Smoking-related lung abnormalities on computed tomography images: comparison with pathological findings

Association between interstitial lung abnormality and mortality in patients with esophageal cancer

PURPOSE

To investigate the relationship between interstitial lung abnormalities (ILAs) and mortality in patients with esophageal cancer and the cause of mortality.

MATERIALS AND METHODS

This retrospective study investigated patients with esophageal cancer from January 2011 to December 2015. ILAs were visually scored on baseline CT using a 3-point scale (0 = non-ILA, 1 = indeterminate for ILA, and 2 = ILA). ILAs were classified into subcategories of non-subpleural, subpleural non-fibrotic, and subpleural fibrotic. Five-year overall survival (OS) was compared between patients with and without ILAs using the multivariable Cox proportional hazards model. Subgroup analyses were performed based on cancer stage and ILA subcategories. The prevalences of treatment complications and death due to esophageal cancer and pneumonia/respiratory failure were analyzed using Fisher's exact test.

RESULTS

A total of 478 patients with esophageal cancer (age, 66.8 years ± 8.6 [standard deviation]; 64 women) were evaluated in this study. Among them, 267 patients showed no ILAs, 125 patients were indeterminate for ILAs, and 86 patients showed ILAs. ILAs were a significant factor for shorter OS (hazard ratio [HR] = 1.68, 95% confidence interval [CI] 1.10-2.55, P = 0.016) in the multivariable Cox proportional hazards model adjusting for age, sex, smoking history, clinical stage, and histology. On subgroup analysis using patients with clinical stage IVB, the presence of ILAs was a significant factor (HR = 3.78, 95% CI 1.67-8.54, P = 0.001). Subpleural fibrotic ILAs were significantly associated with shorter OS (HR = 2.22, 95% CI 1.25-3.93, P = 0.006). There was no significant difference in treatment complications. Patients with ILAs showed a higher prevalence of death due to pneumonia/respiratory failure than those without ILAs (non-ILA, 2/95 [2%]; ILA, 5/39 [13%]; P = 0.022). The prevalence of death due to esophageal cancer was similar in patients with and without ILA (non-ILA, 82/95 [86%]; ILA 32/39 [82%]; P = 0.596).

CONCLUSION

ILAs were significantly associated with shorter survival in patients with esophageal cancer.

Advances in COPD imaging using CT and MRI: linkage with lung physiology and clinical outcomes

Recent years have witnessed major advances in lung imaging in patients with COPD. These include significant refinements in images obtained by computed tomography (CT) scans together with the introduction of new techniques and software that aim for obtaining the best image whilst using the lowest possible radiation dose. Magnetic resonance imaging (MRI) has also emerged as a useful radiation-free tool in assessing structural and more importantly functional derangements in patients with well-established COPD and smokers without COPD, even before the existence of overt changes in resting physiological lung function tests. Together, CT and MRI now allow objective quantification and assessment of structural changes within the airways, lung parenchyma and pulmonary vessels. Furthermore, CT and MRI can now provide objective assessments of regional lung ventilation and perfusion, and multinuclear MRI provides further insight into gas exchange; this can help in structured decisions regarding treatment plans. These advances in chest imaging techniques have brought new insights into our understanding of disease pathophysiology and characterising different disease phenotypes. The present review discusses, in detail, the advances in lung imaging in patients with COPD and how structural and functional imaging are linked with common resting physiological tests and important clinical outcomes.

Smoking-Related Interstitial Fibrosis and Smoker's Macrophages

Smoking-related interstitial lung diseases (SRILDs) are a group of heterogeneous diffuse pulmonary parenchymal diseases associated with tobacco exposure. Smoking-related interstitial fibrosis (SRIF) is relatively recent, a pathologically defined form of SRILDs. SRIF is characterized by the accumulation of macrophages in the alveolar spaces, which is associated with interstitial inflammation and fibrosis. The macrophages frequently contain light brown pigment and are called 'smoker's macrophages'. Patients with SRIF who have clinical evidence of interstitial lung disease are most commonly relatively young, heavy smokers with abnormalities on chest computed tomography showing ground-glass opacities, peripheral consolidation, and reticulation. Although SRIF is caused by cigarette smoking, the exact pathophysiological mechanisms by which smoking causes this type of interstitial fibrosis remain unknown. The degree of fibrosis and appearance of macrophage aggregates are important points of distinction when evaluating and diagnosing SRIF. Macrophage heterogeneity, particularly the activation and function of monocyte-derived alveolar macrophages (Mo-AMs) and interstitial macrophages (IMs), has important implications for the pathogenesis of SRIF and developing treatments. Further researches focused on smoker's macrophages are needed to understand of the pathogenesis of SRIF.

Pulmonary Pathology Society Survey on Practice Approaches in the Histologic Diagnosis of Fibrotic Interstitial Lung Disease: Consensus and Opportunities

CONTEXT.—

The pathologic diagnosis of usual interstitial pneumonia (UIP) remains a challenging area, and application of histologic UIP guidelines has proved difficult.

OBJECTIVE.—

To understand current practice approaches by pulmonary pathologists for the histologic diagnosis of UIP and other fibrotic interstitial lung diseases (ILDs).

DESIGN.—

The Pulmonary Pathology Society (PPS) ILD Working Group developed and sent a 5-part survey on fibrotic ILD electronically to the PPS membership.

RESULTS.—

One hundred sixty-one completed surveys were analyzed. Of the respondents, 89% reported using published histologic features in clinical guidelines for idiopathic pulmonary fibrosis (IPF) in their pathologic diagnosis; however, there was variability in reporting terminology, quantity and quality of histologic features, and the use of guideline categorization. Respondents were very likely to have access to pulmonary pathology colleagues (79%), pulmonologists (98%), and radiologists (94%) to discuss cases. Half of respondents reported they may alter their pathologic diagnosis based on additional clinical and radiologic history if it is pertinent. Airway-centered fibrosis, granulomas, and types of inflammatory infiltrates were considered important, but there was poor agreement on how these features are defined.

CONCLUSIONS.—

There is significant consensus among the PPS membership on the importance of histologic guidelines/features of UIP. There are unmet needs for (1) consensus and standardization of diagnostic terminology and incorporation of recommended histopathologic categories from the clinical IPF guidelines into pathology reports, (2) agreement on how to incorporate into the report relevant clinical and radiographic information, and (3) defining the quantity and quality of features needed to suggest alternative diagnoses.

Impact of accurate diagnosis of interstitial lung diseases on postoperative outcomes in lung cancer

OBJECTIVE

The prognostic impact of interstitial lung disease (ILD) subclassification based on both high-resolution computed tomography (HRCT) scan findings and histopathological findings is unknown.

METHODS

We retrospectively analyzed 104 patients who were diagnosed with clinical ILD according to HRCT scan findings and who underwent lung cancer surgery. Via an expert multidisciplinary discussion, we re-classified HRCT scan findings and validated the histopathological patterns of ILDs in lung specimens.

RESULTS

There were several mismatches between HRCT scan findings and histological patterns. Moreover, 87 (83.7%) and 6 (5.8%) patients were diagnosed with definitive ILD and pathological non-ILD, respectively. Finally, 82 patients with idiopathic interstitial pneumonias (IIPs) were divided into the idiopathic pulmonary fibrosis (IPF) (n = 61) group and the other group (n = 21). The 5-year overall survival rate of the IPF group was significantly lower than that of the other group (22.8% vs 67.9%; p = 0.011). Sub-classification of IIPs was found to be an independent prognostic factor for overall survival in patients with lung cancer.

CONCLUSION

An accurate diagnosis of IIPs/IPF according to both HRCT scan findings and histological patterns is important for providing an appropriate treatment among patients with lung cancer who presented with clinical ILD.

Smoking-related interstitial lung disease

Exposure to smoke is associated with the development of diseases of the airways and lung parenchyma. Apart from chronic obstructive pulmonary disease (COPD), in some individuals, tobacco smoke can also trigger mechanisms of interstitial damage that result in various pathological changes and pulmonary fibrosis. A causal relation has been established between tobacco smoke and a group of entities that includes respiratory bronchiolitis-associated interstitial lung disease (RB-ILD), desquamative interstitial pneumonia (DIP), Langerhans cell histiocytosis (LCH), and acute eosinophilic pneumonia (AEP). Smoking is considered a risk factor for idiopathic pulmonary fibrosis (IPF); however, the role and impact of smoking in the development of this differentiated clinical entity, which has also been called combined pulmonary fibrosis and emphysema (CPFE) as well as nonspecific interstitial pneumonia (NIP), remains to be determined. The definition of smoking-related interstitial fibrosis (SRIF) is relatively recent, with differentiated histological characteristics. The likely interconnection between the mechanisms involved in inflammation and pulmonary fibrosis in all these processes often results in an overlapping of clinical, radiological, and histological features in the same patient that can sometimes lead to radiological patterns of interstitial lung disease that are impossible to classify. For this reason, a combined approach to diagnosis is recommendable. This combined approach should be based on the joint interpretation of the histological and radiological findings while taking the clinical context into consideration. This paper aims to describe the high-resolution computed tomography (HRCT) findings in this group of disease entities in correlation with the clinical manifestations and histological changes underlying the radiological pattern.

Centri-lobular pulmonary nodules on HRCT: incidence and approach for etiological diagnosis

Background

Centri-lobular nodules are the most common pattern of diffuse pulmonary nodules encountered on high-resolution computed tomography (HRCT). HRCT with post-processing techniques such as obtaining maximum intensity projection (MIP) is helpful in making centri-lobular nodules more conspicuous. The study aimed to highlight the role of HRCT with its reconstruction capabilities in the detection and characterization of centri-lobular pulmonary nodules, interpret the most frequent associated findings, and correlate with the clinical findings to reach the most appropriate diagnosis.

Results

The study included 58 patients; 41.4% males and 58.6% females. Their age ranged from 2 to 67 years with mean age of 25.69. The centri-lobular nodules numbers, distribution, shape, and associated HRCT chest findings were identified. The top three etiological diagnoses were infection/inflammation in 50.0% of cases followed by acute viral bronchiolitis in 27.6% and inhalation bronchiolitis in 19.0% of cases. Correlation of HRCT findings with the clinical diagnosis was carried out with consequent formulation of an algorithm for the diagnostic approach of various etiologies of centri-lobular pulmonary nodules.

Conclusions

HRCT is a useful tool in the detection and characterization of centri-lobular pulmonary nodules. It can be used to differentiate the different etiologies that share centri-lobular nodularity. Other associated features and multidisciplinary approach are essential for further characterization of the most relevant etiological diagnosis.

Cigarette Smoke Particle-Induced Lung Injury and Iron Homeostasis

It is proposed that the mechanistic basis for non-neoplastic lung injury with cigarette smoking is a disruption of iron homeostasis in cells after exposure to cigarette smoke particle (CSP). Following the complexation and sequestration of intracellular iron by CSP, the host response (eg, inflammation, mucus production, and fibrosis) attempts to reverse a functional metal deficiency. Clinical manifestations of this response can present as respiratory bronchiolitis, desquamative interstitial pneumonitis, pulmonary Langerhans’ cell histiocytosis, asthma, pulmonary hypertension, chronic bronchitis, and pulmonary fibrosis. If the response is unsuccessful, the functional deficiency of iron progresses to irreversible cell death evident in emphysema and bronchiectasis. The subsequent clinical and pathological presentation is a continuum of lung injuries, which overlap and coexist with one another. Designating these non-neoplastic lung injuries after smoking as distinct disease processes fails to recognize shared relationships to each other and ultimately to CSP, as well as the common mechanistic pathway (ie, disruption of iron homeostasis).

Sarcoidosis, the master mimicker

Sarcoidosis is an idiopathic multisystem disorder characterized by noncaseating granulomas. The article focuses on the typical imaging manifestations of sarcoid and the common differentials that need to be included when appropriate. Mistaking a sarcoid-mimicking disease for sarcoid can result in increased patient morbidity and mortality. The pulmonary system is the most common system involved and is typically the best understood by the radiologist, however a deeper knowledge of the pulmonary findings and features of sarcoid in other organ systems is critical. There is a myriad of sarcoid imaging manifestations that can involve every organ system. Often a confidant diagnosis of sarcoid can be made, however a broad differential may need to be considered- differential diagnoses include primary neoplasm, metastatic disease, infectious, and inflammatory etiologies. Radiologist familiarity with the multimodality multisystem imaging findings of sarcoid can help guide clinical management and optimize patient care.

A primer for understanding radiology articles about machine learning and deep learning

The application of machine learning and deep learning in the field of imaging is rapidly growing. Although the principles of machine and deep learning are unfamiliar to the majority of clinicians, the basics are not so complicated. One of the major issues is that commentaries written by experts are difficult to understand, and are not primarily written for clinicians. The purpose of this article was to describe the different concepts behind machine learning, radiomics, and deep learning to make clinicians more familiar with these techniques.

Comparison of Clinical Measures Among Interstitial Lung Disease (ILD) Patients with Usual Interstitial Pneumonia (UIP) Patterns on High-Resolution Computed Tomography

PURPOSE

Idiopathic Pulmonary Fibrosis is a progressive and fatal interstitial lung disease (ILD) characterized by a typical radiographic or histologic usual interstitial pneumonia (UIP) pattern. In 2018, diagnostic categories of UIP based on computed tomography patterns were revised by the Fleischner Society. The study aimed to describe differences in comorbidities and spirometry in ILD patients that were characterized by high-resolution computed tomography (HRCT) images as having a typical, probable, indeterminate, and alternative diagnosis of UIP.

METHODS

We retrospectively studied 80 ILD patients from 2017 to 2019. Typical UIP was defined using the Fleischner Society diagnostic criteria for IPF. Atypical UIP was reached by consensus after a multidisciplinary clinical-radiological-pathological review of patient data. Baseline characteristics, comorbidities, and spirometry were compared among the four subgroups.

RESULTS

Among 80 patients, 59% were male, 61% had a history of smoking, and the mean age was 67.7 ± 10 years (SD). A typical UIP pattern was more frequently observed among patients with chronic obstructive pulmonary disease (COPD) (p < 0.001) and pulmonary hypertension (p = 0.03). Of 30 patients with COPD, 14 had emphysema, while 10 had IPF. After adjusting for forced expiratory volume in one second (FEV₁) in liters, change of FEV₁% from baseline to 6-12 months, age, and sex, only COPD remained significantly associated with typical UIP (p = 0.018). Tobacco use was not significantly associated with any radiographic type (p = 0.199).

CONCLUSION

Typical UIP was prevalent among COPD/emphysema patients. Although smoking has a strong association with IPF, we did not find a significant association with smoking and typical UIP in our cohort.

CA-125, CA-153, and CYFRA21-1 as clinical indicators in male lung cancer with ocular metastasis

Despite recent improvements in diagnosis and therapy, lung cancer remains the most common malignant tumor in males, with high morbidity and mortality. As the annual incidence continues to increase worldwide, the prognosis for male patients with lung cancer remains unsatisfactory. Interestingly, smoking is associated with lung cancer and ocular lesions by altering risk factors such as carbohydrate antigen (CA)-125, CA-153 and cytokeratin-19 fragment (CYFRA21-1). A diagnostic standard for serum biomarker levels of ocular metastasis (OM) in males with lung cancer is therefore urgently needed. In this retrospective analysis, we examined the relationship between smoking preference and OM in male patients with lung cancer to identify an independent prognostic factor or establish a quantitative indicated standard for OM using the clinical indexes from 2238 cases of male lung cancer. The combination of CA-125, CA-153 and CYFRA21-1 could help diagnose OM in male lung cancer patients. This finding might lead to more timely diagnosis and effective therapies.