identical, while in persons without suicide attempts, the intensiveness of the active form is much lower than the passive one’s. Results of research on indirect self-destructiveness may be useful in the suicidal prevention and in therapeutic work with persons who have attempted suicide.Cel: Zbadanie syndromu autodestruktywności pośredniej i jej przejawów u osób, które dokonały próby samobójczej. Materiał i metoda: Populacja badana składała się ze 147 osób (114 kobiet i 33 mężczyzn) w wieku 14-33 lat. Grupę porównawczą utworzono spośród osób, które nie podejmowały prób samobójczych; była ona dopasowana pod względem statusu socjodemograficznego. Do badania autodestruktywności pośredniej i jej przejawów zastosowano polską wersję Chronic Self-Destructiveness Scale (CS-DS) K. Kelley w adaptacji Suchańskiej. Wyniki: Osoby po próbach samobójczych uzyskały wyniki istotnie wyższe niż osoby, które nie podejmowały prób samobójczych, we wszystkich wskaźnikach CS-DS: globalny wskaźnik autodestruktywności pośredniej, A1: Transgresja i Ryzyko, A2: Zaniedbania Zdrowotne, A3: Zaniedbania Osobiste i Społeczne, A4: Nieuważność i Brak Planowania, A5: Bezradność i Bierność. Osoby po próbach samobójczych uzyskały wyniki istotnie wyższe w formie aktywnej, jak również w formie biernej autodestruktywności pośredniej. Wnioski: Wskaźnik syndromu autodestruktywności pośredniej u osób po próbach samobójczych mieści się w górnej granicy wyników średnich. Dominującymi klasami zachowań pośrednio autodestruktywnych są u nich (w kolejności natężenia): Bezradność i Bierność (A5), Transgresja i Ryzyko (A1), Zaniedbania Zdrowotne (A2). Nasilenie autodestruktywności pośredniej jako tendencji uogólnionej jest większe niż u osób bez prób samobójczych. Nasilenie poszczególnych kategorii (klas, przejawów) autodestruktywności pośredniej również jest u nich większe. Nasilenie formy aktywnej i biernej u tych osób jest prawie identyczne, natomiast u osób bez prób samobójczych nasilenie formy aktywnej jest o wiele niższe niż biernej. Wyniki badań nad autodestruktywnością pośrednią mogą być użyteczne w profilaktyce suicydalnej, a także w pracy terapeutycznej z osobami po próbach samobójczych