Smoking-related Interstitial Lung Disease: Radiologic-Clinical-Pathologic Correlation

Abstract

Cigarette smoking is a recognized risk factor for development of interstitial lung disease (ILD). There is strong evidence supporting a causal role for cigarette smoking in development of respiratory bronchiolitis ILD (RB-ILD), desquamative interstitial pneumonitis (DIP), and pulmonary Langerhans cell histiocytosis (PLCH). In addition, former and current smokers may be at increased risk for developing idiopathic pulmonary fibrosis (IPF). The combination of lower lung fibrosis and upper lung emphysema is being increasingly recognized as a distinct clinical entity in smokers. High-resolution computed tomography is sensitive for detection and characterization of ILD and may allow recognition and classification of the smoking-related ILDs (SR-ILDs) into distinct individual entities. However, the clinical, radiologic, and histologic features overlap among the different SR-ILDs, and mixed patterns of disease frequently coexist in the same patient. The overlap is most significant between RB-ILD and DIP. Macrophage accumulation is bronchiolocentric in RB-ILD, producing centrilobular ground-glass opacity, and more diffuse in DIP, producing widespread ground-glass changes. The coexistence of upper lung nodules and cysts in a smoker allows confident diagnosis of PLCH. Final diagnosis of an SR-ILD and identification of the specific entity can be achieved with certainty only after the pulmonologist, radiologist, and pathologist have reviewed all of the clinical, radiologic, and pathologic data.

Interstitial lung diseases in a lung cancer screening trial

“…KEYWORDS: Cigarette smoking, computed tomography, interstitial lung disease, lung cancer, screening C igarette smoking is a recognised risk factor for the development of interstitial lung disease (ILD) [1][2][3]. The spectrum of thin-section computed tomography (CT) abnormalities associated with cigarette smoking was first defined by REMY-JARDIN and coworkers [4,5], and since then it has widened continuously.…”

Respiratory Bronchiolitis With Fibrosis–Interstitial Lung Disease: A New Form of Smoking-Induced Interstitial Lung Disease

“…The usual belief, based mostly on pathologic findings, is that RBILD can progress to desquamative interstitial pneumonia 7,8,12 (ie, the localized peribronchiolar accumulation of smoker's macrophages in RBILD spreads to encompass more and more of the parenchyma, eventuating in disease in which large portions of the lung are filled with smoker's macrophages, and in which there is also some amount of interstitial fibrosis and interstitial inflammation; Figure 2). Not all authors accept this scenario, and some believe that RBILD and DIP are separate entities.…”

Smoking and Other Interstitial Lung Diseases

“…It is a characterized finding in the high-resolution CT (HRCT), the presence of areas ground-glass attenuation [34] that is correlated histologically with the alveolar filling by macrophages [35] (Figure 1). DIP affects mainly peripheral lower lung areas [36]. Fibrosis may be present in 50-60% of the patients [34,35], but honeycombing is rare [17].…”

“…Upper lobe centrilobular emphysema could be associated [35] and honeycombing is rare [42]. The differential diagnosis includes acute hypersensitivity pneumonitis, DIP and NSIP [36].…”

“…The differential diagnosis of nodules observed in HRCT includes sarcoidosis, silicosis, metastatic disease, and tuberculosis. Cystic disease should be distinguished from lymphangioleiomyomatosis, emphysema, and idiopathic pulmonary fibrosis [36].…”