Assessing the relationship between lung cancer risk and emphysema detected on low-dose CT of the chest

Machine learning computational model to predict lung cancer using electronic medical records

BACKGROUND

Lung cancer (LC) screening using low-dose computed tomography (CT) is recommended according to standard risk criteria or personalized risk calculators. Machine learning (ML) models that can predict disease risk are an emerging method in medicine for identifying hidden associations that are personally unique.

MATERIALS AND METHODS

Using the tree-based pipeline optimization tool (TPOT), we developed an ML-based model, which is an ensemble of the Random Forest and XGboost models, based on known risk factors for LC, as part of a larger trial for ML prediction using electronic medical records and chest CT. We used data from patients with LC vs. controls (1:2) of patients aged ≥ 35 years. We developed a model for all LC patients as well as for patients with and without a smoking background. We included age, gender, body mass index (BMI), smoking history, socioeconomic status (SES), history of chronic obstructive pulmonary disease (COPD)/emphysema/chronic bronchitis (CB), interstitial lung disease (ILD)/pulmonary fibrosis (PF), and family history of LC.

RESULTS

Of the 4076 patients, 1428 (35 %) were in the LC group and 2648 (65 %) were in the control group. For the entire study population, our model achieved an accuracy of 71.2 %, with a sensitivity of 69 % and a positive predictive value (PPV) of 74 %. Higher accuracy was achieved for the two subgroups. An accuracy of 74.8 % (sensitivity 72 %, PPV 76 %) and 73.0 % (sensitivity 76 %, PPV 72 %) was achieved for the smoking and never-smoking cohorts, respectively. For the entire population and smoker cohort, COPD/emphysema/CB were the most important contributors, followed by BMI and age, while in the never-smoking cohort, BMI, age and SES were the most important contributors.

CONCLUSION

Known risk factors for LC could be used in ML models to modestly predict LC. Further studies are needed to confirm these results in new patients and to improve them.

Impact of OLD/Emphysema in LC Mortality Risk in Screening Programs: An Analysis of NLST and P-IELCAP

INTRODUCTION

The impact of obstructive lung disease (OLD) and emphysema on lung cancer (LC) mortality in patients undergoing LC screening is controversial.

METHODS

Patients with spirometry and LC diagnosed within the first three rounds of screening were selected from the National Lung Screening Trial (NLST) and from the Pamplona International Early Lung Cancer Detection Program (P-IELCAP). Medical and demographic data, tumor characteristics, comorbidities and presence of emphysema were collected. The effect of OLD and emphysema on the risk of overall survival was assessed using unadjusted and adjusted Cox models, competing risk regression analysis, and propensity score matching.

RESULTS

Data from 353 patients with LC, including 291 with OLD and/or emphysema and 62 with neither, were analyzed. The median age was 67.3 years-old and 56.1% met OLD criteria, predominantly mild (1: 28.3%, 2: 65.2%). Emphysema was present in 69.4% of the patients. Patients with OLD and/or emphysema had worse survival on univariate analysis (HR: 1.40; 95% CI: 0.86-2.31; p=0.179). However, after adjusting for LC stage, age, and sex, the HR was 1.02 (95% CI: 0.61-1.70; p=0.952). Specific LC survival between both groups showed an adjusted HR of 0.90 (95% CI: 0.47-1.72; p=0.76). Propensity score matching found no statistically significant difference in overall survival (HR: 1.03; 95% CI: 0.59-1.9; p=0.929).

CONCLUSION

The survival of LC patients diagnosed in the context of screening is not negatively impacted by the coexistence of mild OLD and/or emphysema.

Precision therapy for cancer prevention by targeting carcinogenesis

Cancer represents a major global public health burden, with new cases estimated to increase from 14 million in 2012 to 24 million by 2035. Primary prevention is an effective strategy to reduce the costs associated with cancer burden. For example, measures to ban tobacco consumption have dramatically decreased lung cancer incidence and vaccination against human papillomavirus can prevent cervical cancer development. Unfortunately, the etiological factors of many cancer types are not completely clear or are difficult to actively control; therefore, the primary prevention of such cancers is not practical. In this review, we update the progress on precision therapy by targeting the whole carcinogenesis process, especially for three high-risk groups: (1) those with chronic inflammation, (2) those with inherited germline mutations, and (3) those with precancerous lesions like polyps, gastritis, actinic keratosis or dysplasia. We believe that attenuating chronic inflammation, treating precancerous lesions, and removing high-risk tissues harboring germline mutations are precision methods for cancer prevention.

Lung Hyperinflation as Treatable Trait in Chronic Obstructive Pulmonary Disease: A Narrative Review

Lung hyperinflation (LH) is a common clinical feature in patients with chronic obstructive pulmonary disease (COPD). It results from a combination of reduced elastic lung recoil as a consequence of irreversible destruction of lung parenchyma and expiratory airflow limitation. LH is an important determinant of morbidity and mortality in COPD, partially independent of the degree of airflow limitation. Therefore, reducing LH has become a major target in the treatment of COPD over the last decades. Advances were made in the diagnostics of LH and several effective interventions became available. Moreover, there is increasing evidence suggesting that LH is not only an isolated feature in COPD but rather part of a distinct clinical phenotype that may require a more integrated management. This narrative review focuses on the pathophysiology and adverse consequences of LH, the assessment of LH with lung function measurements and imaging techniques and highlights LH as a treatable trait in COPD. Finally, several suggestions regarding future studies in this field are made.

LDCT image biomarkers that matter most for the deep learning classification of indeterminate pulmonary nodules

BACKGROUND

Continued improvement in deep learning methodologies has increased the rate at which deep neural networks are being evaluated for medical applications, including diagnosis of lung cancer. However, there has been limited exploration of the underlying radiological characteristics that the network relies on to identify lung cancer in computed tomography (CT) images.

OBJECTIVE

In this study, we used a combination of image masking and saliency activation maps to systematically explore the contributions of both parenchymal and tumor regions in a CT image to the classification of indeterminate lung nodules.

METHODS

We selected individuals from the National Lung Screening Trial (NLST) with solid pulmonary nodules 4-20 mm in diameter. Segmentation masks were used to generate three distinct datasets; 1) an Original Dataset containing the complete low-dose CT scans from the NLST, 2) a Parenchyma-Only Dataset in which the tumor regions were covered by a mask, and 3) a Tumor-Only Dataset in which only the tumor regions were included.

RESULTS

The Original Dataset significantly outperformed the Parenchyma-Only Dataset and the Tumor-Only Dataset with an AUC of 80.80 ± 3.77% compared to 76.39 ± 3.16% and 78.11 ± 4.32%, respectively. Gradient-weighted class activation mapping (Grad-CAM) of the Original Dataset showed increased attention was being given to the nodule and the tumor-parenchyma boundary when nodules were classified as malignant. This pattern of attention remained unchanged in the case of the Parenchyma-Only Dataset. Nodule size and first-order statistical features of the nodules were significantly different with the average malignant and benign nodule maximum 3d diameter being 23 mm and 12 mm, respectively.

CONCLUSION

We conclude that network performance is linked to textural features of nodules such as kurtosis, entropy and intensity, as well as morphological features such as sphericity and diameter. Furthermore, textural features are more positively associated with malignancy than morphological features.

Multidisciplinary virtual management of pulmonary nodules

INTRODUCTION AND OBJECTIVES

Multidisciplinary nodule clinics provide high-quality care and favor adherence to guidelines. Virtual care has shown savings benefits along with patient satisfaction. Our aim is to describe the first year of operation of a multidisciplinary virtual lung nodule clinic, the population evaluated and issued decisions. Secondarily, among discharged patients, we aimed to analyze their follow-up prior to the existence of our consultation, evaluating its adherence to guidelines.

MATERIALS AND METHODS

Observational study including all patients evaluated at the Virtual Lung Nodule Clinic (VLNC) (March 2018- March 2019). Clinical and radiological data were recorded. Recommendations, based on 2017 Fleischner Society guidelines, were categorized into follow-up, discharge or referral to lung cancer consultation. Discharged patients were classified according to adherence to guidelines of their previous management, into adequate, prolonged and non-indicated follow-up.

RESULTS

A total of 365 patients (58.9% men; median age 64.0 years) were included. Sixty-four percent had smoking history and 23% had chronic obstructive pulmonary disease (COPD). Most nodules were solid (87.4%) and multiple (57.5%). The median diameter was 6.00 mm. 43.8% of patients were discharged following first VLNC evaluation. Among them, 27.5% had received appropriate follow-up, but 66.9% had received poor management. Patients with prolonged follow-up (33.1%) were older (67.0 vs 60.5 years) and had larger nodules (6.00 mm vs 5.00). Non-indicated follow-up patients (33.8%) were more non-smokers (77.8% vs 31.8%) and presented smaller nodules (4.00 vs 5.00 mm).

CONCLUSIONS

During its first year of operation, the VLNC has evaluated a population with a relevant risk profile for lung cancer development, management of which should be cautious and adhere to guidelines. After the first VLNC assessment, approximately one-half of this population was discharged. It was noticeable that previous follow-up of discharged patients was found poorly adherent to guidelines, with a marked tendency to overmanagement.

Sex-specific emphysematous changes evaluated by a three-dimensional computed tomography volumetric analysis among patients with smoking histories who underwent resection for lung cancer

PURPOSE

The present study evaluated the sex-specific susceptibility to the development of emphysema in patients with smoking histories who underwent lung cancer surgeries.

METHODS

Lung cancer patients with smoking histories who underwent lung resection at the University of Tsukuba Hospital, Japan, were enrolled. Radiologic emphysematous changes were analyzed using three-dimensional computed tomography (3D-CT). The volume proportion of emphysematous lung per unit of smoking and the relationship between emphysematous change and clinicopathologic factors were evaluated.

RESULTS

Radiologic emphysematous changes analyzed using 3D-CT per pack-year smoked, defined as the Smoking-Emphysema Index (SEI), were greater in females than males. The difference was more profound in adenocarcinoma patients than in non-adenocarcinoma patients (0.70 ± 2.30 vs. 0.21 ± 0.28, P = 0.037).

CONCLUSION

Female lung cancer patients are more susceptible to smoking-induced emphysema than males. The SEI may be an effective indicator for evaluating smoking-induced emphysema.

Lung Cancer Screening in People With COPD: The Pamplona-IELCAP Experience

INTRODUCTION

The Global Initiative for Obstructive Lung Disease (GOLD) recommends lung cancer screening for patients with Chronic Obstructive Pulmonary Disease (COPD), but data is lacking regarding results of screening in this high-risk population. The main goal of the present work is to explore if lung cancer screening with Low Dose Chest Tomography (LDCT) in people with COPD, allows lung cancer (LC) diagnosis in early stages with survival compatible with curative state.

METHODS

This is a post hoc exploratory analysis. Pamplona International Early Lung Cancer Action Program (P-IELCAP) participants with a GOLD defined obstructive pattern (post bronchodilator FEV1/FVC<0.70) were selected for analysis. The characteristics of those who developed LC and their survival are described. A Cox proportional analysis explored the factors associated with LC diagnosis.

RESULTS

Eight hundred and sixty-five patients (77% male, 93% in spirometric GOLD stage 1+2) were followed for 102±63 months. LC prevalence was 2.6% at baseline, with an annual LC diagnosis rate of 0.68%. Early-stage tumors predominated (74%) with a median survival (25-75th percentiles) of 139 (76-185) months. Cumulative tobacco exposure, FEV1%, and emphysema were the main predictors of an LC diagnosis. Eight (11%) patients with COPD had a second LC, most of them in early stage (92%), and 6 (8%) had recurrence. Median survival (25-75th percentiles) in these patients was 168 (108-191) months.

CONCLUSIONS

Lung cancer screening of selected high-risk participants with COPD allowed the LC diagnosis in early stages with survival compatible with curative state.

The International Association for the Study of Lung Cancer Early Lung Imaging Confederation Open-Source Deep Learning and Quantitative Measurement Initiative

INTRODUCTION

With global adoption of computed tomography (CT) lung cancer screening, there is increasing interest to use artificial intelligence (AI) deep learning methods to improve the clinical management process. To enable AI research using an open-source, cloud-based, globally distributed, screening CT imaging data set and computational environment that are compliant with the most stringent international privacy regulations that also protect the intellectual properties of researchers, the International Association for the Study of Lung Cancer sponsored development of the Early Lung Imaging Confederation (ELIC) resource in 2018. The objective of this report is to describe the updated capabilities of ELIC and illustrate how this resource can be used for clinically relevant AI research.

METHODS

In this second phase of the initiative, metadata and screening CT scans from two time points were collected from 100 screening participants in seven countries. An automated deep learning AI lung segmentation algorithm, automated quantitative emphysema metrics, and a quantitative lung nodule volume measurement algorithm were run on these scans.

RESULTS

A total of 1394 CTs were collected from 697 participants. The LAV950 quantitative emphysema metric was found to be potentially useful in distinguishing lung cancer from benign cases using a combined slice thickness more than or equal to 2.5 mm. Lung nodule volume change measurements had better sensitivity and specificity for classifying malignant from benign lung nodules when applied to solid lung nodules from high-quality CT scans.

CONCLUSIONS

These initial experiments revealed that ELIC can support deep learning AI and quantitative imaging analyses on diverse and globally distributed cloud-based data sets.

ERS International Congress 2023: highlights from the Thoracic Oncology Assembly

Lung cancer is the leading cause of cancer mortality in the world. It greatly affects the patients' quality of life, and is thus a challenge for the daily practice in respiratory medicine. Advances in the genetic knowledge of thoracic tumours' mutational landscape, and the development of targeted therapies and immune checkpoint inhibitors, have led to a paradigm shift in the treatment of lung cancer and pleural mesothelioma. During the 2023 European Respiratory Society Congress in Milan, Italy, experts from all over the world presented their high-quality research and reviewed best clinical practices. Lung cancer screening, management of early stages of lung cancer, application of artificial intelligence and biomarkers were discussed and they will be summarised here.

ERS/ESTS/ESTRO/ESR/ESTI/EFOMP statement on management of incidental findings from low dose CT screening for lung cancer

BACKGROUND

Screening for lung cancer with low radiation dose computed tomography has a strong evidence base, is being introduced in several European countries and is recommended as a new targeted cancer screening programme. The imperative now is to ensure that implementation follows an evidence-based process that will ensure clinical and cost effectiveness. This European Respiratory Society (ERS) task force was formed to provide an expert consensus for the management of incidental findings which can be adapted and followed during implementation.

METHODS

A multi-European society collaborative group was convened. 23 topics were identified, primarily from an ERS statement on lung cancer screening, and a systematic review of the literature was conducted according to ERS standards. Initial review of abstracts was completed and full text was provided to members of the group for each topic. Sections were edited and the final document approved by all members and the ERS Science Council.

RESULTS

Nine topics considered most important and frequent were reviewed as standalone topics (interstitial lung abnormalities, emphysema, bronchiectasis, consolidation, coronary calcification, aortic valve disease, mediastinal mass, mediastinal lymph nodes and thyroid abnormalities). Other topics considered of lower importance or infrequent were grouped into generic categories, suitable for general statements.

CONCLUSIONS

This European collaborative group has produced an incidental findings statement that can be followed during lung cancer screening. It will ensure that an evidence-based approach is used for reporting and managing incidental findings, which will mean that harms are minimised and any programme is as cost-effective as possible.

ERS/ESTS/ESTRO/ESR/ESTI/EFOMP statement on management of incidental findings from low dose CT screening for lung cancer

BACKGROUND

Screening for lung cancer with low radiation dose computed tomography has a strong evidence base, is being introduced in several European countries and is recommended as a new targeted cancer screening programme. The imperative now is to ensure that implementation follows an evidence-based process that will ensure clinical and cost effectiveness. This European Respiratory Society (ERS) task force was formed to provide an expert consensus for the management of incidental findings which can be adapted and followed during implementation.

METHODS

A multi-European society collaborative group was convened. 23 topics were identified, primarily from an ERS statement on lung cancer screening, and a systematic review of the literature was conducted according to ERS standards. Initial review of abstracts was completed and full text was provided to members of the group for each topic. Sections were edited and the final document approved by all members and the ERS Science Council.

RESULTS

Nine topics considered most important and frequent were reviewed as standalone topics (interstitial lung abnormalities, emphysema, bronchiectasis, consolidation, coronary calcification, aortic valve disease, mediastinal mass, mediastinal lymph nodes and thyroid abnormalities). Other topics considered of lower importance or infrequent were grouped into generic categories, suitable for general statements.

CONCLUSIONS

This European collaborative group has produced an incidental findings statement that can be followed during lung cancer screening. It will ensure that an evidence-based approach is used for reporting and managing incidental findings, which will mean that harms are minimised and any programme is as cost-effective as possible.

[Surgical or bronchoscopic lung volume reduction for emphysema therapy]

More than 20 years ago, surgical lung volume reduction (LVRS) was already established in patients with advanced emphysema as a palliative therapy option that reduces respiratory distress and improves lung function and quality of life. In addition, bronchoscopic procedures (BLVR) aimed at volume reduction have existed for just over 10 years. The advantages and disadvantages of LVRS and BLVR are discussed in this article.

Automated Coronary Artery Calcium and Quantitative Emphysema in Lung Cancer Screening: Association With Mortality, Lung Cancer Incidence, and Airflow Obstruction

PURPOSE

To assess automated coronary artery calcium (CAC) and quantitative emphysema (percentage of low attenuation areas [%LAA]) for predicting mortality and lung cancer (LC) incidence in LC screening. To explore correlations between %LAA, CAC, and forced expiratory value in 1 second (FEV 1 ) and the discriminative ability of %LAA for airflow obstruction.

MATERIALS AND METHODS

Baseline low-dose computed tomography scans of the BioMILD trial were analyzed using an artificial intelligence software. Univariate and multivariate analyses were performed to estimate the predictive value of %LAA and CAC. Harrell C -statistic and time-dependent area under the curve (AUC) were reported for 3 nested models (Model survey : age, sex, pack-years; Model survey-LDCT : Model survey plus %LAA plus CAC; Model final : Model survey-LDCT plus selected confounders). The correlations between %LAA, CAC, and FEV 1 and the discriminative ability of %LAA for airflow obstruction were tested using the Pearson correlation coefficient and AUC-receiver operating characteristic curve, respectively.

RESULTS

A total of 4098 volunteers were enrolled. %LAA and CAC independently predicted 6-year all-cause (Model final hazard ratio [HR], 1.14 per %LAA interquartile range [IQR] increase [95% CI, 1.05-1.23], 2.13 for CAC ≥400 [95% CI, 1.36-3.28]), noncancer (Model final HR, 1.25 per %LAA IQR increase [95% CI, 1.11-1.37], 3.22 for CAC ≥400 [95%CI, 1.62-6.39]), and cardiovascular (Model final HR, 1.25 per %LAA IQR increase [95% CI, 1.00-1.46], 4.66 for CAC ≥400, [95% CI, 1.80-12.58]) mortality, with an increase in concordance probability in Model survey-LDCT compared with Model survey ( P <0.05). No significant association with LC incidence was found after adjustments. Both biomarkers negatively correlated with FEV 1 ( P <0.01). %LAA identified airflow obstruction with a moderate discriminative ability (AUC, 0.738).

CONCLUSIONS

Automated CAC and %LAA added prognostic information to age, sex, and pack-years for predicting mortality but not LC incidence in an LC screening setting. Both biomarkers negatively correlated with FEV 1 , with %LAA enabling the identification of airflow obstruction with moderate discriminative ability.

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.

Perinodular Parenchymal Features Improve Indeterminate Lung Nodule Classification

BACKGROUND

Radiomics, defined as quantitative features extracted from images, provide a non-invasive means of assessing malignant versus benign pulmonary nodules. In this study, we evaluate the consistency with which perinodular radiomics extracted from low-dose computed tomography images serve to identify malignant pulmonary nodules.

MATERIALS AND METHODS

Using the National Lung Screening Trial (NLST), we selected individuals with pulmonary nodules between 4mm to 20mm in diameter. Nodules were segmented to generate four distinct datasets; 1) a Tumor dataset containing tumor-specific features, 2) a 10 mm Band dataset containing parenchymal features between the segmented nodule boundary and 10mm out from the boundary, 3) a 15mm Band dataset, and 4) a Tumor Size dataset containing the maximum nodule diameter. Models to predict malignancy were constructed using support-vector machine (SVM), random forest (RF), and least absolute shrinkage and selection operator (LASSO) approaches. Ten-fold cross validation with 10 repetitions per fold was used to evaluate the performance of each approach applied to each dataset.

RESULTS

With respect to the RF, the Tumor, 10mm Band, and 15mm Band datasets achieved areas under the receiver-operator curve (AUC) of 84.44%, 84.09%, and 81.57%, respectively. Significant differences in performance were observed between the Tumor and 15mm Band datasets (adj. p-value <0.001). However, when combining tumor-specific features with perinodular features, the 10mm Band + Tumor and 15mm Band + Tumor datasets (AUC 87.87% and 86.75%, respectively) performed significantly better than the Tumor Size dataset (66.76%) or the Tumor dataset. Similarly, the AUCs from the SVM and LASSO were 84.71% and 88.91%, respectively, for the 10mm Band + Tumor.

CONCLUSIONS

The combined 10mm Band + Tumor dataset improved the differentiation between benign and malignant lung nodules compared to the Tumor datasets across all methodologies. This demonstrates that parenchymal features capture novel diagnostic information beyond that present in the nodule itself. (data agreement: NLST-163).

New opportunities for RGD-engineered metal nanoparticles in cancer

The advent of nanotechnology has opened new possibilities for bioimaging. Metal nanoparticles (such as gold, silver, iron, copper, etc.) hold tremendous potential and offer enormous opportunities for imaging and diagnostics due to their broad optical characteristics, ease of manufacturing technique, and simple surface modification. The arginine-glycine-aspartate (RGD) peptide is a three-amino acid sequence that seems to have a considerably greater ability to adhere to integrin adhesion molecules that exclusively express on tumour cells. RGD peptides act as the efficient tailoring ligand with a variety of benefits including non-toxicity, greater precision, rapid clearance, etc. This review focuses on the possibility of non-invasive cancer imaging using metal nanoparticles with RGD assistance.

Circulating Hsp70 Levels and the Immunophenotype of Peripheral Blood Lymphocytes as Potential Biomarkers for Advanced Lung Cancer and Therapy Failure after Surgery

Lung cancer remains a devastating disease with a poor clinical outcome. A biomarker signature which could distinguish lung cancer from metastatic disease and detect therapeutic failure would significantly improve patient management and allow for individualized, risk-adjusted therapeutic decisions. In this study, circulating Hsp70 levels were measured using ELISA, and the immunophenotype of the peripheral blood lymphocytes were measured using multiparameter flow cytometry, to identify a predictive biomarker signature for lung cancer patients pre- and post-operatively, in patients with lung metastases and in patients with COPD as an inflammatory lung disease. The lowest Hsp70 concentrations were found in the healthy controls followed by the patients with advanced COPD. Hsp70 levels sequentially increased with an advancing tumor stage and metastatic disease. In the early-recurrence patients, Hsp70 levels started to increase within the first three months after surgery, but remained unaltered in the recurrence-free patients. An early recurrence was associated with a significant drop in B cells and an increase in Tregs, whereas the recurrence-free patients had elevated T and NK cell levels. We conclude that circulating Hsp70 concentrations might have the potential to distinguish lung cancer from metastatic disease, and might be able to predict an advanced tumor stage and early recurrence in lung cancer patients. Further studies with larger patient cohorts and longer follow-up periods are needed to validate Hsp70 and immunophenotypic profiles as predictive biomarker signatures.

Lung cancer screening

Randomised controlled trials, including the National Lung Screening Trial (NLST) and the NELSON trial, have shown reduced mortality with lung cancer screening with low-dose CT compared with chest radiography or no screening. Although research has provided clarity on key issues of lung cancer screening, uncertainty remains about aspects that might be critical to optimise clinical effectiveness and cost-effectiveness. This Review brings together current evidence on lung cancer screening, including an overview of clinical trials, considerations regarding the identification of individuals who benefit from lung cancer screening, management of screen-detected findings, smoking cessation interventions, cost-effectiveness, the role of artificial intelligence and biomarkers, and current challenges, solutions, and opportunities surrounding the implementation of lung cancer screening programmes from an international perspective. Further research into risk models for patient selection, personalised screening intervals, novel biomarkers, integrated cardiovascular disease and chronic obstructive pulmonary disease assessments, smoking cessation interventions, and artificial intelligence for lung nodule detection and risk stratification are key opportunities to increase the efficiency of lung cancer screening and ensure equity of access.

Evaluation of emphysema on thoracic low-dose CTs through attention-based multiple instance deep learning

In addition to lung cancer, other thoracic abnormalities, such as emphysema, can be visualized within low-dose CT scans that were initially obtained in cancer screening programs, and thus, opportunistic evaluation of these diseases may be highly valuable. However, manual assessment for each scan is tedious and often subjective, thus we have developed an automatic, rapid computer-aided diagnosis system for emphysema using attention-based multiple instance deep learning and 865 LDCTs. In the task of determining if a CT scan presented with emphysema or not, our novel Transfer AMIL approach yielded an area under the ROC curve of 0.94 ± 0.04, which was a statistically significant improvement compared to other methods evaluated in our study following the Delong Test with correction for multiple comparisons. Further, from our novel attention weight curves, we found that the upper lung demonstrated a stronger influence in all scan classes, indicating that the model prioritized upper lobe information. Overall, our novel Transfer AMIL method yielded high performance and provided interpretable information by identifying slices that were most influential to the classification decision, thus demonstrating strong potential for clinical implementation.

Detection of COPD in the SUMMIT Study lung cancer screening cohort using symptoms and spirometry

BACKGROUND

COPD is a major comorbidity in lung cancer screening (LCS) cohorts, with a high prevalence of undiagnosed COPD. Combining symptom assessment with spirometry in this setting may enable earlier diagnosis of clinically significant COPD and facilitate increased understanding of lung cancer risk in COPD. In this study, we wished to understand the prevalence, severity, clinical phenotype and lung cancer risk of individuals with symptomatic undiagnosed COPD in a LCS cohort.

METHODS

16 010 current or former smokers aged 55-77 years attended a lung health check as part of the SUMMIT Study. A respiratory consultation and spirometry were performed alongside LCS eligibility assessment. Those with symptoms, no previous COPD diagnosis and airflow obstruction were labelled as undiagnosed COPD. Baseline low-dose computed tomography (LDCT) was performed in those at high risk of lung cancer (PLCOm2012 score ≥1.3% and/or meeting USPSTF 2013 criteria).

RESULTS

Nearly one in five (19.7%) met criteria for undiagnosed COPD. Compared with those previously diagnosed, those undiagnosed were more likely to be male (59.1% versus 53.2%; p<0.001), currently smoking (54.9% versus 47.6%; p<0.001) and from an ethnic minority group (p<0.001). Undiagnosed COPD was associated with less forced expiratory volume in 1 s impairment (Global Initiative for Chronic Obstructive Lung Disease (GOLD) grades 1 and 2: 85.3% versus 68.4%; p<0.001) and lower symptom/exacerbation burden (GOLD A and B groups: 95.6% versus 77.9%; p<0.001) than those with known COPD. Multivariate analysis demonstrated that airflow obstruction was an independent risk factor for lung cancer risk on baseline LDCT (adjusted OR 2.74, 95% CI 1.73-4.34; p<0.001), with a high risk seen in those with undiagnosed COPD (adjusted OR 2.79, 95% CI 1.67-4.64; p<0.001).

CONCLUSIONS

Targeted case-finding within LCS detects high rates of undiagnosed symptomatic COPD in those most at risk. Individuals with undiagnosed COPD are at high risk for lung cancer.

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.

Incidence, management, and outcome of lung cancer in patients with long-term oxygen therapy

BACKGROUND

Here, we aimed to assess the specific features of lung cancer in patients with long-term oxygen therapy (LTOT), and compare their outcomes with patients suffering from lung cancer without LTOT.

METHODS

This retrospective, case-controlled study included patients with LTOT and an incident diagnosis of lung cancer treated at Rouen University Hospital.

RESULTS

Out of 2201 patients with LTOT, 31 were diagnosed with lung cancer. Among 24 patients with proven lung cancer, the most frequent histological type was squamous cell carcinoma (n = 12/24, 50%). Active treatment of any type was given in 19/31 (61%) and 41/62 (66%) of patients in the LTOT and control groups, respectively (p = 0.83). In the LTOT group, median survival was 38 days with best supportive care and 462 days with active treatment (p = 0.003). However, when adjusting on performance status and disease stage, LTOT was not significantly associated with a worse outcome. Hazard ratio (HR): 1.56 (95% confidence interval [CI]: 0.87 to 2.81) (p = 0.137). Administration of any treatment was associated with a better prognostic: HR: 0.35 (95% CI: 0.19 to 0.66). Both groups had a similar treatment safety profile.

CONCLUSION

Incidence of lung cancer in patients with LTOT was comparable to the general population. The proportion of LTOT patients who received active treatment was similar to controls, and overall survival did not differ from controls in a multivariate analysis. Although reaching a histological diagnosis may be challenging in LTOT patients, the efficacy and safety of the management strategies of lung cancer seem preserved.

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.

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.

A Challenge for Emphysema Quantification Using a Deep Learning Algorithm With Low-dose Chest Computed Tomography

PURPOSE

We aimed to identify clinically relevant deep learning algorithms for emphysema quantification using low-dose chest computed tomography (LDCT) through an invitation-based competition.

MATERIALS AND METHODS

The Korean Society of Imaging Informatics in Medicine (KSIIM) organized a challenge for emphysema quantification between November 24, 2020 and January 26, 2021. Seven invited research teams participated in this challenge. In total, 558 pairs of computed tomography (CT) scans (468 pairs for the training set, and 90 pairs for the test set) from 9 hospitals were collected retrospectively or prospectively. CT acquisition followed the hospitals' protocols to reflect the real-world clinical setting. Using the training set, each team developed an algorithm that generated converted LDCT by changing the pixel values of LDCT to simulate those of standard-dose CT (SDCT). The agreement between SDCT and LDCT was evaluated using the intraclass correlation coefficient (ICC; 2-way random effects, absolute agreement, and single rater) for the percentage of low-attenuated area below -950 HU (LAA-950 HU), κ value for emphysema categorization (LAA-950 HU, <5%, 5% to 10%, and ≥10%) and cosine similarity of LAA-950 HU.

RESULTS

The mean LAA-950 HU of the test set was 14.2%±10.5% for SDCT, 25.4%±10.2% for unconverted LDCT, and 12.9%±10.4%, 11.7%±10.8%, and 12.4%±10.5% for converted LDCT (top 3 teams). The agreement between the SDCT and converted LDCT of the first-place team was 0.94 (95% confidence interval: 0.90, 0.97) for ICC, 0.71 (95% confidence interval: 0.58, 0.84) for categorical agreement, and 0.97 (interquartile range: 0.94 to 0.99) for cosine similarity.

CONCLUSIONS

Emphysema quantification with LDCT was feasible through deep learning-based CT conversion strategies.

Association between visual emphysema and lung nodules on low-dose CT scan in a Chinese Lung Cancer Screening Program (Nelcin-B3)

OBJECTIVES

This study aimed to evaluate the association between visual emphysema and the presence of lung nodules, and Lung-RADS category with low-dose CT (LDCT).

METHODS

Baseline LDCT scans of 1162 participants from a lung cancer screening study (Nelcin-B3) performed in a Chinese general population were included. The presence, subtypes, and severity of emphysema (at least trace) were visually assessed by one radiologist. The presence, size, and classification of non-calcified lung nodules (≥ 30 mm³) and Lung-RADS category were independently assessed by another two radiologists. Multivariable logistic regression and stratified analyses were performed to estimate the association between emphysema and lung nodules, Lung-RADS category, after adjusting for age, sex, BMI, smoking status, pack-years, and passive smoking.

RESULTS

Emphysema and lung nodules were observed in 674 (58.0%) and 424 (36.5%) participants, respectively. Participants with emphysema had a 71% increased risk of having lung nodules (adjusted odds ratios, aOR: 1.71, 95% CI: 1.26-2.31) and 70% increased risk of positive Lung-RADS category (aOR: 1.70, 95% CI: 1.09-2.66) than those without emphysema. Participants with paraseptal emphysema (n = 47, 4.0%) were at a higher risk for lung nodules than those with centrilobular emphysema (CLE) (aOR: 2.43, 95% CI: 1.32-4.50 and aOR: 1.60, 95% CI: 1.23-2.09, respectively). Only CLE was associated with positive Lung-RADS category (p = 0.02). CLE severity was related to a higher risk of lung nodules (ranges aOR: 1.44-2.61, overall p < 0.01).

CONCLUSION

In a Chinese general population, visual emphysema based on LDCT is independently related to the presence of lung nodules (≥ 30 mm³) and specifically CLE subtype is related to positive Lung-RADS category. The risk of lung nodules increases with CLE severity.

KEY POINTS

• Participants with emphysema had an increased risk of having lung nodules, especially smokers. • Participants with PSE were at a higher risk for lung nodules than those with CLE, but nodules in participants with CLE had a higher risk of positive Lung-RADS category. • The risk of lung nodules increases with CLE severity.

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.

Lung cancer in recipients after lung transplant: single-centre experience and literature review

Introduction

Lung cancer is a major challenge facing modern medicine. It is the leading cause of cancer-related death in the USA. Little is known of the incidence, prevalence and disease characteristics in lung transplant recipients, a population unique in its vulnerability and exposure to carcinogenic risk factors. We aimed to elaborate these characteristics of lung cancer in our population through a retrospective cohort study.

Methods

We retrospectively reviewed our institution’s 8-year experience with lung transplantation and searched for patients with a post-transplant diagnosis of lung cancer, neoplasia or mass. We focused on patient demographics, indication for transplant, smoking history, stage at diagnosis, location of the tumour, length of time between transplant and diagnosis, the treatment offered and length of time from diagnosis to death or last follow-up. Descriptive statistics and survival analysis standard Kaplan-Meier method was conducted from the date of cancer diagnosis to death from all-cause mortality or last follow-up as of August 2021.

Results

We identified 24 patients with de novo lung cancer postlung transplant in 905 recipients. More patients with an underlying diagnosis of idiopathic pulmonary fibrosis developed lung cancer. Twenty-one patients were diagnosed with non-small cell lung cancer and three had small cell lung cancer. The remaining native lung was involved most in single lung recipients with 17 patients. Patients with a diagnosis of lung cancer had a mean survival of 17.6 months after diagnosis.

Discussion

The incidence rate of lung cancer in our cohort was higher than reported for smokers from the general population in previous studies. In this study, we compare our findings with available literature. We also explore screening strategies, treatment modalities, survival and postulated mechanisms for the development of lung cancer in lung transplant recipients.

Computed tomography on lung cancer screening is useful for adjuvant comorbidity diagnosis in developing countries

Purpose

The aim of this study was to analyse and quantify the prevalence of six comorbidities from lung cancer screening (LCS) on computed tomography (CT) scans of patients from developing countries.

Methods

For this retrospective study, low-dose CT scans (n=775) were examined from patients who underwent LCS in a tertiary hospital between 2016 and 2020. An age- and sex-matched control group was obtained for comparison (n=370). Using the software, coronary artery calcification (CAC), the skeletal muscle area, interstitial lung abnormalities, emphysema, osteoporosis and hepatic steatosis were accessed. Clinical characteristics of each participant were identified. A t-test and Chi-squared test were used to examine differences between these values. Interclass correlation coefficients (ICCs) and interobserver agreement (assessed by calculating kappa coefficients) were calculated to assess the correlation of measures interpreted by two observers. p-values <0.05 were considered significant.

Results

One or more comorbidities were identified in 86.6% of the patients and in 40% of the controls. The most prevalent comorbidity was osteoporosis, present in 44.2% of patients and in 24.8% of controls. New diagnoses of cardiovascular disease, emphysema and osteoporosis were made in 25%, 7% and 46% of cases, respectively. The kappa coefficient for CAC was 0.906 (p<0.001). ICCs for measures of liver, spleen and bone density were 0.88, 0.93 and 0.96, respectively (p<0.001).

Conclusions

CT data acquired during LCS led to the identification of previously undiagnosed comorbidities. The LCS is useful to facilitate comorbidity diagnosis in developing countries, providing opportunities for its prevention and treatment.

Lung cancer screening is useful to facilitate comorbidity diagnosis in developing countries, providing opportunities for its prevention and treatmenthttps://bit.ly/3KEdGuW

Chest CT-assessed comorbidities and all-cause mortality risk in COPD patients in the BODE cohort

BACKGROUND AND OBJECTIVE

The availability of chest computed tomography (CT) imaging can help diagnose comorbidities associated with chronic obstructive pulmonary disease (COPD). Their systematic identification and relationship with all-cause mortality have not been explored. Furthermore, whether their CT-detected prevalence differs from clinical diagnosis is unknown.

METHODS

The prevalence of 10 CT-assessed comorbidities was retrospectively determined at baseline in 379 patients (71% men) with mild to severe COPD attending pulmonary clinics. Anthropometrics, smoking history, dyspnoea, lung function, exercise capacity, BODE (BMI, Obstruction, Dyspnoea and Exercise capacity) index and exacerbations rate were recorded. The prevalence of CT-determined comorbidities was compared with that recorded clinically. Over a median of 78 months of observation, the independent association with all-cause mortality was analysed. A 'CT-comorbidome' graphically expressed the strength of their association with mortality risk.

RESULTS

Coronary artery calcification, emphysema and bronchiectasis were the most prevalent comorbidities (79.8%, 62.7% and 33.9%, respectively). All were underdiagnosed before CT. Coronary artery calcium (hazard ratio [HR] 2.09; 95% CI 1.03-4.26, p = 0.042), bronchiectasis (HR 2.12; 95% CI 1.05-4.26, p = 0.036) and low psoas muscle density (HR 2.61; 95% CI 1.23-5.57, p = 0.010) were independently associated with all-cause mortality and helped define the 'CT-comorbidome'.

CONCLUSION

This study of COPD patients shows that systematic detection of 10 CT-diagnosed comorbidities, most of which were not detected clinically, provides information of potential use to patients and clinicians caring for them.

The Predictive Value of Stair Climbing Test on Postoperative Complications in Lung Cancer Patients with Limited Pulmonary Function

PURPOSE

To evaluate the predictive value of stair climbing test (SCT) on postoperative complications in lung cancer patients with limited pulmonary function.

METHODS

A total of 727 hospitalized lung cancer patients with limited pulmonary function were retrospectively reviewed. Included in the cohort were 424 patients who underwent SCT preoperatively. Patients were grouped according to general condition, past medical history, surgical approach, pulmonary function test, and SCT results. Comparison of the postoperative cardiopulmonary complication rates was made and independent risk factors were identified.

RESULTS

A total of 89 cardiopulmonary-related complications occurred in 69 cases, accounting for 16.3% of the entire cohort. The postoperative cardiopulmonary complication rates were significantly different between groups stratified by smoking index, percentage of forced expiratory volume in one second, percentage of diffusion capacity for carbon monoxide, SCT results, excision extension, and anesthetic duration (p <0.05). Multivariate analysis showed that only height achieved (p <0.001), changes in heart rate (∆HR; p <0.001), and excision extension (p = 0.006) were independent risk factors for postoperative cardiopulmonary complications.

CONCLUSIONS

The SCT could be used as a preoperative screening method for lung cancer patients with limited pulmonary function. For those patients who could only climb less than 6 floors or had ∆HR >30 bpm in the test, sublobar resection should be selected to reduce the postoperative cardiopulmonary complication rate.

[Lung Cancer Surgery for Severe COPD with Emphysema: Tumor Resection with Improvement of Lung Function]

Lung Cancer Surgery for Severe COPD with Emphysema: Tumor Resection with Improvement of Lung Function Abstract. The golden standard for the therapy of early stage non-small cell lung cancer consists of surgical resection, usually performed as lobectomy or segmentectomy. These procedures demand a certain operability, including certain lung functional reserves. Patients with COPD and emphysema usually have lung function values far below that. Nevertheless, these patients can be offered treatmentif at the same time they qualify for concomitant lung volume reduction surgery (LVRS). LVRS with simultaneous tumor resection can consolidate the diagnosis, provide definite histology, correct staging, and thorough tumor resection might even improve the postoperative lung function. As with all patients with a (possible) diagnosis of cancer, the indication must be discussed in an interdiscplinary tumor board.

Pulmonary Emphysema Regional Distribution and Extent Assessed by Chest Computed Tomography Is Associated With Pulmonary Function Impairment in Patients With COPD

Objective: This study aimed to evaluate how emphysema extent and its regional distribution quantified by chest CT are associated with clinical and functional severity in patients with chronic obstructive pulmonary disease (COPD). Methods/Design: Patients with a post-bronchodilator forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) < 0.70, without any other obstructive airway disease, who presented radiological evidence of emphysema on visual CT inspection were retrospectively enrolled. A Quantitative Lung Imaging (QUALI) system automatically quantified the volume of pulmonary emphysema and adjusted this volume to the measured (EmphCTLV) or predicted total lung volume (TLV) (EmphPLV) and assessed its regional distribution based on an artificial neural network (ANN) trained for this purpose. Additionally, the percentage of lung volume occupied by low-attenuation areas (LAA) was computed by dividing the total volume of regions with attenuation lower or equal to -950 Hounsfield units (HU) by the predicted [LAA (%PLV)] or measured CT lung volume [LAA (%CTLV)]. The LAA was then compared with the QUALI emphysema estimations. The association between emphysema extension and its regional distribution with pulmonary function impairment was then assessed. Results: In this study, 86 patients fulfilled the inclusion criteria. Both EmphCTLV and EmphPLV were significantly lower than the LAA indices independently of emphysema severity. CT-derived TLV significantly increased with emphysema severity (from 6,143 ± 1,295 up to 7,659 ± 1,264 ml from mild to very severe emphysema, p < 0.005) and thus, both EmphCTLV and LAA significantly underestimated emphysema extent when compared with those values adjusted to the predicted lung volume. All CT-derived emphysema indices presented moderate to strong correlations with residual volume (RV) (with correlations ranging from 0.61 to 0.66), total lung capacity (TLC) (from 0.51 to 0.59), and FEV1 (~0.6) and diffusing capacity for carbon monoxide DLCO (~0.6). The values of FEV1 and DLCO were significantly lower, and RV (p < 0.001) and TLC (p < 0.001) were significantly higher with the increasing emphysema extent and when emphysematous areas homogeneously affected the lungs. Conclusions: Emphysema volume must be referred to the predicted and not to the measured lung volume when assessing the CT-derived emphysema extension. Pulmonary function impairment was greater in patients with higher emphysema volumes and with a more homogeneous emphysema distribution. Further studies are still necessary to assess the significance of CTpLV in the clinical and research fields.

Comorbidities Associated With Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease or COPD is characterized by airflow obstruction, causing respiratory symptoms. There are treatments available for COPD; however, COPD has significant extrapulmonary effects, including well-recognized ones as cardiovascular disease and often underdiagnosed ones as osteoporosis. It is imperative to be aware of these comorbidities to optimize COPD patient care.

Tumor size in patients with severe pulmonary emphysema might be underestimated on preoperative CT

OBJECTIVES

To evaluate the effect of emphysema on tumor diameter measured on preoperative computed tomography (CT) images versus pathological specimens.

MATERIALS AND METHODS

We investigated patients who underwent primary lung cancer surgery: 55 patients (57 tumors) with severe emphysema and 57 patients (57 tumors) without emphysema. The tumor diameters measured in the postoperative pathological specimens were compared with those measured on the axial CT images and on multiplanar reconstruction (MPR) CT images by two independent radiologists; a subgroup analysis according to tumor size was also performed. A paired or unpaired t test was performed, depending on the tested subjects.

RESULTS

In the emphysema group, the mean axial CT diameter was significantly smaller than the mean pathological diameter (p = 0.025/0.001 for reader 1/2), whereas in the non-emphysema group, the mean axial CT diameter was not significantly different from the pathological one for both readers. The difference between CT axial diameter and pathological diameter (= CT diameter - pathological diameter) was significantly smaller (i.e., had a stronger tendency toward underestimation on radiological measurements) in the emphysema group compared with the non-emphysema group (p = 0.014/0.008 for reader 1/2), and the difference was significantly smaller in tumors sized > 30 mm than tumors sized ≤ 20 mm in both groups.

CONCLUSIONS

Tumor size is significantly smaller on preoperative CT in patients with severe emphysema compared to patients without emphysema, especially in the case of large tumors. MPR measurement using the widest of three dimensions should be used to select T-stage for patients with severe emphysema.

KEY POINTS

• The presence of emphysema affects the accuracy of tumor size measurements on CT. • Compared to patients without emphysema, the tumor size in severe emphysema patients tends to be measured smaller in preoperative CT than the pathological specimen. • This trend is more evident when large tumors are measured on axial CT images alone.

Video-assisted thoracoscopic surgery for primary lung cancer resections in patients with moderate to severe chronic obstructive pulmonary diseases

Background

Lung cancer patients with chronic obstructive pulmonary disease (COPD) are considered a high-risk population to receive radical surgical treatment due to the high incidence of cardiopulmonary complications. The aim of this study was to evaluate the clinical factors associated with postoperative complications in primary lung cancer patients with moderate to extremely severe grades of COPD.

Methods

From December 2015 to June 2020, 138 patients with moderate to extremely severe COPD who underwent video-assisted thoracoscopic surgery (VATS) lung cancer resection (lobectomy or sublobar resection) were retrospectively reviewed. Patients' postoperative complications were collected from clinical records. Clinical factors (such as COPD severity or surgical approaches, etc.) were evaluated to investigate the association with postoperative complications.

Results

Of the 138 patients included in the study, the mean age was 67 (63-74) years, the mean preoperative forced expiratory volume in one second (FEV1) was 1.33±0.39 L, the mean FEV1% was 51.23% (41.43-60.00%). 33% patients (46/138) had postoperative complications, and no mortality occurred. Univariate analysis revealed that incidence of overall complications (OCs) and respiratory complications (RCs) was markedly higher in extremely severe COPD patients compared to moderate (OCs, P=0.033; RCs, P=0.050) and severe (OCs, P=0.015; RCs, P=0.008) COPD patients, respectively. Multivariate analysis showed that COPD grade was an independent risk factor of RCs (P=0.024). Furthermore, the grades of COPD (moderate, P=0.029; severe, P=0.028; extremely severe, P=0.019) and the surgical procedure (lobectomy or sublobar resection, P=0.043) were independent risk factors for atelectasis, which was the most common postoperative complication.

Conclusions

The aggravation of COPD was accompanied by an increase in the incidence of respiratory system complications postoperatively, especially atelectasis. For patients with moderate to extremely severe grades of COPD, careful perioperative evaluation should be performed to identify the indicators that influence the surgical choice between lobectomy and sublobar resection.

Towards Rational Prescription of Common Inhaler Medication in the Multimorbid COPD Patient

COPD is a chronic disease, typically accompanied by multiple comorbid conditions. The need to apply several, and sometimes conflicting, disease-specific treatment guidelines, complicates the management of individual patients. Moreover, national and international recommendations evolve rapidly but provide limited guidance on the integrated approach in the multimorbid patient. Particularly bothersome is the fact that the presence of comorbidities may deteriorate the course of COPD, and inversely COPD may affect the outcome of the comorbid diseases. In addition, some effects of commonly prescribed COPD inhaler medications, including beta2-agonists, long-acting antimuscarinics and especially inhaled corticosteroids, mimic or worsen COPD-related comorbidities. Therefore, the authors combined their perspectives to formulate advice that may help physicians to improve COPD patient care in daily practice when comorbidities are present. Diabetes, atrial fibrillation, osteoporosis/fractures, infections (pneumonia and tuberculosis) and asthma were identified as areas where practicing clinicians should give special attention to the risk-benefit ratio of the inhaled medication. Overall, the presence of multimorbidity in a COPD patient should act as a signal to carefully reconsider the treatment choices.

Use of carbon nanotube sensor for detecting postoperative abnormal respiratory waveforms

Background

This feasibility study aimed to detect respiratory waveforms from thoracic movements and evaluate if postoperative complications could be predicted using a carbon nanotube sensor.

Methods

Fifty patients who underwent lung resection for lung tumors were enrolled. The lung monitoring system of the carbon nanotube sensor was placed on bilateral chest walls across the 6^th–9^th ribs to measure chest wall motion. We examined the respiratory waveform in relation to surgical findings, postoperative course, and complications using Hilbert transform and Fast Fourier Transform (FFT).

Results

Of 50 patients (37 males, 13 females), 22 were included in the normal lung function group and 28 were included in the low lung function group. The respiratory rate and waveform indicated a regular pattern in the normal lung function group and the respiratory rate could be detected. Conversely, irregular respiratory pattern was detected in 70% of patients in the low lung function group. There was no significant different overall envelope peak value between operated side and non-operated side (0.195±0.05 and 0.18±0.06). In contrast, there was significantly high peak value in the presence of postoperative complications (P<0.05). And there was a significantly higher peak value in air leakage presence than air leakage absence in operated side (P=0.045).

Conclusions

The present study confirmed the feasibility of the sensor. It is promising in visualizing the respiratory state and detecting respiratory changes postoperatively.

The Incidence and Risk Analysis of Lung Cancer Development in Patients with Chronic Obstructive Pulmonary Disease: Possible Effectiveness of Annual CT-Screening

Purpose

Lung cancer is a serious complication in patients with chronic obstructive pulmonary disease (COPD) and accounts for approximately 15% of deaths in patients with COPD. However, with the exception of emphysema, few reports to date have been published on the factors that predict lung cancer development in COPD patients. It has been reported that patients with COPD develop lung cancer at a rate of 0.8% - 1.7%/year, but the incidence may be higher in the Japanese population. Therefore, we investigated the incidence of lung cancer and the lung cancer mortality rate in Japanese COPD patients, as well as factors that are associated with the development of lung cancer in COPD patients.

Patients and Methods

We followed up 224 patients with stable COPD and performed CT examinations at least once per year. The incidence of lung cancer was recorded and data at enrollment were compared with data of the group that did not develop lung cancer.

Results

Over a median follow-up period of 4.58 years, lung cancer was newly diagnosed in 19 patients; the incidence of lung cancer in this population was 1.85%/year. Patients who developed lung cancer had more severe emphysema assessed by CT and GOLD classification and were more likely to be current smokers than those who did not develop lung cancer. No other significant differences were observed between these two groups. Mortality was significantly increased in patients who developed lung cancer compared with those who did not.

Conclusion

In COPD patients, the incidence of lung cancer is higher and the development of lung cancer worsens the prognosis; however, lung cancer development is unpredictable and attention should be paid to all patients. Annual CT screening is important for early detection of lung cancer.

The importance of low-dose CT screening to identify emphysema in asymptomatic participants with and without a prior diagnosis of COPD

PURPOSE

Chronic Obstructive Pulmonary Disease (COPD) includes chronic bronchitis, small airways disease, and emphysema. Diagnosis of COPD requires spirometric evidence and may be normal even when small airways disease or emphysema is present. Emphysema increases the risk of exacerbations, and is associated with all-cause mortality and increased risk of lung cancer. We evaluated the prevalence of emphysema in participants with and without a prior history of COPD.

METHODS

We reviewed a prospective cohort of 52,726 subjects who underwent baseline low dose CT screening for lung cancer from 2003 to 2016 in the International Early Lung Cancer Action Program.

RESULTS

Of 52,726 participants, 23.8%(12,542) had CT evidence of emphysema. Of these 12,542 participants with emphysema, 76.5%(9595/12,542) had no prior COPD diagnosis even though 23.6% (2258/9595) had moderate or severe emphysema. Among 12,542 participants, significant predictors of no prior COPD diagnosis were: male (OR = 1.47, p < 0.0001), younger age (OR_age10 = 0.72, p < 0.0001), lower pack-years of smoking (OR_10pack-years = 0.90, p < 0.0001), completed college or higher (OR = 1.54, p < 0.0001), no family history of lung cancer (OR = 1.12, p = 0.04), no self-reported cardiac disease (OR = 0.76, p = 0.0003) or hypertension (OR = 0.74, p < 0.0001). The severity of emphysema was significantly lower among the 9595 participants with no prior COPD diagnosis, the OR for moderate emphysema was OR_moderate = 0.58(p = 0.0007) and for severe emphysema, it was OR_severe = 0.23(p < 0.0001).

CONCLUSION

Emphysema was identified in 23.8% participants undergoing LDCT and was unsuspected in 76.5%. LDCT provides an opportunity to identify emphysema, and recommend smoking cessation.