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Deaths from lung cancer exceed those from any other type of malignancy, with 1·5 million deaths in 2010. Prevention and smoking cessation are still the main methods to reduce the death toll. The US National Lung Screening Trial, which compared CT screening with chest radiograph, yielded a mortality advantage of 20% to participants in the CT group. International debate is ongoing about whether sufficient evidence exists to implement CT screening programmes. When questions about effectiveness and cost-effectiveness have been answered, which will await publication of the largest European trial, NELSON, and pooled analysis of European CT screening trials, we discuss the main topics that will need consideration. These unresolved issues are risk prediction models to identify patients for CT screening; radiological protocols that use volumetric analysis for indeterminate nodules; options for surgical resection of CT-identified nodules; screening interval; and duration of screening. We suggest that a demonstration project of biennial screening over a 4-year period should be undertaken.

ObjectivesTo develop and evaluate a fully automatic method to measure diameters of the ascending and descending aorta on non-ECG-gated, non-contrast computed tomography (CT) scans.Material and methodsThe method combines multi-atlas registration to obtain seed points, aorta centerline extraction, and an optimal surface segmentation approach to extract the aorta surface around the centerline. From the extracted 3D aorta segmentation, the diameter of the ascending and descending aorta was calculated at cross-sectional slices perpendicular to the extracted centerline, at the level of the pulmonary artery bifurcation, and at 1-cm intervals up to 3 cm above and below this level. Agreement with manual annotations was evaluated by dice similarity coefficient (DSC) for segmentation overlap, mean surface distance (MSD), and intra-class correlation (ICC) of diameters on 100 CT scans from a lung cancer screening trial. Repeatability of the diameter measurements was evaluated on 617 baseline-one year follow-up CT scan pairs.ResultsThe agreement between manual and automatic segmentations was good with 0.95 ± 0.01 DSC and 0.56 ± 0.08 mm MSD. ICC between the diameters derived from manual and from automatic segmentations was 0.97, with the per-level ICC ranging from 0.87 to 0.94. An ICC of 0.98 for all measurements and per-level ICC ranging from 0.91 to 0.96 were obtained for repeatability.ConclusionThis fully automatic method can assess diameters in the thoracic aorta reliably even in non-ECG-gated, non-contrast CT scans. This could be a promising tool to assess aorta dilatation in screening and in clinical practice.Key Points• Fully automatic method to assess thoracic aorta diameters.• High agreement between fully automatic method and manual segmentations.• Method is suitable for non-ECG-gated CT and can therefore be used in screening.

Background The societies of thoracic surgery are working to incorporate simulation and competency-based assessment into specialty training. One challenge is the development of a simulation-based test, which can be used as an assessment tool. The study objective was to establish validity evidence for a virtual reality simulator test of a video-assisted thoracoscopic surgery (VATS) lobectomy of a right upper lobe. Methods Participants with varying experience in VATS lobectomy were included. They were familiarized with a virtual reality simulator (LapSim ® ) and introduced to the steps of the procedure for a VATS right upper lobe lobectomy. The participants performed two VATS lobectomies on the simulator with a 5-min break between attempts. Nineteen pre-defined simulator metrics were recorded. Results Fifty-three participants from nine different countries were included. High internal consistency was found for the metrics with Cronbach’s alpha coefficient for standardized items of 0.91. Significant test–retest reliability was found for 15 of the metrics ( p -values <0.05). Significant correlations between the metrics and the participants VATS lobectomy experience were identified for seven metrics ( p -values <0.001), and 10 metrics showed significant differences between novices (0 VATS lobectomies performed) and experienced surgeons (>50 VATS lobectomies performed). A pass/fail level defined as approximately one standard deviation from the mean metric scores for experienced surgeons passed none of the novices (0 % false positives) and failed four of the experienced surgeons (29 % false negatives). Conclusion This study is the first to establish validity evidence for a VATS right upper lobe lobectomy virtual reality simulator test. Several simulator metrics demonstrated significant differences between novices and experienced surgeons and pass/fail criteria for the test were set with acceptable consequences. This test can be used as a first step in assessing thoracic surgery trainees’ VATS lobectomy competency.

BackgroundSpecific assessment tools can accelerate trainees’ learning through structured feedback and ensure that trainees attain the knowledge and skills required to practice as competent, independent surgeons (competency-based surgical education). The objective was to develop an assessment tool for video-assisted thoracoscopic surgery (VATS) lobectomy by achieving consensus within an international group of VATS experts.MethodThe Delphi method was used as a structured process for collecting and distilling knowledge from a group of internationally recognized VATS experts. Opinions were obtained in an iterative process involving answering repeated rounds of questionnaires. Responses to one round were summarized and integrated into the next round of questionnaires until consensus was reached.ResultsThirty-one VATS experts were included and four Delphi rounds were conducted. The response rate for each round were 68.9% (31/45), 100% (31/31), 96.8% (30/31), and 93.3% (28/30) for the final round where consensus was reached. The first Delphi round contained 44 items and the final VATS lobectomy Assessment Tool (VATSAT) comprised eight items with rating anchors: (1) localization of tumor and other pathological tissue, (2) dissection of the hilum and veins, (3) dissection of the arteries, (4) dissection of the bronchus, (5) dissection of lymph nodes, (6) retrieval of lobe in bag, (7) respect for tissue and structures, and (8) technical skills in general.ConclusionA novel and dedicated assessment tool for VATS lobectomy was developed based on VATS experts’ consensus. The VATSAT can support the learning of VATS lobectomy by providing structured feedback and help supervisors make the important decision of when trainees have acquired VATS lobectomy competencies for independent performance.

BackgroundCompetency-based training has gained ground in surgical training and with it assessment tools to ensure that training objectives are met. Very few assessment tools are available for evaluating performance in thoracoscopic procedures. Video recordings would provide the possibility of blinded assessment and limited rater bias. This study aimed to provide validity evidence for a newly developed and dedicated tool for assessing competency in Video-Assisted Thoracoscopic Surgery (VATS) lobectomy.MethodsParticipants with varying experience with VATS lobectomy were included from different countries. Video recordings from participants’ performance of a VATS right upper lobe lobectomy on a virtual reality simulator were rated by three raters using a modified version of a newly developed VATS lobectomy assessment tool (the VATSAT) and analyzed in relation to the unitary framework (content, response process, internal structure, relation to other variables, and consequences of testing).ResultsFifty-three participants performed two consecutive simulated VATS lobectomies on the virtual reality simulator, leaving a total of 106 videos. Content established in previously published studies. Response process Standardized data collection was ensured by using an instructional element, uniform data collection, a special rating program, and automatic generation of the results to a database. Raters were carefully instructed in using the VATSAT, and tryout ratings were carried out. Internal structure Inter-rater reliability was calculated as intra-class correlation coefficients, to 0.91 for average measures (p < 0.001). Test/re-test reliability was calculated as Pearson’s r of 0.70 (p < 0.001). G-coefficient was calculated to be 0.79 with two procedures and three raters. By performing D-theory was found that either three procedures rated by two raters or five procedures rated by one rater were enough to reach an acceptable G-coefficient of ≥ 0.8. Relation to other variables Significant differences between groups were found (p < 0.001). The participants’ VATS lobectomy experience correlated significantly to their VATSAT score (p = 0.016). Consequences of testing The pass/fail score was found to be 14.9 points by the contrasting groups’ method, leaving five false positive (29%) and six false negatives (43%).ConclusionValidity evidence was provided for the VATSAT according to the unitary framework. The VATSAT provides supervisors and assessors with a procedure-specific assessment tool for evaluating VATS lobectomy performance and aids with the decision of when the trainee is ready for unsupervised performance.

Planetary materials show systematic variations in their nucleosynthetic isotope compositions that resonate with orbital distance. The origin of this pattern remains debated, limiting how these isotopic signatures can be used to trace the precursors of terrestrial planets. Here we test the hypothesis that interstellar ices carried supernova-produced nuclides by searching for a supernova nucleosynthetic fingerprint in aqueous alteration minerals from carbonaceous and non-carbonaceous chondrite meteorites. We focus on zirconium, a refractory element that includes the neutron-rich isotope 96 Zr formed in core-collapse supernovae. Leaching experiments reveal extreme 96 Zr enrichments in alteration minerals, showing that they incorporated supernova material hosted in interstellar ices. We show that the Solar System’s zirconium isotope variability reflects mixing between these ices and an ice-free rocky component. Finally, the presence of supernova nuclides in a volatile carrier supports models where the Solar System’s nucleosynthetic variability was imparted by thermal processing of material in the protoplanetary disk and during planetary accretion. This study shows that supernova material was delivered to the early Solar System by interstellar ices, explaining isotope variations and revealing that even inner planets like Earth and Mars accreted water-rich material from the outer Solar System.

Objectives Lung cancer risk models should be externally validated to test generalizability and clinical usefulness. The Danish Lung Cancer Screening Trial (DLCST) is a population-based prospective cohort study, used to assess the discriminative performances of the PanCan models. Methods From the DLCST database, 1,152 nodules from 718 participants were included. Parsimonious and full PanCan risk prediction models were applied to DLCST data, and also coefficients of the model were recalculated using DLCST data. Receiver operating characteristics (ROC) curves and area under the curve (AUC) were used to evaluate risk discrimination. Results AUCs of 0.826–0.870 were found for DLCST data based on PanCan risk prediction models. In the DLCST, age and family history were significant predictors ( p  = 0.001 and p  = 0.013). Female sex was not confirmed to be associated with higher risk of lung cancer; in fact opposing effects of sex were observed in the two cohorts. Thus, female sex appeared to lower the risk ( p  = 0.047 and p  = 0.040) in the DLCST. Conclusions High risk discrimination was validated in the DLCST cohort, mainly determined by nodule size. Age and family history of lung cancer were significant predictors and could be included in the parsimonious model. Sex appears to be a less useful predictor. Key points • High accuracy in logistic modelling for lung cancer risk stratification of nodules. • Lung cancer risk prediction is primarily based on size of pulmonary nodules. • Nodule spiculation, age and family history of lung cancer are significant predictors. • Sex does not appear to be a useful risk predictor.

Refractory inclusions [calcium–aluminum-rich inclusions, (CAIs)] represent the oldest Solar System solids and provide information regarding the formation of the Sun and its protoplanetary disk. CAIs contain evidence of now extinct short-lived radioisotopes (e.g., 26 Al, 41 Ca, and 182 Hf) synthesized in one or multiple stars and added to the protosolar molecular cloud before or during its collapse. Understanding how and when short-lived radioisotopes were added to the Solar System is necessary to assess their validity as chronometers and constrain the birthplace of the Sun. Whereas most CAIs formed with the canonical abundance of 26 Al corresponding to 26 Al/ 27 Al of ∼5 × 10 −5 , rare CAIs with fractionation and unidentified nuclear isotope effects (FUN CAIs) record nucleosynthetic isotopic heterogeneity and 26 Al/ 27 Al of <5 × 10 −6 , possibly reflecting their formation before canonical CAIs. Thus, FUN CAIs may provide a unique window into the earliest Solar System, including the origin of short-lived radioisotopes. However, their chronology is unknown. Using the 182 Hf– 182 W chronometer, we show that a FUN CAI recording a condensation origin from a solar gas formed coevally with canonical CAIs, but with 26 Al/ 27 Al of ∼3 × 10 −6 . The decoupling between 182 Hf and 26 Al requires distinct stellar origins: steady-state galactic stellar nucleosynthesis for 182 Hf and late-stage contamination of the protosolar molecular cloud by a massive star(s) for 26 Al. Admixing of stellar-derived 26 Al to the protoplanetary disk occurred during the epoch of CAI formation and, therefore, the 26 Al– 26 Mg systematics of CAIs cannot be used to define their formation interval. In contrast, our results support 182 Hf homogeneity and chronological significance of the 182 Hf– 182 W clock.

BackgroundThe effects of low-dose CT screening on disease stage shift, mortality and overdiagnosis are unclear. Lung cancer findings and mortality rates are reported at the end of screening in the Danish Lung Cancer Screening Trial.Methods4104 men and women, healthy heavy smokers/former smokers were randomised to five annual low-dose CT screenings or no screening. Two experienced chest radiologists read all CT scans and registered the location, size and morphology of nodules. Nodules between 5 and 15 mm without benign characteristics were rescanned after 3 months. Growing nodules (>25% volume increase and/or volume doubling time<400 days) and nodules >15 mm were referred for diagnostic workup. In the control group, lung cancers were diagnosed and treated outside the study by the usual clinical practice.ResultsParticipation rates were high in both groups (screening: 95.5%; control: 93.0%; p<0.001). Lung cancer detection rate was 0.83% at baseline and mean annual detection rate was 0.67% at incidence rounds (p=0.535). More lung cancers were diagnosed in the screening group (69 vs 24, p<0.001), and more were low stage (48 vs 21 stage I–IIB non-small cell lung cancer (NSCLC) and limited stage small cell lung cancer (SCLC), p=0.002), whereas frequencies of high-stage lung cancer were the same (21 vs 16 stage IIIA–IV NSCLC and extensive stage SCLC, p=0.509). At the end of screening, 61 patients died in the screening group and 42 in the control group (p=0.059). 15 and 11 died of lung cancer, respectively (p=0.428).ConclusionCT screening for lung cancer brings forward early disease, and at this point no stage shift or reduction in mortality was observed. More lung cancers were diagnosed in the screening group, indicating some degree of overdiagnosis and need for longer follow-up.

ObjectiveTo examine the psychosocial consequences of being allocated to the control group as compared with the screen group in a randomised lung cancer screening trial.MethodThe Danish Lung Cancer Screening Trial, a randomised controlled trial, ran from 2004 to 2010 with the purpose of investigating the benefits and harms of lung cancer screening. The participants in Danish Lung Cancer Screening Trial were randomised to either the control group or the screen group and were asked to complete the questionnaires Consequences Of Screening and Consequences Of Screening in Lung Cancer (COS-LC). The Consequences Of Screening and the COS-LC were used to examine the psychosocial consequences of participating in the study, by comparing the control and the screen groups' responses at the prevalence and at the incidence round.ResultsThere was no statistically significant difference in socio-demographic characteristics or smoking habits between the two groups. Responses to the COS-LC collected before the incidence round were statistically significantly different on the scales ‘anxiety’, ‘behaviour’, ‘dejection’, ‘self-blame’, ‘focus on airway symptoms’ and ‘introvert’, with the control group reporting higher negative psychosocial consequences. Furthermore, the participants in both the control and the screen groups exhibited a mean increase in negative psychosocial consequences when their responses from the prevalence round were compared with their responses from the first incidence round.ConclusionsParticipation in a randomised controlled trial on lung cancer screening has negative psychosocial consequences for the apparently healthy participants—both the participants in the screen group and the control group. This negative impact was greatest for the control group.