•Current lung cancer radiotherapy planning does not account for regional variation in pulmonary function.•Regional lung function can be quantified through derivation of ventilation obtained from 4DCT ...imaging.•In this study dose to highly ventilated lung was found to be associated with symptomatic pneumonitis.•These findings provide important metrics to be used in functional lung avoidance radiotherapy planning and in designing clinical trials.
To identify metrics of radiation dose delivered to highly ventilated lung that are predictive of radiation-induced pneumonitis.
A cohort of 90 patients with locally advanced non-small cell lung cancer treated with standard fractionated radiation therapy (RT) (60–66 Gy in 30–33 fractions) were evaluated. Regional lung ventilation was determined from pre-RT 4-dimensional computed tomography (4DCT) using the Jacobian determinant of a B-spline deformable image registration to estimate lung tissue expansion during respiration. Multiple voxel-wise population- and individual-based thresholds for defining high functioning lung were considered. Mean dose and volumes receiving dose ≥ 5–60 Gy were analyzed for both total lung-ITV (MLD,V5-V60) and highly ventilated functional lung-ITV (fMLD,fV5-fV60). The primary endpoint was symptomatic grade 2+ (G2+) pneumonitis. Receiver operator curve (ROC) analyses were used to identify predictors of pneumonitis.
G2+ pneumonitis occurred in 22.2% of patients, with no differences between stage, smoking status, COPD, or chemo/immunotherapy use between G<2 and G2+ patients (P≥ 0.18). Highly ventilated lung was defined as voxels exceeding the population-wide median of 18% voxel-level expansion. All total and functional metrics were significantly different between patients with and without pneumonitis (P≤ 0.039). Optimal ROC points predicting pneumonitis from functional lung dose were fMLD ≤ 12.3 Gy, fV5 ≤ 54% and fV20 ≤ 19 %. Patients with fMLD ≤ 12.3 Gy had a 14% risk of developing G2+ pneumonitis whereas risk significantly increased to 35% for those with fMLD > 12.3 Gy (P = 0.035).
Dose to highly ventilated lung is associated with symptomatic pneumonitis and treatment planning strategies should focus on limiting dose to functional regions. These findings provide important metrics to be used in functional lung avoidance RT planning and designing clinical trials.
Nowadays, taking into account the multidimensionality of the external environment and necessity of the sustainable development of human resources, organizations are obliged to take more care of the ...psychological resources of their employees, e.g., positive orientation, ego resilience, and emotional stability. Such resources affect how we cope with stress and a sense of threat. The authors of this paper focus on people employed in the aviation sector, who work in the hard-to-cope environment of full automation, demanding working conditions and numerous stressors. The presented study fills a gap in the research on the psychological characteristics of the aviation sector. Moreover, a sense of stress/threat is described in the context of the high specificity of employees representing the 4.0 sector. Therefore, it provides additional insights into the psychological functioning of the employees in the aviation sector. The results show that both positive orientation and ego resilience might be seen as protective factors against a sense of threat and stress, while a type D personality is a risk factor of a higher level of those psychological states. The novelty of the presented research concerns a better understanding of the sense of stress/threat experienced by the employees in this sector, as well as verifying the relationships between psychological variables described in the literature as personal resources.
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