Customized bioresorbable airway stents with elasticity similar to silicone were 3D printed by digital light processing.

Stent placement has been established as a standard procedure for treating airway obstructions. Other indications are localized malacias and fistulas. Though many different stents with various diameters and lengths are available, the shapes are hardly ever ideal because of the distorted anatomy in patients with diseased airways. There are technical and legal limitations for customizing purchased airway stents. Individually tailored stents would be preferable. New techniques of additive manufacturing such as 3D printing make it possible to produce optimized stents for a particular patient. Using CT data and bronchoscopic images, stents can be constructed that match a particular anatomical situation and apply the optimized expansion force. We give an overview of the currently available manufacturing techniques for polymeric stents and report about our own experience. Direct on-site printing of polyurethane stents in a hospital and printing individual extrusion molds for silicone stents in a certified cleanroom are both feasible. Furthermore, there are promising attempts of combining mechanically customized stents with surface modifications, drug-eluting features, biodegradability, and time-dependent adaptation (4D printing). Truly optimized airway stents with the potential of solving the well-known stent problems such as granulation tissue formation, remodeling, mucostasis, and infections are in reach. The technical hurdles are probably easier to overcome than the legal constraints. The legal situations are discussed from a physician's and a manufacturer's perspective.

Purpose: Immune-checkpoint inhibitors (ICI) present a new treatment for malignancies by boosting the immune system. This has led to a variety of immune-related adverse events, including ICI-associated pneumonitis (ICIaP). Diagnosis thereof is often challenging, and its pathogenesis has not yet been fully understood. The aim of this cross-sectional case–control study was to investigate cytokines in serum and bronchoalveolar lavage fluid (BALF) expressed in patients with ICIaP compared to controls consisting of healthy individuals, patients with lung cancer and patients with interstitial lung diseases (ILD) other than ICIaP. Methods: From January 2018 until June 2019, 401 adult patients with various lung diseases were prospectively enrolled in a BALF- and serum biobank, called BALOTHEK. Of these, 12 patients were diagnosed with ICIaP (Pembrolizumab, Ipilimumab, or both, and Durvalumab) serving as case group. Subjects with one of three diagnosis groups from BALOTHEK, including lung cancer, ILD other than ICIaP, and healthy individuals, served as matched controls. The following 11 cytokines were simultaneously analyzed in BALF and serum of each study participant: interferon gamma, tumor necrosis factor alpha, interleukin (IL) 1b, IL-2, IL-4, IL-5, IL-6, IL-8, IL-12p70, IL-13 and IL-17A. This study was approved by the local ethic review committee (BASEC-ID 2017-02,307 and 2018-01,724). Results: Absolute number and percentage of lymphocytes in BALF of patients with ICIaP were significantly higher compared to control groups. For the investigated cytokines in BALF, a significant increase of IL-6 level was shown for patients with ICIaP compared to control groups (p = 0.031, adjusted for multiple comparisons). Conclusion: Cytokine profile assessed in BALF shows promising potential for facilitating diagnosis and understanding of pathophysiology of ICIaP. IL-6 may not only contribute to better understanding of pathophysiology but also herald therapeutic implications for Tocilizumab.

Objectives There is uncertainty about patient selection and the adequate timing at which fluorine-18 fluorodeoxyglucose (¹⁸F-FDG) PET/computed tomography (CT) is indicated in the diagnostic work-up of fever of unknown origin (FUO). The aim of this study was to determine the diagnostic performance of ¹⁸F-FDG PET/CT in patients with FUO. Methods All consecutive patients who underwent ¹⁸F-FDG PET/CT at the University Hospital Zurich because of FUO between 2006 and 2012 were included in this retrospective, observational study. Results A total of 76 patients [70% men, median (interquartile range) age 60 (47–67) years] were included. ¹⁸F-FDG PET/CT showed characteristically increased ¹⁸F-FDG activity in 56 patients (74%), leading to confirmation of or change in the suspected cause of FUO in 57 and 17%, respectively. The final diagnosis after ¹⁸F-FDG PET/CT included infection (21%), malignancy (22%), noninfectious inflammatory disease (12%), others (5%), or an unknown cause (40%). The success rate, sensitivity, and specificity of ¹⁸F-FDG PET/CT were 60, 77, and 31%, respectively. Sensitivity was highest in patients with suspected malignancy (100%, 95% confidence interval 79–100%). Diagnostic performance was independent of the investigated variables other than suspected infection as a cause of FUO (odds ratio 0.1, 95% confidence interval 0.01–0.8, P=0.033). Conclusion The diagnostic performance of ¹⁸F-FDG PET/CT was significantly higher in patients with suspected malignancy causing a FUO compared with suspected infection or noninfectious inflammatory disease. However, it was independent of the baseline characteristics and duration of fever. This supports the recommendation to perform ¹⁸F-FDG PET/CT early in the diagnostic work-up of FUO, which may shorten disease duration and lower health costs, particularly when infection or malignancy is suspected.