CSF biomarkers of neurotoxicity in childhood cancer survivors after cranial radiotherapy or surgery.

OBJECTIVE: Treatment of pediatric brain tumors is associated with potential long-term cognitive sequelae. Patients treated with craniospinal irradiation for posterior fossa tumors are at high risk. New biomarkers that could help to differentiate treatment effects from other causes of cognitive dysfunction would be valuable in tailoring optimal survivorship care. Biomarkers that reflect biological mechanisms behind treatment-associated cognitive decline would also be important in the evaluation of future treatment regimens for pediatric brain or skull base tumors. METHODS: In this biomarker-finding study, 10 adult survivors of pediatric medulloblastoma, skull base tumors, and posterior fossa low-grade glioma underwent study specific lumbar puncture at a minimum of 17 years following treatment. We analyzed cerebrospinal fluid biomarkers reflecting neuron and astrocyte integrity, amyloid metabolism, inflammation, extracellular matrix, synaptic integrity, and blood-brain barrier function. The values were compared with biomarker levels in healthy controls of comparable age. RESULTS: Biomarkers reflecting neuronal injury (neurofilament light chain protein), astrocyte injury or activation (glial fibrillary acidic protein) as well as inflammation (YKL-40) were significantly elevated in cancer survivors compared to controls. Biomarkers reflecting amyloid metabolism showed a pattern of decrease in patients treated for medulloblastoma. INTERPRETATION: The results suggest a potential chronic low-grade neurodegeneration and astrocyte activation in patients treated for pediatric brain or skull base tumors. Protein biomarkers of CNS disease could potentially be used to increase our understanding of the contribution from different tumor treatments with regard to long-term symptoms in cancer patients.

Robustness and dosimetric verification of hippocampal-sparing craniospinal pencil beam scanning proton plans for pediatric medulloblastoma.

Background and Purpose: Hippocampal-sparing (HS) is a method that can potentially reduce late cognitive complications for pediatric medulloblastoma (MB) patients treated with craniospinal proton therapy (PT). The aim of this study was to investigate robustness and dosimetric plan verification of pencil beam scanning HS PT. Materials and Methods: HS and non-HS PT plans for the whole brain part of craniospinal treatment were created for 15 pediatric MB patients. A robust evaluation of the plans was performed. Plans were recalculated in a water phantom and measured field-by-field using an ion chamber detector at depths corresponding to the central part of hippocampi. All HS and non-HS fields were measured with the standard resolution of the detector and in addition 16 HS fields were measured with high resolution. Measured and planned dose distributions were compared using gamma evaluation. Results: The median mean hippocampus dose was reduced from 22.9 Gy (RBE) to 8.9 Gy (RBE), while keeping CTV V95% above 95 % for all nominal HS plans. HS plans were relatively robust regarding hippocampus mean dose, however, less robust regarding target coverage and maximum dose compared to non-HS plans. For standard resolution measurements, median pass rates were 99.7 % for HS and 99.5 % for non-HS plans (p < 0.001). For high-resolution measurements, median pass rates were 100 % in the hippocampus region and 98.2 % in the surrounding region. Conclusions: A substantial reduction of dose in the hippocampus region appeared feasible. Dosimetric accuracy of HS plans was comparable to non-HS plans and agreed well with planned dose distribution in the hippocampus region.

Kilohertz serial crystallography with the JUNGFRAU detector at a fourth-generation synchrotron source.

Serial and time-resolved macromolecular crystallography are on the rise. However, beam time at X-ray free-electron lasers is limited and most third-generation synchrotron-based macromolecular crystallography beamlines do not offer the necessary infrastructure yet. Here, a new setup is demonstrated, based on the JUNGFRAU detector and Jungfraujoch data-acquisition system, that enables collection of kilohertz serial crystallography data at fourth-generation synchrotrons. More importantly, it is shown that this setup is capable of collecting multiple-time-point time-resolved protein dynamics at kilohertz rates, allowing the probing of microsecond to second dynamics at synchrotrons in a fraction of the time needed previously. A high-quality complete X-ray dataset was obtained within 1 min from lysozyme microcrystals, and the dynamics of the light-driven sodium-pump membrane protein KR2 with a time resolution of 1 ms could be demonstrated. To make the setup more accessible for researchers, downstream data handling and analysis will be automated to allow on-the-fly spot finding and indexing, as well as data processing.

A scoping review of older patients' health-related quality of life, recovery and well-being after intensive care.

AIMS: In the present study, we aimed to determine how Health-Related Quality of Life (HRQoL), recovery (function and capacity in daily life) and well-being are followed up and characterised in persons ≥65 years of age who were being cared for in an intensive care unit (ICU). DESIGN: A scoping review. METHODS: CINAHL, MEDLINE (Ovid) and PsycINFO databases were searched in October 2021. 20 studies met the inclusion criteria. The scoping review followed the principles outlined by Arksey and O'Malley, and the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) checklist and Joanna Briggs Institute (JBI) framework were used. RESULTS: Results are presented under five subheadings: Study characteristics, Type of studies, Methods for follow-up, health-related quality of life, and Recovery. Time seems to be an important factor regarding HRQoL among older patients being cared for in an ICU, with most elderly survivors perceiving their HRQoL as acceptable after 1 year. Nevertheless, several studies showed patients' willingness to be readmitted to the ICU if necessary, indicating that life is worth fighting for. PATIENT OR PUBLIC CONTRIBUTION: Due to the design of the study, this study involves no patient or public contribution.

The risk of radiation-induced neurocognitive impairment and the impact of sparing the hippocampus during pediatric proton cranial irradiation.

BACKGROUND AND PURPOSE: Hippocampus is a central component for neurocognitive function and memory. We investigated the predicted risk of neurocognitive impairment of craniospinal irradiation (CSI) and the deliverability and effects of hippocampal sparing. The risk estimates were derived from published NTCP models. Specifically, we leveraged the estimated benefit of reduced neurocognitive impairment with the risk of reduced tumor control. MATERIAL AND METHODS: For this dose planning study, a total of 504 hippocampal sparing intensity modulated proton therapy (HS-IMPT) plans were generated for 24 pediatric patients whom had previously received CSI. Plans were evaluated with respect to target coverage and homogeneity index to target volumes, maximum and mean dose to OARs. Paired t-tests were used to compare hippocampal mean doses and normal tissue complication probability estimates. RESULTS: The median mean dose to the hippocampus could be reduced from 31.3 GyRBE to 7.3 GyRBE (p < .001), though 20% of these plans were not considered clinically acceptable as they failed one or more acceptance criterion. Reducing the median mean hippocampus dose to 10.6 GyRBE was possible with all plans considered as clinically acceptable treatment plans. By sparing the hippocampus to the lowest dose level, the risk estimation of neurocognitive impairment could be reduced from 89.6%, 62.1% and 51.1% to 41.0% (p < .001), 20.1% (p < .001) and 29.9% (p < .001) for task efficiency, organization and memory, respectively. Estimated tumor control probability was not adversely affected by HS-IMPT, ranging from 78.5 to 80.5% for all plans. CONCLUSIONS: We present estimates of potential clinical benefit in terms of neurocognitive impairment and demonstrate the possibility of considerably reducing neurocognitive adverse effects, minimally compromising target coverage locally using HS-IMPT.

Automated data extraction tool (DET) for external applications in radiotherapy.

Oncological Information Systems (OIS) manage information in radiotherapy (RT) departments. Due to database structure limitations, stored information can rarely be directly used except for vendor-specific purposes. Our aim is to enable the use of such data in various external applications by creating a tool for automatic data extraction, cleaning and formatting. METHODS AND MATERIALS: We used OIS data from a nine-linac RT department in Sweden (70 weeks, 2015-16). Extracted data included patients' referrals and appointments with details for RT sub-tasks. The data extraction tool to prepare the data for external use was built in C# programming language. It used excel-automation queries to remove unassigned/duplicated values, substitute missing data and perform application-specific calculations. Descriptive statistics were used to verify the output with the manually prepared dataset from the corresponding time period. RESULTS: From the initial raw data, 2030 (51 %)/907 (23 %) patients had known curative and palliative treatment intent for 84 different cancer diagnoses. After removal of incomplete entries, 373 (10 %) patients had unknown treatment intents which were substituted based on the known curative/palliative ratio. Automatically- and manuallyprepared datasets differed < 1 % for Mould, Treatment planning, Quality assurance and ± 5 % for Fractions and Magnetic resonance imaging with overestimations in 80/140 (57 %) entries by the tool. CONCLUSION: We successfully implemented a software tool to prepare ready-to-use OIS datasets for external applications. Our evaluations showed overall results close to the manually-prepared dataset. The time taken to prepare the dataset using our automated strategy can reduce the time for manual preparation from weeks to seconds.

Mortality Among Pediatric Patients With Acute Lymphoblastic Leukemia in Sweden From 1988 to 2017.

Importance: Acute lymphoblastic leukemia (ALL) constitutes 20% to 30% of all pediatric cancers. The 5-year overall survival among pediatric patients with ALL in high-income countries such as Sweden is currently more than 90%, but long-term unselected nationwide mortality data and mortality data in relation to the general population are lacking. Objective: To compare mortality between pediatric patients with ALL and the general population during a 30-year period in Sweden and to assess the incidence of ALL in Sweden. Design, Setting, and Participants: This cohort study included pediatric patients (aged <18 years) with a morphologically verified ALL diagnosis in the Swedish Cancer Register and/or at least 2 ALL diagnoses in the Swedish National Patient Register between January 1, 1988, and December 31, 2017. Data were cross-linked to the Swedish Cause of Death Register. Data were analyzed from May 2019 to January 2022. Main Outcomes and Measures: The main outcomes were mortality among patients with ALL compared with that in the general population and mortality in different subgroups within the cohort. Standardized mortality ratios (SMRs) were calculated using the general Swedish population as a reference. Within-cohort survival analyses were performed. Results: A total of 2397 patients (1354 [56%] male; mean [SD] age at diagnosis, 6.1 [4.7] years) were included in the study. The mean (SD) incidence of pediatric ALL during the study period was 4.11 (0.60) cases per 100 000 persons per year (females, 3.68 [0.65] cases per 100 000 persons per year; males, 4.52 [0.81] cases per 100 000 persons per year; P < .001). The observed number of deaths among pediatric patients with ALL was 409 vs the 9.5 deaths expected in the general population, resulting in an overall SMR of 43.1 (95% CI, 39.0-47.5); females had a higher SMR than males (57.8 [95% CI, 49.5-67.2] vs 34.5 [95% CI, 32.0-41.4]; P < .001). Analysis within the cohort showed a continued decrease in survival throughout the 30-year follow-up. The association between calendar year of ALL diagnosis, corresponding with different ALL treatment protocols, and mortality showed the lowest survival for the 1988-1991 group and the highest for the 2008-2017 group (χ2 = 20.3; P < .001). Conclusions and Relevance: In this cohort study, a consistently high SMR was seen among pediatric patients with ALL. Within the ALL cohort, survival evolved to a similar extent as in the young general population of Sweden. Furthermore, survival among patients with ALL decreased throughout the whole follow-up period without any trend difference after the 5-year follow-up time point. The changes in ALL treatment protocols were associated with overall improved absolute survival over time.

Referral of patients with cancer to palliative care: Attitudes, practices and work-related experiences among Swedish physicians.

OBJECTIVE: This study aimed to explore the attitudes, practices and work-related experiences among Swedish physicians regarding the referral process, integration and transition between oncology care and palliative care (PC). METHODS: A cross-sectional online survey was performed with a study-specific questionnaire in 2016-2017 in south-eastern Sweden. Physicians working with cancer patients within surgical specialties, medical specialties and paediatric oncology participated. RESULTS: The vast majority of the 130 participating physicians (99.2%) stated that PC was beneficial for the patient and were positive about early integration of PC (65.5%). Still, only 27.6% of the participants introduced PC at an early stage of non-curable disease. However, paediatric oncologists had a very early introduction of PC in comparison with medical specialties (p = 0.004). Almost 90% of the study population said they wanted to know that the patient had been taken care of by another care facility. CONCLUSIONS: Despite the physicians' positive attitude towards early integration and referral to PC, they often acted late in the disease trajectory. This late approach can reduce the patient's opportunity of improving quality of life during severe circumstances. There is a need for in-depth knowledge of the physicians' challenges in order to bridge the gap between intentions and actions.

Designing and Implementing a Population-based Organised Prostate Cancer Testing Programme.

BACKGROUND: European guidelines recommend that well-informed men at elevated risk of having prostate cancer (PCa) should be offered prostate-specific antigen (PSA) testing with risk-stratified follow-up. The Swedish National Board of Health and Welfare recommends against screening for PCa but supports regional implementation of organised prostate cancer testing (OPT). OBJECTIVE: To report the process for designing and implementing OPT programmes. DESIGN, SETTING, AND PARTICIPANTS: Population-based OPT programmes in two Swedish regions, designed to include men aged between 50 and 74 yr, launched in September 2020 for 50-yr-old men. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The number of men invited, the participation rate, and the numbers of magnetic resonance imaging (MRI) scans, urological visits, and biopsies from September 2020 to June 2021 were recorded. RESULTS AND LIMITATIONS: Two Swedish regions co-designed an OPT programme with a risk-stratified diagnostic algorithm based on prostate-specific antigen (PSA), PSA density, MRI findings, and age. An automated administrative system was developed on a nationwide web-based platform. Invitation letters and test results are automatically generated and sent out by post. Men with PSA ≥3ng/ml, a suspicious MRI lesion, and/or PSA density ≥0.15 ng/ml/cm3 are referred for a prostate biopsy. Test results are registered for quality control and research. By June 2021, a total of 16 515 men were invited, of whom 6309 (38%) participated; 147 had an MRI scan and 39 underwent prostate biopsy. The OPT framework, algorithm, and diagnostic pathways have been working well. CONCLUSIONS: We designed and implemented a framework for OPT with a high grade of automation. The framework and organisational experiences may be of value for others who plan a programme for early detection of PCa. PATIENT SUMMARY: We describe the implementation of an organised testing programme for early detection of prostate cancer in two Swedish regions. This model is the first of its kind and may serve as a template for similar programmes.

Fatigue in Patients With Head and Neck Cancer Treated With Radiation Therapy: A Prospective Study of Patient-Reported Outcomes and Their Association With Radiation Dose to the Cerebellum.

Purpose: Although fatigue is a known side effect in patients with head and neck cancer (HNC) receiving radiation therapy, knowledge regarding long-term fatigue and dose-response relationships to organs at risk is scarce. The aim of this prospective study was to analyze patient-reported fatigue in patients with HNC receiving radiation therapy and to explore any possible association with organ-at-risk doses. Methods and Materials: Patients with HNC referred for curative radiation therapy were eligible for inclusion in the study. To assess patient-reported fatigue, quality of life questionnaires (European Organization for Research and Treatment of Cancer QLQ-C30 and QLQ-FA12) were distributed before treatment and 1, 3, 6, 12, 24, and 60 months after the start of treatment. Mean dose (Dmean) and near maximum dose (D2%) of the cerebellum and brain stem were evaluated in relation to baseline-adjusted fatigue scores at 3 months. Results: One hundred twenty-six patients treated with intensity modulated radiation therapy between 2008 and 2010 were available for final analysis. Female sex and age <60 years were associated with higher fatigue at baseline, whereas patients also treated with chemotherapy had reduced physical and emotional fatigue at 6 months. Physical fatigue (QLQ-FA12 scale) increased from baseline up to 3 months (29 vs 59; P < .0001) but showed no difference compared with baseline from 1 to 5 years. Emotional fatigue was significantly lower at 5 years compared with baseline (14 vs 28; P < .0001). Patients with cerebellum Dmean > 3.5 Gy had higher mean physical fatigue scores at 3 months (38 vs 27; P = .036). Conclusions: Although there is a significant increase in fatigue scores for patients with HNC up to 1 year after radiation therapy, this study showed a return to baseline levels at 5 years. A possible association was found between physical fatigue and a higher mean dose to the cerebellum.

Neuropsychological functioning in childhood cancer survivors following cranial radiotherapy - results from a long-term follow-up clinic.

Treatment of malignant childhood posterior fossa tumors (CPFT) often includes surgical resection and craniospinal radiotherapy (CSI). Nasopharyngeal tumors in childhood (CNPHT) are often treated with surgery and radiotherapy (RT), leading to incidental brain irradiation. RT to the developing brain is associated with risks for cognitive impairments. We studied cognitive functioning, health-related quality of life (HRQOL), fatigue, and psychological distress, in adult survivors of CPFT and CNPHT, representing two groups, which had received high and low radiation dose-exposure to the brain, respectively. Cognitive tests were used to compare CPFT (n = 12) and CNPHT (n = 7) survivors to matched healthy controls (n = 28). HRQOL data was compared to the general population (GP) (n = 1415-1459). Average follow-up was 23 (CPFT) and 19 years (CNPHT). CPFT survivors had significant deficits in all cognitive domains. CNPHT survivors showed results below the control group but differed statistically only on one executive test. HRQOL-ratings indicated that both groups had similar self-reported cognitive problems. CPFT survivors reported more emotional problems and fatigue. Anxiety was seen in both CPFT and CNPHT survivors. This study confirmed long-term cognitive sequelae after RT in adult survivors of CPFT,and possible RT-induced cognitive deficits in adult CNPHT survivors.

Insights Gained From a Re-analysis of Five Improvement Cases in Healthcare Integrating System Dynamics Into Action Research.

BACKGROUND: Healthcare is complex with multi-professional staff and a variety of patient care pathways. Time pressure and minimal margins for errors, as well as tension between hierarchical power and the power of the professions, make it challenging to implement new policies or procedures. This paper explores five improvement cases in healthcare integrating system dynamics (SD) into action research (AR), aiming to identify methodological aspects of how this integration supported multi-professional groups to discover workable solutions to work-related challenges. METHODS: This re-analysis was conducted by a multi-disciplinary research group using an iterative abductive approach applying qualitative analysis to structure and understand the empirical material. Frameworks for consultancy assignments/client projects were used to identify case project stages (workflow steps) and socio-analytical questions were used to bridge between the AR and SD perspectives. RESULTS: All studied cases began with an extensive AR-inspired inventory of problems/objectives and ended with an SD-facilitated experimental phase where mutually agreed solutions were tested in silico. Time was primarily divided between facilitated group discussions during meetings and modelling work between meetings. Work principles ensured that the voice of each participant was heard, inspired engagement, interaction, and exploratory mutual learning activities. There was an overall pattern of two major divergent and convergent phases, as each group moved towards a mutually developed point of reference for their problem/objective and solution, a case-specific multi-professional knowledge repository. CONCLUSION: By integrating SD into AR, more favourable outcomes for the client organization may be achieved than when applying either approach in isolation. We found that SD provided a platform that facilitated experiential learning in the AR process. The identified results were calibrated to local needs and circumstances, and compared to traditional top-down implementation for change processes, improved the likelihood of sustained actualisation.

Effectiveness of tobacco cessation interventions for different groups of tobacco users in Sweden: a study protocol for a national prospective cohort study.

INTRODUCTION: Tobacco is still one of the single most important risk factors among the lifestyle habits that cause morbidity and mortality in humans. Furthermore, tobacco has a heavy social gradient, as the consequences are even worse among disadvantaged and vulnerable groups. To reduce tobacco-related inequity in health, those most in need should be offered the most effective tobacco cessation intervention. The aim of this study is to facilitate and improve the evaluation of already implemented national tobacco cessation efforts, focusing on 10 disadvantaged and vulnerable groups of tobacco users. METHODS AND ANALYSIS: This is a prospective cohort study. Data will be collected by established tobacco cessation counsellors in Sweden. The study includes adult tobacco or e-cigarette users, including disadvantaged and vulnerable patients, receiving in-person interventions for tobacco or e-cigarette cessation (smoking, snus and/or e-cigarettes). Patient inclusion was initiated in April 2020. For data analyses patients will be sorted into vulnerable groups based on risk factors and compared with tobacco users without the risk factor in question.The primary outcome is continuous successful quitting after 6 months, measured by self-reporting. Secondary outcomes include abstinence at the end of the treatment programme, which could be from minutes over days to weeks, 14-day point prevalence after 6 months, and patient satisfaction with the intervention. Effectiveness of successful quitting will be examined by comparing vulnerable with non-vulnerable patients using a mixed-effect logistic regression model adjusting for potential prognostic factors and known confounders. ETHICS AND DISSEMINATION: The project will follow the guidelines from the Swedish Data Protection Authority and have been approved by the Swedish Ethical Review Authority before patient inclusion (Dnr: 2019-02221). Only patients providing written informed consent will be included. Both positive and negative results will be published in scientific peer-reviewed journals and presented at national and international conferences. Information will be provided through media available to the public, politicians, healthcare providers and planners as these are all important stakeholders. TRIAL REGISTRATION NUMBER: NCT04819152.

Patients' experiences of well-being when being cared for in the intensive care unit-An integrative review.

OBJECTIVE: The aim of this integrative review was to identify facilitators and barriers to patients' well-being when being cared for in an ICU setting, from the perspective of the patients. BACKGROUND: To become critically ill and hospitalised in an ICU is a stressful, chaotic event due to the life-threatening condition itself, as well as therapeutic treatments and the environment. A growing body of evidence has revealed that patients often suffer from physical, psychological and cognitive problems after an ICU stay. Several strategies, such as sedation and pain management, are used to reduce stress and increase well-being during ICU hospitalisation, but the ICU experience nevertheless affects the body and mind. DESIGN; METHODS: Since research exploring patients' sense of well-being in an ICU setting is limited, an integrative review approach was selected. Searches were performed in CINAHL, Medline, Psych Info, Eric and EMBASE. After reviewing 66 studies, 12 studies were included in the integrative review. Thematic analysis was used to analyse the studies. The PRISMA checklist for systematic reviews was used. RESULTS: The results are presented under one main theme, 'Well-being as a multidimensional experience-interwoven in barriers and facilitators' and six sub-themes representing barriers to and facilitators of well-being in an ICU. Barriers identified were physical stressors, emotional stressors, environmental disturbances and insecurity relating to time and space. Facilitators were meeting physical needs and activities that included dimensions of a caring and relational environment. CONCLUSION: Our main findings were that experiences of well-being were multidimensional and included physical, emotional, relational and environmental aspects, and they were more often described through barriers than facilitators of well-being. RELEVANCE FOR CLINICAL PRACTICE: This integrative review has shown that it is necessary to adopt an individual focus on patient well-being in an ICU setting since physical, emotional, relational and environmental stressors might impact each patient differently.

Linear accelerator utilization: Concept and tool to aid the scheduling of patients for radiotherapy.

BACKGROUND AND PURPOSE: Resources in radiotherapy (RT) need to be used effectively to meet the current clinical demand. The aim of this data-driven study is to identify temporal trends in the scheduling of patients for RT and to develop a tool for a visual overview of future scheduling levels. MATERIAL AND METHODS: Scheduling data at an eight-linac modern RT department in Sweden were collected twice daily for planned and observed linac use in 2018-2020. Information was retrieved each day for the present (Day 0) and the forthcoming 100 weekdays with total linac utilization rates (LURs) calculated for two activity categories: treatment and non-treatment. An in-house tool based on the LUR concept, database queries from the oncology information system (OIS)/automatic calculations was developed and evaluated by RT managers and scheduling staff (n = 10). RESULTS: Overall median LURs were 87%/89% (planned/observed; p < 0.01) with more frequent and larger daily increase for non-treatment activities compared with treatment activities. LUR increased with shorter planning horizons and reached 100% for fully-operating linacs ≈3 weeks before Day 0. The tool was reported by 88% to ease the work and to contribute towards an even scheduling of patients (responses: 8/10). CONCLUSION: Alterations from a planned RT schedule occurs frequently. Having a tool that helps to reduce the abundance of booking information into clinically relevant overviews promise to increase the understanding of present and future scheduling levels. Our proposed concept and tool suggest that this is a feasible approach to schedule patients for RT more evenly.

Resource planning principles for the radiotherapy process using simulations applied to a longer vacation period use case.

PURPOSE: Radiotherapy (RT) resources need to be used wisely to balance workload and patient throughput. There are no known strategies on how to plan resource use around longer vacation periods to avoid patient waiting times. We created a simulation model over the RT workflow to evaluate different scenarios for this purpose. MATERIALS AND METHODS: The simulation model mimics a large modern RT department in Sweden. It was based on real data on patient referral patterns and resource use extracted from clinical systems (3666 treatment courses). Workshops with managers and staff were held to investigate nine different scenarios for the summer vacation period including one scenario to validate the model. Different capacity reductions, vacation period lengths and timing of the vacation periods between the preparatory part of the RT workflow and the treatment part were evaluated. RESULTS: For an eight-week period, resource utilization was predicted to be high both before and after the vacation period regardless of timing. However, more patients would be waiting with completed preparations with simultaneous vacation periods than when the preparatory part started one-two weeks prior to the treatment part. With shorter vacation periods, treatment would require overtime during the vacation period with higher levels of patients waiting compared to an eight-week scenario. CONCLUSIONS: Our proposed strategy aided managers to identify a preferred scenario for the summer vacation period with the preparatory part starting one-two weeks prior to the treatment part for an eight-week vacation period. This can help other RT departments to plan for similar situations.

Exploring the meaning, role and experiences of a patient-led social innovation for people affected by cancer: a new collaborative care model complementing traditional cancer rehabilitation in Sweden.

OBJECTIVE: Kraftens Hus is the first support centre in Sweden designed by and for people affected by cancer, including patients, family, friends, staff members and local community representatives (collectively 'stakeholders'). The purpose of this study was to explore the meaning, role and experiences of Kraftens Hus stakeholders using a patient and public involved methodology. METHODS: To understand and map the experiences of visitors to Kraftens Hus, we applied concept mapping (CM), a mixed methods approach where data are collected and analysed in four structured steps designed to capture the diverse perspectives of multiple stakeholders. Qualitative interviews with relevant stakeholders supplemented the CM findings. RESULTS: The final concept map contained six clusters of ideas. Within the clusters, there was a recurring theme that cancer-affected people value accessible and long-term psychosocial support (PSS). The intended emotional, social and practical needs identified in a previous design process seem to have been addressed and appreciated by Kraftens Hus visitors. CONCLUSION: Kraftens Hus is an example of a new patient-led social innovation based on a life-event perspective and integration of resources from different sectors in society. By focusing on life, not the disease, the care continuum expands, and long-term PSS is provided alongside cancer treatment. The evaluation confirms that PSS should focus on health and well-being in the broadest sense.

Low Spatial Peak-to-Average Power Ratio Transmission for Improved Energy Efficiency in Massive MIMO Systems.

A significant portion of the operating power of a base station is consumed by power amplifiers (PAs). Much of this power is dissipated in the form of heat, as the overall efficiency of currently deployed PAs is typically very low. This is because the structure of conventional precoding techniques typically results in a relatively high variation in output power at different antennas in the array, and many PAs are operated well below saturation to avoid distortion of the transmitted signals. In this work, we use a realistic model for power consumption in PAs and study the impact of power variation across antennas in the array on the energy efficiency of a massive MIMO downlink system. We introduce a family of linear precoding matrices that allow us to control the spatial peak-to-average power ratio by projecting a fraction of the transmitted power onto the null space of the channel. These precoding matrices preserve the structure of conventional precoders; e.g., they suppress multiuser interference when used together with zeroforcing precoding and bring advantages over these precoders by operating PAs in a more power-efficient region and reducing the total radiated distortion. Our numerical results show that by controlling the power variations between antennas in the array and incorporating the nonlinearity properties of PA into the precoder optimization, significant gains in energy efficiency can be achieved over conventional precoding techniques.

An analytical approach to aggregate patient inflows to a simulation model over the radiotherapy process.

BACKGROUND: In meeting input data requirements for a system dynamics (SD) model simulating the radiotherapy (RT) process, the number of patient care pathways (RT workflows) needs to be kept low to simplify the model without affecting the overall performance. A large RT department can have more than 100 workflows, which results in a complex model structure if each is to be handled separately. Here we investigated effects on model performance by reducing the number of workflows for a model of the preparatory steps of the RT process. METHODS: We created a SD model sub-structure capturing the preparatory RT process. Real data for patients treated in 2015-2016 at a modern RT department in Sweden were used. RT workflow similarity was quantified by averaged pairwise utilization rate differences (%) and the size of corresponding correlation coefficients (r). Grouping of RT workflows was determined using two accepted strategies (80/20 Pareto rule; merging all data into one group) and a customized algorithm with r≥0.75:0.05:0.95 as criteria for group inclusion by two strategies (A1 and A2). Number of waiting patients for each grouping strategy were compared to the reference of all workflows handled separately. RESULTS: There were 128 RT workflows for 3209 patients during the studied period. The 80/20 Pareto rule resulted in 14/8/21 groups for curative/palliative/disregarding treatment intent. Correspondingly, A1 and A2 resulted in 7-40/≤4-36/7-82 groups depending on r cutoff. Results for the Pareto rule and A2 at r≥85 were comparable to the reference. CONCLUSIONS: The performance of a simulation model over the RT process will depend on the grouping strategy of patient input data. Either the Pareto rule or the grouping of patients by resource use can be expected to better reflect overall departmental effects to various changes than when merging all data into one group. Our proposed approach to identify groups based on similarity in resource use can potentially be used in any setting with variable incoming flows of objects which go through a multi-step process comparable to RT where the aim is to reduce the complexity of associated model structures without compromising with overall performance.

Health-related quality of life in patients with primary brain tumors during and three months after treatment with proton beam therapy.

BACKGROUND: Proton beam therapy (PBT) is increasingly administered to patients with primary brain tumors. Benefits of new treatments must be weighed against side effects and possible deterioration in health-related quality of life (HRQoL). The aim of this study was to describe and compare HRQoL, including acute symptom experiences and associated factors, in patients with malignant and benign brain tumors treated with PBT. MATERIALS AND METHODS: Adult PBT-treated patients with primary brain tumors (n = 266) were studied. HRQoL was assessed with EORTC QLQ-C30, QLQ-BN20, HADS, ISI and MFI before, during and three months after treatment. Associations with demographic and medical factors were explored. RESULTS: Between baseline and three months post-treatment: HRQoL decreased significantly in the global health/QOL domains physical functioning, role functioning and cognitive functioning in the malignant group, global health/QOL and physical functioning decreased significantly in the benign group, more comorbidity was significantly associated with increased motor dysfunction, leg weakness, headache and future uncertainty. Fatigue and depression were the most frequent symptoms in both groups. Independent predictors of risk factor recognition were age, sex, chemotherapy, comorbidity and education level. DISCUSSION: Global health/QOL in patient with brain tumors is very complex and multidimensional. Symptoms are interrelated and related to patient, tumor and treatment factors. It is important to identify aspects of HRQoL that may be affected by treatment. These include both benefits, expected to improve HRQoL, and negative changes such as symptom experience and influencing factors. Evidence-based guidelines are needed for symptom management, and for high quality of care for patients experiencing low PBT-related HRQoL.