Observational Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Radiol. Sep 28, 2015; 7(9): 294-305
Published online Sep 28, 2015. doi: 10.4329/wjr.v7.i9.294
Pulmonary fibrosis and emphysema: Is the emphysema type associated with the pattern of fibrosis?
Anastasia Oikonomou, Paraskevi Mintzopoulou, Argyris Tzouvelekis, Petros Zezos, George Zacharis, Anastasios Koutsopoulos, Demosthenes Bouros, Panos Prassopoulos
Anastasia Oikonomou, Paraskevi Mintzopoulou, Panos Prassopoulos, Department of Radiology, Democritus University of Thrace, Dragana, 68100 Alexandroupolis, Greece
Anastasia Oikonomou, Department of Medical Imaging, Sunnybrook Health Sciences Centre, Toronto M4N 3M5, Canada
Argyris Tzouvelekis, George Zacharis, Demosthenes Bouros, Department of Pneumonology, Democritus University of Thrace, Dragana, 68100 Alexandroupolis, Greece
Argyris Tzouvelekis, Yale School of Medicine, Department of Internal Medicine, Section of Pulmonary, Critical Care and Sleep Medicine, New Haven, CT 06511, United States
Petros Zezos, Department of Endoscopic Unit, Democritus University of Thrace, Dragana, 68100 Alexandroupolis, Greece
Petros Zezos, Department of Internal Medicine, Division of Gastroenterology, Sunnybrook Health Sciences Centre, Toronto M4N 3M5, Canada
Anastasios Koutsopoulos, Department of Pathology, Democritus University of Thrace, Dragana, 68100 Alexandroupolis, Greece
Anastasios Koutsopoulos, Department of Pathology, University of Herakleion, Voutes, 71003 Heraklion, Greece
Author contributions: Oikonomou A designed the research; Oikonomou A, Mintzopoulou P evaluated the CT studies; Mintzopoulou P, Tzouvelekis A performed the literature research; Tzouvelekis A and Zacharis G performed the functional evaluation of the patients and gathered the clinical information from the patients’ records; Oikonomou A, Mintzopoulou P, Tzouvelekis A, Zezos P and Zacharis G analyzed the data; Zezos P performed the statistical analysis; Koutsopoulos A evaluated the histologic specimens and analyzed the histologic results; Oikonomou A wrote the paper; Mintzopoulou P, Tzouvelekis A, Zezos P, Zacharis G and Koutsopoulos A edited the paper; Bouros D and Prassopoulos P critically evaluated the final version of the manuscript.
Institutional review board statement: The study was reviewed and approved by the Institutional Review Board of the University Hospital of Alexandroupolis, Greece.
Informed consent statement: According to our country’s legislation, informed consent is not needed for retrospective analysis of data corresponding to current practice.
Conflict-of-interest statement: No conflict of interest realated to this manuscript was declared by any of the authors.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Anastasia Oikonomou, MD, PhD, Department of Medical Imaging, Sunnybrook Health Sciences Centre, AG 271b - 2075 Bayview Avenue, Toronto M4N 3M5, Canada. anastasia.oikonomou@sunnybrook.ca
Telephone: +1-416-4806100 Fax: +1-416-4805855
Received: January 22, 2015
Peer-review started: January 23, 2015
First decision: March 6, 2015
Revised: June 30, 2015
Accepted: August 16, 2015
Article in press: August 17, 2015
Published online: September 28, 2015
Abstract

AIM: To investigate whether the predominant emphysema type is associated with the high resolution computed tomography (HRCT) pattern of fibrosis in combined pulmonary fibrosis and emphysema (CPFE).

METHODS: Fifty-three smokers with upper lobe emphysema and lower lobe pulmonary fibrosis on - HRCT - were retrospectively evaluated. Patients were stratified into 3 groups according to the predominant type of emphysema: Centrilobular (CLE), paraseptal (PSE), CLE = PSE. Patients were also stratified into 3 other groups according to the predominant type of fibrosis on HRCT: Typical usual interstitial pneumonia (UIP), probable UIP and nonspecific interstitial pneumonia (NSIP). HRCTs were scored at 5 predetermined levels for the coarseness of fibrosis (Coarseness), extent of emphysema (emphysema), extent of interstitial lung disease (TotExtILD), extent of reticular pattern not otherwise specified (RetNOS), extent of ground glass opacity with traction bronchiectasis (extGGOBx), extent of pure ground glass opacity and extent of honeycombing. HRCT mean scores, pulmonary function tests, diffusion capacity (DLCO) and systolic pulmonary arterial pressure were compared among the groups.

RESULTS: The predominant type of emphysema was strongly correlated with the predominant type of fibrosis. The centrilobular emphysema group exhibited a significantly higher extent of emphysema (P < 0.001) and a lower extent of interstitial lung disease (P < 0.002), reticular pattern not otherwise specified (P < 0.023), extent of ground glass opacity with traction bronchiectasis (P < 0.002), extent of honeycombing (P < 0.001) and coarseness of fibrosis (P < 0.001) than the paraseptal group. The NSIP group exhibited a significantly higher extent of emphysema (P < 0.05), total lung capacity (P < 0.01) and diffusion capacity (DLCO) (P < 0.05) than the typical UIP group. The typical UIP group exhibited a significantly higher extent of interstitial lung disease, extent of reticular pattern not otherwise specified, extent of ground glass opacity with traction bronchiectasis, extent of honeycombing and coarseness of fibrosis (0.039 > P > 0.000). Although the pulmonary arterial pressure was higher in typical UIP group relative to the NSIP group, the difference was not statistically significant.

CONCLUSION: In CPFE patients, paraseptal emphysema is associated more with UIP-HRCT pattern and higher extent of fibrosis than centrilobular emphysema.

Keywords: Emphysema, Pulmonary fibrosis, High resolution computed tomography, Centrilobular, Paraseptal, Nonspecific interstitial pneumonia pattern, Usual interstitial pneumonia pattern

Core tip: This study aimed to investigate whether the predominant type of emphysema is associated with the pattern of fibrosis in combined pulmonary fibrosis and emphysema (CPFE). Patients were stratified into 3 groups according to predominant type of emphysema and fibrosis. High resolution computed tomography (HRCT) was retrospectively scored at 5 levels for various morphologic parameters characterizing emphysema and fibrosis. The predominant type of emphysema was strongly correlated with the predominant type of fibrosis. The centrilobular emphysema group exhibited a higher extent of emphysema and a lower extent of fibrosis. In CPFE, paraseptal emphysema was more associated with a UIP-HRCT pattern and a higher extent of fibrosis than was centrilobular emphysema.