| 1. |
- Boström, Martina, et al.
(author)
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A role for endothelial cells in radiation-induced inflammation
- 2018
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In: International Journal of Radiation Biology. - : Informa UK Limited. - 0955-3002 .- 1362-3095. ; 94:3, s. 259-271
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Journal article (peer-reviewed)abstract
- Purpose: To unravel the role of the vasculature in radiation-induced brain tissue damage.Materials and methods: Postnatal day 14 mice received a single dose of 10Gy cranial irradiation and were sacrificed 6h, 24h or 7 days post-irradiation. Endothelial cells were isolated from the hippocampus and cerebellum using fluorescence-activated cell sorting, followed by cell cycle analysis and gene expression profiling.Results: Flow cytometric analysis revealed that irradiation increased the percentage of endothelial cells, relative to the whole cell population in both the hippocampus and the cerebellum. This change in cell distribution indicates that other cell types are more susceptible to irradiation-induced cell death, compared to endothelial cells. This was supported by data showing that genes involved in endothelial cell-specific apoptosis (e.g. Smpd1) were not induced at any time point investigated but that genes involved in cell-cycle arrest (e.g. Cdkn1a) were upregulated at all investigated time points, indicating endothelial cell repair. Inflammation-related genes, on the other hand, were strongly induced, such as Ccl2, Ccl11 and Il6.Conclusions: We conclude that endothelial cells are relatively resistant to ionizing radiation but that they play an active, hitherto unknown, role in the inflammatory response after irradiation. In the current study, this was shown in both the hippocampus, where neurogenesis and extensive cell death after irradiation occurs, and in the cerebellum, where neurogenesis no longer occurs at this developmental age.
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| 2. |
- Boström, Martina, et al.
(author)
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Chronic disturbance in the thalamus following cranial irradiation to the developing mouse brain
- 2019
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In: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9:1
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Journal article (peer-reviewed)abstract
- Better survival rates among pediatric brain tumor patients have resulted in an increased awareness of late side effects that commonly appear following cancer treatment. Radiation-induced changes in hippocampus and white matter are well described, but do not explain the full range of neurological late effects in childhood cancer survivors. The aim of this study was to investigate thalamus following cranial irradiation (CIR) to the developing brain. At postnatal day 14, male mice pups received a single dose of 8Gy CIR. Cellular effects in thalamus were assessed using immunohistochemistry 4 months after CIR. Interestingly, the density of neurons decreased with 35% (p=0.0431) and the density of astrocytes increased with 44% (p=0.011). To investigate thalamic astrocytes, S100β+ cells were isolated by fluorescence-activated cell sorting and genetically profiled using next-generation sequencing. The phenotypical characterization indicated a disrupted function, such as downregulated microtubules' function, higher metabolic activity, immature phenotype and degraded ECM. The current study provides novel insight into that thalamus, just like hippocampus and white matter, is severely affected by CIR. This knowledge is of importance to understand the late effects seen in pediatric brain tumor survivors and can be used to give them the best suitable care.
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| 3. |
- Bull, Cecilia, 1977, et al.
(author)
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A novel mouse model of radiation-induced cancer survivorship diseases of the gut
- 2017
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In: American journal of physiology. Gastrointestinal and liver physiology. - : American Physiological Society. - 1522-1547 .- 0193-1857. ; 313:5, s. G456-G466
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Journal article (peer-reviewed)abstract
- A deeper understanding of the radiation-induced pathophysiological processes that develop in the gut is imperative to prevent, alleviate, or eliminate cancer survivorship diseases after radiotherapy to the pelvic area. Most rodent models of high-dose gastrointestinal radiation injury are limited by high mortality. We therefore established a model that allows for the delivering of radiation in fractions at high doses while maintaining long-term survival. Adult male C57/BL6 mice were exposed to small-field irradiation, restricted to 1.5 cm of the colorectum using a linear accelerator. Each mouse received 6 or 8 Gy, two times daily in 12-h intervals in two, three, or four fractions. Acute cell death was examined at 4.5 h postirradiation and histological changes at 6 wk postirradiation. Another group was given four fractions of 8 Gy and followed over time for development of visible symptoms. Irradiation caused immediate cell death, mainly limited to the colorectum. At 6 wk postirradiation, several crypts displayed signs of radiation-induced degeneration. The degenerating crypts were seen alongside crypts that appeared perfectly healthy. Crypt survival was reduced after the fourth fraction regardless of dose, whereas the number of macrophages increased. Angiogenesis was induced, likely as a compensatory mechanism for hypoxia. Four months postirradiation, mice began to show radiation-induced symptoms, and histological examination revealed an extensive crypt loss and fibrosis. Our model is uniquely suitable for studying the long-term trajectory and underlying mechanisms of radiation-induced gastrointestinal injury. NEW & NOTEWORTHY A novel mouse model for studying the long-term trajectory of radiation-induced gut injury. The method allows for the use of high doses and multiple fractions, with minor impact on animal health for at least 3 mo. Crypt loss and a slow progression of fibrosis is observed. Crypt degeneration is a process restricted to isolated crypts. Crypt degeneration is presented as a convenient proxy endpoint for long-term radiation-induced gut injury.
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| 4. |
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| 5. |
- Kalm, Marie, 1981, et al.
(author)
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Serum concentrations of the axonal injury marker neurofilament light protein are not influenced by blood-brain barrier permeability
- 2017
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In: Brain Research. - : Elsevier BV. - 0006-8993. ; 1668, s. 12-19
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Journal article (peer-reviewed)abstract
- A blood biomarker to monitor individual susceptibility to neuronal injury from cranial radiotherapy could potentially help to individualize radiation treatment and thereby reduce the incidence and severity of late effects. An important feature of such a blood biomarker is that its concentration is not confounded by varying degrees of release from the brain into the blood across the blood-brain barrier (BBB). In this study, we investigated serum neurofilament light protein (NFL) concentrations in 21-day old mice following a single dose of cranial irradiation (8 Gy). Cranial irradiation resulted in acute cell injury measured as a 12.9-fold increase in caspase activity 6 h after irradiation; activation of inflammation measured by levels of CCL2 and increased BBB permeability measured by C-14-sucrose concentration ratios in brain and cerebrospinal fluid (CSF). Serum levels of NFL peaked at 6 h after both anesthesia and cranial irradiation, but no timely correlation of serum NFL concentration with BBB permeability was found. Further, three groups of patients with different degrees of BBB impairment (measured as the CSF/serum albumin ratio) were investigated. There was no correlation between serum NFL concentration and CSF/serum albumin ratio (r = 0.139, p = 0.3513), however a strong correlation was found for NFL concentration in serum and NFL concentration in CSF (r = 0.6303, p < 0.0001). In conclusion, serum NFL appears to be a reliable blood biomarker for neuronal injury, and its concentration is not confounded by BBB permeability. (C) 2017 Elsevier B.V. All rights reserved.
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| 6. |
- Abel, Edvard, 1970, et al.
(author)
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Impact on quality of life of IMRT versus 3-D conformal radiation therapy in head and neck cancer patients: A case control study
- 2017
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In: Advances in Radiation Oncology. - : Elsevier BV. - 2452-1094. ; 2:3, s. 346-353
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Journal article (peer-reviewed)abstract
- Objective The purpose of this study was to prospectively and longitudinally compare the health-related quality of life (HRQOL) outcomes between head and neck (HN) cancer patients treated with parotid-sparing intensity modulated radiation therapy (IMRT) and patients treated with 3-dimensional conventional radiation therapy (3D-CRT). Methods and materials Before and up to 12 months after treatment, HRQOL was recorded in patients with HN cancer who were referred to the Department of Oncology at Sahlgrenska University Hospital for curative IMRT. The study group's HRQOL was compared with a matched group of patients from previous descriptive HRQOL studies treated with 3D-CRT. Both groups' HRQOL was measured by the European Organization for Research and Treatment for Cancer QLQ-C30 and European Organization for Research and Treatment for Cancer QLQ-HN35 at 6 time points in the first year after diagnosis. Results Two hundred and seven patients were included, 111 treated with IMRT and 96 matched controls treated with 3D-CRT. Both groups' HRQOL deteriorated during and after treatment. Just after treatment, worse HRQOL scores were observed in the IMRT group regarding insomnia (38 vs 27; P = .032), appetite loss (64 vs 50; P = .019), senses (54 vs 41; P = .017), and coughing (39 vs 26, P = .009). At 12 months, however, significantly better HRQOL scores were observed in the IMRT group regarding problems with dry mouth (72 vs 62; P = .018), pain (28 vs 20; P = .018), sexuality (37 vs 23; P = .016), social contacts (10 vs 6; P = .026), cognitive functioning (79 vs 87; P = .0057), and financial difficulties (12 vs 20; P = .0019). Conclusions This study further supports the hypothesis that the introduction of IMRT has improved the long-term quality of life of HN cancer patients who have been treated with radiation therapy, but might cause more acute side effects. Longer follow-up is needed to study late complications.
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| 7. |
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| 8. |
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| 9. |
- Fernström, Erik, et al.
(author)
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Results of preoperative chemoradiotherapy for patients with advanced cancer of the nasal cavity and paranasal sinuses.
- 2017
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In: Acta oto-laryngologica. - : Informa UK Limited. - 1651-2251 .- 0001-6489. ; 137:12, s. 1292-1300
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Journal article (peer-reviewed)abstract
- Curative treatment of nasal cavity and paranasal sinus cancer is challenging due to the proximity to critical anatomical structures. The purpose of this study was to analyze the impact of trimodality therapy with preoperative chemotherapy and reduced-dose radiotherapy followed by organ-preserving surgery for treating patients with nasal cavity and paranasal sinus cancer.This retrospective study included all 156 patients diagnosed with sinonasal cancer in western Sweden between 1986 and 2009. We determined the treatment selection pattern and treatment outcomes for 79 patients treated with preoperative chemoradiotherapy.Squamous cell carcinoma was the most common histology. The five-year overall survival was 54%, and 85% of these patients had T3 or T4 tumors. The five-year cumulative incidence rate of local recurrence was 32%. The five-year overall survival in patients with squamous cell carcinoma and adenocarcinoma was 45% and 76%, respectively. The median preoperative radiation dose was 48Gy. Orbital exenteration was performed in 7% of patients.Preoperative chemoradiotherapy may be beneficial for patients with advanced sinonasal cancer when primary radical surgery is challenging. Survival outcomes were comparable to outcomes reported in the literature despite conservative surgery and relatively low radiation doses in patients with locally advanced tumors.
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| 10. |
- Flejmer, Anna M.
(author)
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Radiation burden from modern radiation therapy techniques including proton therapy for breast cancer treatment - clinical implications
- 2016
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Doctoral thesis (other academic/artistic)abstract
- The purpose of this thesis was to study the clinical implications of modern radiotherapy techniques for breast cancer treatment. This was investigated in several individual studies.Study I investigated the implications of using the analytical anisotropic algorithm (AAA) from the perspective of clinical recommendations for breast cancer radiotherapy. Pencil beam convolution plans of 40 breast cancer patients were recalculated with AAA. The latter plans had a significantly worse coverage of the planning target volume (PTV) with the 93% isodose, higher maximum dose in hotspots, higher volumes of the ipsilateral lung receiving doses below 25 Gy and smaller volumes with doses above 25 Gy. AAA also predicted lower doses to the heart.Study II investigated the implications of using the irregular surface compensator (ISC), an electronic compensation algorithm, in comparison to three‐dimensional conformal radiotherapy (3D‐CRT) for breast cancer treatment. Ten breast cancer patients were planned with both techniques. The ISC technique led to better coverage of the clinical target volume of the tumour bed (CTV‐T) and PTV in almost all patients with significant improvement in homogeneity.Study III investigated the feasibility of using scanning pencil beam proton therapy for regional and loco‐regional breast cancer with comparison of ISC photon planning. Ten patients were included in the study, all with dose heterogeneity in the target and/or hotspots in the normal tissues outside the PTV. The proton plans showed comparable or better CTV‐T and PTV coverage, with large reductions in the mean doses to the heart and the ipsilateral lung.Study IV investigated the added value of enhanced inspiration gating (EIG) for proton therapy. Twenty patients were planned on CT datasets acquired during EIG and freebreathing (FB) using photon 3D‐CRT and scanning proton therapy. Proton spot scanning has a high potential to reduce the irradiation of organs‐at‐risk for most patients, beyond what could be achieved with EIG and photon therapy, especially in terms of mean doses to the heart and the left anterior descending artery.Study V investigated the impact of physiological breathing motion during proton radiotherapy for breast cancer. Twelve thoracic patients were planned on CT datasets during breath‐hold at inhalation phase and breath‐hold at exhalation phase. Between inhalation and exhalation phase there were very small differences in dose delivered to the target and cardiovascular structures, with very small clinical implication.The results of these studies showed the potential of various radiotherapy techniques to improve the quality of life for breast cancer patients by limiting the dose burden for normal tissues.
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| 11. |
- Gasic, D., et al.
(author)
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Retrospective estimation of heart and lung doses in pediatric patients treated with spinal irradiation
- 2018
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In: Radiotherapy and Oncology. - : Elsevier BV. - 0167-8140. ; 128:2, s. 209-213
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Journal article (peer-reviewed)abstract
- Background and purpose: The purpose of this study was to investigate whether treatment information from medical records can be used to estimate radiation doses to heart and lungs retrospectively in pediatric patients receiving spinal irradiation with conventional posterior fields. Material and methods: An algorithm for retrospective dosimetry in children treated with spinal irradiation was developed in a cohort of 21 pediatric patients with available CT-scans and treatment plans. We developed a multivariable linear regression model with explanatory variables identifiable in case note review for retrospective estimation of minimum, maximum, mean and V-10%-V-80% doses to the heart and lungs. Doses were estimated for both linear accelerator (Linac) and Co-60 radiation therapy modalities. Results: Age and spinal field width were identified as statistically significant predictors of heart and lung doses in multivariable analyses (p < 0.01 in all models). Models showed excellent predictive performance with R-2 = 0.70 for mean heart dose and 0.79 for mean lung dose, for Linac plans. In leave-one-out cross-validation analysis the average difference between predicted and actual mean heart dose was 6.7% and 7.6% of the prescription dose for Linac and Co-60 plans, respectively, and 5.2% and 4.9% for mean lung dose. Due to the small sample size and large inter-patient variation in heart and lung dose, prospective studies validating these findings are highly warranted. Conclusions: The models presented here provide retrospective estimates of heart and lung doses for historical cohorts of pediatric patients, thus facilitating studies of long-term adverse effects of radiation. (C) 2018 Elsevier B.V. All rights reserved.
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| 12. |
- Kalm, Marie, 1981, et al.
(author)
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C3 deficiency ameliorates the negative effects of irradiation of the young brain on hippocampal development and learning.
- 2016
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In: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 7:15, s. 19382-94
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Journal article (peer-reviewed)abstract
- Radiotherapy in the treatment of pediatric brain tumors is often associated with debilitating late-appearing adverse effects, such as intellectual impairment. Areas in the brain harboring stem cells are particularly sensitive to irradiation (IR) and loss of these cells may contribute to cognitive deficits. It has been demonstrated that IR-induced inflammation negatively affects neural progenitor differentiation. In this study, we used mice lacking the third complement component (C3-/-) to investigate the role of complement in a mouse model of IR-induced injury to the granule cell layer (GCL) of the hippocampus. C3-/- and wild type (WT) mice received a single, moderate dose of 8 Gy to the brain on postnatal day 10. The C3-/- mice displayed 55 % more microglia (Iba-1+) and a trend towards increase in proliferating cells in the GCL compared to WT mice 7 days after IR. Importantly, months after IR C3-/- mice made fewer errors than WT mice in a reversal learning test indicating better learning capacity in C3-/- mice after IR. Notably, months after IR C3-/- and WT mice had similar GCL volumes, survival of newborn cells (BrdU), microglia (Iba-1) and astrocyte (S100β) numbers in the GCL. In summary, our data show that the complement system contributes to IR-induced loss of proliferating cells and maladaptive inflammatory responses in the acute phase after IR, leading to impaired learning capacity in adulthood. Targeting the complement system is hence promising for future strategies to reduce the long-term adverse consequences of IR in the young brain.
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| 13. |
- Langegård, Ulrica, 1969, et al.
(author)
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Evaluation of quality of care in relation to health-related quality of life of patients diagnosed with brain tumor : a novel clinic for proton beam therapy
- 2019
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In: Supportive Care in Cancer. - : Springer. - 0941-4355 .- 1433-7339. ; 27:7, s. 2679-2691
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Journal article (peer-reviewed)abstract
- Purpose: Patients with brain tumors constitute a vulnerable group, and it is important that they receive the highest quality of care (QoC). The study aim was to describe the perceptions of QoC and its association with health-related quality of life in brain tumor patients undergoing proton beam therapy in a newly established clinic.Method: Data were collected at the start of treatment and after 3 and 6weeks. Adult patients (18years old) with brain tumors (n=186) completed two self-administered questionnaires: a modified Quality from the Patients' Perspective, which measures perceived reality and subjective importance of care, and the EORTC QLQ-C30. Data were analyzed using parametric and non-parametric statistical tests.Results: The perceived QoC was highest for treatment information and lowest for dietician and smoking information, whereas interaction with doctors and nurses was rated as the most important aspect of quality of care. Subjective importance ratings were significantly higher than perceived reality ratings for 60% of items. A better global health was moderately correlated with a higher perceived support for fatigue.Conclusions: A need for quality improvement was identified for several aspects of patient care. Greater symptom distress during the treatment period led to greater perceived importance of symptom support. Ensuring QoC is complex and collaboration with other health care professionals is essential.Relevance to clinical practice: The clinic could improve QoC regarding information about possible symptoms, adjust care according to patient perceptions of importance, and involve patients in care decisions.
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| 14. |
- Langegård, Ulrica, 1969, et al.
(author)
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Symptom Clusters in Patients With Brain Tumors Undergoing Proton Beam Therapy
- 2019
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In: Oncology Nursing Forum. - : Oncology Nursing Society. - 0190-535X .- 1538-0688. ; 46:3, s. 349-363
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Journal article (peer-reviewed)abstract
- OBJECTIVES: To explore symptom clusters during proton beam therapy in patients with primary brain tumors and investigate associations among symptom clusters, demographic variables, and comorbidity in this patient population.SAMPLE & SETTING: Data were collected from 187 adult patients with primary brain tumors during their treatment periods in the Skandion Clinic in Uppsala, Sweden. Symptoms were assessed with the Radiotherapy-Related Symptoms Assessment Scale, and comorbidity was evaluated with the Self-Administered Comorbidity Questionnaire.METHODS & VARIABLES: The study used a quantitative and longitudinal design. Exploratory factor analysis was used to determine the underlying structure of symptom clusters.RESULTS: Three clusters were identified: mood, reduced appetite, and reduced energy. The mood cluster had the highest factor loadings (0.71-0.86). In addition, demographic and comorbidity characteristics were associated with symptom clusters in this group of patients.IMPLICATIONS FOR NURSING: Building knowledge about how these symptoms interact and are clustered will support healthcare professionals to more efficiently relieve symptom clusters during proton beam therapy.
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| 15. |
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| 16. |
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| 17. |
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| 18. |
- Mofors, J., et al.
(author)
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Concomitant Ro/SSA and La/SSB antibodies are biomarkers for the risk of venous thromboembolism and cerebral infarction in primary Sjögren's syndrome
- 2019
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In: Journal of Internal Medicine. - : John Wiley & Sons. - 0954-6820 .- 1365-2796. ; 286:4, s. 458-468
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Journal article (peer-reviewed)abstract
- Background: To assess the risk of incident cardiovascular disease in patients with primary Sjögren's syndrome, overall and stratified by Ro/SSA and La/SSB autoantibody status.Methods: A cohort of patients with primary Sjögren's syndrome in Sweden (n = 960) and matched controls from the general population (n = 9035) were included, and data extracted from the National Patient Register to identify events of myocardial infarction, cerebral infarction and venous thromboembolism. Hazard ratios were estimated using cox proportional hazard regressions.Results: During a median follow‐up of 9.5 years, the overall hazard ratio (HR) was 1.6 (95% CI 1.2–2.1) for myocardial infarction, 1.2 (95% CI 0.9–1.7) for cerebral infarction and 2.1 (95% CI 1.6–2.9) for venous thromboembolism. Patients positive for both Ro/SSA and La/SSB autoantibodies had a substantially higher risk of cerebral infarction (HR 1.7, 95% CI 1.0–2.9) and venous thromboembolism (HR 3.1, 95% CI 1.9–4.8) than the general population. These risks were not significantly increased in Ro/SSA‐ and La/SSB‐negative patients. Among autoantibody‐positive patients, the highest HR of cerebral infarction was seen after ≥10 years disease duration (HR 2.8, 95% CI 1.4–5.4), while the HR for venous thromboembolism was highest 0–5 years after disease diagnosis (HR 4.7, 95% CI 2.3–9.3) and remained high throughout disease duration.Conclusions: Primary Sjögren's syndrome is associated with a markedly increased risk of cardiovascular disease and the presence of Ro/SSA and La/SSB autoantibodies identify the subgroup of patients carrying the highest risk. These findings suggest that monitoring and prevention of cardiovascular disease in this patient group should be considered.
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| 19. |
- Mofors, J., et al.
(author)
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Infections increase the risk of developing Sjögren's syndrome
- 2019
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In: Journal of Internal Medicine. - : Wiley-Blackwell. - 0954-6820 .- 1365-2796. ; 285:6, s. 670-680
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Journal article (peer-reviewed)abstract
- Objective: Environmental factors have been suggested in the pathogenesis of rheumatic diseases. We here investigated whether infections increase the risk of developing primary Sjögren's syndrome (pSS).Methods: Patients with pSS in Sweden (n = 945) and matched controls from the general population (n = 9048) were included, and data extracted from the National Patient Register to identify infections occurring before pSS diagnosis during a mean observational time of 16.0 years. Data were analysed using conditional logistic regression models. Sensitivity analyses were performed by varying exposure definition and adjusting for previous health care consumption.Results: A history of infection associated with an increased risk of pSS (OR 1.9, 95% CI 1.6–2.3). Infections were more prominently associated with the development of SSA/SSB autoantibody‐positive pSS (OR 2.7, 95% CI 2.0–3.5). When stratifying the analysis by organ system infected, respiratory infections increased the risk of developing pSS, both in patients with (OR 2.9, 95% CI 1.8–4.7) and without autoantibodies (OR 2.1, 95% CI 1.1–3.8), whilst skin and urogenital infections only significantly associated with the development of autoantibody‐positive pSS (OR 3.2, 95% CI 1.8–5.5 and OR 2.7, 95% CI 1.7–4.2). Furthermore, a dose–response relationship was observed for infections and a risk to develop pSS with Ro/SSA and La/SSB antibodies. Gastrointestinal infections were not significantly associated with a risk of pSS.Conclusions: Infections increase the risk of developing pSS, most prominently SSA/SSB autoantibody‐positive disease, suggesting that microbial triggers of immunity may partake in the pathogenetic process of pSS.
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| 20. |
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| 21. |
- Pettersson, Erik, 1987, et al.
(author)
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Structure delineation in the presence of metal - A comparative phantom study using single and dual-energy computed tomography with and without metal artefact reduction
- 2019
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In: Physics and Imaging in Radiation Oncology. - : Elsevier BV. - 2405-6316. ; 9, s. 43-49
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Journal article (peer-reviewed)abstract
- Background and purpose: Metal artefacts in computed tomography (CT) images impairs structure delineation. These artefacts can potentially be reduced with dual-energy CT (DECT) with or without using metal artefact reduction (MAR). The purpose was to investigate how structure delineation in DECT with or without MAR and single-energy CT (SECT) images were affected by metals. Materials and methods: A phantom with known irregular structures was developed. References tructures were determined from a low-noise scan without metal. Bilateral hip prostheses were simulated with steel or titanium inserts. The phantom was scanned with SECT and fast-kV switching DECT with optional MAR. Four radiation oncologists delineated the structures in two phantom set-ups. Delineated structures were evaluated with Dice similarity coefficient (DSC) and Hausdorff distance relative to the reference structures. Results: With titanium inserts, more structures were detected for non-MAR DECT compared to SECT while the same or less were detected with steel inserts. MAR improved delineation in DECT images. For steel inserts, Three structures in the region of artefacts, were delineated by at least two oncologists with MAR-DECT compared to none with non-MAR DECT or SECT. The highest values of DSC for MAR-DECT were 0.69, 0.81 and 0.77 for those structures. Conclusions: Delineation was improved with non-MAR DECT compared to SECT, especially for titanium inserts. A larger improvement was seen with the use of MAR for both steel and titanium inserts. The improvement was dependent on the location of the structure relative to the inserts, and the structure contrast relative to the background.
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| 22. |
- Sabel, Magnus, 1966, et al.
(author)
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Hypothermia after cranial irradiation protects neural progenitor cells in the subventricular zone but not in the hippocampus.
- 2017
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In: International journal of radiation biology. - : Informa UK Limited. - 1362-3095 .- 0955-3002. ; 93:8, s. 771-783
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Journal article (peer-reviewed)abstract
- To explore if hypothermia can reduce the harmful effects of ionizing radiation on the neurogenic regions of the brain in young rats.Postnatal day 9 rats were randomized into two treatment groups, hypo- and normothermia, or a control group. Treatment groups were placed in chambers submerged in temperature-controlled water baths (30˚C and 36˚C) for 8h, after receiving a single fraction of 8Gy to the left hemisphere. Seven days post-irradiation, we measured the sizes of the subventricular zone (SVZ) and the granule cell layer (GCL) of the hippocampus, and counted the number of proliferating (phospho-histone H3+) cells and microglia (Iba1+ cells).Irradiation caused a 53% reduction in SVZ size in the normothermia group compared to controls, as well as a reduction of proliferating cell numbers by >50%. These effects were abrogated in the hypothermia group. Irradiation reduced the number of microglia in both treatment groups, but resulted in a lower cell density of Iba1+ cells in the SVZs of the hypothermia group. In the GCL, irradiation decreased both GCL size and the proliferating cell numbers, but with no difference between the treatment groups. The number of microglia in the GCL did not change.Hypothermia immediately after irradiation protects the SVZ and its proliferative cell population but the GCL is not protected, one week post-irradiation.
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| 23. |
- Smith, Frida, 1973, et al.
(author)
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Evaluating the implementation and use of the regional cancer plan in Western Sweden through concept mapping
- 2019
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In: International Journal for Quality in Health Care. - : Oxford University Press (OUP). - 1464-3677 .- 1353-4505. ; 31:7, s. G44-G52
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Journal article (peer-reviewed)abstract
- Quality problem or issue: Within healthcare, policy documents are often used to strategically standardize, streamline or change how general health issues are managed for a specific patient group or treatment. Despite significant effort in developing policy and strategic planning documents, these may not have the intended impact and their value has long been questioned by practitioners. Choice of solution: To identify barriers and affordances for the implementation and use of a strategic plan for cancer care in the Western Sweden Healthcare Region, we used Concept Mapping; a participatory mixed method approach to inquiry consisting of both qualitative and quantitative tasks intended to elicit and integrate the diverse perspectives of multiple stakeholders. Implementation: The study was carried out between April and October 2017 and consisted of several sequential data collection steps: idea generation, sorting and rating ideas for importance and feasibility. Stakeholders from different levels and professions in cancercare participated, but the number varied in the separate steps of data collection: idea generation (n = 112), sorting (n = 16) and rating (n = 38). Evaluation: A concept map visualized seven areas that stakeholders throughout the cancer-care process considered necessary to address in order to enable the implementation of the plan. Skills provision was considered the most important cluster but also rated as least feasible. A consistent theme emerged that information, or lack thereof, might be a barrier for the plan being put into action to a greater extent in the cancer-care units. Nine actionable ideas rated highly on both importance and feasibility were presented as a go-zone. Lessons learned: Our results suggest that efforts might be better spent on ensuring information about and accessibility to strategic documents throughout the organization, rather than frequently updating them or producing new ones. Having sufficient skills provision seems to be the prerequisite for successful implementation.
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| 24. |
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| 25. |
- Stock, M., et al.
(author)
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Harmonization of proton treatment planning for head and neck cancer using pencil beam scanning: first report of the IPACS collaboration group
- 2019
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In: Acta Oncologica. - : Informa UK Limited. - 0284-186X .- 1651-226X. ; 58:12, s. 1720-1730
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Journal article (peer-reviewed)abstract
- Background and purpose: A collaborative network between proton therapy (PT) centres in Trento in Italy, Poland, Austria, Czech Republic and Sweden (IPACS) was founded to implement trials and harmonize PT. This is the first report of IPACS with the aim to show the level of harmonization that can be achieved for proton therapy planning of head and neck (sino-nasal) cancer. Methods: CT-data sets of five patients were included. During several face-to-face and online meetings, a common treatment planning protocol was developed. Each centre used its own treatment planning system (TPS) and planning approach with some restrictions specified in the treatment planning protocol. In addition, volumetric modulated arc therapy (VMAT) photon plans were created. Results: For CTV1, the average D-median was 59.3 +/- 2.4 Gy(RBE) for protons and 58.8 +/- 2.0 Gy(RBE) for VMAT (aim was 56 Gy(RBE)). For CTV2, the average D-median was 71.2 +/- 1.0 Gy(RBE) for protons and 70.6 +/- 0.4 Gy(RBE) for VMAT (aim was 70 Gy(RBE)). The average D-2% for the spinal cord was 25.1 +/- 8.5 Gy(RBE) for protons and 47.6 +/- 1.4 Gy(RBE) for VMAT. The average D-2% for chiasm was 46.5 +/- 4.4 Gy(RBE) for protons and 50.8 +/- 1.4 Gy(RBE) for VMAT, respectively. Robust evaluation was performed and showed the least robust plans for plans with a low number of beams. Discussion: In conclusion, several influences on harmonization were identified: adherence/interpretation to/of the protocol, available technology, experience in treatment planning and use of different beam arrangements. In future, all OARs that should be included in the optimization need to be specified in order to further harmonize treatment planning.
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| 26. |
- Zackrisson, Björn, et al.
(author)
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Mature results from a Swedish comparison study of conventional versus accelerated radiotherapy in head and neck squamous cell carcinoma - The ARTSCAN trial
- 2015
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In: Radiotherapy and Oncology. - : Elsevier BV. - 0167-8140 .- 1879-0887. ; 117:1, s. 99-105
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Journal article (peer-reviewed)abstract
- Background and purpose: This report contains the mature five-year data from the Swedish ARTSCAN trial including information on the influence of p16 positivity (p16+) for oropharyngeal cancers. Material and methods: Patients with previously untreated squamous cell carcinoma without distant metastases of the oral cavity, oropharynx, larynx (except T1-2, NO glottic cancers) and hypopharynx were included. Patients were randomised between accelerated fractionation (AF) (1.1 Gy + 2 Gy per day, 5 days/week for 4.5 weeks, total dose 68 Gy) and conventional fractionation (CF) (2 Gy per day, 5 days/week for 7 weeks, total dose 68 Gy). Human papillomavirus (HPV)-associated p16-expression was assessed retrospectively in tumour tissues from patients with oropharyngeal carcinoma. Results: There was no significant difference in loco-regional control (LRC) between AF and CF (log-rank test p = 0.75). LRC at 5 years was 65.5% for AF and 64.9% for CF. Overall survival (OS) was similar in both arms (p = 0.99). The estimated cancer specific survival (CSS) at 5 years was 62.2% (AF) and 63.3% (CF) (p = 0.99). 206 specimens were analysed for p16 with 153 specimens (74%) identified as p16+. P16 status did not discriminate for response to AF vs. CF with regard to LRC, OS or CSS. Patients with p16+ tumours had a statistically significant better overall prognosis compared with p16 tumours. Conclusion: This update confirms the results of the 2-year report. We failed to identify a positive effect resulting from AF with regards to LRC, OS and CSS. The addition of information on the HPV-associated p16 overexpression did not explain this lack of effect.
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