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Purpose: In this work, we adapt a method based on multiple hypothesis tracking (MHT) that has been shown to give state‐of‐the‐art vessel segmentation results in interactive settings, for the purpose of extracting trees. Methods: Regularly spaced tubular templates are fit to image data forming local hypotheses. These local hypotheses are then used to construct the MHT tree, which is then traversed to make segmentation decisions. Some critical parameters in the method, we base ours on, are scale‐dependent and have an adverse effect when tracking structures of varying dimensions. We propose to use statistical ranking of local hypotheses in constructing the MHT tree which yields a probabilistic interpretation of scores across scales and helps alleviate the scale dependence of MHT parameters. This enables our method to track trees starting from a single seed point. Results: The proposed method is evaluated on chest computed tomography data to extract airway trees and coronary arteries and compared to relevant baselines. In both cases, we show that our method performs significantly better than the Original MHT method in semiautomatic setting. Conclusions: The statistical ranking of local hypotheses introduced allows the MHT method to be used in noninteractive settings yielding competitive results for segmenting tree structures. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Low dose computerised tomography (CT) screening for lung cancer can reduce lung-cancer-specific mortality. The objective of this study was to analyse healthcare costs and healthcare utilisation of participants in the Danish lung cancer CT-screening trial (DLCST). Materials and methods: This registry study was nested in a randomised controlled trial (DLCST). 4104 participants, current or former heavy smokers, aged 50–70 years were randomised to five annual low dose CT scans or usual care during 2004–2010. Total healthcare costs and healthcare utilisation data for both the primary and the secondary healthcare sector were retrieved from public registries from randomisation – September 2011 and compared between (1) the CT-screening group and the control group and, (2) the control group and each of the true-positive, false-positive and true-negative groups. Results: The median annual costs per participant were significantly higher in the CT-screening group (Euros [EUR] 1342, interquartile range [IQR] 750–2980) compared with the control group (EUR 1190, IQR 590–2692) (p <0.0001). When the cost of the CT-screening programme was excluded, there was no longer a statistically significant difference between the CT-screening group (EUR 1155, IQR 567–2798) and the control group (p =0.52). Analyses according to the diagnostic groups showed that annual costs were 10.57 (95% CI 7.09–15.75) times higher for the true-positive and 1.67 (95% CI 1.20–2.32) times higher for the false-positive group compared with the control group. Conclusion: Low dose lung cancer CT screening increases healthcare costs compared with no screening; this difference was attributable to the costs of the CT-screening programme. Overall healthcare costs were higher for the true-positive and false-positive groups than for the control group, also when excluding the cost of the CT-screening programme. This increase was outweighed by the larger true-negative group showing no significant differences in costs compared with the control group. [Copyright &y& Elsevier]

• It is recommended to start rehabilitation two weeks after lung cancer surgery. • To avoid a decrease in HRQoL start up exercise two weeks after lung cancer surgery. • Starting exercise 14 weeks post-surgery did not improve HRQoL to the same level. Patients with lung cancer report a lower degree of Health Related Quality of Life (HRQoL) compared with other cancer patients. HRQoL reflects how patients experience the impact of their disease and its treatment on their quality of daily living. A widely used questionnaire in lung cancer patients is the Functional Assessment of Cancer Therapy – Lung (FACT-L) questionnaire. Here we report the secondary outcomes on FACT-L data from the Postoperative Rehabilitation in Operation for Lung CAncer (PROLUCA) study, which describes the effect of early (14 days) versus late initiated (14 weeks) postoperative rehabilitation. The PROLUCA study was designed as a two-armed randomized controlled trial with an early rehabilitation group (14 days after surgery (ERG)) or a control arm with a late rehabilitation group (14 weeks after surgery (LRG)). The results for seven domain scores obtained using the FACT-L at the following time-points: baseline, 14 weeks, 26 weeks and 52 weeks after surgery are presented here. 119 patients were randomized to the ERG and 116 to the LRG. In the ERG, HRQoL measured by both FACT-L and FACT-G (general core instrument) showed a continuous improvement up to 26 weeks after which HRQoL decreased after further 26 weeks without structured intervention. In the LRG a non-significant deterioration was detected over the first 14 weeks after surgery. After participation in the 12 weeks rehabilitation program, an increase in HRQoL was seen, without reaching the same level as the early group. Analyses of the seven domain scores obtained using FACT-L and FACT-G reflect the importance of starting exercise early after surgery since the ERG avoid a temporary decrease in HRQoL. It is therefore recommended to start up a structured rehabilitation program 14 days after surgery, containing high intensity interval training and strength exercise twice a week for 12 weeks. [ABSTRACT FROM AUTHOR]

Although the descending aortic diameter is larger in smokers, data about thoracic aortic growth is missing. Our aim is to present the distribution of thoracic aortic growth in smokers and to compare it with literature of the general population. Current and ex-smokers aged 50–70 years from the longitudinal Danish Lung Cancer Screening Trial, were included. Mean and 95th percentile of annual aortic growth of the ascending aortic (AA) and descending aortic (DA) diameters were calculated with the first and last non-contrast computed tomography scans during follow-up. Determinants of change in aortic diameter over time were investigated with linear mixed models. A total of 1987 participants (56% male, mean age 57.4 ± 4.8 years) were included. During a median follow-up of 48 months, mean AA and DA growth rates were comparable between males (AA 0.12 ± 0.31 mm/year and DA 0.10 ± 0.30 mm/year) and females (AA 0.11 ± 0.29 mm/year and DA 0.13 ± 0.27 mm/year). The 95th percentile ranged from 0.42 to 0.47 mm/year, depending on sex and location. Aortic growth was comparable between current and ex-smokers and aortic growth was not associated with pack-years. Our findings are consistent with aortic growth rates of 0.08 to 0.17 mm/years in the general population. Larger aortic growth was associated with lower age, increased height, absence of medication for hypertension or hypercholesterolemia and lower Agatston scores. This longitudinal study of smokers in the age range of 50–70 years shows that ascending and descending aortic growth is approximately 0.1 mm/year and is consistent with growth in the general population. • In current and ex-smokers, the ascending and descending aorta grows on average 0.1 mm/year • Aortic growth was comparable between current and ex-smokers and was not associated with pack-years • Thoracic aortic growth in smokers is consistent with cross-sectional data from the general population • Annual growth did not statistically significantly differ between males and females • Based on 95th percentiles, aortic growth of 0.5 mm/year can be considered the upper limit of normal [ABSTRACT FROM AUTHOR]

Optimal surface methods are a class of graph cut methods posing surface estimation as an n-ary ordered labeling problem. They are used in medical imaging to find interacting and layered surfaces optimally and in low order polynomial time. Representing continuous surfaces with discrete sets of labels, however, leads to discretization errors and, if graph representations are made dense, excessive memory usage. Limiting memory usage and computation time of graph cut methods are important and graphs that locally adapt to the problem has been proposed as a solution. Min-marginal energies computed using dynamic graph cuts offer a way to estimate solution uncertainty and these uncertainties have been used to decide where graphs should be adapted. Adaptive graphs, however, introduce extra parameters, complexity, and heuristics. We propose a way to use min-marginal energies to estimate continuous solution labels that does not introduce extra parameters and show empirically on synthetic and medical imaging datasets that it leads to improved accuracy. The increase in accuracy was consistent and in many cases comparable with accuracy otherwise obtained with graphs up to eight times denser, but with proportionally less memory usage and improvements in computation time. [ABSTRACT FROM AUTHOR]

Highlights • Effect of exercise postoperative rehabilitation with operable lung cancer. • To reduce fatigue patients should be recommended to initiate early exercise programs. • No differences between the groups after 26 weeks. Abstract Introduction: Little is known about the optimal amount and timing of exercise strain in concern of the operation wound and with regard improvement of physical function and quality of life (QOL) after surgery for lung cancer. On this background, we decided to investigate the effect of early vs. late initiated postoperative rehabilitation in patients with operable lung cancer on exercise capacity, functional capacity, muscle strength, and QOL. Methods: The study was designed as a two-armed randomized controlled trial with randomization to either early initiated postoperative rehabilitation (14 days after surgery (ERG)) or a control arm with late initiated postoperative rehabilitation (14 weeks after surgery (LRG)). The primary endpoint was a change in maximum oxygen consumption (VO2peak) from baseline to post intervention 26 weeks following lung resection. Fatigue was measured with EORTC QLQ C30 LC13. Results: From April 2013 to June 2016, 582 patients with operable NSCLC were screened for eligibility. With 119 patients randomized in the early rehabilitation group (ERG) and 116 randomized to late rehabilitation group (LRG). There was no significant difference from baseline to 26 weeks between ERG and LRG (p = 0.926). There was a significant difference from baseline to 14 weeks between groups (p = 0.0018). There was a significant difference from 14 weeks to 26 weeks between the two groups (p < 0.001). We found no significant differences in QOL but we found a significant difference between ERG and LRG from baseline to 14 weeks in fatigue level in favour of ERG. Conclusion: This is the first randomized controlled trial to investigate the effects of early vs. late initiated postoperative rehabilitation in patients with lung cancer. There is no difference in the commencement (early vs. late) of a postoperative exercise program for patients with lung cancer on exercise capacity. But to reduce fatigue patients should be recommended to initiate early exercise programs. [ABSTRACT FROM AUTHOR]

Lung cancer screening with low-dose CT can save lives. This European Union (EU) position statement presents the available evidence and the major issues that need to be addressed to ensure the successful implementation of low-dose CT lung cancer screening in Europe. This statement identified specific actions required by the European lung cancer screening community to adopt before the implementation of low-dose CT lung cancer screening. This position statement recommends the following actions: a risk stratification approach should be used for future lung cancer low-dose CT programmes; that individuals who enter screening programmes should be provided with information on the benefits and harms of screening, and smoking cessation should be offered to all current smokers; that management of detected solid nodules should use semi-automatically measured volume and volume-doubling time; that national quality assurance boards should be set up to oversee technical standards; that a lung nodule management pathway should be established and incorporated into clinical practice with a tailored screening approach; that non-calcified baseline lung nodules greater than 300 mm3, and new lung nodules greater than 200 mm3, should be managed in multidisciplinary teams according to this EU position statement recommendations to ensure that patients receive the most appropriate treatment; and planning for implementation of low-dose CT screening should start throughout Europe as soon as possible. European countries need to set a timeline for implementing lung cancer screening. [ABSTRACT FROM AUTHOR]

Objectives: Screening for lung cancer should be limited to a high-risk-population, and abnormalities in low-dose computed tomography (CT) screening images may be relevant for predicting the risk of lung cancer. Our aims were to compare the occurrence of visually detected emphysema and interstitial abnormalities in subjects with and without lung cancer in a screening population of smokers.Methods: Low-dose chest CT examinations (baseline and latest possible) of 1990 participants from The Danish Lung Cancer Screening Trial were independently evaluated by two observers who scored emphysema and interstitial abnormalities. Emphysema (lung density) was also measured quantitatively.Results: Emphysema was seen more frequently and its extent was greater among participants with lung cancer on baseline (odds ratio (OR), 1.8, p = 0.017 and p = 0.002) and late examinations (OR 2.6, p < 0.001 and p < 0.001). No significant difference was found using quantitative measurements. Interstitial abnormalities were more common findings among participants with lung cancer (OR 5.1, p < 0.001 and OR 4.5, p < 0.001).There was no association between presence of emphysema and presence of interstitial abnormalities (OR 0.75, p = 0.499).Conclusions: Even early signs of emphysema and interstitial abnormalities are associated with lung cancer. Quantitative measurements of emphysema-regardless of type-do not show the same association.Key Points: • Visually detected emphysema on CT is more frequent in individuals who develop lung cancer. • Emphysema grading is higher in those who develop lung cancer. • Interstitial abnormalities, including discrete changes, are associated with lung cancer. • Quantitative lung density measurements are not useful in lung cancer risk prediction. • Early CT signs of emphysema and interstitial abnormalities can predict future risk. [ABSTRACT FROM AUTHOR]

Background: The purpose of the PROLUCA study is to investigate the efficacy of preoperative and early postoperative rehabilitation in a non-hospital setting in patients with operable lung cancer with special focus on exercise. Methods: Using a 2×2 factorial design with continuous effect endpoint (Maximal Oxygen Uptake (VO2peak)), 380 patients with non-small cell lung cancer (NSCLC) stage I-IIIa referred for surgical resection will be randomly assigned to one of four groups: (1) preoperative and early postoperative rehabilitation (starting two weeks after surgery); (2) preoperative and late postoperative rehabilitation (starting six weeks after surgery); (3) early postoperative rehabilitation alone; (4) today's standard care which is postoperative rehabilitation initiated six weeks after surgery. The preoperative rehabilitation program consists of an individually designed, 30-minute home-based exercise program performed daily. The postoperative rehabilitation program consists of a supervised group exercise program comprising cardiovascular and resistance training two-hour weekly for 12 weeks combined with individual counseling. The primary study endpoint is VO2peak and secondary endpoints include: Six-minute walk distance (6MWD), one-repetition-maximum (1RM), pulmonary function, patient-reported outcomes (PROs) on health-related quality of life (HRQoL), symptoms and side effects of the cancer disease and the treatment of the disease, anxiety, depression, wellbeing, lifestyle, hospitalization time, sick leave, work status, postoperative complications (up to 30 days after surgery) and survival. Endpoints will be assessed at baseline, the day before surgery, pre-intervention, post-intervention, six months after surgery and one year after surgery. Discussion: The results of the PROLUCA study may potentially contribute to the identification of the optimal perioperative rehabilitation for operable lung cancer patients focusing on exercise initiated immediately after diagnosis and rehabilitation shortly after surgery. [ABSTRACT FROM AUTHOR]

Background The purpose of the PROLUCA study is to investigate the efficacy of preoperative and early postoperative rehabilitation in a non-hospital setting in patients with operable lung cancer with special focus on exercise. Methods Using a 2x2 factorial design with continuous effect endpoint (Maximal Oxygen Uptake (VO2peak)), 380 patients with non-small cell lung cancer (NSCLC) stage I-IIIa referred for surgical resection will be randomly assigned to one of four groups: (1) preoperative and early postoperative rehabilitation (starting two weeks after surgery); (2) preoperative and late postoperative rehabilitation (starting six weeks after surgery); (3) early postoperative rehabilitation alone; (4) today's standard care which is postoperative rehabilitation initiated six weeks after surgery. The preoperative rehabilitation program consists of an individually designed, 30-minute home-based exercise program performed daily. The postoperative rehabilitation program consists of a supervised group exercise program comprising cardiovascular and resistance training two-hour weekly for 12 weeks combined with individual counseling. The primary study endpoint is VO2peak and secondary endpoints include: Six-minute walk distance (6MWD), one-repetition-maximum (1RM), pulmonary function, patient-reported outcomes (PROs) on health-related quality of life (HRQoL), symptoms and side effects of the cancer disease and the treatment of the disease, anxiety, depression, wellbeing, lifestyle, hospitalization time, sick leave, work status, postoperative complications (up to 30 days after surgery) and survival. Endpoints will be assessed at baseline, the day before surgery, pre-intervention, post-intervention, six months after surgery and one year after surgery. Discussion The results of the PROLUCA study may potentially contribute to the identification of the optimal perioperative rehabilitation for operable lung cancer patients focusing on exercise initiated immediately after diagnosis and rehabilitation shortly after surgery. [ABSTRACT FROM AUTHOR]

Progressive decline in lung function has been widely accepted as the hallmark of chronic obstructive pulmonary disease (COPD); however, recent evidence indicates that the rate of decline measured as decline in forced expiratory volume in one second (FEV1) is higher in mild to moderate COPD than in severe COPD. Usually changes in FEV1 are measured in ml that is 'absolute'; however, changes can also be measured 'relative' as a percentage of the actual FEV1. We hypothesize that relative measurements could be more appropriate than absolute measurements for describing changes in lung function. We analyzed data from 3,218 relatively healthy heavy smokers who participated in the Danish Lung Cancer Screening Trial. The influences of age, sex, height, body mass index, smoking, and severity of airflow limitation on FEV1 were analyzed in mixed effects models. In absolute terms those with the best lung function consistently showed the steepest decline, whereas in relative terms most fast decliners are found among those with low lung function. Measuring changes in relative terms implied statistically significant acceleration of decline with advancing age, smoking (pack-years) and severity of airflow limitation. Relative measurements may lead to a better understanding of changes in lung function. Smoking and severity of airflow limitation speed up the loss of lung function, and this emphasizes the importance of abstaining from smoking the sooner the better. Measuring changes in relative terms could have important implications for the interpretation of results from clinical trials where FEV1 is the primary outcome. DLCST; , registration number: NCT00496977. [ABSTRACT FROM AUTHOR]

This study presents a fully automatic, data-driven approach for texture-based quantitative analysis of chronic obstructive pulmonary disease (COPD) in pulmonary computed tomography (CT) images. The approach uses supervised learning where the class labels are, in contrast to previous work, based on measured lung function instead of on manually annotated regions of interest (ROIs). A quantitative measure of COPD is obtained by fusing COPD probabilities computed in ROIs within the lung fields where the individual ROI probabilities are computed using a k nearest neighbor (kNN) classifier. The distance between two ROIs in the kNN classifier is computed as the textural dissimilarity between the ROIs, where the ROI texture is described by histograms of filter responses from a multi-scale, rotation invariant Gaussian filter bank. The method was trained on 400 images from a lung cancer screening trial and subsequently applied to classify 200 independent images from the same screening trial. The texture-based measure was significantly better at discriminating between subjects with and without COPD than were the two most common quantitative measures of COPD in the literature, which are based on density. The proposed measure achieved an area under the receiver operating characteristic curve (AUC) of 0.713 whereas the best performing density measure achieved an AUC of 0.598. Further, the proposed measure is as reproducible as the density measures, and there were indications that it correlates better with lung function and is less influenced by inspiration level. [ABSTRACT FROM PUBLISHER]

Abstract: Introduction: Participation bias might affect the results and the representability of randomised controlled trials. We investigated the degree of socio-demographic and psychosocial participation bias in the Danish Lung Cancer Screening Trial (DLCST). Methods: In DLCST the questionnaire COS-LC (Consequences of Screening in Lung Cancer) was used to measure the psychosocial aspects of screening. To investigate a difference with a comparable representative sample from the Danish population, we sent out an inclusion questionnaire to 3999 Danes in the age from 50 to 70 years randomly selected from the Central National Register. Those who completed the inclusion questionnaire and met the inclusion criteria from DLCST received the COS-LC. Those who completed the COS-LC–and thus formed a population sample comparable to DLCST – were compared to the DLCST participants on socio-demographics and psychosocial measures. Results: Participation rates were high among the comparable population sample: 75.3% completed the inclusion questionnaire and 77.4% of those who were eligible completed the COS-LC. The analyses revealed differences between the DLCST participants and the comparable population sample in the following socio-demographic aspects: social group, living alone, gender, age and geographical area. DLCST participants reported less negative psychosocial aspects than the comparable population sample. Conclusion: The present study has shown substantial socio-demographic and psychosocial participation bias in DLCST. [Copyright &y& Elsevier]

Background: The purpose of the PROLUCA study is to investigate the efficacy of preoperative and early postoperative rehabilitation in a non-hospital setting in patients with operable lung cancer with special focus on exercise.Methods: Using a 2 x 2 factorial design with continuous effect endpoint (Maximal Oxygen Uptake (VO2peak)), 380 patients with non-small cell lung cancer (NSCLC) stage I-IIIa referred for surgical resection will be randomly assigned to one of four groups: (1) preoperative and early postoperative rehabilitation (starting two weeks after surgery); (2) preoperative and late postoperative rehabilitation (starting six weeks after surgery); (3) early postoperative rehabilitation alone; (4) today's standard care which is postoperative rehabilitation initiated six weeks after surgery. The preoperative rehabilitation program consists of an individually designed, 30-minute home-based exercise program performed daily. The postoperative rehabilitation program consists of a supervised group exercise program comprising cardiovascular and resistance training two-hour weekly for 12 weeks combined with individual counseling. The primary study endpoint is VO2peak and secondary endpoints include: Six-minute walk distance (6MWD), one-repetition-maximum (1RM), pulmonary function, patient-reported outcomes (PROs) on health-related quality of life (HRQoL), symptoms and side effects of the cancer disease and the treatment of the disease, anxiety, depression, wellbeing, lifestyle, hospitalization time, sick leave, work status, postoperative complications (up to 30 days after surgery) and survival. Endpoints will be assessed at baseline, the day before surgery, pre-intervention, post-intervention, six months after surgery and one year after surgery.Discussion: The results of the PROLUCA study may potentially contribute to the identification of the optimal perioperative rehabilitation for operable lung cancer patients focusing on exercise initiated immediately after diagnosis and rehabilitation shortly after surgery.Trial Registration: NCT01893580. [ABSTRACT FROM AUTHOR]