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Introduction: Non-small-cell lung cancer (NSCLC) guidelines advise to screen stage III NSCLC patients for brain metastases (BMs), preferably by magnetic resonance imaging (MRI) or when contraindicated or not accessible a dedicated contrast enhanced-computed tomography (dCE-CT), which can be incorporated in the staging 18 Fluodeoxoglucose-positron emission tomography ( 18 FDG-PET-CE-CT). In daily practice, often a dCE-CT is performed instead of a MRI. The aim of the current study is to evaluate the additive value of MRI after dCE-CT, incorporated in the 18 FDG-PET-CE-CT., Patients and Methods: It is an observational prospective multicentre study (NTR3628). Inclusion criteria included stage III NSCLC patients with a dCE-CT of the brain incorporated in the 18 FDG-PET and an additional MRI of the brain. Primary end-point is percentage of patients with BM on MRI without suspect lesions on dCE-CT. Secondary end-points are percentage of patients with BM on dCE-CT and percentage of patients with BM ≤ 1 year of a negative staging MRI., Results: Sixteen (7%) patients with extracranial stage III had BM on dCE-CT and were excluded. One hundred forty-nine patients were enrolled. 7/149 (4.7%) had BM on MRI without suspect lesions on dCE-CT. One hundred eighteen patients had a follow-up of at least 1 year (four with BM on baseline MRI); eight of the remaining 114 (7%) patients developed BM ≤ 1 year after a negative staging brain MRI., Conclusion: Although in 7% of otherwise stage III NSCLC patients, BMs were detected on staging dCE-CT, MRI brain detected BMs in an additional 4.7%, which we consider clinically relevant. Within 1 year after a negative staging MRI, 7% developed BM., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: 18 F-Fluorodeoxyglucose (FDG) positron-emission tomography/computed tomography (PET/CT) was recently introduced as a new tool for the diagnosis of prosthetic heart valve endocarditis (PVE). Previous studies reporting a modest diagnostic accuracy may have been hampered by unstandardized image acquisition and assessment, and several confounders, as well. The aim of this study was to improve the diagnostic performance of FDG PET/CT in patients in whom PVE was suspected by identifying and excluding possible confounders, using both visual and standardized quantitative assessments., Methods: In this multicenter study, 160 patients with a prosthetic heart valve (median age, 62 years [43-73]; 68% male; 82 mechanical valves; 62 biological; 9 transcatheter aortic valve replacements; 7 other) who underwent FDG PET/CT for suspicion of PVE, and 77 patients with a PV (median age, 73 years [65-77]; 71% male; 26 mechanical valves; 45 biological; 6 transcatheter aortic valve replacements) who underwent FDG PET/CT for other indications (negative control group), were retrospectively included. Their scans were reassessed by 2 independent observers blinded to all clinical data, both visually and quantitatively on available European Association of Nuclear Medicine Research Ltd-standardized reconstructions. Confounders were identified by use of a logistic regression model and subsequently excluded., Results: Visual assessment of FDG PET/CT had a sensitivity/specificity/positive predictive value/negative predictive value for PVE of 74%/91%/89%/78%, respectively. Low inflammatory activity (C-reactive protein <40 mg/L) at the time of imaging and use of surgical adhesives during prosthetic heart valve implantation were significant confounders, whereas recent valve implantation was not. After the exclusion of patients with significant confounders, diagnostic performance values of the visual assessment increased to 91%/95%/95%/91%. As a semiquantitative measure of FDG uptake, a European Association of Nuclear Medicine Research Ltd-standardized uptake value ratio of ≥2.0 was a 100% sensitive and 91% specific predictor of PVE., Conclusions: Both visual and quantitative assessments of FDG PET/CT have a high diagnostic accuracy in patients in whom PVE is suspected. FDG PET/CT should be implemented early in the diagnostic workup to prevent the negative confounding effects of low inflammatory activity (eg, attributable to prolonged antibiotic therapy). Recent valve implantation was not a significant predictor of false-positive interpretations, but surgical adhesives used during implantation were.