Measurement of airway inflammation in current smokers by positron emission tomography

• Published in: Clinical physiology and functional imaging Vol. 39; no. 6; pp. 393 - 398
• Main Authors: Garpered, Sabine, Minarik, David, Diaz, Sandra, Valind, Sven, Edenbrandt, Lars, Wollmer, Per
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01.11.2019
• Subjects: Abnormalities; Adult; Aged; Animal tissues; burden; Chronic obstructive pulmonary disease; Clinical Medicine; Computed tomography; copd; Density; Female; Fluorine isotopes; Fluorodeoxyglucose F18 - administration & dosage; Fluorodeoxyglucose F18 - pharmacokinetics; Humans; Inflammation; Klinisk medicin; Leukocytes; Leukocytes (neutrophilic); lung; Lung - diagnostic imaging; Lung - immunology; Lung - metabolism; Lung cancer; lung density; Lung diseases; Lungs; Male; Medical and Health Sciences; Medicin och hälsovetenskap; Middle Aged; Obstructive lung disease; pet; Physiology; Pneumonia - diagnostic imaging; Pneumonia - immunology; Pneumonia - metabolism; Positron emission; Positron emission tomography; Positron Emission Tomography Computed Tomography; Predictive Value of Tests; Prospective Studies; pulmonary inflammation; Radiologi och bildbehandling; Radiology, Nuclear Medicine and Medical Imaging; Radiopharmaceuticals - administration & dosage; Radiopharmaceuticals - pharmacokinetics; Reproducibility of Results; Respiratory tract; Respiratory tract diseases; Smokers; Smoking; Smoking - adverse effects; Smoking - immunology; Tissue Distribution; Tomography; computed tomography; lung density; positron emission tomography; chronic obstructive pulmonary disease
• ISSN: 1475-0961; 1475-097X; 1475-097X
• DOI: 10.1111/cpf.12590

Summary Background Accumulation of activated neutrophilic leucocytes is known to increase uptake of 18F‐fluorodeoxyglucose (18F‐FDG) into lung tissue. Available evidence suggests that smokers and subjects with chronic obstructive pulmonary disease (COPD) have neutrophilic inflammation in peripheral airways. The aim of this study was to examine whether current smokers have higher lung tissue uptake of 18F‐FDG than never‐smokers when correcting for air fraction of the lungs. Methods We prospectively recruited 33 current smokers and 33 never‐smokers among subjects referred for diagnosis or staging of cancer, other than lung cancer, with combined positron emission tomography/computed tomography (PET/CT) with 18F‐FDG. Subjects with focal 18F‐FDG uptake or focal CT abnormalities in the lungs were excluded. The lungs were segmented in the CT image, and lung density measured. 18F‐FDG uptake was measured in the corresponding volume and corrected for air fraction. Results Lung uptake of 18F‐FDG, corrected for air fraction, was 12·5 and 8 per cent higher in the right and left lungs, respectively, in current smokers than in never‐smokers (P<0·05). Conclusion Abnormal lung tissue uptake of 18F‐FDG may be masked by reduced lung density if the uptake is not related to air fraction. Increased uptake of 18F‐FDG in lung tissue in current smokers relative to never‐smokers may reflect inflammation in peripheral airways. Measurements of 18F‐FDG uptake in the lung tissue may be useful for animal and human studies of airways disease in COPD and the relation between airway and systemic inflammation.