Chronic obstructive pulmonary disease and lung cancer incidence in never smokers: a cohort study

Associations between chronic obstructive pulmonary disease and ten common cancers: novel insights from Mendelian randomization analyses

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a significant global health issue, suspected to elevate the risk for various cancers. This study sought to discern whether COPD serves as a risk marker or a causative factor for prevalent cancers.

METHODS

We employed univariable MR (UVMR) analyses to investigate the causal relationship between COPD and the top ten common cancers. Sensitivity analyses were performed to validate the main findings. Multivariable MR (MVMR) and two-step MR analyses were also conducted. False-discovery-rate (FDR) was used to correct multiple testing bias.

RESULTS

The UVMR analysis demonstrated notable associations between COPD and lung cancer (odds ratio [OR] = 1.42, 95%CI 1.15-1.77, FDR = 6.37 × 10-3). This relationship extends to lung cancer subtypes such as squamous cell carcinoma (LUSC), adenocarcinoma (LUAD), and small cell lung cancer (SCLC). A tentative link was also identified between COPD and bladder cancer (OR = 1.53, 95%CI 1.03-2.28, FDR = 0.125). No significant associations were found between COPD and other types of cancer. The MVMR analysis that adjusted for smoking, alcohol drinking, and body mass index did not identify any significant causal relationships between COPD and either lung or bladder cancer. However, the two-step MR analysis indicates that COPD mediated 19.2% (95% CI 12.7-26.1%), 36.1% (24.9-33.2%), 35.9% (25.7-34.9%), and 35.5% (26.2-34.8%) of the association between smoking and overall lung cancer, as well as LUAD, LUSC, and SCLC, respectively.

CONCLUSIONS

COPD appears to act more as a risk marker than a direct cause of prevalent cancers. Importantly, it partially mediates the connection between smoking and lung cancer, underscoring its role in lung cancer prevention strategies.

MicroRNA Monitoring in Human Alveolar Macrophages from Patients with Smoking-Related Lung Diseases: A Preliminary Study

Chronic obstructive pulmonary disease (COPD) is a progressive lung disease that is commonly considered to be a potent driver of non-small cell lung cancer (NSCLC) development and related mortality. A growing body of evidence supports a role of the immune system, mainly played by alveolar macrophages (AMs), in key axes regulating the development of COPD or NSCLC phenotypes in response to harmful agents. MicroRNAs (miRNAs) are small non-coding RNAs that influence most biological processes and interfere with several regulatory pathways. The purpose of this study was to assess miRNA expression patterns in patients with COPD, NSCLC, and ever- or never-smoker controls to explore their involvement in smoking-related diseases. Bronchoalveolar lavage (BAL) specimens were collected from a prospective cohort of 43 sex-matched subjects to determine the expressions of hsa-miR-223-5p, 16-5p, 20a-5p, -17-5p, 34a-5p and 106a-5p by RT-PCR. In addition, a bioinformatic analysis of miRNA target genes linked to cancer was performed. Distinct and common miRNA expression levels were identified in each pathological group, suggesting their possible role as an index of NSCLC or COPD microenvironment. Moreover, we identified miRNA targets linked to carcinogenesis using in silico analysis. In conclusion, this study identified miRNA signatures in AMs, allowing us to understand the molecular mechanisms underlying smoking-related conditions and potentially providing new insights for diagnosis or pharmacological treatment.

Longitudinal BMI change and outcomes in Chronic Obstructive Pulmonary Disease: a nationwide population-based cohort study

BACKGROUND

The association between longitudinal body mass index (BMI) change and clinical outcomes in patients with chronic obstructive pulmonary disease (COPD) has not fully investigated.

METHODS

This retrospective cohort study included 116,463 COPD patients aged ≥ 40, with at least two health examinations, one within 2 years before and another within 3 years after COPD diagnosis (January 1, 2014, to December 31, 2019). Associations between BMI percentage change with all-cause mortality, primary endpoint, and initial severe exacerbation were assessed.

RESULTS

BMI decreased > 5% in 14,728 (12.6%), while maintained in 80,689 (69.2%), and increased > 5% in 21,046 (18.1%) after COPD diagnosis. Compared to maintenance group, adjusted hazard ratio (aHR) for all-cause mortality was 1.70 in BMI decrease group (95% CI:1.61, 1.79) and 1.13 in BMI increase group (95% CI:1.07, 1.20). In subgroup analysis, decrease in BMI showed a stronger effect on mortality as baseline BMI was lower, while an increase in BMI was related to an increase in mortality only in obese COPD patients with aHRs of 1.18 (95% CI: 1.03, 1.36). The aHRs for the risk of severe exacerbation (BMI decrease group and increase group vs. maintenance group) were 1.30 (95% CI:1.24, 1.35) and 1.12 (95% CI:1.07, 1.16), respectively.

CONCLUSIONS

A decrease in BMI was associated with an increased risk of all-cause mortality in a dose-dependent manner in patients with COPD. This was most significant in underweight patients. Regular monitoring for weight loss might be an important component for COPD management.

Impact of smoking reduction on lung cancer risk in patients with COPD who smoked fewer than 30 pack-years: a nationwide population-based cohort study

BACKGROUND

The effects of smoking reduction on the incidence of lung cancer in patients with chronic obstructive pulmonary disease (COPD) are not well known. This study aimed to investigate the effects of changes in smoking habits after COPD diagnosis on lung cancer development in patients who smoked less than 30 pack-years.

METHODS

This nationwide retrospective cohort study included 16,832 patients with COPD who smoked less than 30 pack-years at the time of COPD diagnosis. Based on changes in smoking habits in the health screening examination data, smokers were categorized into three groups: quitters, reducers, and sustainers. The primary outcome was the risk of lung cancer development, which was estimated using the Cox proportional hazards model. We also modelled the amount of smoking reduction as a continuous variable.

RESULTS

During a median follow-up of 4 years, the cumulative incidence of lung cancer was the highest among sustainers, followed by reducers and quitters. Compared with sustainers, reducers (adjusted HR 0.74, 95% CI:0.56-0.98) and quitters (adjusted HR 0.78, 95% CI:0.64-0.96) had a significantly lower risk of lung cancer. Incidence of lung cancer showed a decreasing trend with a decreasing amount of smoking (P for linearity < 0.01).

CONCLUSIONS

In patients with COPD who smoked less than 30 pack-years, smoking reduction and cessation lowered the risk of lung cancer.

Inflammation promotes aging-associated oncogenesis in the lung

Background

Lung cancer is the leading cause of cancer death in the world. While cigarette smoking is the major preventable factor for cancers in general and lung cancer in particular, old age is also a major risk factor. Aging-related chronic, low-level inflammation, termed inflammaging, has been widely documented; however, it remains unclear how inflammaging contributes to increased lung cancer incidence. Aim: To establish connections between aging-associated changes in the lungs and cancer risk.

Methods

We analyzed public databases of gene expression for normal and cancerous human lungs and used mouse models to understand which changes were dependent on inflammation, as well as to assess the impact on oncogenesis.

Results

Analyses of GTEx and TCGA databases comparing gene expression profiles from normal lungs, lung adenocarcinoma, lung squamous cell carcinoma of subjects across age groups revealed upregulated pathways such as inflammatory response, TNFA signaling via NFκB, and interferon-gamma response. Similar pathways were identified comparing the gene expression profiles of young and old mouse lungs. Transgenic expression of alpha 1 antitrypsin (AAT) partially reverses increases in markers of aging-associated inflammation and immune deregulation. Using an orthotopic model of lung cancer using cells derived from EML4-ALK fusion-induced adenomas, we demonstrated an increased tumor outgrowth in lungs of old mice while NLRP3 knockout in old mice decreased tumor volumes, suggesting that inflammation contributes to increased lung cancer development in aging organisms.

Conclusions

These studies reveal how expression of an anti-inflammatory mediator (AAT) can reduce some but not all aging-associated changes in mRNA and protein expression in the lungs. We further show that aging is associated with increased tumor outgrowth in the lungs, which may relate to an increased inflammatory microenvironment.

Evaluation of Risk Factors for Lung Cancer Among Never Smokers and Their Association With Common Driver Mutations

INTRODUCTION

The majority of lung cancers are caused by tobacco use, which is linked to lung tumors of all major histological types. A considerable fraction of lung cancer cases, the vast majority of which are adenocarcinomas, occur in "never smokers," who are characterized as having smoked fewer than 100 cigarettes in their lives. The primary objective was to assess risk factors for lung cancer in non-smokers. In contrast, secondary objectives included evaluating histological subtype, staging, and performance status and exploring associations between risk factors and common driver mutations.

MATERIAL AND METHODS

The study was a single-center, observational, case-control study done at All India Institute of Medical Science, Bhubaneswar, India that focused on non-smokers with lung cancer. It included 145 cases and 297 controls, with statistical analyses such as chi-square tests and logistic regression used to assess associations between risk factors and lung cancer, considering factors such as socioeconomic status, body mass index (BMI), occupation, outdoor and indoor air pollution, personal habits, and medical history.

RESULTS

The study, comprising 145 lung cancer cases in non-smokers and 297 controls, found that 92.4% (134/145) of cases had adenocarcinoma, 6.9% (10/145) had squamous cell carcinoma, and 0.7% (1/145) had small cell carcinoma. Significant associations were observed for high-risk occupations, indoor biomass use without proper ventilation, low BMI, and family history of lung cancer. Specific pre-existing lung conditions like old pulmonary tuberculosis and asthma were linked to increased and decreased odds of developing lung cancer, respectively. Environmental factors, living near heavy industry, and dietary habits showed significant associations. A significant association was not found between the driver mutations and the risk factors studied.

CONCLUSION

This single-center study sheds light on significant risk factors influencing lung cancer development among non-smokers. The predominant occurrence of adenocarcinoma and associations with high-risk occupations, indoor biomass exposure, low BMI, and family history emphasize the multifaceted nature of non-smoking-related lung cancer. The findings underscore the importance of comprehensive risk assessment and targeted preventive strategies in this population.

What are the risk factors for postoperative home oxygen therapy in patients with lung cancer?

Background

Home oxygen therapy (HOT) is used to treat chronic respiratory diseases and is sometimes required in patients with lung cancer after radical surgery. We aimed to identify the risk factors for postoperative home-based oxygen therapy in patients with lung cancer.

Methods

Patients who underwent surgery for primary lung cancer at Chiba University Hospital between January 2019 and March 2021 were included. Patients who did not undergo complete resection, died in hospital after surgery, or used oxygen therapy preoperatively were excluded. Eligible patients were divided into HOT and non-HOT groups. They were retrospectively analyzed for risk factors for postoperative HOT using medical records in a multivariate analysis.

Results

A total of 410 patients were included in this study, 24 (5.9%) of whom required HOT after surgery. The HOT group comprised significantly more men, heavy smokers, and patients with pulmonary comorbidities, low percent forced expiratory volume, percent forced vital capacity, predicted postoperative forced expiratory volume in 1 s, and postoperative pulmonary complications on univariate analysis. In a multivariate analysis, independent risk factors for postoperative HOT were pulmonary comorbidities [odds ratio (OR): 5.94; 95% confidence interval (CI): 1.64-21.5; P=0.002) and postoperative pulmonary complications (OR: 5.39; 95% CI: 2.14-13.5; P<0.001). The postoperative HOT application rate was calculated according to a formula developed for this purpose.

Conclusions

Comorbid pulmonary diseases and postoperative pulmonary complications were significantly associated with postoperative HOT in patients with lung cancer.

Machine learning model for circulating tumor DNA detection in chronic obstructive pulmonary disease patients with lung cancer

Background

Patients with chronic obstructive pulmonary disease (COPD) have a high risk of developing lung cancer. Due to the high rates of complications from invasive diagnostic procedures in this population, detecting circulating tumor DNA (ctDNA) as a non-invasive method might be useful. However, clinical characteristics that are predictive of ctDNA mutation detection remain incompletely understood. This study aimed to investigate factors associated with ctDNA detection in COPD patients with lung cancer.

Methods

Herein, 177 patients with COPD and lung cancer were prospectively recruited. Plasma ctDNA was genotyped using targeted deep sequencing. Comprehensive clinical variables were collected, including the emphysema index (EI), using chest computed tomography. Machine learning models were constructed to predict ctDNA detection.

Results

At least one ctDNA mutation was detected in 54 (30.5%) patients. After adjustment for potential confounders, tumor stage, C-reactive protein (CRP) level, and milder emphysema were independently associated with ctDNA detection. An increase of 1% in the EI was associated with a 7% decrease in the odds of ctDNA detection (adjusted odds ratio =0.933; 95% confidence interval: 0.857-0.999; P=0.047). Machine learning models composed of multiple clinical factors predicted individuals with ctDNA mutations at high performance (AUC =0.774).

Conclusions

ctDNA mutations were likely to be observed in COPD patients with lung cancer who had an advanced clinical stage, high CRP level, or milder emphysema. This was validated in machine learning models with high accuracy. Further prospective studies are required to validate the clinical utility of our findings.

Sex differences in chronic obstructive pulmonary disease characteristics: the Korea National Health and Nutrition Examination Survey 2007-2018

BACKGROUND/AIMS

Chronic obstructive pulmonary disease (COPD) is less prevalent in females than males, but it affects mortality in females. There may be sex differences in the clinical characteristics of COPD.

METHODS

We analyzed the Korea National Health and Nutrition Examination Survey dataset from 2007 to 2018. We compared the clinical characteristics and comorbidities in subjects with COPD according to sex. We adjusted the multivariate logistic regression of lung cancer prevalence according to COPD and sex by age and smoking amount.

RESULTS

Females with COPD tended to be older than males with COPD (64.1 ± 0.4 yr vs. 62.3 ± 0.2 yr, respectively, p < 0.001). Approximately 89% of males with COPD had a smoking history, while 86% of females with COPD were non-smokers (p < 0.001). Household income was lower (p < 0.001) and asthma and overall malignancy were more prevalent in females with COPD than males with COPD (25.5 vs. 11.6%, respectively, p < 0.001; (6.3 vs. 5.4%, respectively, p < 0.001). However, lung cancer was more common in males with COPD than females with COPD (0.9 vs. 0.1%, respectively, p < 0.001). Lung cancer prevalence increased in males with moderate COPD compared to subjects without COPD (OR, 4.409; 95% CI, 1.741-9.419).

CONCLUSION

Females with COPD had a lower smoking rate, household income, and lung cancer prevalence than males with COPD. More active COPD screening is needed for women of low socioeconomic status, even if they do not smoke.

Association Between Regular Moderate to Vigorous Physical Activity Initiation Following COPD Diagnosis and Mortality: An Emulated Target Trial Using Nationwide Cohort Data

BACKGROUND

Moderate to vigorous physical activity (MVPA) in patients with COPD affects their overall health outcomes, including symptom relief and improved quality of life. However, the magnitude of the effect of MVPA initiation on real-world clinical outcomes has not been well investigated.

RESEARCH QUESTION

How does MVPA initiation affect mortality and severe exacerbation in patients who have not engaged in MVPA prior to COPD diagnosis?

STUDY DESIGN AND METHODS

This study included patients with COPD aged ≥ 40 years who were not performing MVPA prior to COPD diagnosis and who had at least one health screening visit prior to and following their COPD diagnosis between January 1, 2010, and December 31, 2018. The main exposure was MVPA, defined as vigorous aerobic exercise > 20 min per day on ≥ 3 days per week or moderate aerobic exercise > 30 min per day on ≥ 5 days per week. The primary end point was all-cause mortality, and the secondary end point was initial severe exacerbation as the time to event following COPD diagnosis.

RESULTS

In total, 110,097 person-trials were included (27,564 MVPA increases and 82,533 control groups). No differences were observed between the covariates following matching. The adjusted hazards ratio of all-cause mortality for the MVPA group compared with the control group was 0.84 (95% CI, 0.79-0.89). In the subgroup analysis, patients aged > 65 years, female patients, those who had never smoked, and patients with a higher Charlson Comorbidity Index score displayed a stronger effect of MVPA on reducing mortality than younger male patients, those who had ever smoked, and patients with a lower Charlson Comorbidity Index score (Pinteraction < .05). The fully adjusted hazards ratio for the risk of severe exacerbation (MVPA group vs control) was 0.90 (95% CI, 0.87-0.94).

INTERPRETATION

Initiation of MVPA can potentially reduce mortality and severe exacerbations in patients with COPD, although personalized interventions and further clinical trials are necessary.

Clinical Characteristics and Outcomes in Hospitalized Patients with COVID-19 and Cancer History: A Multicenter Cross-Sectional Study in Southwestern Iran

Background: Cancer patients are more exposed to opportunistic infections, such as COVID-19, due to their poor health status. This study aimed to identify the clinical characteristics of cancer and non-cancer patients with COVID-19 that may lead to death, intubation, and ICU admission. Materials and Methods: A Multicenter Cross-Sectional study was conducted on confirmed COVID-19 adult patients with and without a history of cancer from March 2019 to March 2021. Demographic and clinical features, ICU admission, intubation, and discharge status have been extracted from patients' medical records. Chi-square, odds ratio, Mann-Whitney test, and logistic regression were used to analyze the data. Results: The death rate in 1332 cancer patients was 28% compared to the 91464 noncancer patients which was 9% with an odds ratio of 3.94 and p<0.001. ICU admission rates among the cancer group were 43%, while in the noncancer group, it was 17.9% (p<0.001). Moreover, intubation was done for 20.9% of cancer patients and 7.4% of non-cancer patients (p<0.001). However, no significant difference was observed between the two groups in terms of length of stay in the hospital. Multivariable logistic regression analysis showed that age, level of consciousness, SPO2, and autoimmune disorders were associated with mortality in cancer patients with COVID-19. Conclusion: This study showed that older age, loss of consciousness, low oxygen saturation, and suffering from autoimmune disorders were the predictors of death in cancer patients with COVID-19. These results can have important implications for the management and care of cancer patients with COVID-19.

Increased Lung Cancer Risk and Associated Risk Factors in Tuberculosis Survivors: A Korean Population-Based Study

BACKGROUND

Few studies have comprehensively evaluated the risk of lung cancer in tuberculosis survivors with consideration of smoking status and chronic obstructive pulmonary disease (COPD). Furthermore, little is known about lung cancer risk factors in tuberculosis survivors.

METHODS

This population-based cohort study enrolled tuberculosis survivors (n = 75 467) between 2010 and 2017 and 1:1 age- and sex-matched controls. Subjects were followed up for 1 year from the date of tuberculosis diagnosis to the date of the incident lung cancer, death, or December 2018, whichever came first. The risk of lung cancer was evaluated according to smoking and COPD status. We also evaluated the risk factors for lung cancer and developed an individualized lung cancer prediction model for tuberculosis survivors.

RESULTS

During a median follow-up duration of 4.8 years, the incident lung cancer risk was 1.72-fold higher in tuberculosis survivors than in the controls. Among tuberculosis survivors, those who were current smokers with ≥20 pack-years showed the highest risk of lung cancer (adjusted hazard ratio, 6.78) compared with never-smoker, non-tuberculosis-infected controls. tuberculosis survivors with COPD had a higher risk (2.43) than non-COPD, non-tuberculosis-infected controls. Risk factors for lung cancer in tuberculosis survivors were pulmonary tuberculosis, age >60 years, smoking, and the presence of COPD or asthma. The individualized lung cancer risk model showed good discrimination (concordance statistic = 0.827).

CONCLUSIONS

Previous tuberculosis infection is an independent risk factor regardless of smoking status or amount and COPD. Closer monitoring of tuberculosis survivors, especially heavy smokers or those with COPD, is needed for early lung cancer diagnosis.

Prevalence of pre-existing lung diseases and their association with income level among patients with lung cancer: a nationwide population-based case-control study in South Korea

BACKGROUND

This study aimed to estimate the prevalence of pre-existing lung diseases in patients with lung cancer compared to people without lung cancer and examine the association between income levels and pre-existing lung diseases.

METHODS

Data on patients with lung cancer (case) and the general population without lung cancer (non-cancer controls) matched by age, sex and region were obtained from the Korea National Health Insurance Service-National Health Information Database (n=51 586). Insurance premiums were divided into quintiles and medicaid patients. Conditional logistic regression models were used to examine the association between pre-existing lung diseases and the risk of lung cancer. The relationship between income level and the prevalence of pre-existing lung disease among patients with lung cancer was analysed using logistic regression models.

RESULTS

The prevalence of asthma (17.3%), chronic obstructive lung disease (COPD) (9.3%), pneumonia (9.1%) and pulmonary tuberculosis (1.6%) in patients with lung cancer were approximately 1.6-3.2 times higher compared with the general population without lung cancer. A significantly higher risk for lung cancer was observed in individuals with pre-existing lung diseases (asthma: OR=1.36, 95% CI 1.29 to 1.44; COPD: 2.11, 95% CI 1.94 to 2.31; pneumonia: 1.49, 95% CI 1.38 to 1.61; pulmonary tuberculosis: 2.16, 95% CI 1.75 to 2.66). Patients with lung cancer enrolled in medicaid exhibited higher odds of having pre-existing lung diseases compared with those in the top 20% income level (asthma: OR=1.75, 95% CI 1.56 to 1.96; COPD: 1.91, 95% CI 1.65 to 2.21; pneumonia: 1.73, 95% CI 1.50 to 2.01; pulmonary tuberculosis: 2.45, 95% CI 1.78 to 3.36).

CONCLUSIONS

Pre-existing lung diseases were substantially higher in patients with lung cancer than in the general population. The high prevalence odds of pre-existing lung diseases in medicaid patients suggests the health disparity arising from the lowest income group, underscoring a need for specialised lung cancer surveillance.

Prospective Detection of Early Lung Cancer in Patients With COPD in Regular Care by Electronic Nose Analysis of Exhaled Breath

BACKGROUND

Patients with COPD are at high risk of lung cancer developing, but no validated predictive biomarkers have been reported to identify these patients. Molecular profiling of exhaled breath by electronic nose (eNose) technology may qualify for early detection of lung cancer in patients with COPD.

RESEARCH QUESTION

Can eNose technology be used for prospective detection of early lung cancer in patients with COPD?

STUDY DESIGN AND METHODS

BreathCloud is a real-world multicenter prospective follow-up study using diagnostic and monitoring visits in day-to-day clinical care of patients with a standardized diagnosis of asthma, COPD, or lung cancer. Breath profiles were collected at inclusion in duplicate by a metal-oxide semiconductor eNose positioned at the rear end of a pneumotachograph (SpiroNose; Breathomix). All patients with COPD were managed according to standard clinical care, and the incidence of clinically diagnosed lung cancer was prospectively monitored for 2 years. Data analysis involved advanced signal processing, ambient air correction, and statistics based on principal component (PC) analysis, linear discriminant analysis, and receiver operating characteristic analysis.

RESULTS

Exhaled breath data from 682 patients with COPD and 211 patients with lung cancer were available. Thirty-seven patients with COPD (5.4%) demonstrated clinically manifest lung cancer within 2 years after inclusion. Principal components 1, 2, and 3 were significantly different between patients with COPD and those with lung cancer in both training and validation sets with areas under the receiver operating characteristic curve of 0.89 (95% CI, 0.83-0.95) and 0.86 (95% CI, 0.81-0.89). The same three PCs showed significant differences (P < .01) at baseline between patients with COPD who did and did not subsequently demonstrate lung cancer within 2 years, with a cross-validation value of 87% and an area under the receiver operating characteristic curve of 0.90 (95% CI, 0.84-0.95).

INTERPRETATION

Exhaled breath analysis by eNose identified patients with COPD in whom lung cancer became clinically manifest within 2 years after inclusion. These results show that eNose assessment may detect early stages of lung cancer in patients with COPD.

Effect of Broncho-Vaxom (OM-85) on the frequency of chronic obstructive pulmonary disease (COPD) exacerbations

BACKGROUND

Efforts have been made to reduce the risk of chronic obstructive pulmonary disease (COPD) exacerbations using a variety of measures. Broncho-Vaxom (BV) is an immunomodulating agent that has shown potential benefit by balancing between immune stimulation and regulation in patients with COPD. In this study, we evaluated the clinical efficacy of BV for reducing the risk of COPD exacerbations.

METHODS

This study was based on the Korean National Health Insurance database, which contains reimbursement information for almost the entire population of South Korea. We extracted data from 2016 to 2019 for patients started on BV during 2017-2018. We collected baseline data on demographics, comorbidities, inhaler use, hospital type, and insurance type 1 year before starting BV. We also analyzed exacerbation history, starting from the year before BV initiation.

RESULTS

In total, 238 patients were enrolled in this study. Their mean age was 69.2 ± 9.14 years, 79.8% were male, and 45% experienced at least one exacerbation. BV reduced the risk of moderate (odds ratio [OR] = 0.59, 95% confidence interval [CI]: 0.38-0.91) and moderate-to-severe exacerbations compared to pre- and post-BV (OR = 0.571, 95% CI: 0.37-0.89). BV use also reduced the incidence of moderate and moderate-to-severe exacerbations (incidence rate ratio [IRR] = 0.75, p = 0.03; and IRR = 0.77, p = 0.03, respectively). The use of BV was significantly delayed moderate exacerbations (hazard ratio = 0.68, p = 0.02), but not with moderate-to-severe or severe exacerbations.

CONCLUSION

The use of BV was associated with fewer moderate and moderate-to-severe exacerbations. Additionally, BV was associated with a delay in moderate COPD exacerbations.

International expert consensus on diagnosis and treatment of lung cancer complicated by chronic obstructive pulmonary disease

Background

Lung cancer combined by chronic obstructive pulmonary disease (LC-COPD) is a common comorbidity and their interaction with each other poses significant clinical challenges. However, there is a lack of well-established consensus on the diagnosis and treatment of LC-COPD.

Methods

A panel of experts, comprising specialists in oncology, respiratory medicine, radiology, interventional medicine, and thoracic surgery, was convened. The panel was presented with a comprehensive review of the current evidence pertaining to LC-COPD. After thorough discussions, the panel reached a consensus on 17 recommendations with over 70% agreement in voting to enhance the management of LC-COPD and optimize the care of these patients.

Results

The 17 statements focused on pathogenic mechanisms (n=2), general strategies (n=4), and clinical application in COPD (n=2) and lung cancer (n=9) were developed and modified. These statements provide guidance on early screening and treatment selection of LC-COPD, the interplay of lung cancer and COPD on treatment, and considerations during treatment. This consensus also emphasizes patient-centered and personalized treatment in the management of LC-COPD.

Conclusions

The consensus highlights the need for concurrent treatment for both lung cancer and COPD in LC-COPD patients, while being mindful of the mutual influence of the two conditions on treatment and monitoring for adverse reactions.

Trinity of inflammation, innate immune cells and cross-talk of signalling pathways in tumour microenvironment

Unresolved inflammation is a pathological consequence of persistent inflammatory stimulus and perturbation in regulatory mechanisms. It increases the risk of tumour development and orchestrates all stages of tumorigenesis in selected organs. In certain cancers, inflammatory processes create the appropriate conditions for neoplastic transformation. While in other types, oncogenic changes pave the way for an inflammatory microenvironment that leads to tumour development. Of interest, hallmarks of tumour-promoting and cancer-associated inflammation are striking similar, sharing a complex network of stromal (fibroblasts and vascular cells) and inflammatory immune cells that collectively form the tumour microenvironment (TME). The cross-talks of signalling pathways initially developed to support homeostasis, change their role, and promote atypical proliferation, survival, angiogenesis, and subversion of adaptive immunity in TME. These transcriptional and regulatory pathways invariably contribute to cancer-promoting inflammation in chronic inflammatory disorders and foster "smouldering" inflammation in the microenvironment of various tumour types. Besides identifying common target sites of numerous cancer types, signalling programs and their cross-talks governing immune cells' plasticity and functional diversity can be used to develop new fate-mapping and lineage-tracing mechanisms. Here, we review the vital molecular mechanisms and pathways that establish the connection between inflammation and tumour development, progression, and metastasis. We also discussed the cross-talks between signalling pathways and devised strategies focusing on these interaction mechanisms to harness synthetic lethal drug combinations for targeted cancer therapy.

The Lung Microbiome in COPD and Lung Cancer: Exploring the Potential of Metal-Based Drugs

Chronic obstructive pulmonary disease (COPD) and lung cancer 17 are two of the most prevalent and debilitating respiratory diseases worldwide, both associated with high morbidity and mortality rates. As major global health concerns, they impose a substantial burden on patients, healthcare systems, and society at large. Despite their distinct aetiologies, lung cancer and COPD share common risk factors, clinical features, and pathological pathways, which have spurred increasing research interest in their co-occurrence. One area of particular interest is the role of the lung microbiome in the development and progression of these diseases, including the transition from COPD to lung cancer. Exploring novel therapeutic strategies, such as metal-based drugs, offers a potential avenue for targeting the microbiome in these diseases to improve patient outcomes. This review aims to provide an overview of the current understanding of the lung microbiome, with a particular emphasis on COPD and lung cancer, and to discuss the potential of metal-based drugs as a therapeutic strategy for these conditions, specifically concerning targeting the microbiome.

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.

Multi-morbidity and its association with common cancer diagnoses: a UK Biobank prospective study

BACKGROUND

Whilst multi-morbidity is known to be a concern in people with cancer, very little is known about the risk of cancer in multi-morbid patients. This study aims to investigate the risk of being diagnosed with lung, colorectal, breast and prostate cancer associated with multi-morbidity.

METHODS

We investigated the association between multi-morbidity and subsequent risk of cancer diagnosis in UK Biobank. Cox models were used to estimate the relative risks of each cancer of interest in multi-morbid participants, using the Cambridge Multimorbidity Score. The extent to which reverse causation, residual confounding and ascertainment bias may have impacted on the findings was robustly investigated.

RESULTS

Of the 436,990 participants included in the study who were cancer-free at baseline, 21.6% (99,965) were multi-morbid (≥ 2 diseases). Over a median follow-up time of 10.9 [IQR 10.0-11.7] years, 9,019 prostate, 7,994 breast, 5,241 colorectal, and 3,591 lung cancers were diagnosed. After exclusion of the first year of follow-up, there was no clear association between multi-morbidity and risk of colorectal, prostate or breast cancer diagnosis. Those with ≥ 4 diseases at recruitment had double the risk of a subsequent lung cancer diagnosis compared to those with no diseases (HR 2.00 [95% CI 1.70-2.35] p for trend < 0.001). These findings were robust to sensitivity analyses aimed at reducing the impact of reverse causation, residual confounding from known cancer risk factors and ascertainment bias.

CONCLUSIONS

Individuals with multi-morbidity are at an increased risk of lung cancer diagnosis. While this association did not appear to be due to common sources of bias in observational studies, further research is needed to understand what underlies this association.

Association between COPD and Stage of Lung Cancer Diagnosis: A Population-Based Study

Chronic obstructive pulmonary disease (COPD) is associated with an increased risk of lung cancer; however, the association between COPD and stage of lung cancer diagnosis is unclear. We conducted a population-based cross-sectional analysis of lung cancer patients (2008-2020) in Ontario, Canada. Using estimated propensity scores and inverse probability weighting, logistic regression models were developed to assess the association between COPD and lung cancer stage at diagnosis (early: I/II, advanced: III/IV), accounting for prior chest imaging. We further examined associations in subgroups with previously diagnosed and undiagnosed COPD. Over half (55%) of all lung cancer patients in Ontario had coexisting COPD (previously diagnosed: 45%, undiagnosed at time of cancer diagnosis: 10%). Compared to people without COPD, people with COPD had 30% lower odds of being diagnosed with lung cancer in the advanced stages (OR = 0.70, 95% CI: 0.68 to 0.72). Prior chest imaging only slightly attenuated this association (OR = 0.77, 95% CI: 0.75 to 0.80). The association with lower odds of advanced-stage diagnosis remained, regardless of whether COPD was previously diagnosed (OR = 0.68, 95% CI: 0.66 to 0.70) or undiagnosed (OR = 0.77, 95% CI: 0.73 to 0.82). Although most lung cancers are detected in the advanced stages, underlying COPD was associated with early-stage detection. Lung cancer diagnostics may benefit from enhanced partnership with COPD healthcare providers.

Enhanced Lyn Activity Causes Severe, Progressive Emphysema and Lung Cancer

The epidemiological patterns of incident chronic obstructive pulmonary disease (COPD) and lung adenocarcinoma are changing, with an increasing fraction of disease occurring in patients who are never-smokers or were not exposed to traditional risk factors. However, causative mechanism(s) are obscure. Overactivity of Src family kinases (SFKs) and myeloid cell-dependent inflammatory lung epithelial and endothelial damage are independent candidate mechanisms, but their pathogenic convergence has not been demonstrated. Here we present a novel preclinical model in which an activating mutation in Lyn, a nonreceptor SFK that is expressed in immune cells, epithelium, and endothelium-all strongly implicated in the pathogenesis of COPD-causes spontaneous inflammation, early-onset progressive emphysema, and lung adenocarcinoma. Surprisingly, even though activated macrophages, elastolytic enzymes, and proinflammatory cytokines were prominent, bone marrow chimeras formally demonstrated that myeloid cells were not disease initiators. Rather, lung disease arose from aberrant epithelial cell proliferation and differentiation, microvascular lesions within an activated endothelial microcirculation, and amplified EGFR (epidermal growth factor receptor) expression. In human bioinformatics analyses, LYN expression was increased in patients with COPD and was correlated with increased EGFR expression, a known lung oncogenic pathway, and LYN was linked to COPD. Our study shows that a singular molecular defect causes a spontaneous COPD-like immunopathology and lung adenocarcinoma. Furthermore, we identify Lyn and, by implication, its associated signaling pathways as new therapeutic targets for COPD and cancer. Moreover, our work may inform the development of molecular risk screening and intervention methods for disease susceptibility, progression, and prevention of these increasingly prevalent conditions.

Chronic obstructive pulmonary disease alters the genetic landscape and tumor immune microenvironment in lung cancer patients

Background

Chronic obstructive pulmonary disease (COPD) and lung cancer are leading causes of morbidity and mortality worldwide. Studies have reported molecular alterations in patients with lung cancer and in patients with COPD. However, few investigation has been conducted on the molecular characteristics of lung cancer patients with COPD.

Materials and methods

We performed a retrospective cohort study that included 435 patients with pathologically confirmed lung cancer at the Ruijin Hospital. For patients with documented spirometry, Global Initiative for Chronic Obstructive Lung Disease criteria were used to define COPD. For patients without documented spirometry, chest computed tomography and other clinical information were used to define COPD. Tumor tissue DNA was extracted from formalin-fixed paraffin-embedded samples. DNA mutation analysis, multiplex immunohistochemistry (mIHC), calculation of tumor mutational burden (TMB), mutant-allele tumor heterogeneity (MATH), and predication of neoantigens were performed.

Results

Although SNV mutations in lung cancer patients with COPD (G1 group) were generally higher than those in lung cancer patients without COPD (G2 group), the difference in the number of mutations was insignificant between the two groups. Of the 35 mutated genes, the number of them was higher in G1 than in G2, except that of EGFR. PI3K-Akt signaling pathway was enriched from significantly different genes. While TMB and MATH levels were not significantly different, the tumor neoantigen burdenwas markedly higher in G1 than that in G2. The level of CD68+ macrophages was significant higher in the stroma and total areas in the G1 group than in G2 group. The level of CD8+ lymphocytes was markedly higher in the stroma and showed a clear tendency forhigher expression in the G1 group than inthe G2 group. No significant differences were observed for the level of programmed death-ligand 1+ (PD-L1+), programmed death 1+ (PD-1+), and CD68PD-L1 in the stroma, tumor and total areas.

Conclusion

Our study revealed different genetic aberrations and pathways, higher neoantigen burden, and higher level of CD68+ macrophages and CD8+ T lymphocytes in lung cancer patients with COPD. Our investigation implies that the existence of COPD should be considered and immunotherapy is a potential choice when treating lung cancer patients with COPD.

Air pollution and mortality in patients with chronic obstructive pulmonary disease: a cohort study in South Korea

Background

Evidence on whether long-term exposure to air pollution increases the mortality risk in patients with chronic obstructive pulmonary disease (COPD) is limited.

Objectives

We aimed to investigate the associations of long-term exposure to particulate matter with diameter <10 µm (PM10) and nitrogen dioxide (NO2) with overall and disease-specific mortality in COPD patients.

Design

We conducted a nationwide retrospective cohort study of 121,423 adults ⩾40 years diagnosed with COPD during 1 January to 31 December 2009.

Methods

Exposure to PM10 and NO2 was estimated for residential location using the ordinary kriging method. We estimated the risk of overall mortality associated with 1-, 3-, and 5-years average concentrations of PM10 and NO2 using Cox proportional hazards models and disease-specific mortality using the Fine and Gray method adjusted for age, sex, income, body mass index, smoking, comorbidities, and exacerbation history.

Results

The adjusted hazard ratios (HRs) for overall mortality associated with a 10 µg/m3 increase in 1-year PM10 and NO2 exposures were 1.004 [95% confidence interval (CI) = 0.985, 1.023] and 0.993 (95% CI = 0.984, 1.002), respectively. The results were similar for 3- and 5-year exposures. For a 10-µg/m3 increase in 1-year PM10 and NO2 exposures, the adjusted HRs for chronic lower airway disease mortality were 1.068 (95% CI = 1.024, 1.113) and 1.029 (95% CI = 1.009, 1.050), respectively. In stratified analyses, exposures to PM10 and NO2 were associated with overall mortality in patients who were underweight and had a history of severe exacerbation.

Conclusion

In this large population-based study of patients with COPD, long-term PM10 and NO2 exposures were not associated with overall mortality but were associated with chronic lower airway disease mortality. PM10 and NO2 exposures were both associated with an increased risk of overall mortality, and with overall mortality in underweight individuals and those with a history of severe exacerbation.

Detection and size quantification of pulmonary nodules in ultralow-dose versus regular-dose CT: a comparative study in COPD patients

OBJECTIVE

To evaluate detectability and semi-automatic diameter and volume measurements of pulmonary nodules in ultralow-dose CT (ULDCT) vs regular-dose CT (RDCT).

METHODS

Fifty patients with chronic obstructive pulmonary disease (COPD) underwent RDCT on 64-multidetector CT (120 kV, filtered back projection), and ULDCT on third-generation dual source CT (100 kV with tin filter, advanced modeled iterative reconstruction). One radiologist evaluated the presence of nodules on both scans in random order, with discrepancies judged by two independent radiologists and consensus reading. Sensitivity of nodule detection on RDCT and ULDCT was compared to reader consensus. Systematic error in semi-automatically derived diameter and volume, and 95% limits of agreement (LoA) were evaluated. Nodule classification was compared by κ statistics.

RESULTS

ULDCT resulted in 83.1% (95% CI: 81.0-85.2) dose reduction compared to RDCT (p < 0.001). 45 nodules were present, with diameter range 4.0-25.3 mm and volume range 16.0-4483.0 mm³. Detection sensitivity was non-significant (p = 0.503) between RDCT 88.8% (95% CI: 76.0-96.3) and ULDCT 95.5% (95% CI: 84.9-99.5). No systematic bias in diameter measurements (median difference: -0.2 mm) or volumetry (median difference: -6 mm³) was found for ULDCT compared to RDCT. The 95% LoA for diameter and volume measurements were ±3.0 mm and ±33.5%, respectively. κ value for nodule classification was 0.852 for diameter measurements and 0.930 for volumetry.

CONCLUSION

ULDCT based on Sn100 kV enables comparable detectability of solid pulmonary nodules in COPD patients, at 83% reduced radiation dose compared to RDCT, without relevant difference in nodule measurement and size classification.

ADVANCES IN KNOWLEDGE

Pulmonary nodule detectability and measurements in ULDCT are comparable to RDCT.

Lung microRNAs Expression in Lung Cancer and COPD: A Preliminary Study

Non-small cell lung cancer (NSCLC) is one of the deadliest diseases worldwide and represents an impending burden on the healthcare system. Despite increasing attention, the mechanisms underlying tumorigenesis in cancer-related diseases such as COPD remain unclear, making novel biomarkers necessary to improve lung cancer early diagnosis. MicroRNAs (miRNAs) are short non-coding RNA that interfere with several pathways and can act as oncogenes or tumor suppressors. This study aimed to compare miRNA lung expression between subjects with NSCLC and COPD and healthy controls to obtain the miRNA expression profile by analyzing shared pathways. Lung specimens were collected from a prospective cohort of 21 sex-matched subjects to determine the tissue miRNA expression of hsa-miR-34a-5p, 33a-5p, 149-3p, 197-3p, 199-5p, and 320a-3p by RT-PCR. In addition, an in silico prediction of miRNA target genes linked to cancer was performed. We found a specific trend for has-miR-149-3p, 197-3p, and 34a-5p in NSCLC, suggesting their possible role as an index of the tumor microenvironment. Moreover, we identified novel miRNA targets, such as the Cyclin-Dependent Kinase (CDK) family, linked to carcinogenesis by in silico analysis. In conclusion. this study identified lung miRNA signatures related to the tumorigenic microenvironment, suggesting their possible role in improving the evaluation of lung cancer onset.

Do Patients with Bronchiectasis Have an Increased Risk of Developing Lung Cancer? A Systematic Review

BACKGROUND

Initial evidence supports the hypothesis that patients with non-cystic fibrosis bronchiectasis (NCFB) have a higher risk of lung cancer. We systematically reviewed the available literature to define the characteristics of lung malignancies in patients with bronchiectasis and the characteristics of patients who develop bronchiectasis-associated lung cancer.

METHOD

This study was performed based on the PRISMA guidelines. The review protocol was registered in PROSPERO.

RESULTS

The frequency rates of lung cancer in patients with NCFB ranged from 0.93% to 8.0%. The incidence rate was 3.96. Cancer more frequently occurred in the elderly and males. Three studies found an overall higher risk of developing lung cancer in the NCFB population compared to the non-bronchiectasis one, and adenocarcinoma was the most frequently reported histological type. The effect of the co-existence of NCFB and COPD was unclear.

CONCLUSIONS

NCFB is associated with a higher risk of developing lung cancer than individuals without NCFB. This risk is higher for males, the elderly, and smokers, whereas concomitant COPD's effect is unclear.

Mechanisms Contributing to the Comorbidity of COPD and Lung Cancer

Lung cancer and chronic obstructive pulmonary disease (COPD) often co-occur, and individuals with COPD are at a higher risk of developing lung cancer. While the underlying mechanism for this risk is not well understood, its major contributing factors have been proposed to include genomic, immune, and microenvironment dysregulation. Here, we review the evidence and significant studies that explore the mechanisms underlying the heightened lung cancer risk in people with COPD. Genetic and epigenetic changes, as well as the aberrant expression of non-coding RNAs, predispose the lung epithelium to carcinogenesis by altering the expression of cancer- and immune-related genes. Oxidative stress generated by tobacco smoking plays a role in reducing genomic integrity, promoting epithelial-mesenchymal-transition, and generating a chronic inflammatory environment. This leads to abnormal immune responses that promote cancer development, though not all smokers develop lung cancer. Sex differences in the metabolism of tobacco smoke predispose females to developing COPD and accumulating damage from oxidative stress that poses a risk for the development of lung cancer. Dysregulation of the lung microenvironment and microbiome contributes to chronic inflammation, which is observed in COPD and known to facilitate cancer initiation in various tumor types. Further, there is a need to better characterize and identify the proportion of individuals with COPD who are at a high risk for developing lung cancer. We evaluate possible novel and individualized screening strategies, including biomarkers identified in genetic studies and exhaled breath condensate analysis. We also discuss the use of corticosteroids and statins as chemopreventive agents to prevent lung cancer. It is crucial that we optimize the current methods for the early detection and management of lung cancer and COPD in order to improve the health outcomes for a large affected population.

All-cause admissions following a first ever exacerbation-related hospitalisation in COPD

Background

Hospital admissions are important contributors to the overall burden of chronic obstructive pulmonary disease (COPD). Understanding the patterns and causes of hospital admissions will help to identify targets for preventive interventions. This study aimed to determine the 5-year all-cause hospital admission trajectories of patients with COPD following their first ever exacerbation-related hospitalisation.

Methods

Patients with COPD were identified from the Danish national registries. Patients experiencing their first ever exacerbation-related hospitalisation, defined as the index event, between 2000 and 2014 were included. All-cause hospital admissions were examined during a subsequent 5-year follow-up period, and categorised using the International Classification of Diseases, 10th revision.

Results

In total, 82 964 patients with COPD were included. The mean±sd age was 72±10 years and 48% were male. Comorbidities were present in 58%, and 65% of the patients collected inhalation medication ≤6 months prior to the index event. In total, 337 066 all-cause hospital admissions were identified, resulting in a 5-year admission rate of 82%. Most admissions were due to nonrespiratory causes (59%), amongst which cardiac events were most common (19%).

Conclusion

Hospital admissions following a first exacerbation-related hospitalisation are common; nonrespiratory events constitute the majority of admissions. Besides the respiratory causes, treatment targeting the nonrespiratory causes of hospital admission should be considered to effectively decrease the burden of hospitalisation in COPD.

Risk of Rapid Lung Function Decline in Young Adults With Chronic Obstructive Pulmonary Disease: A Community-Based Prospective Cohort Study

It is unclear whether young adults with chronic obstructive pulmonary disease (COPD) are at an increased risk of rapid lung function decline. A total of 2,934 Korean adults aged 40-49 years who had consecutive lung function measurements were included. COPD was defined as pre-bronchodilator forced expiratory volume in 1 second (FEV₁)/forced vital capacity < lower limit of normal. The risk of rapid decline in FEV₁, defined as ≥ 60 mL/year, was assessed using multivariable logistic regression analysis. In the multivariable model, a significantly higher risk of rapid decline in FEV₁ was observed for the COPD group compared with the non-COPD group (adjusted odds ratio, 1.89; 95% confidence interval, 1.18-2.95), which was especially significant in subjects with FEV₁ less than the median value (< 110%pred) (P_interaction = 0.017) and inactive physical activity (P_interaction = 0.039). In conclusion, the risk of rapid FEV₁ decline was higher in young adults with COPD than in those without COPD, especially in those with FEV₁ less than the median value and inactive physical activity.

Inhaled corticosteroids, COPD, and the incidence of lung cancer: a systematic review and dose response meta-analysis

Background

There has been debate on whether inhaled corticosteroids (ICS) reduce the incidence of lung cancer amongst patients with Chronic Obstructive Lung Disease (COPD). We aimed to perform a systematic review and dose–response meta-analysis on available observational data.

Methods

We performed both a dose response and high versus low random effects meta-analysis on observational studies measuring whether lung cancer incidence was lower in patients using ICS with COPD. We report relative risk (RR) with 95% confidence intervals (CI), as well as risk difference. We use the GRADE framework to report our results.

Results

Our dose–response suggested a reduction in the incidence of lung cancer for every 500 ug/day of fluticasone equivalent ICS (RR 0.82 [95% 0.68–0.95]). Using a baseline risk of 7.2%, we calculated risk difference of 14 fewer cases per 1000 ([95% CI 24.7–3.8 fewer]). Similarly, our results suggested that for every 1000 ug/day of fluticasone equivalent ICS, there was a larger reduction in incidence of lung cancer (RR 0.68 [0.44–0.93]), with a risk difference of 24.7 fewer cases per 1000 ([95% CI 43.2–5.4 fewer]). The certainty of the evidence was low to very low, due to risk of bias and inconsistency.

Conclusion

There may be a reduction in the incidence for lung cancer in COPD patients who use ICS. However, the quality of the evidence is low to very low, therefore, we are limited in making strong claims about the true effect of ICS on lung cancer incidence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02072-1.

Risk factors for the development of lung cancer among never smokers: A systematic review

This review aimed to summarize the up-to-date evidence on non-genetic factors for the development of never smoking lung cancer (NSLC) and to explore reasons behind the conflicting results. Relevant literature was searched in three electronic databases (PubMed, Embase and Web of Science) from 1 January 2000-31 July 2022. Cohort studies that investigated non-genetic risk factors for primary lung cancer in never smokers were included. The effect of non-genetic factors about NSLC were summarized with pooled relative risk (RR) and 95 % confidence intervals (CIs) through meta-analysis or narrative description when unexplained statistical heterogeneity was observed. The Newcastle-Ottawa Scale was used to appraise the methodological quality of included studies. Sixty cohort studies were included, covering population from Asia, Europe and America. Most included studies (42, 70.0 %) were of high methodological quality. Over 50 years old (RR = 5.26), environmental tobacco smoke (Pooled RR = 1.30), Chronic obstructive pulmonary disease (COPD) (RR = 2.67), family history of lung cancer (Pooled RR = 1.83) and higher level of neutrophil-lymphocyte ratio (RR = 1.73) increased the risk of NSLC. Dairy foods consumption (RR = 0.79), isoflavone intake (Pooled RR = 0.65), and riboflavin intake (RR = 0.62) decreased the risk among female population. Inconsistency or unclear definition for never smokers and risk factors could be observed in included studies. Most life behavior factors associated with NSLC can be modified through lifestyle changes. Future cohort studies are suggested to adopt a clearer definition on never smokers and exposure, conducting subgroup analysis when evidence indicating there is heterogeneity between genders, and explore dose-response relationship between the identified factors and NSLC.

Lung Cancer in the Non-smoker: A Patient View Focused on the Hopes and Challenges Facing the Non-smoker Population

A patient view paper focused on hopes and challenges facing the never smoker lung cancer population - from lived experience, unexpected diagnosis, treatment and subsequent immersion in lung cancer research and patient advocacy over many years, citing examples, references and events organised to explore the subject by UK research institutions.

MATERIAL/METHODS

Based on lived experience, invited patient perspective conference presentations including National Cancer Research Institute (NCRI) never smoker lung cancer research strategy event opening presentation and subsequent article, includes references to relevant papers/findings and points raised during research events/group discussions, alongside personal experiences and beliefs.

RESULTS

Discussions with clinicians, events, surveys, meetings and virtual discussions all revealed a dearth of evidence available to identify the best way to deal with this patient cohort at almost every aspect of their experience - from missed/late diagnosis, to screening potential (non-existent), mutation driven treatments (what about those ineligible?), and psychosocial/psychological aspects given their different life stage from older traditional lung cancer patients.

CONCLUSION

More effort and focus are needed to better understand what is driving these cases, how best to detect them sooner and respond/refer to treatments as well as developing screening methods alongside increased public and healthcare professional awareness raising and tools to support clinicians in earlier detection.

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.

Inhaled Corticosteroids and the Risk of Lung Cancer in Chronic Obstructive Pulmonary Disease Patients: A Systematic Review and Meta-Analysis

Background

The global prevalence of chronic obstructive pulmonary disease (COPD) is increasing, and the risk of lung cancer in these patients is high. The use of inhaled corticosteroids (ICSs) in COPD patients could help to decrease potential lung cancer risk. We planned to conduct this systematic review and meta-analysis to determine the role of ICS in the risk of lung cancer among COPD patients.

Methods

A comprehensive search of PubMed, Science Direct, Google Scholar, and Cochrane library and a manual search of the list of references were conducted. Studies with cohort, case-control, and randomized clinical trial designs for any ICS use reporting the incidence/hazard ratio (HR) of lung cancer were included. The random-effects model was used to pool hazard ratios. Subgroup analysis and metaregression analysis were employed. Funnel plot and Egger regression test were used to assess publication bias.

Results

Combining the results of 14 observations, the pooled HR for cancer risk reduction was 0.69 (95% CI 0.59-0.79), p value ≤ 0.001. The use of ICS in COPD patients showed a 31% reduction in the risk of lung cancer. Subgroup meta-analysis showed a significant reduction in the risk of lung cancer as well.

Conclusion

The use of ICS in COPD patients reduces the risk of lung cancer. The risk reduction was independent of smoking status and latency period. Future studies should focus on the optimum dose and controlling confounders like asthma.

A Large-Scale Genome-Wide Gene-Gene Interaction Study of Lung Cancer Susceptibility in Europeans With a Trans-Ethnic Validation in Asians

INTRODUCTION

Although genome-wide association studies have been conducted to investigate genetic variation of lung tumorigenesis, little is known about gene-gene (G × G) interactions that may influence the risk of non-small cell lung cancer (NSCLC).

METHODS

Leveraging a total of 445,221 European-descent participants from the International Lung Cancer Consortium OncoArray project, Transdisciplinary Research in Cancer of the Lung and UK Biobank, we performed a large-scale genome-wide G × G interaction study on European NSCLC risk by a series of analyses. First, we used BiForce to evaluate and rank more than 58 billion G × G interactions from 340,958 single-nucleotide polymorphisms (SNPs). Then, the top interactions were further tested by demographically adjusted logistic regression models. Finally, we used the selected interactions to build lung cancer screening models of NSCLC, separately, for never and ever smokers.

RESULTS

With the Bonferroni correction, we identified eight statistically significant pairs of SNPs, which predominantly appeared in the 6p21.32 and 5p15.33 regions (e.g., rs521828C6orf10 and rs204999PRRT1, ORinteraction = 1.17, p = 6.57 × 10-13; rs3135369BTNL2 and rs2858859HLA-DQA1, ORinteraction = 1.17, p = 2.43 × 10-13; rs2858859HLA-DQA1 and rs9275572HLA-DQA2, ORinteraction = 1.15, p = 2.84 × 10-13; rs2853668TERT and rs62329694CLPTM1L, ORinteraction = 0.73, p = 2.70 × 10-13). Notably, even with much genetic heterogeneity across ethnicities, three pairs of SNPs in the 6p21.32 region identified from the European-ancestry population remained significant among an Asian population from the Nanjing Medical University Global Screening Array project (rs521828C6orf10 and rs204999PRRT1, ORinteraction = 1.13, p = 0.008; rs3135369BTNL2 and rs2858859HLA-DQA1, ORinteraction = 1.11, p = 5.23 × 10-4; rs3135369BTNL2 and rs9271300HLA-DQA1, ORinteraction = 0.89, p = 0.006). The interaction-empowered polygenetic risk score that integrated classical polygenetic risk score and G × G information score was remarkable in lung cancer risk stratification.

CONCLUSIONS

Important G × G interactions were identified and enriched in the 5p15.33 and 6p21.32 regions, which may enhance lung cancer screening models.

Chronic Obstructive Pulmonary Disease and Lung Cancer: A Review for Clinicians

Chronic obstructive pulmonary disease (COPD) and lung cancer are common global causes of morbidity and mortality. Because both diseases share several predisposing risks, the 2 diseases may occur concurrently in susceptible individuals. The diagnosis of COPD has important implications for the diagnostic approach and treatment options if lesions concerning for lung cancer are identified during screening. Importantly, the presence of COPD has significant implications on prognosis and management of patients with lung cancer. In this monograph, we review the mechanistic linkage between lung cancer and COPD, the impact of lung cancer screening on patients at risk, and the implications of the presence of COPD on the approach to the diagnosis and treatment of lung cancer. This manuscript succinctly reviews the epidemiology and common pathogenetic factors for the concurrence of COPD and lung cancer. Importantly for the clinician, it summarizes the indications, benefits, and complications of lung cancer screening in patients with COPD, and the assessment of risk factors for patients with COPD undergoing consideration of various treatment options for lung cancer.

Potential Implications of the Lung Microbiota in Patients with Chronic Obstruction Pulmonary Disease and Non-Small Cell Lung Cancer

Recently, chronic obstructive pulmonary disease (COPD) has been considered as a common risk factor of non-small cell lung cancer (NSCLC). However, very few studies have been conducted on the effects of COPD on the lung microbiota in patients with NSCLC. To identify the lung microbiota in patients with COPD and NSCLC (CN), the microbiome of the induced sputa of 90 patients was analyzed using 16S rDNA sequencing. The results showed no significant differences in the bacterial diversities of induced sputa among patients with COPD, NSCLC, and CN and no intrinsic differences among patients with different pathological types of lung cancer. After surgical operation, the diversities of the induced sputa in patients with CN significantly decreased. More remarkably, both the microbial community phenotypes and the components of the induced sputa in patients with CN obviously differed from those in patients with COPD or NSCLC. The relative abundances of Streptococcus, Veillonella, Moraxella, and Actinomyces significantly decreased, but those of Neisseria and Acinetobacter significantly increased in patients with CN compared with those in patients with COPD or NSCLC alone, resulting in increased Gram-negative microbiota and, therefore, in potential pathogenicity and stress tolerance, as well as in enhancement of microbial glycolipid metabolism, amino acid metabolism, and oxidative stress. Although COPD did not affect the number of pulmonary flora species in patients with NSCLC, these significant alterations in the microbial populations, phenotypes, and functions of induced sputa due to COPD would contribute to inflammation-derived cancer progression in patients with CN.

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.

Airflow Limitation Increases Lung Cancer Risk in Smokers: The Lifelines Cohort Study

BACKGROUND

The relationship between smoking, airflow limitation, and lung cancer occurrence is unclear. This study aims to evaluate the relationship between airflow limitation and lung cancer, and the effect modification by smoking status.

METHODS

We included participants with spirometry data from Lifelines, a population-based cohort study from the Northern Netherlands. Airflow limitation was defined as FEV1/FVC ratio < 0.7. The presence of pathology-confirmed primary lung cancer during a median follow-up of 9.5 years was collected. The Cox regression model was used and hazard ratios (HR) with 95% confidence interval (95% CI) were reported. Adjusted confounders included age, sex, educational level, smoking, passive smoking, asthma status and asbestos exposure. The effect modification by smoking status was investigated by estimating the relative excess risk due to interaction (RERI) and the ratio of HRs with 95% CI.

RESULTS

Out of 98,630 participants, 14,200 (14.4%) had airflow limitation. In participants with and without airflow limitation, lung cancer incidence was 0.8% and 0.2%, respectively. The adjusted HR between airflow limitation and lung cancer risk was 1.7 (1.4-2.3). The association between airflow limitation and lung cancer differed by smoking status [former smokers: 2.1 (1.4-3.2), current smokers: 2.2 (1.5-3.2)] and never smokers [0.9 (0.4-2.1)]. The RERI and ratio of HRs was 2.1 (0.7-3.4) and 2.5 (1.0-6.5) for former smokers, and 4.6 (95% CI, 1.8-7.4) and 2.5 (95% CI, 1.0-6.3) for current smokers, respectively.

CONCLUSIONS

Airflow limitation increases lung cancer risk and this association is modified by smoking status.

IMPACT

Ever smokers with airflow limitation are an important target group for the prevention of lung cancer.

Risk Factors of Incident Lung Cancer in Patients with Non-Cystic Fibrosis Bronchiectasis: A Korean Population-Based Study

BACKGROUND

Patients with non-cystic fibrosis bronchiectasis have an increased risk of lung cancer, followed by higher mortality in this population. Because the risk factors of lung cancer have not been well identified, this study aimed to investigate the risk factors of lung cancer in individuals with newly diagnosed bronchiectasis.

METHODS

This cohort study using the Korean National Health Insurance Service database identified 7425 individuals with incident bronchiectasis among those who participated in the health screening exam in 2009. The cohort was followed from baseline to the date of incident: lung cancer, death, or until the end of the study period. We investigated the risk factors of lung cancer in participants with bronchiectasis using the Cox-proportional hazard models.

RESULTS

During median 8.3 years of follow-up duration, 1.9% (138/7425) developed lung cancer. In multivariable analyses, significant factors associated with increased risk of incident lung cancer included: males (adjusted hazard ratio [HR] = 3.54, 95% confidence interval [CI] = 2.17-5.79) than females, the overweight (adjusted HR = 1.55, 95% CI = 1.03-2.35) than the normal weight, current smokers (adjusted HR = 3.10, 95% CI = 2.00-4.79) than never smokers, participants living in the rural area (adjusted HR = 2.54, 95% CI = 1.68-3.85) than those living in the metropolitan area. Among comorbidities, chronic obstructive pulmonary disease was associated with an increased risk of lung cancer (adjusted HR = 1.46, 95% CI = 1.01-2.13) in participants with bronchiectasis. In contrast, mild alcohol consumption was associated with reduced risk of lung cancer (adjusted HR = 0.47, 95% CI = 0.29-0.74) in those with bronchiectasis.

CONCLUSION

This Korean population-based study showed that males, current smoking, overweight, living in rural areas, and comorbid chronic obstructive pulmonary disease are associated with increased risk of lung cancer in individuals with bronchiectasis.

Non-Cystic Fibrosis Bronchiectasis Increases the Risk of Lung Cancer Independent of Smoking Status

Rationale

It remains unclear whether non-cystic fibrosis bronchiectasis increases the risk of lung cancer, because smoking history was not considered in previous studies.

Objectives

To evaluate whether participants with bronchiectasis have a higher risk of incident lung cancer than those without bronchiectasis with information on smoking status.

Methods

This was a population-based cohort study of 3,858,422 individuals who participated in the 2009 National Health Screening Program. We evaluated the incidence of lung cancer in participants with bronchiectasis (n = 65,305) and those without bronchiectasis (n = 3,793,117). We followed the cohort up until the date of lung cancer diagnosis, date of death, or December 2018. Cox proportional hazard regression models were used to evaluate the relative risk of lung cancer between participants with bronchiectasis and those without bronchiectasis.

Results

The incidence of lung cancer in participants with bronchiectasis was significantly higher than in those without bronchiectasis (2.1 vs. 0.7 per 1,000 person-years; P < 0.001), with an adjusted hazard ratio (aHR) of 1.22 (95% confidence interval [CI], 1.14–1.30) in the model adjusting for potential confounders and accounting for the competing risk of mortality. Regardless of smoking status, the risk of lung cancer was significantly higher in participants with bronchiectasis than in those without bronchiectasis (aHR, 1.28 [95% CI, 1.17–1.41] for never-smokers; aHR, 1.26 [95% CI, 1.10–1.44] for ever-smokers). Although bronchiectasis did not increase the risk of lung cancer among participants with chronic obstructive pulmonary disease (COPD), it significantly increased the risk of lung cancer in participants without COPD (aHR, 1.19 [95% CI, 1.09–1.31]).

Conclusions

The presence of bronchiectasis was associated with a higher risk of lung cancer after considering the smoking status.

Chronic obstructive pulmonary disease in never-smokers: risk factors, pathogenesis, and implications for prevention and treatment

Chronic obstructive pulmonary disease (COPD) was traditionally thought to be caused by tobacco smoking. However, recognition of the importance of non-smoking-related risk factors for COPD has increased over the past decade, with evidence on the burden, risk factors, and clinical presentations of COPD in never-smokers. About half of all COPD cases worldwide are due to non-tobacco-related risk factors, which vary by geographical region. These factors include air pollution, occupational exposures, poorly controlled asthma, environmental tobacco smoke, infectious diseases, and low socioeconomic status. Impaired lung growth during childhood, caused by a range of early-life exposures, is associated with an increased risk of COPD. Potential mechanisms for the pathogenesis of COPD in never-smokers include inflammation, oxidative stress, airway remodelling, and accelerated lung ageing. Compared with smokers who develop COPD, never-smokers with COPD have relatively mild chronic respiratory symptoms, little or no emphysema, milder airflow limitation, and fewer comorbidities; however, exacerbations can still be frequent. Further research-including epidemiological, translational, clinical, and implementation studies-is needed to address gaps in understanding and to advance potential solutions to reduce the burden of COPD in never-smokers.

Reduced FEV1 as Prognostic Factors in Patients With Advanced NSCLC Receiving Immune Checkpoint Inhibitors

Background

The aim of study is to investigate the influence of pulmonary function on the prognosis in patients with advanced non-small cell lung cancer (NSCLC) receiving immune checkpoint inhibitors (ICI).

Patients and Methods

Data were collected retrospectively from 151 patients with stage IV NSCLC who received ICI and completed spirometry before ICI therapy in Taipei Veterans General Hospital between January 2016 and December 2020. The co-primary end points were overall survival (OS) and progression-free survival (PFS) between groups divided by 80% predicted FEV₁ since ICI therapy started; the secondary outcomes were objective response rate.

Results

Among 151 patients enrolled to this study, 67.5% of patients were men, 75.5% were adenocarcinoma, 24.5% had known targetable driver mutation, 33.8% received first-line ICI, and 62.8% received ICI monotherapy. The objective response rate was 24.5% and disease control rate was 54.3%. In multivariable analysis, patient with reduced FEV₁ had inferior PFS (FEV₁ < 80% vs. FEV₁ ≥ 80%, adjusted HR = 1.80, P = 0.006) and OS (FEV₁ < 80% vs. FEV₁ ≥ 80%, adjusted HR = 2.50, P < 0.001). Median PFS and OS in the preserved FEV₁ group (≥80% predicted FEV₁) compared to the reduced FEV₁ group (<80% predicted FEV₁) were 5.4 vs. 2.9 months (HR = 1.76, P = 0.003) and 34.9 vs. 11.1 months (HR = 2.44, P < 0.001), respectively. The other independent prognostic factors of OS include stage IVA disease (adjusted HR = 0.57, P = 0.037), initial liver metastasis (adjusted HR = 2.00, P = 0.049), ICI monotherapy (adjusted HR = 1.73, P = 0.042) and ICI related pneumonitis (adjusted HR = 3 .44, P = 0.025).

Conclusions

Reduced FEV₁ is strongly associated with inferior clinical outcomes in patients with advanced NSCLC treated with ICI.

Increased hospitalizations and economic burden in COPD with bronchiectasis: a nationwide representative study

With the increasing use of computed tomography, bronchiectasis has become a common finding in patients with chronic obstructive pulmonary disease (COPD). However, the clinical aspects and medical utilization of COPD with bronchiectasis (BE) remain unclear. We aimed to investigate the BE effect on prognosis and medical utilization in patients with COPD. Among 263,747 COPD patients, we excluded patients lacking chest X-ray, CT, or pulmonary function test codes and classified 2583 GOLD-C/D patients matched according to age, sex, and medical aid as having COPD-BE (447 [17.3%]) and COPD without BE (2136 [82.7%]). Patients with COPD-BE showed a higher rate of acute exacerbation requiring antibiotics than those without BE. Moreover, multivariable analysis showed that BE co-existence was a crucial factor for moderate-to-severe exacerbation (incidence rate ratio [IRR] 1.071; 95% CI 1.012-1.134; p = 0.019). Patients with COPD-BE had a significantly higher rate of exacerbations requiring antibiotics, as well as treatment cost and duration (meant as number of days using hospitalization plus outpatient appointment), than those with COPD without BE (52.64 ± 65.29 vs. 40.19 ± 50.02 days, p < 0.001; 5984.08 ± 8316.96 vs. 4453.40 ± 7291.03 USD, p < 0.001). Compared with patients with COPD without BE, patients with COPD-BE experienced more exacerbations requiring antibiotics, more hospitalizations, and a higher medical cost.

Extracellular Vesicles as Central Mediators of COPD Pathophysiology

Chronic obstructive pulmonary disease (COPD) is a complex, heterogeneous, smoking-related disease of significant global impact. The complex biology of COPD is ultimately driven by a few interrelated processes, including proteolytic tissue remodeling, innate immune inflammation, derangements of the host-pathogen response, aberrant cellular phenotype switching, and cellular senescence, among others. Each of these processes are engendered and perpetuated by cells modulating their environment or each other. Extracellular vesicles (EVs) are powerful effectors that allow cells to perform a diverse array of functions on both adjacent and distant tissues, and their pleiotropic nature is only beginning to be appreciated. As such, EVs are candidates to play major roles in these fundamental mechanisms of disease behind COPD. Furthermore, some such roles for EVs are already established, and EVs are implicated in significant aspects of COPD pathogenesis. Here, we discuss known and potential ways that EVs modulate the environment of their originating cells to contribute to the processes that underlie COPD.