Features of COPD as Predictors of Lung Cancer

Thoracic high resolution computed tomography evaluation of imaging abnormalities of 108 lung cancer patients with different pulmonary function

PURPOSE

Preserved ratio impaired spirometry (PRISm) and chronic obstructive pulmonary disease (COPD) belong to lung function injury. PRISm is a precursor to COPD. We compared and evaluated the different basic information, imaging findings and survival curves of 108 lung cancer patients with different pulmonary function based on high resolution computed tomography (HRCT).

METHODS

This retrospective study was performed on 108 lung cancer patients who did pulmonary function test (PFT) and thoracic HRCT. The basic information was evaluated: gender, age, body mass index (BMI), smoke, smoking index (SI). The following pulmonary function findings were evaluated: forced expiratory volume in 1s (FEV1), forced vital capacity (FVC), FEV1/FVC ratio. The following computed tomography (CT) findings were evaluated: appearance (bronchiectasis, pneumonectasis, atelectasis, ground-glass opacities [GGO], interstitial inflammation, thickened bronchial wall), diameter (aortic diameter, pulmonary artery diameter, MPAD/AD ratio, inferior vena cava diameter [IVCD]), tumor (volume, classification, distribution, staging [I, II, III, IV]). Mortality rates were calculated and survival curves were estimated using the Kaplan-Meier method.

RESULTS

Compared with normal pulmonary function group, PRISm group and COPD group were predominantly male, older, smoked more, poorer lung function and had shorter survival time after diagnosis. There were more abnormal images in PRISm group and COPD group than in normal lung function group (N-C group). In PRISm group and COPD group, lung cancer was found late, and the tumor volume was larger, mainly central squamous carcinoma. But the opposite was true for the N-C group. The PRISm group and COPD group had significant poor survival probability compared with the normal lung function group.

CONCLUSIONS

Considerable differences regarding basic information, pulmonary function, imaging findings and survival curves are found between normal lung function group and lung function injury group. Lung function injury (PRISm and COPD) should be taken into account in future lung cancer screening studies.

Impaired lung function and lung cancer risk in 461 183 healthy individuals: a cohort study

BACKGROUND

It has been known that smoking and various lung diseases including lung cancer can cause lung function impairment. However, the impact of different types of lung function impairments, such as preserved ratio impaired spirometry (PRISm) and airflow obstruction (AO), on the incidence and mortality of lung cancer in both general and never-smoker populations remains unclear. We wished to examine the effect of lung function impairments on lung cancer risks.

METHODS

This was a retrospective cohort study (1 January 1994 to 31 December 2017) of individuals from a health surveillance programme in Taiwan who underwent baseline spirometry tests at the entry point. PRISm was defined as an FEV1/FVC (forced expiratory volume in 1 s/forced vital capacity) ratio >0.7 and FEV1 <0.8, while AO was defined as an FEV1/FVC ratio <0.7. Cox proportional hazards models and cubic spline curves were used to examine the associations between lung function impairments and lung cancer risks.

RESULTS

The study included 461,183 individuals, of whom 14.3% had PRISm and 7.9% had AO. A total of 4038 cases of lung cancer and 3314 lung cancer-related deaths were identified during the 23 years of follow-up. Individuals with PRISm and AO exhibited a higher risk of lung cancer incidence and mortality compared with those with normal lung function. The adjusted HRs and 95% CIs were 1.14 (1.03 to 1.26) and 1.23 (1.10 to 1.37) in the overall cohort, and 1.08 (0.93 to 1.24), and 1.23 (1.05 to 1.45) in the never-smoker cohort. The risks of both developing and dying of lung cancer increased with the severity levels of lung function impairments and lower FEV1 values.

CONCLUSION

Impaired lung function is associated with increased risks of developing lung cancer and subsequent mortality. The study highlights the importance of considering lung function in lung cancer screening for better candidate selection.

Effect of postoperative exercise training on physical function and quality of life of lung cancer patients with chronic obstructive pulmonary disease: A randomized controlled trial

BACKGROUND

Postoperative rehabilitation programs consisting of exercise training are considered effective for unselected lung cancer patients. However, whether postoperative exercise is beneficial to lung cancer patients comorbid with chronic obstructive pulmonary disease remains unknown.

METHODS

Eighty-four patients diagnosed with both lung cancer and chronic obstructive pulmonary disease were randomized into the exercise group and control group. Both groups were given standard postoperative rehabilitation for 1 week. After that, oxygen therapy (if needed) and nebulization were given to the control group, while patients in the exercise group started to participate in exercise programs on the basis of receiving oxygen therapy and nebulization as in the control group. The exercise programs consisted of 24 training sessions.

RESULTS

In both groups, the functional status and the results of the pulmonary function test decreased from baseline to the endpoint. However, after surgery and the intervention program, both the maximal oxygen consumption in the cardiopulmonary exercise test and walking distance in the 6-minute walk test in the exercise group were significantly better than those in the control group [15.5 (±1.4) mL/kg/min vs 13.1 (±1.3) mL/kg/min, P = 0.016; 437.4 (±48.6) m vs 381.7 (±40.5) m, P = 0.040]. Force vital capacity and forced expiratory volume in the first second in the exercise group were better than those in the control group, but the differences were not statistically significant [1798.1 (±298.9) mL vs 1664.0 (±329.7) mL, P = 0.254; 1155.7 (±174.3) mL vs 967.4 (±219.4) mL, P = 0.497]. The decline in the standard score of the QLQ-C30 (V3.0) was smaller in the exercise group, but the difference did not meet a statistically significant level [61.7 (±5.7) vs 58.4 (±9.3), P = 0.318].

CONCLUSION

This study demonstrates that a short-term postoperative exercise training program can facilitate the recovery of functional capacity in lung cancer patients with comorbidities of chronic obstructive pulmonary disease.

Prediction of the benign and malignant nature of masses in COPD background based on Habitat-based enhanced CT radiomics modeling: A preliminary study

BACKGROUND

It is difficult to differentiate between chronic obstructive pulmonary disease (COPD)-peripheral bronchogenic carcinoma (COPD-PBC) and inflammatory masses.

OBJECTIVE

This study aims to predict COPD-PBC based on clinical data and preoperative Habitat-based enhanced CT radiomics (HECT radiomics) modeling.

METHODS

A retrospective analysis was conducted on clinical imaging data of 232 cases of postoperative pathological confirmed PBC or inflammatory masses. The PBC group consisted of 82 cases, while the non-PBC group consisted of 150 cases. A training set and a testing set were established using a 7:3 ratio and a time cutoff point. In the training set, multiple models were established using clinical data and radiomics texture changes within different enhanced areas of the CT mass (HECT radiomics). The AUC values of each model were compared using Delong's test, and the clinical net benefit of the models was tested using decision curve analysis (DCA). The models were then externally validated in the testing set, and a nomogram of predicting COPD-PBC was created.

RESULTS

Univariate analysis confirmed that female gender, tumor morphology, CEA, Cyfra21-1, CT enhancement pattern, and Habitat-Radscore B/C were predictive factors for COPD-PBC (P< 0.05). The combination model based on these factors had significantly higher predictive performance [AUC: 0.894, 95% CI (0.836-0.936)] than the clinical data model [AUC: 0.758, 95% CI (0.685-0.822)] and radiomics model [AUC: 0.828, 95% CI (0.761-0.882)]. DCA also confirmed the higher clinical net benefit of the combination model, which was validated in the testing set. The nomogram developed based on the combination model helped predict COPD-PBC.

CONCLUSION

The combination model based on clinical data and Habitat-based enhanced CT radiomics can help differentiate COPD-PBC, providing a new non-invasive and efficient method for its diagnosis, treatment, and clinical decision-making.

When chronic obstructive pulmonary disease meets small cell lung cancer: an unusual case report of rapid progression

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease and a risk factor for lung cancer. Small cell lung cancer is a neuroendocrine tumor with a high degree of malignancy and an overall five-year survival rate of less than 7%.

CASES PRESENTATION

Herein, we report the case of an 68-year-old male presented to the respiratory department with cough, sputum, and dyspnea. He was diagnosed as community acquired pneumonia and treated with intravenous anti-infection. Previous pulmonary function was definitively diagnosed as COPD. About 7 months after discharge, the patient returned to the hospital for cough and dyspnea. After diagnosis of the tumor, cisplatin, etoposide and durvalumab were administered. Finally the patient died of respiratory failure approximately 9 months after his diagnosis.

CONCLUSIONS

For COPD patients with immunocompromised manifestations, it is necessary to be alert to complications and shorten the follow-up interval of chest CT. COPD may accelerate the formation and progression of SCLC.

Baseline characteristics from a 3-year longitudinal study to phenotype subjects with COPD: the FOOTPRINTS study

BACKGROUND

FOOTPRINTS® is a prospective, longitudinal, 3-year study assessing the association between biomarkers of inflammation/lung tissue destruction and chronic obstructive pulmonary disease (COPD) severity and progression in ex-smokers with mild-to-severe COPD. Here, we present baseline characteristics and select biomarkers of study subjects.

METHODS

The methodology of FOOTPRINTS® has been published previously. The study population included ex-smokers with a range of COPD severities (Global Initiative for Chronic Obstructive Lung Disease [GOLD] stages 1-3), ex-smokers with COPD and alpha-1-antitrypsin deficiency (A1ATD) and a control group of ex-smokers without airflow limitation (EwAL). At study entry, data were collected for: demographics, disease characteristics, history of comorbidities and COPD exacerbations, symptoms, lung function and volume, exercise capacity, soluble biomarkers, and quantitative and qualitative computed tomography. Baseline data are presented with descriptive statistical comparisons for soluble biomarkers in the individual GOLD and A1ATD groups versus EwAL.

RESULTS

In total, 463 subjects were enrolled. The per-protocol set comprised 456 subjects, mostly male (64.5%). The mean (standard deviation) age was 60.7 (6.9) years. At baseline, increasing pulmonary symptoms, worse lung function, increased residual volume, reduced diffusing capacity of the lung for carbon monoxide (DLco) and greater prevalence of centrilobular emphysema were observed with increasing disease severity amongst GOLD 1-3 subjects. Subjects with A1ATD (n = 19) had similar lung function parameters to GOLD 2-3 subjects, a high residual volume comparable to GOLD 3 subjects, and similar air trapping to GOLD 2 subjects. Compared with EwAL (n = 61), subjects with A1ATD had worse lung function, increased residual volume, reduced DLco, and a greater prevalence of confluent or advanced destructive emphysema. The soluble inflammatory biomarkers white blood cell count, fibrinogen, high-sensitivity C-reactive protein and plasma surfactant protein were higher in GOLD 1-3 groups than in the EwAL group. Interleukin-6 was expressed less often in EwAL subjects compared with subjects in the GOLD and A1ATD groups. Soluble receptor for advanced glycation end product was lowest in GOLD 3 subjects, indicative of more severe emphysema.

CONCLUSIONS

These findings provide context for upcoming results from FOOTPRINTS®, which aims to establish correlations between biomarkers and disease progression in a representative COPD population.

TRIAL REGISTRATION NUMBER

NCT02719184, study start date 13/04/2016.

Systematic analysis of various RNA transcripts and construction of biological regulatory networks at the post-transcriptional level for chronic obstructive pulmonary disease

BACKGROUND

Although chronic inflammation, oxidative stress, airway remodeling, and protease-antiprotease imbalance have been implicated in chronic obstructive pulmonary disease (COPD), the exact pathogenesis is still obscure. Gene transcription and post-transcriptional regulation have been taken into account as key regulators of COPD occurrence and development. Identifying the hub genes and constructing biological regulatory networks at the post-transcriptional level will help extend current knowledge on COPD pathogenesis and develop potential drugs.

METHODS

All lung tissues from non-smokers (n = 6), smokers without COPD (smokers, n = 7), and smokers with COPD (COPD, n = 7) were collected to detect messenger RNA (mRNA), microRNA (miRNA), circular RNA (circRNA), and long non-coding RNA (lncRNA) expression and identify the hub genes. Biological regulatory networks were constructed at the post-transcriptional level, including the RNA-binding protein (RBP)-hub gene interaction network and the competitive endogenous RNA (ceRNA) network. In addition, we assessed the composition and abundance of immune cells in COPD lung tissue and predicted potential therapeutic drugs for COPD. Finally, the hub genes were confirmed at both the RNA and protein levels.

RESULTS

Among the 20 participants, a total of 121169 mRNA transcripts, 1871 miRNA transcripts, 4244 circRNA transcripts, and 122130 lncRNA transcripts were detected. There were differences in the expression of 1561 mRNAs, 48 miRNAs, 33 circRNAs, and 545 lncRNAs between smokers and non-smokers, as well as 1289 mRNAs, 69 miRNAs, 32 circRNAs, and 433 lncRNAs between smokers and COPD patients. 18 hub genes were identified in COPD. TGF-β signaling and Wnt/β-catenin signaling may be involved in the development of COPD. Furthermore, the circRNA/lncRNA-miRNA-mRNA ceRNA networks and the RBP-hub gene interaction network were also constructed. Analysis of the immune cell infiltration level revealed that M2 macrophages and activated NK cells were increased in COPD lung tissues. Finally, we identified that the ITK inhibitor and oxybutynin chloride may be effective in treating COPD.

CONCLUSIONS

We identified several novel hub genes involved in COPD pathogenesis. TGF-β signaling and Wnt/β-catenin signaling were the most dysregulated pathways in COPD patients. Our study constructed post-transcriptional biological regulatory networks and predicted small-molecule drugs for the treatment of COPD, which enhanced the existing understanding of COPD pathogenesis and suggested an innovative direction for the therapeutic intervention of the disease.

Identification of non-small cell lung cancer with chronic obstructive pulmonary disease using clinical symptoms and routine examination: a retrospective study

Background

Patients with non-small cell lung cancer (NSCLC) and patients with NSCLC combined with chronic obstructive pulmonary disease (COPD) have similar physiological conditions in early stages, and the latter have shorter survival times and higher mortality rates. The purpose of this study was to develop and compare machine learning models to identify future diagnoses of COPD combined with NSCLC patients based on the patient's disease and routine clinical data.

Methods

Data were obtained from 237 patients with COPD combined with NSCLC as well as NSCLC admitted to Ningxia Hui Autonomous Region People's Hospital from October 2013 to July 2022. Six machine learning algorithms (K-nearest neighbor, logistic regression, eXtreme gradient boosting, support vector machine, naïve Bayes, and artificial neural network) were used to develop prediction models for NSCLC combined with COPD. Sensitivity, specificity, positive predictive value, negative predictive value, accuracy, F1 score, Mathews correlation coefficient (MCC), Kappa, area under the receiver operating characteristic curve (AUROC)and area under the precision-recall curve (AUPRC) were used as performance indicators to evaluate the performance of the models.

Results

135 patients with NSCLC combined with COPD, 102 patients with NSCLC were included in the study. The results showed that pulmonary function and emphysema were important risk factors and that the support vector machine-based identification model showed optimal performance with accuracy:0.946, recall:0.940, specificity:0.955, precision:0.972, npv:0.920, F1 score:0.954, MCC:0.893, Kappa:0.888, AUROC:0.975, AUPRC:0.987.

Conclusion

The use of machine learning tools combining clinical symptoms and routine examination data features is suitable for identifying the risk of concurrent NSCLC in COPD patients.

Quantifying emphysema in lung screening computed tomography with robust automated lobe segmentation

Purpose

Anatomy-based quantification of emphysema in a lung screening cohort has the potential to improve lung cancer risk stratification and risk communication. Segmenting lung lobes is an essential step in this analysis, but leading lobe segmentation algorithms have not been validated for lung screening computed tomography (CT).

Approach

In this work, we develop an automated approach to lobar emphysema quantification and study its association with lung cancer incidence. We combine self-supervised training with level set regularization and finetuning with radiologist annotations on three datasets to develop a lobe segmentation algorithm that is robust for lung screening CT. Using this algorithm, we extract quantitative CT measures for a cohort (n = 1189 ) from the National Lung Screening Trial and analyze the multivariate association with lung cancer incidence.

Results

Our lobe segmentation approach achieved an external validation Dice of 0.93, significantly outperforming a leading algorithm at 0.90 (p < 0.01 ). The percentage of low attenuation volume in the right upper lobe was associated with increased lung cancer incidence (odds ratio: 1.97; 95% CI: [1.06, 3.66]) independent of PLCO m 2012 risk factors and diagnosis of whole lung emphysema. Quantitative lobar emphysema improved the goodness-of-fit to lung cancer incidence (χ 2 = 7.48 , p = 0.02 ).

Conclusions

We are the first to develop and validate an automated lobe segmentation algorithm that is robust to smoking-related pathology. We discover a quantitative risk factor, lending further evidence that regional emphysema is independently associated with increased lung cancer incidence. The algorithm is provided at https://github.com/MASILab/EmphysemaSeg.

Lung Imaging in COPD Part 1: Clinical Usefulness

COPD is a condition characterized by chronic airflow obstruction resulting from chronic bronchitis, emphysema, or both. The clinical picture is usually progressive with respiratory symptoms such as exertional dyspnea and chronic cough. For many years, spirometry was used to establish a diagnosis of COPD. Recent advancements in imaging techniques allow quantitative and qualitative analysis of the lung parenchyma as well as related airways and vascular and extrapulmonary manifestations of COPD. These imaging methods may allow prognostication of disease and shed light on the efficacy of pharmacologic and nonpharmacologic interventions. This is the first of a two-part series of articles on the usefulness of imaging methods in COPD, and it highlights useful information that clinicians can obtain from these imaging studies to make more accurate diagnosis and therapeutic decisions.

Nomograms Using CT Morphological Features and Clinical Characteristics to Identify COPD in Patients with Lung Cancer: A Multicenter Study

Purpose

This study aimed to screen out computed tomography (CT) morphological features and clinical characteristics of patients with lung cancer to identify chronic obstructive pulmonary disease (COPD). Further, we aimed to develop and validate different diagnostic nomograms for predicting whether lung cancer is comorbid with COPD.

Patients and Methods

This retrospective study examined data from 498 patients with lung cancer (280 with COPD, 218 without COPD; 349 in training cohort, 149 in validation cohort) from two centers. Five clinical characteristics and 20 CT morphological features were evaluated. Differences in all variables were assessed between COPD and non-COPD groups. Models were developed using multivariable logistic regression to identify COPD, including clinical, imaging, and combined nomograms. Receiver operating characteristic curves were used to evaluate and compare the performance of nomograms.

Results

Age, sex, interface, bronchus cutoff sign, spine-like process, and spiculation sign were independent predictors of COPD in patients with lung cancer. In the training and validation cohorts, the clinical nomogram showed good performance to predict COPD in lung cancer patients (areas under the curves [AUCs] of 0.807 [95% CI, 0.761-0.854] and 0.753 [95% CI, 0.674-0.832]); while the imaging nomogram showed slightly better performance (AUCs of 0.814 [95% CI, 0.770-0.858] and 0.780 [95% CI, 0.705-0.856]). For the combined nomogram generated with clinical and imaging features, the performance was further improved (AUC=0.863 [95% CI, 0.824-0.903], 0.811 [95% CI, 0.742-0.880] in the training and validation cohort). At 60% risk threshold, there were more true negative predictions (48 vs 44) and higher accuracy (73.15% vs 71.14%) for the combined nomogram compared with the clinical nomogram in the validation cohort.

Conclusion

The combined nomogram developed with clinical and imaging features outperformed clinical and imaging nomograms; this provides a convenient method to detect COPD in patients with lung cancer using one-stop CT scanning.

Similar programmed death ligand 1 (PD-L1) expression profile in patients with mild COPD and lung cancer

Programmed Death Ligand 1 (PD-L1) is crucial in regulating the immunological tolerance in non-small cell lung cancer (NSCLC). Alveolar macrophage (AM)-derived PD-L1 binds to its receptor, PD-1, on surveilling lymphocytes, leading to lymphocyte exhaustion. Increased PD-L1 expression is associated with cigarette smoke (CS)-exposure. However, the PD-L1 role in CS-associated lung diseases associated with NSCLC, such as chronic obstructive pulmonary disease (COPD), is still unclear. In two different cohorts of ever smokers with COPD or NSCLC, and ever and never smoker controls, we evaluated PD-L1 expression: (1) via cutting-edge digital spatial proteomic and transcriptomic profiling (Geomx) of formalin-fixed paraffin-embedded (FFPE) lung tissue sections (n = 19); and (2) via triple immunofluorescence staining of bronchoalveolar lavage (BAL) AMs (n = 83). PD-L1 mRNA expression was also quantified in BAL AMs exposed to CS extract. PD-L1 expression was increased in the bronchiolar wall, parenchyma, and vascular wall from mild-moderate (GOLD 1-2) COPD patients compared to severe-very severe (GOLD 3-4) COPD patients and controls. Within all the COPD patients, PD-L1 protein expression was associated with upregulation of genes involved in tumor progression and downregulation of oncosuppressive genes, and strongly directly correlated with the FEV₁% predicted, indicating higher PD-L1 expression in the milder vs. more severe COPD stages. In bronchioles, PD-L1 levels were strongly directly correlated with the number of functionally active AMs. In BAL, we confirmed that AMs from patients with both GOLD 1-2 COPD and NSCLC had the highest and similar, PD-L1 expression levels versus all the other groups, independently from active cigarette smoking. Intriguingly, AMs from patients with more severe COPD had reduced AM PD-L1 expression compared to patients with mild COPD. Acute CS extract stimulation increased PD-L1 mRNA expression only in never-and not in ever-smoker AMs. Lungs from patients with mild COPD and NSCLC are characterized by a similar strong PD-L1 expression signature in bronchioles and functionally active AMs compared to patients with severe COPD and controls. Active smoking does not affect PD-L1 levels. These observations represent a new resource in understanding the innate immune mechanisms underlying the link between COPD and lung cancer onset and progression and pave the way to future studies focused on the mechanisms by which CS promotes tumorigenesis and COPD.

Chronic Obstructive Pulmonary Disease and Small Airways Diseases

The small airways are a common target of injury within the lungs and may be affected by a wide variety of inhaled, systemic, and other disorders. Imaging is critical in the detection and diagnosis of small airways disease since significant injury may occur prior to pulmonary function tests showing abnormalities. The goal of this article is to describe the typical imaging findings and patterns of small airways diseases. An approach which divides the imaging appearances into four categories (tree-in-bud opacities, poorly defined centrilobular nodules, mosaic attenuation, and emphysema) will provide a framework in which to formulate appropriate and focused differential diagnoses.

From COPD to Lung Cancer: Mechanisms Linking, Diagnosis, Treatment, and Prognosis

Many studies have proved that the pathogenesis of the chronic obstructive pulmonary disease (COPD) and lung cancer is related, and may cause and affect each other to a certain extent. In fact, the change of chronic airway obstruction will continue to have an impact on the screening, treatment, and prognosis of lung cancer.In this comprehensive review, we outlined the links and heterogeneity between COPD and lung cancer and finds that factors such as gene expression and genetic susceptibility, epigenetics, smoking, epithelial mesenchymal transformation (EMT), chronic inflammation, and oxidative stress injury may all play a role in the process. Although the relationship between these two diseases have been largely determined, the methods to prevent lung cancer in COPD patients are still limited. Early diagnosis is still the key to a better prognosis. Thus, it is necessary to establish more intuitive screening evaluation criteria and find suitable biomarkers for lung cancer screening in high-risk populations with COPD. Some studies have indicated that COPD may change the efficacy of anti-tumor therapy by affecting the response of lung cancer patients to immune checkpoint inhibitors (ICIs). And for lung cancer patients with COPD, the standardized management of COPD can improve the prognosis. The treatment of lung cancer patients with COPD is an individualized, comprehensive, and precise process. The development of new targets and new strategies of molecular targeted therapy may be the breakthrough for disease treatment in the future.

Prevalence of lung cancer in chronic obstructive pulmonary disease: A systematic review and meta-analysis

Background

There is growing evidence that chronic obstructive pulmonary disease (COPD) can increase the risk of lung cancer, which poses a serious threat to treatment and management. Therefore, we performed a meta-analysis of lung cancer prevalence in patients with COPD with the aim of providing better prevention and management strategies.

Methods

We systematically searched PubMed, EMBASE, Web of Science, and Cochrane Library databases from their inception to 20 March 2022 to collect studies on the prevalence of lung cancer in patients with COPD. We evaluated the methodological quality of the included studies using the tool for assessing the risk of bias in prevalence studies. Meta-analysis was used to determine the prevalence and risk factors for lung cancer in COPD. Subgroup and sensitivity analyses were conducted to explore the data heterogeneity. Funnel plots combined with Egger’s test were used to detect the publication biases.

Results

Thirty-one studies, covering 829,490 individuals, were included to investigate the prevalence of lung cancer in patients with COPD. Pooled analysis demonstrated that the prevalence of lung cancer in patients with COPD was 5.08% (95% confidence interval [CI]: 4.17–6.00%). Subgroup analysis showed that the prevalence was 5.09% (95% CI: 3.48–6.70%) in male and 2.52% (95% CI: 1.57–4.05%) in female. The prevalence of lung cancer in patients with COPD who were current and former smokers was as high as 8.98% (95% CI: 4.61–13.35%) and 3.42% (95% CI: 1.51–5.32%); the incidence rates in patients with moderate and severe COPD were 6.67% (95% CI: 3.20–10.14%) and 5.57% (95% CI: 1.89–16.39%), respectively, which were higher than the 3.89% (95% CI: 2.14–7.06%) estimated in patients with mild COPD. Among the types of lung cancer, adenocarcinoma and squamous cell carcinoma were the most common, with incidence rates of 1.59% (95% CI: 0.23–2.94%) and 1.35% (95% CI: 0.57–3.23%), respectively. There were also differences in regional distribution, with the highest prevalence in the Western Pacific region at 7.78% (95% CI: 5.06–10.5%), followed by the Americas at 3.25% (95% CI: 0.88–5.61%) and Europe at 3.21% (95% CI: 2.36–4.06%).

Conclusions

This meta-analysis shows that patients with COPD have a higher risk of developing lung cancer than those without COPD. More attention should be given to this result in order to reduce the risk of lung cancer in these patients with appropriate management and prevention.

Systematic review registration

International prospective register of systematic reviews, identifier CRD42022331872.

Fx-Net and PureNet: Convolutional Neural Network architecture for discrimination of Chronic Obstructive Pulmonary Disease from smokers and healthy subjects through electronic nose signals

As one of the most reliable and significant indicators, Chronic Obstructive Pulmonary Disease (COPD) becomes a robust predictor of lung cancer early detection, the world's leading cause of cancer death. One of the methods is to analyze the Volatile Organic Compounds (VOCs) in exhaled breath using electronic noses (E-noses), which have become emerging tools for analyzing breath because of their potential and promising technology for diagnosing. However, the signal processing of the E-Nose sensor becomes vital in exposing information about the subject condition, which most researchers strive to accomplish. We proposed a Convolutional Neural Network (CNN) architecture to classify COPD in smokers and non-smokers, healthy subjects, and smokers from E-Nose signals to contribute to this field. Two models were constructed following E-Nose signal processing state-of-the-arts. One was by combined feature extraction and classifier, and the second was by CNN, which directly processed the raw signal. In addition, various feature extraction and classifier (Machine Learning and CNN) used in prior research were investigated. Using 3K and 5K Fold cross-validation results demonstrated that our proposed models outperformed in Kernel Principal Component Analysis (KPCA) with Fx-ConvNet and Pure-ConvNet. They all reached maximum F1-Score with zero standard deviation values indicating a consistent result. Further experiments also showed that KPCA contributed to the increasing performance of some classifiers with average F1-Score 0.933 and 0.068 as standard deviation values.

Emphysema Progression at CT by Deep Learning Predicts Functional Impairment and Mortality: Results from the COPDGene Study

Background Visual assessment remains the standard for evaluating emphysema at CT; however, it is time consuming, is subjective, requires training, and is affected by variability that may limit sensitivity to longitudinal change. Purpose To evaluate the clinical and imaging significance of increasing emphysema severity as graded by a deep learning algorithm on sequential CT scans in cigarette smokers. Materials and Methods A secondary analysis of the prospective Genetic Epidemiology of Chronic Obstructive Pulmonary Disease (COPDGene) study participants was performed and included baseline and 5-year follow-up CT scans from 2007 to 2017. Emphysema was classified automatically according to the Fleischner emphysema grading system at baseline and 5-year follow-up using a deep learning model. Baseline and change in clinical and imaging parameters at 5-year follow-up were compared in participants whose emphysema progressed versus those who did not. Kaplan-Meier analysis and multivariable Cox regression were used to assess the relationship between emphysema score progression and mortality. Results A total of 5056 participants (mean age, 60 years ± 9 [SD]; 2566 men) were evaluated. At 5-year follow-up, 1293 of the 5056 participants (26%) had emphysema progression according to the Fleischner grading system. This group demonstrated progressive airflow obstruction (forced expiratory volume in 1 second [percent predicted]: -3.4 vs -1.8), a greater decline in 6-minute walk distance (-177 m vs -124 m), and greater progression in quantitative emphysema extent (adjusted lung density: -1.4 g/L vs 0.5 g/L; percentage of lung voxels with CT attenuation less than -950 HU: 0.6 vs 0.2) than those with nonprogressive emphysema (P < .001 for each). Multivariable Cox regression analysis showed a higher mortality rate in the group with emphysema progression, with an estimated hazard ratio of 1.5 (95% CI: 1.2, 1.8; P < .001). Conclusion An increase in Fleischner emphysema grade on sequential CT scans using an automated deep learning algorithm was associated with increased functional impairment and increased risk of mortality. ClinicalTrials.gov registration no. NCT00608764 © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Grenier in this issue.

Long-term outcome of chronic obstructive pulmonary disease: A review

Chronic obstructive pulmonary disease (COPD) is a chronic airway inflammation characterized by fixed airflow limitation and chronic respiratory symptoms, such as cough, sputum, and dyspnea. COPD is a progressive disease characterized by a decline in lung function. During the natural course of the disease, acute deterioration of symptoms leading to hospital visits can occur and influence further disease progression and subsequent exacerbation. Moreover, COPD is not only restricted to pulmonary manifestations but can present with other systemic diseases as comorbidities or systemic manifestations, including lung cancer, cardiovascular disease, pulmonary hypertension, sarcopenia, and metabolic abnormalities. These pulmonary and extrapulmonary conditions lead to the aggravation of dyspnea, physical inactivity, decreased exercise capacity, functional decline, reduced quality of life, and increased mortality. In addition, pneumonia, which is attributed to both COPD itself and an adverse effect of treatment (especially the use of inhaled and/or systemic steroids), can occur and lead to further deterioration in the prognosis of COPD. This review summarizes the long-term outcomes of patients with COPD. In addition, recent studies on the prediction of adverse outcomes are summarized in the last part of the review.

Down-regulation of transforming growth factor-beta and interleukin-6 serum levels in the idiopathic chronic obstructive pulmonary disease

BACKGROUND

Idiopathic chronic obstructive pulmonary disease (ICOPD) is a prevalent human disease. The etiology of the disease is yet to be clarified. The main aim of this project was to explore serum levels of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and transforming growth factor-beta (TGF-β) in the ICOPD patients in comparison to healthy controls.

METHODS

In this cross-sectional study, serum levels of IL-6, TNF-α and TGF-β were evaluated in the 70 non-smoker ICOPD patients and 70 sex and age matched controls, using ELISA technique by the commercial kits from Karmania Pars Gene Company. Analysis of data was performed by parametric independent and Pearson correlation test.

RESULTS

Serum levels of IL-6 and TGF-β, but not TNF-α, were significantly decreased in the ICOPD patients in comparison to controls. Serum levels of IL-6, TNF-α and TGF-β were not altered in the ICOPD male in comparison to female and also in mild when compared to moderate ICOPD patients.

CONCLUSIONS

Down-regulation of TGF-β may be the main risk factor for deterioration of inflammation in the ICOPD patients. Decreased IL-6 may be related to the idiopathic type of COPD.

Association between Chest CT-defined Emphysema and Lung Cancer: A Systematic Review and Meta-Analysis

Background Given the different methods of assessing emphysema, controversy exists as to whether it is associated with lung cancer. Purpose To perform a systematic review and meta-analysis of the association between chest CT-defined emphysema and the presence of lung cancer. Materials and Methods The PubMed, Embase, and Cochrane databases were searched up to July 15, 2021, to identify studies on the association between emphysema assessed visually or quantitatively with CT and lung cancer. Associations were determined by emphysema severity (trace, mild, or moderate to severe, assessed visually and quantitatively) and subtype (centrilobular and paraseptal, assessed visually). Overall and stratified pooled odds ratios (ORs) with their 95% CIs were obtained. Results Of the 3343 screened studies, 21 studies (107 082 patients) with 26 subsets were included. The overall pooled ORs for lung cancer given the presence of emphysema were 2.3 (95% CI: 2.0, 2.6; I² = 35%; 19 subsets) and 1.02 (95% CI: 1.01, 1.02; six subsets) per 1% increase in low attenuation area. Studies with visual (pooled OR, 2.3; 95% CI: 1.9, 2.6; I² = 48%; 12 subsets) and quantitative (pooled OR, 2.2; 95% CI: 1.8, 2.8; I² = 3.7%; eight subsets) assessments yielded comparable results for the dichotomous assessment. Based on six studies (1716 patients), the pooled ORs for lung cancer increased with emphysema severity and were higher for visual assessment (2.5, 3.7, and 4.5 for trace, mild, and moderate to severe, respectively) than for quantitative assessment (1.9, 2.2, and 2.5) based on point estimates. Compared with no emphysema, only centrilobular emphysema (three studies) was associated with lung cancer (pooled OR, 2.2; 95% CI: 1.5, 3.2; P < .001). Conclusion Both visual and quantitative CT assessments of emphysema were associated with a higher odds of lung cancer, which also increased with emphysema severity. Regarding subtype, only centrilobular emphysema was significantly associated with lung cancer. Clinical trial registration no. CRD42021262163 © RSNA, 2022 See also the editorial by Hunsaker in this issue. Online supplemental material is available for this article.

Computed Tomography Features of Lung Structure Have Utility for Differentiating Malignant and Benign Pulmonary Nodules

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a known comorbidity for lung cancer independent of smoking history. Quantitative computed tomography (qCT) imaging features related to COPD have shown promise in the assessment of lung cancer risk. We hypothesize that qCT features from the lung, lobe, and airway tree related to the location of the pulmonary nodule can be used to provide informative malignancy risk assessment.

METHODS

A total of 183 qCT features were extracted from 278 individuals with a solitary pulmonary nodule of known diagnosis (71 malignant, 207 benign). These included histogram and airway characteristics of the lungs, lobe, and segmental paths. Performances of the least absolute shrinkage and selection operator (LASSO) regression analysis and an ensemble of neural networks (ENN) were compared for feature set selection and classification on a testing cohort of 49 additional individuals (15 malignant, 34 benign).

RESULTS

The LASSO and ENN methods produced different feature sets for classification with LASSO selecting fewer qCT features (7) than the ENN (17). The LASSO model with the highest performing training area under the curve (AUC) (0.80) incorporated automatically extracted features and reader-measured nodule diameter with a testing AUC of 0.62. The ENN model with the highest performing AUC (0.77) also incorporated qCT and reader diameter but maintained higher testing performance AUC (0.79).

CONCLUSIONS

Automatically extracted qCT imaging features of the lung can be informative of the differentiation between individuals with malignant pulmonary nodules and those with benign pulmonary nodules, without requiring nodule segmentation and analysis.

[Study on the Benefit of Postoperative Exercise Rehabilitation in Patients with Lung Cancer Complicated with Chronic Obstructive Pulmonary Disease]

BACKGROUND

Chronic obstructive pulmonary diseases (COPD) affects 45%-63% of lung cancer patients worldwide. Lung cancer patients complicated with COPD have decreased cardiopulmonary function and increased perioperative risk, and their postoperative exercise endurance and lung function are significantly lower than those with conventional lung cancer. Previous studies have shown that postoperative exercise training can improve the exercise endurance of unselected lung cancer patients, but it is unclear whether lung cancer patients with COPD can also benefit from postoperative exercise training. This study intends to explore the effects of postoperative exercise training on exercise endurance, daily activity and lung function of lung cancer patients with COPD.

METHODS

Seventy-four patients with non-small cell lung cancer (NSCLC) complicated with COPD who underwent pneumonectomy in the lung cancer center of West China Hospital of Sichuan University from August 5, 2020 to August 25, 2021 were prospectively analyzed. They were randomly divided into exercise group and control group; The patients in the two groups received routine postoperative rehabilitation in the first week after operation, and the control group was given routine nursing from the second week. On this basis, the exercise group received postoperative exercise rehabilitation training for two weeks. Baseline evaluation was performed 3 days before operation and endpoint evaluation was performed 3 weeks after operation.

RESULTS

The exercise endurance, daily activity and pulmonary function test results of the two groups decreased from baseline to the end point. However, after the operation and intervention program, the maximum oxygen consumption of Cardiopulmonary Exercise Test and the walking distance of 6-Minute Walking Test in the exercise group were significantly better than those in the control group [(13.09±1.46) mL/kg/min vs (11.89±1.38) mL/kg/min, P=0.033; (297±46) m vs (243±43) m, P=0.041]. The average number of we-chat steps in the exercise group was also significantly better than that in the control group (4,381±397 vs 3,478±342, P=0.035). Forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) in the exercise group were better than those in the control group, but the difference did not reach a statistically significant level [(1.76±0.19) L vs (1.60±0.28) L, P=0.084; (1.01±0.17) L vs (0.96±0.21) L, P=0.467].

CONCLUSIONS

Postoperative exercise rehabilitation training can improve exercise endurance and daily activity ability of patients with lung cancer complicated with COPD and promote postoperative rehabilitation.

Prevalence and Newly Diagnosed Rates of Multimorbidity in Older Medicare Beneficiaries with COPD

Few studies have quantified the multimorbidity burden in older adults with chronic obstructive pulmonary disease (COPD) using large and generalizable data. Such evidence is essential to inform evidence-based research, clinical care, and resource allocation. This retrospective cohort study used a nationally representative sample of Medicare beneficiaries aged 65 years or older with COPD and 1:1 matched (on age, sex, and race) non-COPD beneficiaries to: (1) quantify the prevalence of multimorbidity at COPD onset and one-year later; (2) quantify the rates [per 100 person-years (PY)] of newly diagnosed multimorbidity during in the year prior to and in the year following COPD onset; and (3) compare multimorbidity prevalence in beneficiaries with and without COPD. Among 739,118 eligible beneficiaries with and without COPD, the average number of multimorbidity was 10.0 (SD = 4.7) and 1.0 (SD = 3.3), respectively. The most prevalent multimorbidity at COPD onset and at one-year after, respectively, were hypertension (70.8% and 80.2%), hyperlipidemia (52.2% and 64.8%), anemia (42.1% and 52.0%), arthritis (39.8% and 47.7%), and congestive heart failure (CHF) (31.3% and 38.8%). Conditions with the highest newly diagnosed rates before and following COPD onset, respectively, included hypertension (39.8 and 32.3 per 100 PY), hyperlipidemia (22.8 and 27.6), anemia (17.8 and 20.3), CHF (16.2 and 13.2), and arthritis (12.9 and 13.2). COPD was significantly associated with increased odds of all measured conditions relative to non-COPD controls. This study updates existing literature with more current, generalizable findings of the substantial multimorbidity burden in medically complex older adults with COPD-necessary to inform patient-centered, multidimensional care.Supplemental data for this article is available online at https://doi.org/10.1080/15412555.2021.1968815 .

Identification of Susceptible Genes for Chronic Obstructive Pulmonary Disease with Lung Adenocarcinoma by Weighted Gene Co-Expression Network Analysis

Purpose

Chronic obstructive pulmonary disease (COPD) and lung adenocarcinoma (LUAD) are common disorders and usually co-exists. However, genetic mechanisms between COPD and LUAD are rarely reported. This study aims to identify susceptible genes of COPD with LUAD.

Methods

Using the published data of GSE106899, co-expression modules were constructed by weighted gene co-expression network analysis (WGCNA). Subsequently, top 50 genes in the most tumor-related module were identified, among which hub genes were selected and validated.

Results

Twenty co-expression modules were constructed on 13,865 genes from 62 lung tissues of COPD patients with or without LUAD, in which one module (blue) was most related to tumorigenesis. Functional enrichment analyses showed that the genes in the blue module were mainly enriched in cell cycle, DNA transcription/replication and cancer pathways, etc. Combined with protein–protein interaction network, MTA1, PKMYT1 and FZR1 genes had the most intramodular connectivity, which were regarded as the hub genes. However, only FZR1 was validated to be overexpressed in lung tissues of COPD with LUAD and cigarette smoke extract-stimulated A549 cells, a human LUAD cell line.

Conclusion

This study suggests overexpression of FZR1 may play a key role in the tumorigenesis of LUAD in patients with COPD.

Emerging and multifaceted role of neutrophils in lung cancer

It has long been recognized that cigarette smoking is a shared risk factor for lung cancer and the debilitating lung disease, chronic obstructive pulmonary disease (COPD). As the severity of COPD increases, so does the risk for developing lung cancer, independently of pack years smoked. Neutrophilic inflammation increases with COPD severity and anti-inflammatories such as non-steroidal anti-inflammatory drugs (NSAIDs) can modulate neutrophil function and cancer risk. This review discusses the biology of tumour associated neutrophils (TANs) in lung cancer, which increase in density with tumour progression, particularly in smokers with non-small cell lung cancer (NSCLC). It is now increasingly recognized that neutrophils are responsive to the tumour microenvironment (TME) and polarize into distinct phenotypes that operate in an anti- (N1) or pro-tumorigenic (N2) manner. Intriguingly, the emergence of the pro-tumorigenic N2 phenotype increases with tumour growth, to suggest that cancer cells and the surrounding stroma can re-educate neutrophils. The neutrophil itself is a potent source of reactive oxygen species (ROS), arginase, proteases and cytokines that paradoxically can exert a potent immunosuppressive effect on lymphocytes including cytotoxic T cells (CTLs). Indeed, the neutrophil to lymphocyte ratio (NLR) is a systemic biomarker that is elevated in lung cancer patients and prognostic for poor survival outcomes. Herein, we review the molecular mechanisms by which neutrophil derived mediators can suppress CTL function. Selective therapeutic strategies designed to suppress pathogenic neutrophils in NSCLC may cooperate with immune checkpoint inhibitors (ICI) to increase CTL killing of cancer cells in the TME.

Exploring the impact of number and type of comorbidities on the risk of severe COPD exacerbations in Korean Population: a Nationwide Cohort Study

Background

It is difficult to assess the impact of multiple comorbidities on clinical outcomes in chronic obstructive pulmonary disease (COPD). In this study, we aimed to investigate exacerbation-associated comorbidities, determine whether the number of comorbidities is an independent risk factor for exacerbation, and identify other exacerbation-associated factors in a Korean COPD population using a nationwide population-based cohort. This study focused on severe exacerbations that required hospitalisation or emergency room visits.

Methods

The National Health Insurance Service-National Sample Cohort, version 2.0, data sampled between 2002 and 2015 were analysed. Data from two years after the diagnosis of COPD were analysed for each participant (N = 12,554, entire cohort). Moreover, 42% of the participants underwent additional health examinations (N = 5306, health-screening cohort). Fifteen comorbidities that were previously reported as risk factors for exacerbations were examined. A logistic regression model was used to analyse association with exacerbations.

Results

Asthma (1.57 [1.39–1.76] and 1.24 [1.06–1.44]), lung cancer (1.84 [1.30–2.59] and 2.28 [1.54–3.37]), and heart failure (1.39 [1.16–1.67] and 1.52 [1.18–1.97]) were associated with exacerbation in both cohorts (odds ratio [95% confidence interval] in the entire cohort and health-screening cohort, respectively). The number of comorbidities was an independent risk factor, and old age, male sex, low body mass index, and current smoking were also independent risk factors. High cholesterol levels and body mass index exerted protective effects against exacerbation.

Conclusions

The number of comorbidities, certain comorbidities such as asthma, lung cancer and heart failure, and low BMI were associated with an increased risk of severe exacerbation in COPD patients.

The radiologist's role in lung cancer screening

Lung cancer is still the deadliest cancer in men and women worldwide. This high mortality is related to diagnosis in advanced stages, when curative treatment is no longer an option. Large randomized controlled trials have shown that lung cancer screening (LCS) with low-dose computed tomography (CT) can detect lung cancers at earlier stages and reduce lung cancer-specific mortality. The recent publication of the significant reduction of cancer-related mortality by 26% in the Dutch-Belgian NELSON LCS trial has increased the likelihood that implementation of LCS in Europe will move forward. Radiologists are important stakeholders in numerous aspects of the LCS pathway. Their role goes beyond nodule detection and nodule management. Being part of a multidisciplinary team, radiologists are key players in numerous aspects of implementation of a high quality LCS program. In this non-systematic review we discuss the multifaceted role of radiologists in LCS.

How atmospheric pollutants impact the development of chronic obstructive pulmonary disease and lung cancer: A var-based model

The impact of air pollution on humans is a worrisome factor that has gained prominence over the years due to the importance of the topic to society. Lung cancer and chronic obstructive pulmonary disease are among the diseases associated with pollution that increase the mortality rate in Brazil and worldwide. Therefore, this study aimed to determine the impacts of air pollutants on mortality rates from chronic obstructive pulmonary disease (COPD) and lung cancer (LC) using vector autoregressive (VAR) modeling. The adjusted model was a VAR(1) and, according to the Granger causality test, the air pollutants selected were PM₁₀, O₃, CO, NO₂, and SO₂. The shocks applied to the variables O₃, using the impulse response function, negatively impacted COPD; in the eighth period, which is stabilized. The LC variable suffered more significant variations from O₃ and after a shock in this variable, an initially negative response in LC occurred and the series stabilized in period nine. After one year, 20.19% of COPD variance was explained by O₃. After twelve months, the atmospheric pollutant O₃ represented 5.00% and NO₂ represented 4.02% of LC variance. Moreover, the variables that caused the highest impact on COPD and LC mortality rates were O₃ and NO₂, indicating that air pollution influences the clinical state of people who have these diseases and even contributes to their development. The VAR model was able to identify the air pollutants that have the most significant impact on the diseases analyzed and explained the interrelationship between them.

Alkylating and oxidative stresses in smoking and non-smoking patients with COPD: Implications for lung carcinogenesis

Chronic obstructive pulmonary disease (COPD) is a disease characterized by chronic inflammation and irreversible airway obstruction. Cigarette smoking is the predominant risk factor for developing COPD. It is well-known that the COPD is also strongly associated with an increased risk of developing lung cancer. Cigarette smoke contains elevated concentrations of oxidants and various carcinogens (e.g., tobacco-derived nitrosamines) that can cause oxidative and alkylating stresses, which can also arise from inflammation. However, it is surprising that, except for oxidative stress, little information is available on the burden of alkylating stress and the detoxification efficiency of tobacco-derived carcinogens in COPD patients. In this study, we used LC-MS/MS to measure the archetypical tobacco-specific carcinogenic 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), its major metabolite, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), three biomarkers of oxidative stress (8-oxo-7,8-dihydroguanine, 8-oxoGua; 8-oxo-7,8-dihydro-2'-deoxyguanosine, 8-oxodGuo; 8-oxo-7,8-dihydroguanosine, 8-oxoGuo) and two biomarkers of alkylating stress (N7-methylguanine, N7-MeGua and N3-methyladenine, N3-MeAde), in the urine of smoking and non-smoking COPD patients and healthy controls. Our results showed that not only was oxidative stress significantly elevated in the COPD patients compared to the controls, but also alkylating stress. Significantly, levels of alkylating stress (i.e., N7-MeGua) were highly correlated with the COPD severity and not affected by age and smoking status. Furthermore, COPD smokers had significantly higher ratios of free NNAL to the total NNAL than control smokers, implying a lower detoxification efficiency of NNK in COPD smokers. This ratio was even higher in COPD smokers with stages 3-4 than in COPD smokers with stages 1-2. Taken together, our results demonstrated that the detoxification efficiency of tobacco-derived carcinogens (e.g., NNK) was associated with the pathogenesis and possibly the progression of COPD. In addition to oxidative stress, alkylating stress derived from chronic inflammation appears to be also dominant in COPD patients.

Predictors of Lung Cancer Risk: An Ecological Study Using Mortality and Environmental Data by Municipalities in Italy

Lung cancer (LC) mortality remains a consistent part of the total deaths occurring worldwide. Its etiology is complex as it involves multifactorial components. This work aims in providing an epidemiological assessment on occupational and environmental factors associated to LC risk by means of an ecological study involving the 8092 Italian municipalities for the period 2006-2015. We consider mortality data from mesothelioma as proxy of asbestos exposure, as well as PM2.5 and radon levels as a proxy of environmental origin. The compensated cases for occupational respiratory diseases, urbanization and deprivation were included as predictors. We used a negative binomial distribution for the response, with analysis stratified by gender. We estimated that asbestos is responsible for about 1.1% (95% CI: 0.8, 1.4) and 0.5% (95% CI: 0.2, 0.8) of LC mortality in males and females, respectively. The corresponding figures are 14.0% (95% CI: 12.5, 15.7) and 16.3% (95% CI: 16.2, 16.3) for PM2.5 exposure, and 3.9% (95% CI: 3.5, 4.2) and 1.6% (95% CI: 1.4, 1.7) for radon exposure. The assessment of determinants contribution to observed LC deaths is crucial for improving awareness of its origin, leading to increase the equity of the welfare system.

Quantification of Perinodular Emphysema in High-risk Patients Offers No Benefit in Lung Nodule Risk-Stratification of Malignancy Potential

PURPOSE

Pulmonary nodules, found either incidentally or on lung cancer screening, are common. Evaluating the benign or malignant nature of these nodules is costly in terms of patient risk and expense. The presence of both global and regional emphysema has been linked to increased lung cancer risk. We sought to determine whether the measurement of emphysema directly adjacent to a lung nodule could inform the likelihood of a nodule being malignant.

MATERIALS AND METHODS

Within a population of Veterans at high risk for lung cancer, 58 subjects with malignant nodules found on computerized tomographic chest scans were matched by lobe and nodule size to 58 controls. Lung densitometry was measured via determination of the low attenuation area percentage at -950 Hounsfield units (LAA950) and the Hounsfield unit (HU) value at which 15% of lung voxels have a lower lung density (Perc15), at predefined lung volumes that encompassed the nodule to evaluate both perinodular and regional lung fields. The association between measured lung density and malignancy was investigated using conditional logistic regression models, with densitometry measurements used as the primary predictor, adjusting for age alone, or age and computerized tomographic scan characteristics.

RESULTS

No significant differences in emphysema measurements between malignant and benign nodules were identified at lung volumes encompassing both perinodular and regional emphysema. Furthermore, emphysema quantification remained stable across lung volumes within individuals.

CONCLUSIONS

In this study, quantifying the degree of perinodular or regional emphysema did not offer any benefit in the risk stratification of lung nodules.

Quantitative Emphysema on Low-Dose CT Imaging of the Chest and Risk of Lung Cancer and Airflow Obstruction: An Analysis of the National Lung Screening Trial

BACKGROUND

Lung cancer risk prediction models do not routinely incorporate imaging metrics available on low-dose CT (LDCT) imaging of the chest ordered for lung cancer screening.

RESEARCH QUESTION

What is the association between quantitative emphysema measured on LDCT imaging and lung cancer incidence and mortality, all-cause mortality, and airflow obstruction in individuals who currently or formerly smoked and are undergoing lung cancer screening?

STUDY DESIGN AND METHODS

In 7,262 participants in the CT arm of the National Lung Screening Trial, percent low attenuation area (%LAA) was defined as the percentage of lung volume with voxels less than -950 Hounsfield units on the baseline examination. Multivariable Cox proportional hazards models, adjusting for competing risks where appropriate, were built to test for association between %LAA and lung cancer incidence, lung cancer mortality, and all-cause mortality with censoring at 6 years. In addition, multivariable logistic regression models were built to test the cross-sectional association between %LAA and airflow obstruction on spirometry, which was available in 2,700 participants.

RESULTS

The median %LAA was 0.8% (interquartile range, 0.2%-2.7%). Every 1% increase in %LAA was independently associated with higher hazards of lung cancer incidence (hazard ratio [HR], 1.02; 95% CI, 1.01-1.03; P = .004), lung cancer mortality (HR, 1.02; 95% CI, 1.00-1.05; P = .045), and all-cause mortality (HR, 1.01; 95% CI, 1.00-1.03; P = .042). Among participants with spirometry, 892 had airflow obstruction. The likelihood of airflow obstruction increased with every 1% increase in %LAA (odds ratio, 1.07; 95% CI, 1.06-1.09; P < .001). A %LAA cutoff of 1% had the best discriminative accuracy for airflow obstruction in participants aged > 65 years.

INTERPRETATION

Quantitative emphysema measured on LDCT imaging of the chest can be leveraged to improve lung cancer risk prediction and help diagnose COPD in individuals who currently or formerly smoked and are undergoing lung cancer screening.

Regional emphysema score is associated with tumor location and poor prognosis in completely resected NSCLC patients

BACKGROUND

Lung cancer is a frequent comorbidity of chronic obstructive pulmonary disease (COPD). However, the local risk of developing lung cancer related to regional emphysema distribution and clinical outcome has not been investigated. Our aim was to evaluate the impact of regional emphysema score (RES) on tumor location and prognosis in non-small cell lung cancer (NSCLC) patients.

METHODS

We enrolled 457 patients who underwent curative surgery for NSCLC at seven hospitals at The Catholic University of Korea from 2014 to 2018. Emphysema was visually assessed for each lobe, with the lingula as a separate lobe. Semi-quantitative emphysema scoring was classified as follows: 0 = none, 0.5 = 1 to 10%, 1 = 11 to 25%, 2 = 26 to 50%, 3 = 51 to 75%, and 4 = 76 to 100%. An RES was given to each of the six lung zone: the upper, middle, and lower lobes in the right and left lungs.

RESULTS

There were 145 patients in the high RES (≥ 3) group and 312 in the low RES (< 3) group. The mean RES in each lobe with cancer was significantly higher than that in other lobes without cancer (0.51 vs. 0.37, P <  0.001). This group showed significantly shorter disease-free survival (P <  0.001), in addition, presence of COPD, low diffusing capacity of the lung for carbon monoxide (< 80), smoking status, and poor differentiation were more frequent in this group. Also, cancer in a lobe with a higher RES (odds ratio (OR) = 1.56; 95% confidence interval (CI:1.01-2.42; P = 0.04), pathologic stage ≥ III (OR = 2.23; 95% CI: 1.28-3.89; P <  0.001), and poor differentiation (OR = 1.99; 95% CI: 1.22-3.21; P <  0.001) were independent factors for tumor recurrence.

CONCLUSIONS

The regional severity of emphysema by visual qualification was associated with the location of lung cancer, and was an independently poor prognostic factor for tumor recurrence in completely resected NSCLC patients.

Acute exacerbations of COPD and risk of lung cancer in COPD patients with and without a history of asthma

Rationale

There is limited knowledge on the effect of acute exacerbations in chronic obstructive pulmonary disease (AECOPD) on lung cancer risk in COPD patients with and without a history of asthma. This study aims to examine whether AECOPD is associated with risk of lung cancer, and whether the effect depends on a history of asthma.

Methods

In the GenKOLS study of 2003–2005, 852 subjects with COPD performed spirometry, and filled out questionnaires on smoking habits, symptoms and disease history. These data were linked to lung cancer data from the Cancer Registry of Norway through 2013. AECOPD, measured at baseline was the main predictor. To quantify differences in lung cancer risk, we performed Cox-proportional hazards regression. We adjusted for sex, age, smoking variables, body mass index, and lung function.

Measurements and results

During follow-up, 8.8% of the subjects with, and 5.9% of the subjects without exacerbations were diagnosed with lung cancer. Cox regression showed a significant increased risk of lung cancer with one or more exacerbations in COPD patients without a history of asthma, HRR = 2.77 (95% CI 1.39–5.52). We found a significant interaction between a history of asthma and AECOPD on lung cancer.

Conclusions

AECOPD is associated with an increased risk of lung cancer in COPD patients without a history of asthma.

Prevalence, Symptom Burden, and Underdiagnosis of Chronic Obstructive Pulmonary Disease in a Lung Cancer Screening Cohort

Rationale: Individuals eligible for lung cancer screening (LCS) by low-dose computed tomography (LDCT) are also at risk of chronic obstructive pulmonary disease (COPD) due to age and smoking exposure. Whether the LCS episode is useful for early detection of COPD is not well established.Objectives: To explore associations between symptoms, comorbidities, spirometry, and emphysema in participants enrolled in the Lung Screen Uptake Trial.Methods: This cross-sectional study was a prespecified analysis nested within Lung Screen Uptake Trial, which was a randomized study testing the impact of differing invitation materials on attendance of 60- to 75-year-old smokers and ex-smokers to a "lung health check" between November 2015 and July 2017. Participants with a smoking history ≥30 pack-years and who quit ≤15 years ago, or meeting a lung cancer risk of ≥1.51% via the Prostate Lung Colorectal Ovarian model or ≥2.5% via the Liverpool Lung Project model, were offered LDCT. COPD was defined and classified according to the GOLD (Global Initiative for Obstructive Lung Disease) criteria using prebronchodilator spirometry. Analyses included the use of descriptive statistics, chi-square tests to examine group differences, and univariable and multivariable logistic regression to explore associations between symptom prevalence, airflow limitation, and visually graded emphysema.Results: A total of 560 of 986 individuals included in the analysis (57%) had prebronchodilator spirometry consistent with COPD; 67% did not have a prior history of COPD and were termed "undiagnosed." Emphysema prevalence in those with known and "undiagnosed" COPD was 73% and 68%, respectively. A total of 32% of those with "undiagnosed COPD" had no emphysema on LDCT. Inhaler use and symptoms were more common in the "known" than the "undiagnosed" COPD group (63% vs. 33% with persistent cough [P < 0.001]; 73% vs. 33% with dyspnea [P < 0.001]). Comorbidities were common in all groups. Adjusted odds ratio (aOR) of respiratory symptoms were more significant for airflow obstruction (aOR GOLD 1 and 2, 1.57; confidence interval [CI], 1.14-2.17; aOR GOLD 3 and 4, 4.6; CI, 2.17-9.77) than emphysema (aOR mild, 1.12; CI, 0.81-1.55; aOR moderate, 1.33; CI, 0.85-2.09; aOR severe, 4.00; CI, 1.57-10.2).Conclusions: There is high burden of "undiagnosed COPD" and emphysema in LCS participants. Adding spirometry findings to the LDCT enhances identification of individuals with COPD.Clinical trial registered with www.clinicaltrials.gov (NCT02558101).

Recommendations for Implementing Lung Cancer Screening with Low-Dose Computed Tomography in Europe

Lung cancer screening (LCS) with low-dose computed tomography (LDCT) was demonstrated in the National Lung Screening Trial (NLST) to reduce mortality from the disease. European mortality data has recently become available from the Nelson randomised controlled trial, which confirmed lung cancer mortality reductions by 26% in men and 39-61% in women. Recent studies in Europe and the USA also showed positive results in screening workers exposed to asbestos. All European experts attending the "Initiative for European Lung Screening (IELS)"-a large international group of physicians and other experts concerned with lung cancer-agreed that LDCT-LCS should be implemented in Europe. However, the economic impact of LDCT-LCS and guidelines for its effective and safe implementation still need to be formulated. To this purpose, the IELS was asked to prepare recommendations to implement LCS and examine outstanding issues. A subgroup carried out a comprehensive literature review on LDCT-LCS and presented findings at a meeting held in Milan in November 2018. The present recommendations reflect that consensus was reached.

Recommendations for Implementing Lung Cancer Screening with Low-Dose Computed Tomography in Europe

Lung cancer screening (LCS) with low-dose computed tomography (LDCT) was demonstrated in the National Lung Screening Trial (NLST) to reduce mortality from the disease. European mortality data has recently become available from the Nelson randomised controlled trial, which confirmed lung cancer mortality reductions by 26% in men and 39-61% in women. Recent studies in Europe and the USA also showed positive results in screening workers exposed to asbestos. All European experts attending the "Initiative for European Lung Screening (IELS)"-a large international group of physicians and other experts concerned with lung cancer-agreed that LDCT-LCS should be implemented in Europe. However, the economic impact of LDCT-LCS and guidelines for its effective and safe implementation still need to be formulated. To this purpose, the IELS was asked to prepare recommendations to implement LCS and examine outstanding issues. A subgroup carried out a comprehensive literature review on LDCT-LCS and presented findings at a meeting held in Milan in November 2018. The present recommendations reflect that consensus was reached.

Nanomedicine in Non-Small Cell Lung Cancer: From Conventional Treatments to Immunotherapy

Non-small cell lung cancer (NSCLC) remains the most common cause of cancer-related mortality. The heterogeneous nature of this disease hinders its diagnosis and treatment, requiring continuous advances in research aiming to understand its intricate nature. Consequently, the retrospective analysis of conventional therapies has allowed the introduction of novel tools provided by nanotechnology, leading to considerable improvements in clinical outcomes. Furthermore, the development of novel immunotherapies based on the recently understood interaction of the immune system with the tumor highlights the real possibility of definitively treating NSCLC from its early stages. Novel engineering approaches in nanomedicine will enable to overcome the intrinsic limits of conventional and emerging therapies regarding off-site cytotoxicity, specificity, resistance mechanisms, and administration issues. The convergence point of these therapies with nanotechnology lays the foundation for achieving currently unmet needs.

Emphysema - The review of radiological presentation and its clinical impact in the LDCT screening era

Emphysema is one of three main lung pathologies in Chronic Obstructive Pulmonary Disease, along with chronic bronchitis and small airway obstruction. The diagnosis is based on detection of low attenuation areas in lung tissue on chest Computed Tomography, either visual by a radiologist, or automatic by the applied Computed Tomography software. Results of the studies on the association between emphysema and lung cancer incidence are mixed. Many studies have demonstrated, that chronic lung diseases, like Chronic Obstructive Pulmonary Disease, are associated with lung cancer morbidity. There is also evidence, that emphysema can be related with worse prognosis in patients with detected lung cancer. In this review article we aim to summarize current knowledge about emphysema detection and evaluation on Computed Tomography, both quantitative and qualitative. We also summarize current data on correlation between emphysema and lung cancer, as well as its potential use in selecting patients, who would most benefit from lung cancer screening.

Associations of county-level cumulative environmental quality with mortality of chronic obstructive pulmonary disease and mortality of tracheal, bronchus and lung cancers

Chronic obstructive pulmonary disease (COPD) and tracheal, bronchus, and lung (TBL) cancers are among the leading causes of mortality worldwide. Many environmental factors have been linked to COPD and TBL cancers. This study examined the associations of cumulative environmental quality indices with COPD mortality and TBL cancers mortality, respectively. Environmental Quality Index (EQI) was constructed to represent cumulative environmental quality for the overall environment and 5 major environmental domains (e.g., air, water, built). Associations of each EQI indices with COPD mortality and TBL cancers mortality, across 3109 counties in the 48 contiguous states of the US, were examined using simultaneous autoregressive (SAR) models. Stratified analyses were conducted in females versus males and according to rural-urban continuum codes (RUCC) to assess the heterogeneity across the overall population. Overall poor environmental quality was associated with a percent difference (PD) of 0.75 [95% confidence intervals (95% CI), 0.46, 1.05] in COPD mortality and an PD of 1.22 (95% CI, 0.97, 1.46) in TBL cancers mortality. PDs were higher in females than in males for both COPD and TBL cancers. The built domain had the largest effect on COPD mortality (PD, 0.85; 95% CI, 0.58, 1.12) while the air domain had the largest effect on TBL cancers mortality (PD, 1.54; 95% CI, 1.31, 1.76). The EQI-mortality associations varied among different RUCCs, but no consistent trend was found. This result suggests that poor environmental quality, particularly poor air quality and built environment quality may increase the mortality risk for COPD and that for TBL cancers. Females appear to be more susceptible to the effect of cumulative environmental quality. Our findings highlight the importance of improving overall and domain-specific cumulative environmental quality in reducing COPD and TBL cancer mortalities in the United States.

Deep Learning Enables Automatic Classification of Emphysema Pattern at CT

BackgroundPattern of emphysema at chest CT, scored visually by using the Fleischner Society system, is associated with physiologic impairment and mortality risk.PurposeTo determine whether participant-level emphysema pattern could predict impairment and mortality when classified by using a deep learning method.Materials and MethodsThis retrospective analysis of Genetic Epidemiology of COPD (COPDGene) study participants enrolled between 2007 and 2011 included those with baseline CT, visual emphysema scores, and survival data through 2018. Participants were partitioned into nonoverlapping sets of 2407 for algorithm training, 100 for validation and parameter tuning, and 7143 for testing. A deep learning algorithm using convolutional neural network and long short-term memory architectures was trained to classify pattern of emphysema according to Fleischner criteria. Deep learning scores were compared with visual scores and clinical parameters including pulmonary function tests. Cox proportional hazard models were used to evaluate relationships between emphysema scores and survival. The algorithm was also tested by using CT and clinical data in 1962 participants enrolled in the Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-points (ECLIPSE) study.ResultsA total of 7143 COPDGene participants (mean age ± standard deviation, 59.8 years ± 8.9; 3734 men and 3409 women) were evaluated. Deep learning emphysema classifications were associated with impaired pulmonary function tests, 6-minute walk distance, and St George's Respiratory Questionnaire at univariate analysis (P < .001 for each). Testing in the ECLIPSE cohort showed similar associations (P < .001). In the COPDGene test cohort, deep learning emphysema classification improved the fit of linear mixed models in the prediction of these clinical parameters compared with visual scoring (P < .001). Compared with participants without emphysema, mortality was greater in participants classified by the deep learning algorithm as having any grade of emphysema (adjusted hazard ratios were 1.5, 1.7, 2.9, 5.3, and 9.7, respectively, for trace, mild, moderate, confluent, and advanced destructive emphysema; P < .05).ConclusionDeep learning automation of the Fleischner grade of emphysema at chest CT is associated with clinical measures of pulmonary insufficiency and the risk of mortality.© RSNA, 2019Online supplemental material is available for this article.

Imaging Advances in Chronic Obstructive Pulmonary Disease. Insights from the Genetic Epidemiology of Chronic Obstructive Pulmonary Disease (COPDGene) Study

The Genetic Epidemiology of Chronic Obstructive Pulmonary Disease (COPDGene) study, which began in 2007, is an ongoing multicenter observational cohort study of more than 10,000 current and former smokers. The study is aimed at understanding the etiology, progression, and heterogeneity of chronic obstructive pulmonary disease (COPD). In addition to genetic analysis, the participants have been extensively characterized by clinical questionnaires, spirometry, volumetric inspiratory and expiratory computed tomography, and longitudinal follow-up, including follow-up computed tomography at 5 years after enrollment. The purpose of this state-of-the-art review is to summarize the major advances in our understanding of COPD resulting from the imaging findings in the COPDGene study. Imaging features that are associated with adverse clinical outcomes include early interstitial lung abnormalities, visual presence and pattern of emphysema, the ratio of pulmonary artery to ascending aortic diameter, quantitative evaluation of emphysema, airway wall thickness, and expiratory gas trapping. COPD is characterized by the early involvement of the small conducting airways, and the addition of expiratory scans has enabled measurement of small airway disease. Computational advances have enabled indirect measurement of nonemphysematous gas trapping. These metrics have provided insights into the pathogenesis and prognosis of COPD and have aided early identification of disease. Important quantifiable extrapulmonary findings include coronary artery calcification, cardiac morphology, intrathoracic and extrathoracic fat, and osteoporosis. Current active research includes identification of novel quantitative measures for emphysema and airway disease, evaluation of dose reduction techniques, and use of deep learning for phenotyping COPD.

Protein phosphatase 2A (PP2A): a key phosphatase in the progression of chronic obstructive pulmonary disease (COPD) to lung cancer

Lung cancer (LC) has the highest relative risk of development as a comorbidity of chronic obstructive pulmonary disease (COPD). The molecular mechanisms that mediate chronic inflammation and lung function impairment in COPD have been identified in LC. This suggests the two diseases are more linked than once thought. Emerging data in relation to a key phosphatase, protein phosphatase 2A (PP2A), and its regulatory role in inflammatory and tumour suppression in both disease settings suggests that it may be critical in the progression of COPD to LC. In this review, we uncover the importance of the functional and active PP2A holoenzyme in the context of both diseases. We describe PP2A inactivation via direct and indirect means and explore the actions of two key PP2A endogenous inhibitors, cancerous inhibitor of PP2A (CIP2A) and inhibitor 2 of PP2A (SET), and the role they play in COPD and LC. We explain how dysregulation of PP2A in COPD creates a favourable inflammatory micro-environment and promotes the initiation and progression of tumour pathogenesis. Finally, we highlight PP2A as a druggable target in the treatment of COPD and LC and demonstrate the potential of PP2A re-activation as a strategy to halt COPD disease progression to LC. Although further studies are required to elucidate if PP2A activity in COPD is a causal link for LC progression, studies focused on the potential of PP2A reactivating agents to reduce the risk of LC formation in COPD patients will be pivotal in improving clinical outcomes for both COPD and LC patients in the future.

Sequential screening for lung cancer in a high-risk group: randomised controlled trial: LungSEARCH: a randomised controlled trial of Surveillance using sputum and imaging for the EARly detection of lung Cancer in a High-risk group

BACKGROUND

Low-dose computed tomography (LDCT) screening detects early-stage lung cancer and reduces mortality. We proposed a sequential approach targeted to a high-risk group as a potentially efficient screening strategy.

METHODS

LungSEARCH was a national multicentre randomised trial. Current/ex-smokers with mild/moderate chronic obstructive pulmonary disease (COPD) were allocated (1:1) to have 5 years surveillance or not. Screened participants provided annual sputum samples for cytology and cytometry, and if abnormal were offered annual LDCT and autofluorescence bronchoscopy (AFB). Those with normal sputum provided annual samples. The primary end-point was the percentage of lung cancers diagnosed at stage I/II (nonsmall cell) or limited disease (small cell).

RESULTS

1568 participants were randomised during 2007-2011 from 10 UK centres. 85.2% of those screened provided an adequate baseline sputum sample. There were 42 lung cancers among 785 screened individuals and 36 lung cancers among 783 controls. 54.8% (23 out of 42) of screened individuals versus 45.2% (14 out of 31) of controls with known staging were diagnosed with early-stage disease (one-sided p=0.24). Relative risk was 1.21 (95% CI 0.75-1.95) or 0.82 (95% CI 0.52-1.31) for early-stage or advanced cancers, respectively. Overall sensitivity for sputum (in those randomised to surveillance) was low (40.5%) with a cumulative false-positive rate (FPR) of 32.8%. 55% of cancers had normal sputum results throughout. Among sputum-positive individuals who had AFB, sensitivity was 45.5% and cumulative FPR was 39.5%; the corresponding measures for those who had LDCT were 100% and 16.1%, respectively.

CONCLUSIONS

Our sequential strategy, using sputum cytology/cytometry to select high-risk individuals for AFB and LDCT, did not lead to a clear stage shift and did not improve the efficiency of lung cancer screening.

The importance of CT quantitative evaluation of emphysema in lung cancer screening cohort with negative findings by visual evaluation

INTRODUCTION

One-stop quantitative evaluation of emphysema and lung nodule in lung cancer screening is very important for patient.

OBJECTIVE

To evaluate the quantitative emphysema in the large-sample low-dose CT lung cancer screening cohort with negative CT findings by subjective visual assessment.

METHODS

One thousand, two hundred and thirty-one participants with negative visual evaluation were included in this retrospective study. The lungs were automatically segmented and the following were calculated: total lung volume (TLV), total emphysema volume (TEV), emphysema index (EI), 15th percentile lung density and mean lung density. EI ≥6% was defined as emphysema. The quantitative parameters were compared between different genders and ages. The quantitative parameters and risk factors were compared between emphysema and non-emphysema groups.

RESULTS

The proportion of smokers, TLV, TEV and EI of men were greater than that of women (P < 0.001). No correlation was found between age and volumes; the TEV and EI of people older than 60 years were greater than those younger than 60 years (P < 0.05) by age categorisation. One hundred and two participants showed emphysema, accounting for 8.29%. The incidence of emphysema in men was greater than that in women in total (P < 0.05). All the CT quantitative parameters were significantly different between emphysema and non-emphysema groups. The ratio of male, secondhand smoke exposure and chronic bronchitis history was greater in emphysema than that in the non-emphysema group (P < 0.05).

CONCLUSION

CT quantitative emphysema evaluation is recommended in people older than 60 years, especially in males, providing more precise information, aiding the early diagnosis of emphysema and informing early intervention.

The potential impact of chronic obstructive pulmonary disease in lung cancer screening: implications for the screening clinic

Introduction: Following the findings of the National Lung Screening Trial (NLST), lung cancer screening is now recommended in the United States. However, post-hoc analyses of the NLST suggest that reducing lung cancer mortality through screening is highly dependent on the underlying characteristics of the screening participants, in particular, the presence of chronic obstructive pulmonary disease (COPD). Areas covered: In this review, we outline how outcomes in lung cancer screening are significantly affected by the presence of airflow limitation, as caused by COPD, and how this might impact the assessment of eligible smokers in a lung cancer screening clinic. Expert opinion: There is growing evidence showing that CT-based screening for lung cancer reduces lung cancer mortality. The benefits of screening exceed those seen in the NLST when screening is carried out in lower risk populations, for a longer duration, and when outcomes are compared with usual care control cohorts. In this article, we review data from a post-hoc analysis of the NLST. We suggest that whilst worsened airflow limitation is associated with greater lung cancer risk, there is also more aggressive lung cancer, reduced lung cancer operability, and for advanced COPD, reduced benefits from screening. We advocate an 'outcomes-based' approach to screening over a 'risk-based' approach.