[Asbestos: detection and characterization in tissue]

BACKGROUND

When asbestos fibers are inhaled, asbestos bodies can form in the lungs with the involvement of macrophages. It can take decades from the last exposure to the onset of an asbestos-related disease.

OBJECTIVES

The aim of this review is to present methods to detect asbestos bodies in lung tissue, the development of diagnostic criteria and to discuss pros and cons of different methods.

MATERIALS AND METHODS

Observations and evaluations from the German Mesothelioma Register, along with relevant literature review and expert recommendations in guidelines are presented.

RESULTS

Assessing asbestos-related diseases requires recognition of the person's occupational history, the asbestos fiber burden in the lungs, and determining fiber types. Various methods have been developed and validated, including light microscopy techniques such as bright-field microscopy, phase-contrast microscopy, polarization microscopy, and differential interference microscopy, as well as electron microscopy techniques like field-emission-scanning electron microscopy (e.g., FE-SEM) and transmission electron microscopy (TEM).

CONCLUSION

The use of asbestos has been heavily restricted worldwide, even completely banned in Europe. Thus, patients' exposure to asbestos is decreasing. However, asbestos exposure during renovations, demolitions, or through unconscious handling of asbestos-containing materials remains a concern.

Global, regional, and national burden of asbestosis from 1990 to 2019 and the implications for prevention and control

BACKGROUND

Asbestosis is a common pneumoconiosis caused by long-term asbestos exposure. Analysis of the burden of asbestosis would help in creating informed public health strategies.

METHODS

Data on asbestosis were analyzed using the Global Burden of Disease study 2019. The estimated annual percentage change (EAPC) was calculated to demonstrate temporal trends in the age-standardized rate (ASR) of asbestosis from 1990 to 2019.

RESULTS

Globally, 36,339 incident cases of asbestosis, led to 3572 deaths and 71,225 disability adjusted life years (DALYs) in 2019. During 1990-2019, the overall ASRs of incidence and DALYs declined by an annual average of 0.29 % and 0.27 %, with the respective EAPCs being -0.29 (95 % confidence interval [CI]: -0.43, -0.14) and -0.27 (95%CI: -0.53, -0.01). The ASRs of mortality increased with EAPC of 0.65 (95%CI: 0.34, 0.96). Trends in incidence and prevalence rose in females, but declined in males. The asbestosis burden was heterogeneous across regions and countries. The heaviest burden of asbestosis was observed in the United States, India, and China. Trends in ASRs of asbestosis varied across countries/territories. Pronounced increasing trends in incidence and prevalence occurred in Georgia, Iran, and Croatia.

CONCLUSIONS

Decreasing incident trend of asbestosis was observed globally over the past three decades. However, the ongoing asbestosis burden highlighted that asbestosis remained a challenge to public health, and cost-effective measures were required to reduce the asbestosis burden.

Epidemiology of Asbestosis between 2010-2014 and 2015-2019 Periods in Colombia: Descriptive Study

Background

Asbestosis is a prevalent worldwide problem, but scarce data sourced from developing countries are available. We describe the sociodemographic characteristics and patterns in the occurrence of care provided for asbestosis in Colombia during the periods 2010-2014 and 2015-2019 to establish the behavior, trends, and variables associated with concentrations among people attended by asbestosis.

Methods

A retrospective descriptive study was carried out with data from the Integrated Social Protection Information System (SISPRO) for two 5-year periods. People attended by asbestosis (ICD-10: J61) were identified; the frequency of patient visits, sociodemographic characteristics, case distribution patterns, and trends in both five-year periods were described, as was the crude frequency (cFr, 95% CI) of asbestosis (1,000,000 people/year) in both five-year periods (cFr ratio, 95% CI).

Results

During the period 2010-2019, 765 people attended by asbestosis were identified; there were 308 people attended by asbestosis between 2010-2014 (cFr: 2.20, 1.96-2.47), and ther were 457 people attended by asbestos between 2015-2019 (cFr: 3.14, 2.92-3.50). In both periods, the estimated cFr in men was nine times the estimated cFr in women. The cFr increased in the 2015-2019 period (cFr_ratio: 1.23, 1.06-1.43). Compared with the 2010-2014 period, the cFr of asbestosis increased in women (cFr_ratio: 1.44, 1.03-2.01), in the Andean (cFr_ratio: 1.61, 1.35-1.95) and Caribbean regions (cFr_ratio: 1. 66, 1.21-2.30), in the urban area (cFr_ratio: 1.24, 1.05-1.48), and in the age groups 45-59 years (cFr_ratio: 1.34, 1.001-1.79) and ≥60 years (cFr_ratio: 1.43, 1.13-1.83).

Discussion

During two five-year periods, the cFr of asbestosis was higher in men; between the first and second five-year periods, it increased significantly, especially in urbanized geographic areas and in populations aged ≥45 years. The estimates possibly reflect the effect of disease latency or the expected impact of public health policies to monitor asbestos exposure and complications.

Occupational Lung Diseases: Spectrum of Common Imaging Manifestations

Occupational lung diseases (OLD) are a group of preventable conditions caused by noxious inhalation exposure in the workplace. Workers in various industries are at a higher risk of developing OLD. Despite regulations contributing to a decreased incidence, OLD remain among the most frequently diagnosed work-related conditions, contributing to significant morbidity and mortality. A multidisciplinary discussion (MDD) is necessary for a timely diagnosis. Imaging, particularly computed tomography, plays a central role in diagnosing OLD and excluding other inhalational lung diseases. OLD can be broadly classified into fibrotic and non-fibrotic forms. Imaging reflects variable degrees of inflammation and fibrosis involving the airways, parenchyma, and pleura. Common manifestations include classical pneumoconioses, chronic granulomatous diseases (CGD), and small and large airway diseases. Imaging is influenced by the type of inciting exposure. The findings of airway disease may be subtle or solely uncovered upon expiration. High-resolution chest CT, including expiratory-phase imaging, should be performed in all patients with suspected OLD. Radiologists should familiarize themselves with these imaging features to improve diagnostic accuracy.

Sustainable management of hazardous asbestos-containing materials: Containment, stabilization and inertization

Asbestos is a group of six major silicate minerals that belong to the serpentine and amphibole families, and include chrysotile, amosite, crocidolite, anthophyllite, tremolite and actinolite. Weathering and human disturbance of asbestos-containing materials (ACMs) can lead to the emission of asbestos dust, and the inhalation of respirable asbestos fibrous dust can lead to 'mesothelioma' cancer and other diseases, including the progressive lung disease called 'asbestosis'. There is a considerable legacy of in-situ ACMs in the built environment, and it is not practically or economically possible to safely remove ACMs from the built environment. The aim of the review is to examine the three approaches used for the sustainable management of hazardous ACMs in the built environment: containment, stabilization, and inertization or destruction. Most of the asbestos remaining in the built environment can be contained in a physically secured form so that it does not present a significant health risk of emitting toxic airborne fibres. In settings where safe removal is not practically feasible, stabilization and encapsulation can provide a promising solution, especially in areas where ACMs are exposed to weathering or disturbance. Complete destruction and inertization of asbestos can be achieved by thermal decomposition using plasma and microwave radiation. Bioremediation and chemical treatment (e.g., ultrasound with oxalic acid) have been found to be effective in the inertization of ACMs. Technologies that achieve complete destruction of ACMs are found to be attractive because the treated products can be recycled or safely disposed of in landfills.

Expression of microRNAs in leukocytes and serum of asbestosis patients

BACKGROUND

Although asbestos use is banned in many countries, long latency of asbestos-related diseases like pleural plaques or asbestosis mean it is still a public health issue. People suffering from these diseases have a higher risk of developing mesothelioma or lung cancer, which can progress quickly and aggressively. MicroRNAs were suggested as potential biomarkers in several diseases. However, in asbestosis, blood microRNAs are less explored. Since miR-32-5p, miR-143-3p, miR-145-5p, miR-146b-5p, miR-204-5p and miR-451a are involved in fibrotic processes and in cancer, expression of these microRNAs was analyzed in leukocytes and serum of asbestosis patients.

METHODS

MicroRNA expression was analyzed in leukocytes and serum of 36 patients (26 affected by pleural plaques and 10 by asbestosis) and 15 healthy controls by real-time RT-PCR. Additionally, data analyses were performed regarding disease severity based on ILO classification.

RESULTS

MicroRNA miR-146b-5p was significantly down-regulated in leukocytes of patients suffering from pleural plaques with a large effect indicated by η²_p = 0.150 and Cohen's f = 0.42, a value of difference of 0.725 and a 95% confidence interval of 0.070-1.381. In patients suffering from asbestosis miR-146b-5p was not significantly regulated. However, data analyses considering disease severity only, revealed that miR-146b-5p was significantly down-regulated in leukocytes of mildly diseased patients compared to controls with a large effect indicated by η²_p = 0.178 and Cohen's f = 0.465, a value of difference of 0.848 and a 95% confidence interval of 0.097-1.599. Receiver operating characteristic (ROC) curve and an area under the ROC curve value of 0.757 for miR-146b-5p indicated acceptable discrimination ability between patients suffering from pleural plaques and healthy controls. Less microRNAs were detectable in serum than in leukocytes, showing no significant expression differences in all participants of this study. Moreover, miR-145-5p was regulated significantly differently in leukocytes and serum. An R² value of 0.004 for miR-145-5p indicated no correlation in microRNA expression between leukocytes and serum.

CONCLUSION

Leukocytes seem more suitable than serum for microRNA analyses regarding disease and potentially cancer risk assessment of patients suffering from asbestos-related pleural plaques or asbestosis. Long-term studies may reveal whether down-regulation of miR-146b-5p in leukocytes might be an early indicator for an increased cancer risk.

Genetic susceptibility in pneumoconiosis in China: a systematic review

OBJECTIVE

Pneumoconiosis, encompassing coal workers' pneumoconiosis (CWP), silicosis and asbestosis, is one of the most common occupational diseases in China. Previous studies revealed significant associations between genetic variations and pneumoconiosis risk among individuals in different countries. With the known variability of genetic makeup between ethnicities, susceptibility to pneumoconiosis due to genetic differences is likely to be ethnicity-specific. The present review aimed at providing a comprehensive overview on the association between genetic polymorphisms and susceptibility of pneumoconiosis, specifically among people in China.

METHODS

The literature search was performed in seven English and Chinese databases using keywords related to the review aim. An appraisal of the methodological quality of the included studies was conducted using the assessment tool derived from the Strengthening the Reporting of Genetic Association Studies (STREGA) statement.

RESULTS

Forty-five studies were included in this review. Genotypes of specific genes which are associated with the risk of CWP, silicosis and asbestosis were reported. Our findings showed that genes encoding inflammatory cytokines have been examined extensively, and they demonstrated an association between these genes and pneumoconiosis risk. Gene-environment interactions in pneumoconiosis susceptibility were also reported by a number of studies.

CONCLUSIONS

This review summarised the evidence demonstrating the association between genetic polymorphisms and pneumoconiosis susceptibility among people in China, and that various genotypes could modify their risk to develop pneumoconiosis. The findings prompt that identification of individuals at high pneumoconiosis risk through genetic screening and strategies limiting their exposure to dust could be a potential strategy for the control of this occupational disease in China.

Artificial intelligence-based diagnosis of asbestosis: analysis of a database with applicants for asbestosis state aid

OBJECTIVES

In many countries, workers who developed asbestosis due to their occupation are eligible for government support. Based on the results of clinical examination, a team of pulmonologists determine the eligibility of patients to these programs. In this Dutch cohort study, we aim to demonstrate the potential role of an artificial intelligence (AI)-based system for automated, standardized, and cost-effective evaluation of applications for asbestosis patients.

METHODS

A dataset of n = 523 suspected asbestosis cases/applications from across the Netherlands was retrospectively collected. Each case/application was reviewed, and based on the criteria, a panel of three pulmonologists would determine eligibility for government support. An AI system is proposed, which uses thoracic CT images as input, and predicts the assessment of the clinical panel. Alongside imaging, we evaluated the added value of lung function parameters.

RESULTS

The proposed AI algorithm reached an AUC of 0.87 (p < 0.001) in the prediction of accepted versus rejected applications. Diffusion capacity (DLCO) also showed comparable predictive value (AUC = 0.85, p < 0.001), with little correlation between the two parameters (r-squared = 0.22, p < 0.001). The combination of the imaging AI score and DLCO achieved superior performance (AUC = 0.95, p < 0.001). Interobserver variability between pulmonologists on the panel was estimated at alpha = 0.65 (Krippendorff's alpha).

CONCLUSION

We developed an AI system to support the clinical decision-making process for the application to the government support for asbestosis. A multicenter prospective validation study is currently ongoing to examine the added value and reliability of this system alongside the clinic panel.

KEY POINTS

• Artificial intelligence can detect imaging patterns of asbestosis in CT scans in a cohort of patients applying for state aid. • Combining the AI prediction with the diffusing lung function parameter reaches the highest diagnostic performance. • Specific cases with fibrosis but no asbestosis were correctly classified, suggesting robustness of the AI system, which is currently under prospective validation.

Restrictions of VC and DLCO in relation to asbestos-related computed tomographic findings quantified by ICOERD-based parameters

BACKGROUND

Even almost 30 years after the ban on the use of asbestos in Germany, the effects of asbestos are still highly relevant in everyday clinical practice in occupational medicine. The aim of this study was to further investigate the significance of essential parameters of both pulmonary function diagnostics and imaging techniques (low-dose HR-TCT) for the prevention and early detection of asbestos-related morphological and functional lung changes.

METHODS

Data from spirometry, body plethysmography and diffusion capacity, as well as CT images of the thorax, were retrospectively studied from 72 patients examined between 2017 and 2019 at the Institute for Occupational and Maritime Medicine (ZfAM), Hamburg, Germany. The subjects were divided into four subgroups according to the presence of comorbidities (concomitant cardiac diseases, obstructive ventilatory disorder, pulmonary function pattern consistent with emphysema, and no other pulmonary or cardiac diseases). These subgroups were analysed in addition to the overall collective. The CT images were evaluated according to the International Classification of Occupational and Environmental Respiratory Diseases (ICOERD) with radiological expertise. In addition, some asbestos-related parameters were newly quantified, and corresponding scores were defined based on ICOERD. Statistical analysis included the use of correlations and fourfold tables with calculation of Spearman's rho (ρ), Cohen's κ, and accuracy.

RESULTS

Vital capacity (VC) is slightly reduced in the total collective compared to the normal population (mean 92% of predicted value), while diffusion capacity for CO (DLCO) shows predominantly pathological values, mean 70% of the respective predicted value. The CO transfer coefficient (DLCO/VA), which refers to alveolar volume (VA), also shows slightly decreased values (mean 87% pred.). Seventy-nine percent of patients (n = 57) had signs of pulmonary fibrosis on CT scans, and pleural plaques appeared in 58 of 72 patients (81%). Of the newly quantified additional parameters, particularly frequently described findings are subpleural curvilinear lines (SC, n = 39) and parenchymal bands (PB, n = 29). VC correlates well with the expression of pleural plaques (ρ = - 0.273, P < 0.05), and DLCO measures show a better correlation with fibrosis score (ρ = - 0.315, P < 0.01). A third, newly developed score, which includes the extent of pleural plaques and additional subpleural parameters instead of fibrosis parameters, shows significant correlations for both VC and DLCO (ρ = - 0.283, - 0.274, resp.; both P < 0.05).

DISCUSSION

The importance of spirometry (VC) and diffusion capacity measurement (DLCO) as essential diagnostic procedures for the early detection of asbestos-related changes ‒ also including patients with relevant concomitant cardiac or pulmonary diseases ‒ was confirmed. Significant and better correlations between lung function changes (VC and DLCO) and abnormal CT findings are seen when parenchymal bands (PB), subpleural curvilinear lines (SC), and rounded atelectasis (RA) are quantitatively included into the evaluation, in addition to assessing the extent of pleural plaques alone. Therefore, when assessing CT images according to ICOERD, these parameters should also be quantified.

High-resolution computed tomography features of asbestosis versus fibrotic hypersensitivity pneumonitis: an observational study

Background

Asbestosis and fibrotic hypersensitivity pneumonitis (FHP) share the pathogenetic mechanisms induced bronchiolocentric fibrotic process secondary to inhalation exposure. Under the occupational and environmental mixed exposures, asbestosis and FHP are needed to make the differential diagnoses on high-resolution computed tomography (HRCT), especially in the countries still using asbestos. The study aimed to analyze the HRCT features of asbestosis versus FHP.

Methods

The patients with asbestosis or with HP were sequentially recruited in this comparative study at Beijing Chaoyang Hospital between January 2006 and December 2016. Patients’ clinical data were obtained from a predesigned charts. The international classification of HRCT for occupational and environmental respiratory diseases was used to categorize chest imaging findings in patients. The calculation of test statistics was used to compare the imaging features of asbestosis and FHP.

Results

341 patients with asbestosis and 158 patients with HP were sequentially recruited, among which 204 patients with asbestosis and 74 patients with FHP were eligible for data analysis. Patients with asbestosis were older and had a longer latent period until disease manifestation than those with FHP. Asbestosis was characterized by irregular and/or linear opacities, with lower lung preponderance, accompanied by ground-glass opacities and mosaic attenuation. Notably, 98.5% of patients with asbestosis showed benign pleural abnormalities, and 39.7% of these patients had diffuse pleural thickening with parenchymal bands and/or rounded atelectasis. Abnormalities of the mediastinal and diaphragmatic pleura were observed only in cases of asbestosis, and this finding showed high specificity for the diagnosis for asbestosis compared with that for FHP. Subpleural dots or diaphragmatic pleural abnormalities showed moderate sensitivity and high specificity for diagnosis of asbestosis compared with that for FHP. Interobserver reliability was good for evaluation of imaging findings including honeycombing, pleural calcification, lymphadenectasis, and lymph node calcification.

Conclusions

HRCT-based imaging findings can distinguish between asbestosis and FHP to a certain extent, particularly with regard to subpleural dots and diaphragmatic pleural abnormalities that characterize the former.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01967-3.

[Chest high-resolution CT features analysis in predicting the progression of asbestosis]

Objective: To analyze the radiological characteristics of chest high-resolution computed tomography (HRCT) of patients with asbestosis, and to investigate the signs of predicting the disease progression of asbestosis. Methods: A prospective method was used to enroll 68 patients with asbestosis who were regularly followed up from 2013 to 2016. The radiological characteristics of patients with asbestosis were described by the International Classification of HRCT for Occupational and Environmental Respiratory Diseases (ICOERD) , and the differences between patients with and without progression were compared during the observation period. The Cox proportional hazards regression model was used to analyze the chest HRCT radiological signs predicting the progression of asbestosis. Results: The study included 68 patients with asbestosis aged (65.5±7.8) years old, of which 64.7% (44/68) were female, 29.4% (20/68) had a history of smoking. There was no significant difference in age, sex, smoking and asbestos exposure between patients with progressive asbestosis (20.6%, 14/68) and patients without progressive asbestosis (79.4%, 54/68) (P>0.05) . Chest HRCT of patients with asbestosis showed irregular and/or linear opacities, of which 5.9% (4/68) were accompanied by honeycombing. Irregular and/or linear opacities were mainly lower lung preponderant, often accompanied with ground glass opacity and mosaic perfusion. 98.5% (67/68) had pleural abnormalities, of which 39.7% (27/68) had diffuse pleural thickening with parenchymal bands and/or rounded atelectasis. The analysis of multivariable Cox proportional hazard regression showed that the risk of the progression of asbestosis was increased with higher irregular and/or linears opacities cores (HR=1.184, 95%CI: 1.012-1.384, P=0.034) and the appearance of honeycombing (HR=6.488, 95%CI: 1.447-29.097, P=0.015) . Conclusion: The irregular and/or linear opacities scores and honeycombing on chest HRCT are independent influencing factors for predicting the disease progression of asbestosis.

Asbestosis diagnosis algorithm combining the lung segmentation method and deep learning model in computed tomography image

BACKGROUND

Early detection of asbestosis is important; hence, quick and accurate diagnostic tools are essential. This study aimed to develop an algorithm that combines lung segmentation and deep learning models that can be utilized as a clinical decision support system (CDSS) for diagnosing patients with asbestosis in segmented computed tomography (CT) images.

METHODS

We accurately segmented the lungs in CT images of patients examined at Seoul St. Mary's Hospital using a threshold-based method. Lungs with asbestosis and normal lungs were classified by applying the segmented image to the long-term recurrent convolutional network deep learning model. Performance was evaluated using the area under the receiver operating characteristic curve (AUROC) and F1 score from the test data.

RESULTS

The algorithm developed using the DenseNet201pre-trained model showed excellent performance, with a sensitivity of 0.962, specificity of 0.975, accuracy of 0.970, AUROC of 0.968, and F1 score of 0.961.

CONCLUSIONS

We developed an algorithm with significantly better diagnostic accuracy than a radiologist (0.970 vs. 0.73-0.79). Our developed algorithm is expected to be an excellent support tool if used as a CDSS to diagnose asbestosis using CT images.

Downregulation of the PD-1/PD-Ls pathway in peripheral cells correlates with asbestosis severity

Background

Asbestosis and silicosis are characterized by diffuse or nodular interstitial lung fibrosis resulting from exposure to asbestos or silica dust, respectively. This study was designed to detect programmed cell death protein (PD-1)/programmed death ligands (PD-Ls) expression in patients with asbestosis and silicosis and to explore the possible clinical significance of PD-1/PD-Ls expression in patients with the two diseases.

Methods

Thirty patients with asbestosis, 23 patients with silicosis and 25 healthy controls were consecutively recruited and provided informed consent to participate in the study. Clinical data were collected from patients’ clinical charts. PD-1/PD-Ls expression in peripheral blood (PB) was detected using flow cytometry.

Results

PD-1 was expressed at significantly lower levels on CD4⁺ or CD8⁺ peripheral T cells from patients with asbestosis and silicosis than on cells from healthy controls. Similarly, significantly lower PD-L1 and PD-L2 expression was detected on CD14⁺ monocytes from patients with asbestosis and silicosis than on cells from healthy controls. In addition, no significant differences in PD-1, PD-L1 and PD-L2 expression were observed between the asbestosis and silicosis groups. Moreover, the proportions of PD-1⁺ CD4⁺ T cells and PD-1⁺ CD8⁺ T cells in patients with asbestosis were positively correlated with the percentage of forced vital capacity predicted.

Conclusions

Decreased PD-1 expression on CD4⁺ T or CD8⁺ T cells in PB was positively correlated with the asbestosis severity, implying that pulmonary fibrosis development in patients with asbestosis was positively correlated with the downregulation of the PD-1/PD-Ls pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01531-5.

Occupational lung disease: A narrative review of lung conditions from the workplace

Occupational lung diseases are lung conditions caused or made worse by materials when a person is exposed to a workplace. The diagnosis of an occupational disease is important for workers' decision to continue work and for their eligibility under compensation programmes. We revisit the existing lung diseases that are closely associated with the occupation at the workplace namely occupational asthma, silicosis, black lung disease, farmers' lung disease, asbestos-linked disease, and hypersensitivity pneumonitis. Occupational lung diseases contribute toward global health and economic impacts. Prevention and control of occupational lung diseases require a collaborative effort among employers, workers, occupational physicians, pulmonary physicians, industrial hygienists, and members from other disciplines.

Imaging diagnosis of classical and new pneumoconiosis: predominant reticular HRCT pattern

Our understanding of the manifestations of pneumoconioses is evolving in recent years. Associations between novel exposures and diffuse interstitial lung disease have been newly recognized. In advanced asbestosis, two types of fibrosis are seen, probably related to dose of exposure, existence of pleural fibrosis, and the host factor status of the individual. In pneumoconiosis of predominant reticular type, nodular opacities are often seen in the early phase. The nodular pattern is centrilobular, although some in metal lung show perilymphatic distribution, mimicking sarcoidosis. High-resolution computed tomography enables a more comprehensive correlation between the pathologic findings and clinically relevant imaging findings. The clinician must understand the spectrum of characteristic imaging features related to both known dust exposures and to historically recent new dust exposures.

Chest Imaging in the Diagnosis of Occupational Lung Diseases

Imaging plays a crucial role in the diagnosis and monitoring of occupational lung diseases (OLDs); however, the sensitivity and specificity of detection and diagnosis vary greatly depending on the imaging modality used. There is substantial overlap in appearance with non-occupation-related entities. OLDs should be considered in the differential even in the absence of a provided exposure history. Because many findings are not specific, a multidisciplinary approach is important in arriving at the diagnosis and will continue to be important as workplace-related pulmonary diseases evolve with changing industrial practices and workplace regulations.

Costs of asbestosis and silicosis hospitalization in Italy (2001-2018) : Costs of asbestosis and silicosis hospitalization

BACKGROUND

Asbestosis and silicosis are preventable fibrotic forms of pneumoconiosis. Decades ago, the World Health Organization began prevention campaigns for eliminating these diseases worldwide.

PURPOSE

To establish Italian hospitalization costs of asbestosis and silicosis in relation to national adopted prevention policies.

METHODS

This is a retrospective population-based study of Italian hospitalizations treating asbestosis or silicosis in the period 2001-2018. We have extracted data from the National Hospital Discharge Registry and merged with national standard charges of hospitalizations through diagnosis-related group coding. We expressed costs in 2018 euros and evaluated data time-trends by linear normal and logistic regression models.

RESULTS

During 2001-2018, hospitalization costs per year were 3,787,540 € for asbestosis and 10,103,215 € for silicosis. There were significant annual reductions in frequency (- 41 and - 266 hospitalizations per year for asbestosis and silicosis, respectively), length of stay (- 148 and - 2781 days per year for asbestosis and silicosis, respectively) and cost (- 43,881 and - 959,516 € per year for asbestosis and silicosis, respectively) of diseases. Length and cost of hospital stay per admission significantly increased over time for asbestosis (+ 0.2 days and + 100 €, respectively, per year).

CONCLUSION

Overall hospitalizations costs were higher for silicosis than asbestosis. Over time hospitals treated fewer cases with greater severity. The decreased 2001-2018 consumption of hospital resources by patients with asbestosis or silicosis is associated with the occupational health policies instituted from the 1990s to reduce exposures to asbestos and silica. Extending existing epidemiological surveillance systems to pneumoconioses would help to control the social costs of work-related diseases.

Can BAP1 expression loss in mesothelial cells be an indicator of malignancy?

Background

Malignant mesothelioma is a highly aggressive tumor that can be confused with a benign mesothelial lesion, especially cytomorphologic lesions. BRCA1-associated protein 1 (BAP1) acts as a tumor suppressor. In this study, we aim to investigate the value of BAP1 staining of malignant mesothelioma cases with expression loss and diagnosis in cell block and biopsy tissue.

Methods

Between January 2009 and March 2017, 64 mesotheliomas, 117 reactive mesothelial hyperplasias, and 20 fibrinous pleuritis/pericarditis were diagnosed with morphologic and immunohistochemical findings in our pathology clinic and were included in the study. Formalin-fixed, paraffin-embedded tissues were immunohistochemically examined for BAP1. Inflammatory and stromal cells were used as positive internal controls. BAP1 was assessed for nuclear staining in mesothelial cells.

Results

Examinations of the relationship between patient diagnosis and BAP1 biopsy status showed that the BAP1 loss rate (76.6%) was significantly higher in malignant mesothelioma cases than in other benign diseases (0%) (p<.001). Sensitivity and specificity were 76.56% and 100%, respectively, for biopsy tissue from malignant mesothelioma. Sensitivity and specificity were both 100% for BAP1 test on cell block tissue. Furthermore, the consistency between BAP1 cell block and biopsy results was excellent (ĸ=0.90) and the correlation was significant (p<.001).

Conclusions

This study shows that BAP1 expression loss in both cytology and biopsy tissue in biopsy-confirmed malignant mesothelioma cases is an essential parameter for malignant mesothelioma diagnosis.

Asbestos exposure and autoantibody titers

Background

Asbestos is a well-known hazardous substance that causes occupational and environmental diseases including asbestosis (lung fibrosis). Silica exposure which causes silicosis (another type of lung fibrosis) has long been linked to the development of autoimmune diseases; however, there are few studies on the relationship between asbestos exposure and autoimmune diseases.

Methods

A total of 54 individuals who had worked in a former asbestos textile factory underwent autoantibody-related blood tests, chest X-ray imaging, and pulmonary function tests. Based on the job exposure matrix (JEM), the estimated asbestos exposure concentrations were determined, and the presence of asbestosis was determined by chest radiography.

Results

Scleroderma (Scl-70) and ribonucleoprotein (RNP) antibodies were significantly lowered in the pleural plaque present group than in the absent group. Additionally, Scl-70, RNP, and Sjögren's syndrome type B (SS-B) antibodies were significantly lowered in the asbestosis present group. When stratifying variables with or without asbestosis, Scl-70, Smith, SS-B, and RNP antibodies decreased in female, crocidolite handling group, and higher estimated asbestos exposure level group.

Conclusions

Contrary to our expectations that autoantibody titers would be higher in groups with high asbestos exposure or in the asbestosis group, those with asbestosis showed lower titers. But as our research has some methodological limitations, the lowered titer of autoimmune antibody in our asbestos exposed subjects could not be simply interpreted as a lowered risk of autoimmune diseases. So careful interpreting should be taken when examine autoantibodies to screening or diagnose autoimmune diseases in people with asbestos exposure. In addition, it is necessary to establish relevance of asbestosis and autoantibodies through further studies of larger scale and higher confidence levels.

Relations between vital capacity, CO diffusion capacity and computed tomographic findings of former asbestos-exposed patients: a cross-sectional study

BACKGROUND

Asbestos-related lung diseases are one of the leading diagnoses of the recognized occupational diseases in Germany, both in terms of their number and their socio-economic costs. The aim of this study was to determine whether pulmonary function testing (spirometry and CO diffusion measurement (DLCO)) and computed tomography of the thorax (TCT) are relevant for the early detection of asbestos-related pleural and pulmonary fibrosis and the assessment of the functional deficiency.

METHODS

The records of 111 formerly asbestos-exposed workers who had been examined at the Institute for Occupational and Maritime Medicine, Hamburg, Germany, with data on spirometry, DLCO and TCT were reviewed. Workers with substantial comorbidities (cardiac, malignant, silicosis) and/or pulmonary emphysema (pulmonary hyperinflation and/or TCT findings), which, like asbestosis, can lead to a diffusion disorder were excluded. The remaining data of 41 male workers (mean 69.8 years ±6.9) were evaluated. The TCT changes were coded according to the International Classification of High-resolution Computed Tomography for Occupational and Environmental Respiratory Diseases (ICOERD) by radiologists and ICOERD-scores for pleural and pulmonary changes were determined. Correlations (ρ), Cohens κ and accuracy were calculated.

RESULTS

In all 41 males the vital capacity (VC in % of the predicted value (% pred.)) showed only minor limitations (mean 96.5 ± 18.0%). The DLCO (in % pred.) was slightly reduced (mean 76.4 ± 16.6%; median 80.1%); the alveolar volume related value (DLCO/VA) was within reference value (mean 102 ± 22%). In the TCT of 27 workers pleural asbestos-related findings were diagnosed whereof 24 were classified as pulmonary fibrosis (only one case with honey-combing). Statistical analysis provided low correlations of VC (ρ = - 0.12) and moderate correlations of DLCO (- 0.25) with pleural plaque extension. The ICOERD-score for pulmonary fibrosis correlated low with VC (0.10) and moderate with DLCO (- 0.23); DLCO had the highest accuracy with 73.2% and Cohens κ with 0.45. DLCO/VA showed no correlations to the ICOERD-score. The newly developed score, which takes into account the diffuse pleural thickening, shows a moderate correlation with the DLCO (ρ = - 0.35, p < 0.05).

CONCLUSIONS

In formerly asbestos-exposed workers, lung function alterations and TCT findings correlated moderate, but significant using DLCO and ICOERD-score considering parenchymal ligaments, subpleural curvilinear lines, round atelectases and pleural effusion in addition to pleural plaque extension. DLCO also showed highest accuracy in regard to pulmonary findings. However, VC showed only weaker correlations although being well established for early detection. Besides TCT the determination of both lung function parameters (VC and DLCO) is mandatory for the early detection and assessment of functional deficiencies in workers formerly exposed to asbestos.

A case of surgically treated bilateral metachronous malignant pleural mesothelioma

In this article, we present a 59-year-old male patient who was admitted to our hospital with right pleural effusion and right-sided chest pain and diagnosed as malignant pleural mesothelioma with thoracentesis and pleural biopsy. After the patient was determined to be operable, right parietal pleurectomy + pericardial resection + diaphragmatic resection were performed and four cycles of cisplatin and pemetrexed combination as adjuvant treatment were added. The patient was followed-up without any problem for three and a half years. At this time, left-sided chest pain and leftsided effusion were noticed. Tumor was negative in thoracentesis and pleural biopsy. Then, video-assisted thoracoscopic surgery was applied, which resulted in Stage 1a malignant pleural mesothelioma. Thoracoscopic parietal pleurectomy was performed with success. Four cycles of pemetrexed single-agent therapy was performed as an adjuvant treatment. The patient died of chronic obstructive pulmonary disease and heart failure in 57^th month of the first and 21^st month of the second operation while he was tumor free. To the best of our knowledge, this case is the first operated bilateral metachronous primary malignant pleural mesothelioma in the literature.

[Asbestos and its effects on health of Icelanders - review]

Asbestos are crystallized silicate minerals that form fibers with different structures and characteristics. Asbestos fibers are very durable and can tolerate very high temperatures. Therefore it was common to use asbestos as a fire retardants, heat insulation and where high temperature is used. Asbestos has been banned in Iceland from 1983 but can still be found in large amounts in buildings, ships and hot water pipes. Large amounts of asbestos were imported in the years before the ban but diminished soon to almost nothing today. Needle or filamentous shaped dust is released when working with asbestos. It is this dust that is dangerous for health. The latent time from exposure to disease can be up to forty years. Asbestos reaches the lungs via inhalation and can cause asbestosis that is a form of lung fibrosis with slow progression. Asbestos can also cause benign pleural effusions, pleural plaques and diffuse pleural thickening. Asbestos is a carcinogen. Lung cancer is most common but asbestos is also a risk factor for cancers of other organs. Mesothelioma is most common in the pleura but can be seen in other membranes. The incidence of these tumors is high in Iceland and is still increasing among males. Of all the European countries mortality is highest in Iceland. It is important for physicians to include asbestos exposure in the differential diagnosis of lung diseases and when lung cancer is diagnosed.

Breath analysis as a diagnostic and screening tool for malignant pleural mesothelioma: a systematic review

Malignant pleural mesothelioma (MPM) is a tumour related to a historical exposure to asbestos fibres. Currently, the definite diagnosis is made only by the histological examination of a biopsy obtained through an invasive thoracoscopy. However, diagnosis is made too late for curative treatment because of non-specific symptoms mainly appearing at advanced stage disease. Hence, due to its biologic aggressiveness and the late diagnosis, survival rate is low and the patients' outcome poor. In addition, radiological imaging, like computed tomographic scans, and blood biomarkers are found not to be sensitive enough to be used as an early diagnostic tool. Detection in an early stage is assumed to improve the patients' outcome but is hampered due to non-specific and late symptomology. Hence, there is a need for a new screening and diagnostic test which could improve the patients' outcome. Despite extensive research has focused on blood biomarkers, not a single has been shown clinically useful, and therefore research recently shifted to "breathomics" techniques to recognize specific volatile organic compounds (VOCs) in the breath of the patient as potential non-invasive biomarkers for disease. In this review, we summarize the acquired knowledge about using breath analysis for diagnosing and monitoring MPM and asbestos-related disorders (ARD). Gas chromatography-mass spectrometry (GC-MS), the gold standard of breath analysis, appears to be the method with the highest accuracy (97%) to differentiate MPM patients from at risk asbestos-exposed subjects. There have already been found some interesting biomarkers that are significantly elevated in asbestosis (NO, 8-isoprostane, leukotriene B4, α-Pinene…) and MPM (cyclohexane) patients. Regrettably, the different techniques and the plethora of studies suffer some limitations. Most studies are pilot studies with the inclusion of a limited number of patients. Nevertheless, given the promising results and easy sampling methods, we can conclude that breath analysis may become a useful tool in the future to screen for MPM, but further research is warranted.

WHO/ILO work-related burden of disease and injury: Protocol for systematic reviews of occupational exposure to dusts and/or fibres and of the effect of occupational exposure to dusts and/or fibres on pneumoconiosis

BACKGROUND

The World Health Organization (WHO) and the International Labour Organization (ILO) are developing a joint methodology for estimating the national and global work-related burden of disease and injury (WHO/ILO joint methodology), with contributions from a large network of experts. In this paper, we present the protocol for two systematic reviews of parameters for estimating the number of deaths and disability-adjusted life years attributable to pneumoconiosis from occupational exposure to dusts and/or fibres, to inform the development of the WHO/ILO joint methodology.

OBJECTIVES

We aim to systematically review studies on occupational exposure to dusts and/or fibres (Systematic Review 1) and systematically review and meta-analyse estimates of the effect of occupational exposure to dusts and/or fibres on pneumoconiosis (Systematic Review 2), applying the Navigation Guide systematic review methodology as an organizing framework.

DATA SOURCES

Separately for Systematic Reviews 1 and 2, we will search electronic academic databases for potentially relevant records from published and unpublished studies, including Medline, EMBASE, Web of Science and CISDOC. We will also search electronic grey literature databases, Internet search engines and organizational websites; hand-search reference list of previous systematic reviews and included study records; and consult additional experts.

STUDY ELIGIBILITY AND CRITERIA

We will include working-age (≥15 years) study participants in the formal and informal economy in any WHO and/or ILO Member State but exclude children (<15 years) and unpaid domestic workers. Eligible risk factors will be dusts and/or fibres from: (i) asbestos; (ii) silica; and/or (iii) coal (defined as pure coal dust and/or dust from coal mining). Included outcomes will be (i) asbestosis; (ii) silicosis; (iii) coal worker pneumoconiosis; and (iv) unspecified pneumoconiosis. For Systematic Review 1, we will include quantitative prevalence studies of occupational exposure to dusts and/or fibres (i.e. no versus any exposure) stratified by country, sex, age and industrial sector or occupation. For Systematic Review 2, we will include randomized controlled trials, cohort studies, case-control studies and other non-randomized intervention studies with an estimate of any occupational exposure to dusts and/or fibres on the prevalence of, incidence of or mortality due to pneumoconiosis, compared with the theoretical minimum risk exposure level of no exposure.

STUDY APPRAISAL AND SYNTHESIS METHODS

At least two review authors will independently screen titles and abstracts against the eligibility criteria at a first stage and full texts of potentially eligible records at a second stage, followed by extraction of data from qualifying studies. At least two review authors will assess risk of bias and the quality of evidence, using the most suited tools currently available. For Systematic Review 2, if feasible, we will combine relative risks using meta-analysis. We will report results using the guidelines for accurate and transparent health estimates reporting (GATHER) for Systematic Review 1 and the preferred reporting items for systematic reviews and meta-analyses guidelines (PRISMA) for Systematic Review 2.

PROSPERO REGISTRATION NUMBER

CRD42018084131.

Asbestos exposure biomarkers in the follow-up of asbestos-exposed workers

Health surveillance of asbestos exposed workers should be stratified according to the exposure level. Unfortunately there is a lack of information regarding asbestos exposure in many working places and markers of asbestos exposure are often needed. The aim of the study was to assess the reliability of different dose and effect biomarkers in the follow up of asbestos-exposed workers. Mineralogical analysis of bronchoalveolar lavage fluid (BALF) as a biomarker of asbestos fibre burden was performed in a population of 307 male subjects occupationally exposed to asbestos. Using nonparametric statistical methods 8 variables were analyzed with respect to asbestos-related diseases and working sectors. The existence of a relationship between serum soluble mesothelin-related peptides (SMRP) and asbestos exposure levels was also investigated. Concentrations of amphiboles, chrysotile and asbestos bodies in BALF were higher in patients with asbestosis as well as in railway industry workers. A correlation between the onset of non malignant asbestos-related diseases and the levels of SMRP concentration was not found. This study confirms that fibre concentration in BALF may be considered as a reliable biomarker of previous asbestos exposure, whereas SMRP does not appear to be influenced by asbestos exposure levels.

Asbestos-related disease in upholsterers

Before its use was banned in developed countries, asbestos was widely applied in upholstery. However, the risk of asbestos diseases among upholsterers has only rarely been reported. In this case series, we present a first series of 6 workers employed in small workshops who developed several asbestos-related diseases, including pleural plaques, pleural fibrosis, and asbestosis. Exposures were intermittent and difficult to quantify, but lung asbestos content assessed by bronchoalveolar lavage was high in the 3 patients evaluated. In conclusion, upholstery work should be considered an at-risk occupation for developing asbestos-related diseases during the 20th century.

Long-term epidemiological observation of asbestos-related diseases in Poland, 1970-2015

Background

Occupational exposure to asbestos constitutes a major public health concern. Despite this in many countries, data and registration systems for occupational asbestos-related diseases are non-existent or poorly developed.

Aims

To analyse the incidence of occupational asbestos-related diseases in Poland between the years 1970 and 2015, with particular emphasis on the periods after introduction of a ban on asbestos and following introduction of a surveillance programme.

Methods

Analysis based on all medically recognized cases, certified as occupational diseases and reported obligatorily from all over the country to the Central Register of Occupational Diseases.

Results

During the period 1970-2015, 4983 cases were reported as asbestos-related diseases. The most prevalent were asbestosis, lung cancer, diseases of pleura or pericardium and mesothelioma. A considerable increase in the number of such cases from the beginning of their registration until 2004 occurred after introduction of the Amiantus programme, a nationwide programme of periodic medical examinations for former asbestos workers.

Conclusions

Introduction of a medical surveillance programme improved case recognition and allowed a more reliable estimate of the number of reported asbestos-related diseases.

Mesothelioma in Australia: a review

The incidence of malignant mesothelioma in Australia is among the highest in the world as a result of widespread use of asbestos by industry and in construction throughout the 20th century. The risk of developing malignant mesothelioma after asbestos exposure is dose-related; a transient, low dose exposure confers a correspondingly very low risk of disease. Malignant mesothelioma is a heterogeneous disease, partly explaining the limited role of biomarkers in screening and diagnosis. The prognosis remains poor, and early advice on medico-legal compensation and a collaborative team approach to managing malignant mesothelioma are both essential. Chemotherapy can have a modest treatment effect in some people. New therapies, such as immunotherapy, do not yet have a defined role in the treatment of malignant mesothelioma. As treatment options for malignant mesothelioma are limited and no cure is available, there is no established role for early detection or screening of at risk populations. A multidisciplinary approach to caring for patients with malignant mesothelioma and their carers is vital.

Serum concentrations of Krebs von den Lungen-6, surfactant protein D, and matrix metalloproteinase-2 as diagnostic biomarkers in patients with asbestosis and silicosis: a case-control study

BACKGROUND

Asbestosis and silicosis are progressive pneumoconioses characterized by interstitial fibrosis following exposure to asbestos or silica dust. We evaluated the potential diagnostic biomarkers for these diseases.

METHODS

The serum concentrations of Krebs von den Lungen-6 (KL-6), surfactant protein D (SP-D), and matrix metalloproteinase-2 (MMP-2), MMP-7, and MMP-9 were measured in 43 patients with asbestosis, 45 patients with silicosis, 40 dust-exposed workers (DEWs) without pneumoconiosis, and 45 healthy controls (HCs). Chest high-resolution computed tomography (HRCT) images were reviewed by experts blinded to the clinical data. According to the receiver operating characteristic (ROC) curve, the ideal level of each biomarker and its diagnostic sensitivity were obtained.

RESULTS

The serum KL-6 and MMP-2 concentrations were highest in patients with asbestosis, particularly in comparison with those in DEWs and HCs (P<0.05). The serum SP-D concentration was significantly higher in patients with asbestosis than in patients with silicosis, DEWs, and HCs (P<0.01), whereas no significant difference was noted among patients with silicosis, DEWs, and HCs. No significant difference in the serum MMP-7 or -9 concentration was found among patients with asbestosis, patients with silicosis, DEWs, or HCs. Among patients with asbestosis, the serum KL-6 concentration was significantly correlated with the lung fibrosis scores on HRCT and negatively correlated with the forced vital capacity (FVC) % predicted and diffusing capacity of the lung for carbon monoxide (DL_CO) % predicted. The serum SP-D and MMP-2 concentrations were negatively correlated with the DL_CO % predicted (all P<0.05). The order of diagnostic accuracy according to the ROC curve was KL-6, SP-D, and MMP-2 in patients with asbestosis alone and in the combination of both patients with asbestosis and those with silicosis. The combination of all three biomarkers may increase the possibility of diagnosing asbestosis (sensitivity, 93%; specificity, 57%) and both asbestosis and silicosis (sensitivity, 83%; specificity, 62%).

CONCLUSIONS

KL-6, SP-D, and MMP-2 are available biomarkers for the adjuvant diagnosis of asbestosis and silicosis. The combination of all three biomarkers may improve the diagnostic sensitivity for asbestosis and silicosis.

[Exploratory analysis on burden of disease attributable to asbestosis from 2006 to 2015]

Objective: To analyze the levels and trends of the burden of disease attributable to asbestosis from 2006 to 2015. Methods: Theincidence of asbestosis from 2006 to 2015 was used for calculation, with data of disability weight and remission rate from Global burden of disease study 2015 (GBD 2015) and DisMoD-MR 2.1 software for the calculation of duration and age of year onset. The reference template of GBD was adopted to calculate disability adjusted life year (DALY) , year of life lost (YLL) and year of lived with disability (YLD) value in order to analyze the level and changing trend of burden of disease attributable to asbestosis. Results: A total YLD attributable to asbestosis during 2006 and 2015 in China was 39632. The YLD burden of female was more severe than male, which accounted for 20361 in female and 19271 in male. In 2015, DALY attributable to asbestosis decreased from 8623.76 in 2006 to 6436. Among that, in 2015, YLD was 6436 and YLL was 73.76. 2006 had a highest level of DALY and 2008 had the lowest level of DALY, which accounted for 8623.76 in 2006 and 1558 in 2008. DALY during 2008 and 2015 had a fluctuant increase, and both male and female had such trend. Conclusion: The level of burden of disease attributable to asbestosis is higher in male than in female during 2006 and 2015. Between 2006 and 2015, burden of disease attributable to asbestosis has a fluctuant increase trend.

Correlation of ultra-low dose chest CT findings with physiologic measures of asbestosis

OBJECTIVES

The correlation between ultra low dose computed tomography (ULDCT)-detected parenchymal lung changes and pulmonary function abnormalities is not well described. This study aimed to determine the relationship between ULDCT-detected interstitial lung disease (ILD) and measures of pulmonary function in an asbestos-exposed population.

METHODS

Two thoracic radiologists independently categorised prone ULDCT scans from 143 participants for ILD appearances as absent (score 0), probable (1) or definite (2) without knowledge of asbestos exposure or lung function. Pulmonary function measures included spirometry and diffusing capacity to carbon monoxide (DLCO).

RESULTS

Participants were 92% male with a median age of 73.0 years. CT dose index volume was between 0.6 and 1.8 mGy. Probable or definite ILD was reported in 63 (44.1%) participants. Inter-observer agreement was good (k = 0.613, p < 0.001). There was a statistically significant correlation between the ILD score and both forced expiratory volume in 1 second (FEV₁) and forced vital capacity (FVC) (r = -0.17, p = 0.04 and r = -0.20, p = 0.02). There was a strong correlation between ILD score and DLCO (r = -0.34, p < 0.0001).

CONCLUSION

Changes consistent with ILD on ULDCT correlate well with corresponding reductions in gas transfer, similar to standard CT. In asbestos-exposed populations, ULDCT may be adequate to detect radiological changes consistent with asbestosis.

KEY POINTS

• Interobserver agreement for the ILD score using prone ULDCT is good. • Prone ULDCT appearances of ILD correlate with changes in spirometric observations. • Prone ULDCT appearances of ILD correlate strongly with changes in gas transfer. • Prone ULDCT may provide sufficient radiological evidence to inform the diagnosis of asbestosis.

Utility of Bronchoalveolar Lavage for the Diagnosis of Asbestos-Related Diseases

INTRODUCTION

Bronchoalveolar lavage (BAL) analysis has been proposed as an objective technique for confirming asbestos exposure. However, the reliability and diagnostic yield of this procedure has not been studied in Spain. The aim of this study was to assess the usefulness of the analysis of asbestos bodies (AB) in bronchoalveolar lavage (BAL) for the diagnosis of asbestos-related diseases (ARD).

METHODS

BAL samples from 72 patients (66 male, mean age 66 years) undergoing bronchoscopy were analyzed. Lung tissue from 23 of these patients was also analyzed. Asbestos exposure was assessed by anamnesis and a review of the patient's medical records. BAL and lung samples were processed and AB count was determined by light microscopy. The accepted threshold value to diagnose asbestos-related diseases was 1 AB/ml BAL or 1000 AB/gr dry tissue.

RESULTS

Thirty-nine patients reported exposure to asbestos. Of these, 13 (33%) presented AB values above 1 AB/ml BAL. In the 33 non-exposed patients, 5 (15%) presented AB values above 1 AB/ml BAL. There was a significant difference between the AB levels of exposed and non-exposed patients (P=.006). The ROC curve showed that a value of 0.5 AB/ml BAL achieved the most satisfactory sensitivity, 46%, and a specificity of 83%. The correlation between AB levels in BAL and lung was 0.633 (P=.002).

CONCLUSIONS

BAL study provides objective evidence of exposure to asbestos. The good correlation between the AB counts in BAL and lung tissue indicates that both techniques are valid for the analysis of asbestos content.

Radiologic Diagnosis of Asbestosis in Korea

Asbestosis is the most important change noted in the lung parenchyma after environmental and occupational exposure to asbestos fibers. It is characterized by diffuse interstitial pulmonary fibrosis. In Korea, the incidence of asbestosis will continue to increase for many years to come and the government enacted the Asbestos Damage Relief Law in 2011 to provide compensation to those suffering from asbestos-related diseases. Radiologic evaluation is necessary for diagnosis of asbestosis, and radiologists play a key role in this process. Therefore, it is important for radiologists to be aware of the various imaging features of asbestosis.

Carcinoma of the lung in the absence of asbestosis: The value of lung fiber burden analysis

Asbestos is universally recognized as a carcinogen for the lower respiratory tract. However, asbestos is a contributory factor in a small fraction of lung cancers, the vast majority of which are related to cigarette smoking. The challenge for the pathologist is to determine when a lung cancer may be attributed to past asbestos exposure. The finding of asbestosis either clinically or pathologically is a useful marker for such a determination. However, in the absence of asbestosis, it has been suggested that a fiber burden as determined by analytical electron microscopy within the range of asbestosis is sufficient for determination of a causal contribution. We report here an example of a case of lung cancer in which fiber burden studies showed an asbestos concentration within the range of asbestosis as determined by scanning electron microscopy (SEM).

CT Findings in People Who Were Environmentally Exposed to Asbestos in Korea

Asbestos related pleuropulmonary disease has been emerging health problem for recent years. It can cause variable clinical symptoms and radiological abnormalities. However, there has been no report for their characteristics in subjects who were environmentally exposed to asbestos. We reviewed the CT images of 35 people who were environmentally exposed to asbestos in Chungnam province, Korea. The study result showed high incidence of pleural plaque and pulmonary fibrosis on chest CT (94% and 77%, respectively). The common CT findings of lung parenchymal lesions were as follows: centrilobular opacities (94%), subpleural dot-like or branching opacities (80%), interlobular septal thickening (57%), intralobular interstitial thickening (46%), parenchymal bands (43%) and subpleural curvilinear line (29%). There were no significant differences in the prevalence of pulmonary fibrosis and pleural plaques according to sex, age and duration of exposure. In conclusion, pleural plaque and pulmonary fibrosis are common asbestos-related CT finding in the exposed people. Asbestos related lung parenchymal CT findings in the participants with environmental exposure show similar to those observed in the occupational exposure.

Asbestosis and other pulmonary fibrosis in asbestos-exposed workers: high-resolution CT features with pathological correlations

OBJECTIVE

The purpose was to identify distinguishing CT features of pathologically diagnosed asbestosis, and correlate diagnostic confidence with asbestos body burden.

METHODS

Thirty-three workers (mean age at CT: 73 years) with clinical diagnoses of asbestosis, who were autopsied (n = 30) or underwent lobectomy (n = 3), were collected. Two radiologists independently scored high-resolution CT images for various CT findings and the likelihood of asbestosis was scored. Two pathologists reviewed the pathology specimens and scored the confidence of their diagnoses. Asbestos body count was correlated with CT and pathology scores.

RESULTS

Pathologically, 15 cases were diagnosed as asbestosis and 18 cases with various lung fibroses other than asbestosis. On CT, only the score of the subpleural curvilinear lines was significantly higher in asbestosis (p = 0.03). Accuracy of CT diagnosis of asbestosis with a high confidence ranged from 0.73 to 0.79. Asbestos body count positively correlated with CT likelihood of asbestosis (r = 0.503, p = 0.003), and with the confidence level of pathological diagnosis (r = 0.637, p < 0.001).

CONCLUSIONS

Subpleural curvilinear lines were the only clue for the diagnosis of asbestosis. However, this was complicated by other lung fibrosis, especially at low asbestos body burden.

KEY POINTS

• Various patterns of pulmonary fibrosis occurred in asbestos-exposed workers. • The fibre burden in lungs paralleled confident CT diagnosis of asbestosis. • The fibre burden in lungs paralleled confident pathological diagnosis of asbestosis. • Subpleural curvilinear lines were an important CT finding favouring asbestosis.

Physical activity in people with asbestos related pleural disease and dust-related interstitial lung disease: An observational study

This study aimed to measure the levels of physical activity (PA) in people with dust-related pleural and interstitial lung diseases and to compare these levels of PA to a healthy population. There is limited data on PA in this patient population and no previous studies have compared PA in people with dust-related respiratory diseases to a healthy control group. Participants with a diagnosis of a dust-related respiratory disease including asbestosis and asbestos related pleural disease (ARPD) and a healthy age- and gender-matched population wore the SenseWear(®) Pro3 armband for 9 days. Six-minute walk distance, Medical Outcomes Study 36-item short-form health survey and the Hospital Anxiety and Depression Scale were also measured. Fifty participants were recruited and 46 completed the study; 22 with ARPD, 10 with dust-related interstitial lung disease (ILD) and 14 healthy age-matched participants. The mean (standard deviation) steps/day were 6097 (1939) steps/day for dust-related ILD, 9150 (3392) steps/day for ARPD and 10,630 (3465) steps/day for healthy participants. Compared with the healthy participants, dust-related ILD participants were significantly less active as measured by steps/day ((mean difference 4533 steps/day (95% confidence interval (CI): 1888-7178)) and energy expenditure, ((mean difference 512 calories (95% CI: 196-827)) and spent significantly less time engaging in moderate, vigorous or very vigorous activities (i.e. >3 metabolic equivalents; mean difference 1.2 hours/day (95% CI: 0.4-2.0)). There were no differences in levels of PA between healthy participants and those with ARPD. PA was reduced in people with dust-related ILD but not those with ARPD when compared with healthy age and gender-matched individuals.

Selenium and exposure to fibrogenic mineral dust: a mini-review

Individuals exposed to fibrogenic mineral dust may exhibit an impaired antioxidant system and produce high levels of reactive oxygen and nitrogen species through immune cells, contributing to the perturbation of immune cell function, inflammation, fibrosis and lung cancer. The lung diseases which are caused by inhalation of fibrogenic mineral dust, known as pneumoconioses, develop progressively and irreversibly over decades. At the moment there is no known cure. The trace element selenium has potent antioxidant and anti-inflammatory properties mediated mainly through selenoproteins. Research has demonstrated that selenium has the ability to protect against cardiovascular diseases; to kill cancer cells in vitro and reduce cancer incidence; and to immunomodulate various cellular signaling pathways. For these reasons, selenium has been proposed as a promising therapeutic agent in oxidative stress associated pathology that in theory would be beneficial for the prevention or treatment of pneumoconioses such as silicosis, asbestosis, and coal worker's pneumoconiosis. However, studies regarding selenium and occupational lung diseases are rare. The purpose of this study is to conduct a mini-review regarding the relationship between selenium and exposure to fibrogenic mineral dust with emphasis on epidemiological studies. We carried out a systematic literature search of English published studies on selenium and exposure to fibrogenic mineral dust. We found four epidemiological studies. Reviewed studies show that selenium is lower in individuals exposed to fibrogenic mineral dust. However, three out of the four reviewed studies could not confirm cause-and-effect relationships between low selenium status and exposure to fibrogenic mineral dust. This mini-review underscores the need for large follow-up and mechanistic studies for selenium to further elucidate its therapeutic effects.

Risk assessment of gastric cancer associated with asbestosis: a case report

BACKGROUND

The International Agency for Research on Cancer classifies asbestos as belonging to Carcinogen Group 2A for gastric cancer. We herein report a case of gastric cancer associated with asbestosis and describe the work-related and risk assessments of asbestos exposure for gastric cancer.

CASE PRESENTATION

The 66-year-old male patient in our case worked in asbestos spinning factories. His level of cumulated asbestos fiber exposure was estimated to be 38.0-71.0 f-yr/cc. Thus, the Excess Life Cancer Risk for lung cancer associated with asbestos exposure was 9,648×10(-5), almost 9,600 times the value recommended by the United States of America Environmental Protection Agency (1 × 10(-5)). The relative risk of developing lung cancer for this patient was more than 25 f-yr/cc, a well-known criterion for doubling the risk of lung cancer.

CONCLUSION

The patient's exposure to high-dose asbestos was sufficient to increase his risk of gastric cancer because as the risk of lung cancer increased, the risk of gastric cancer was due to increase as well. Therefore, occupational asbestos fiber exposure might be associated with gastric cancer in this case.

[Identification of occupational exposure in thoracic oncology: a Belgian experience]

INTRODUCTION

In Belgium in 2008, the body responsible for compensating and indemnifying victims of occupational diseases recognized 62 cases of lung cancer, although 702 cases were expected. There is an "underreporting" of occupational lung cancer. This study aimed to assess the number of cases of occupational lung cancer in a Belgian hospital specialized in oncology.

PATIENT AND METHOD

From September 1st, 2009 to January 31st, 2011, each new patient with lung cancer has been directed to a consultation identifying occupational exposure to lung carcinogens.

RESULTS

Among 81 occupational histories, 28 patients (35%) were found to have been definitely or probably exposed to one or more lung carcinogens (known or suspected). These patients were all male, mostly blue collar workers. Thirteen compensation claims for occupational disease have been introduced: nine recognized, one rejected and three pending.

CONCLUSION

This study demonstrates the importance of a physician trained in occupational diseases within a thoracic oncology unit in reducing the "underreporting" of occupational lung cancer and thus providing the victims with the compensation to which they are legitimately due.

Asbestosis: Past voices from the Mumbai factory floor

Background:

Asbestos′s production, processing, and consumption is on very high scale in India and it is increasing, and so do the related diseases. Asbestosis is such a disease which causes progressive respiratory disability.

Aim:

To find out perceptions and thinking about this disease and its risk among the patients which will help in constructing an effective community-based prevention and rehabilitation program.

Materials and Methods:

It was a community-based, qualitative study using a semi-structured interview schedule with 17 asbestosis patients from Mumbai, disgnosed by specialist with pulmonary function test and X-rays as per International Labour Organisation′s recommandations.

Results:

The risk percived by the patients is very less and attitude toward the illness is bengine as there is no clear understanding about the causation. The prolong latent period appears to be the main cause. It suggests a need of very strong program for prevention of asbestosis with the incorporation of worker awareness and eduaction for safety. The socio-economical status and educational levels of the workers make this floating population more vulnarable for manipulation by the corporates.

Conclusion:

Apart from the radical step of ban on asbestos, there is a need of community-based sustainable, affordable, and accessible rehabilitation program with a component of palliative care which will consider the different needs of this marginalized group. The need for such a program is intense as the number of asbestisis patients will keep on increasing till 30 to 40 years of asbestos ban.

Asbestos-Related Lung Disease

Asbestos is a high-profile health hazard. This article examines the assessment asbestos-related malignant mesothelioma and lung cancer. The risk of developing these diseases increases in proportion to the cumulative dose. As persons with heavy occupational asbestos exposures are diminishing, the observed latent period for asbestos-related disease extends making the assessment of an individual's cumulative dose is now more problematic.

Overview of asbestos issues in Korea

Asbestos is a carcinogen that causes diseases such as mesothelioma and lung cancer in humans. There was a sharp increase in the use of asbestos in Korea in the 1970s as Korea's economy developed rapidly, and asbestos was only recently banned from use. Despite the ban of its use, previously applied asbestos still causes many problems. A series of asbestos-related events that recently occurred in Korea have caused the general public to become concerned about asbestos. Therefore, it is necessary to take proper action to deal with asbestos-related events, such as mass outbreaks of mesothelioma among residents who lived near asbestos textile factories or asbestos mines. Although there have been no rapid increases in asbestos-related illnesses in Korea to date, such illnesses are expected to increase greatly due to the amount of asbestos used and long latency period. Decreasing the asbestos exposure level to levels as low as possible is the most important step in preventing asbestos-related illnesses in the next few decades. However, there is a lack of specialized facilities for the analysis of asbestos and experts to diagnose and treat asbestos-related illnesses in Korea; therefore, national-level concern and support are required.