Artificial Intelligence-based Quantification of Pleural Plaque Volume and Association With Lung Function in Asbestos-exposed Patients

PURPOSE

Pleural plaques (PPs) are morphologic manifestations of long-term asbestos exposure. The relationship between PP and lung function is not well understood, whereas the time-consuming nature of PP delineation to obtain volume impedes research. To automate the laborious task of delineation, we aimed to develop automatic artificial intelligence (AI)-driven segmentation of PP. Moreover, we aimed to explore the relationship between pleural plaque volume (PPV) and pulmonary function tests.

MATERIALS AND METHODS

Radiologists manually delineated PPs retrospectively in computed tomography (CT) images of patients with occupational exposure to asbestos (May 2014 to November 2019). We trained an AI model with a no-new-UNet architecture. The Dice Similarity Coefficient quantified the overlap between AI and radiologists. The Spearman correlation coefficient ( r ) was used for the correlation between PPV and pulmonary function test metrics. When recorded, these were vital capacity (VC), forced vital capacity (FVC), and diffusing capacity for carbon monoxide (DLCO).

RESULTS

We trained the AI system on 422 CT scans in 5 folds, each time with a different fold (n = 84 to 85) as a test set. On these independent test sets combined, the correlation between the predicted volumes and the ground truth was r = 0.90, and the median overlap was 0.71 Dice Similarity Coefficient. We found weak to moderate correlations with PPV for VC (n = 80, r = -0.40) and FVC (n = 82, r = -0.38), but no correlation for DLCO (n = 84, r = -0.09). When the cohort was split on the median PPV, we observed statistically significantly lower VC ( P = 0.001) and FVC ( P = 0.04) values for the higher PPV patients, but not for DLCO ( P = 0.19).

CONCLUSION

We successfully developed an AI algorithm to automatically segment PP in CT images to enable fast volume extraction. Moreover, we have observed that PPV is associated with loss in VC and FVC.

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.

Marked ventilation impairment due to progression of diffuse pleural thickening after cardiac surgery

A 64-year-old Japanese man presented with dyspnea and shortness of breath during exertion. Chest computed tomography revealed bilateral pleural effusion. He was drowsy because of CO₂ storage and died due to ventilatory impairment. His past medical history included a thymectomy and adjuvant radiotherapy with thymoma. He had undergone cardiac surgery and permanent pacemaker implantation. The autopsy examination revealed extensive bilateral pleural adhesions and diffuse visceral pleural thickening. An inspection of multiple lung sections failed to detect any asbestos body formation or mesothelioma. The patient's pleural effusion and diffuse pleural thickening may have exacerbated after cardiac surgery. In this case, the progression and pathophysiology of the pleural thickening could be traced by imaging and an autopsy, and we were able to estimate the factors that exacerbated the pleural thickening and ventilation impairment.

Increased production of matrix metalloproteinase-7 (MMP-7) by asbestos exposure enhances tissue migration of human regulatory T-like cells

The effects of asbestos on immunocompetent cells have been investigated. In particular, attention was paid to regulatory T cell function, which was observed using the HTLV-1 immortalized human polyclonal T cell line MT-2. Exposure to asbestos (approximately more than 25 μg/mL for 1-3 day) induced apoptosis, and we observed an increase in regulatory T cell function and acceleration of the cell cycle with continuous exposure to low concentrations of asbestos (5-10 μg/mL for more than eight months). Furthermore, cDNA microarray analysis in this study revealed that expression of matrix metalloproteinase-7 (MMP-7) was markedly higher in exposed sublines compared to original MT-2 cells. It was determined that MMP-7 had no effect on Treg function, as determined by examination of sublines and by addition of recombinant MMP-7 and neutralizing antibodies or inhibitors of MMP-7. However, when examining melting of the extracellular matrix (an MMP-7-mediated event) or the extent to which the MT-2 parent strain or long-term exposed subline cells pass through a fibronectin-coated filter, more filter passes were observed for the subline. These results suggest that the effect of asbestos fibers on Treg cells results in excessive migration of the tumor microenvironment through hypersecretion of MMP-7 together with an increase in suppressive function and enhancement of cell cycle progression. Therefore, one possible way to prevent the development of asbestos-induced cancer is to reduce the function (including MMP-7 production) or amount of Treg cells by physiologically active substances or food ingredients. Alternatively, it may be possible to invoke immune checkpoint treatments when carcinogenesis occurs.

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.

The physiological consequences of different distributions of diffuse pleural thickening on CT imaging

OBJECTIVE

Diffuse pleural thickening (DPT) refers to extensive visceral pleural fibrosis with adhesion formation to the parietal pleura obliterating the pleural space. The radiological definition of DPT remains controversial with most of the literature requiring the presence of an obliterated costophrenic angle (CPA) for defining DPT. We conducted a study to investigate the variable distributions of DPT and associated lung function deficit.

METHODS

85 patients referred to a pleural clinic with suspected pleural thickening were screened for our study. Data were collected from 37 patients with DPT confirmed on CT by size criteria (≥3 mm thick, ≥5 cm wide and ≥8 cm in length), and 21 controls with pleural plaques but no other pleuroparenchymal pathology. 27 patients were excluded. Groups were matched to age, body mass index and smoking history.

RESULTS

The percentage of predicted forced vital capacity showed a gradual decline from 98.9% for the control group to 83.5% in the DPT without CPA obliteration group (p < 0.05), to 79.5% in the unilateral DPT group (p < 0.001) and 66.7% in the bilateral group (p < 0.001). Similar reductions were seen in the percentage of predicted total lung capacity in the DPT with no CPA obliteration group and the bilateral DPT group.

CONCLUSION

Our study shows an incremental reduction in the forced vital capacity and total lung capacity in DPT without CPA obliteration, unilateral and bilateral DPT when compared with a matched control group. Advances in knowledge: Different distributions of DPT including no CPA obliteration can cause respiratory impairment, with bilateral DPT being the worst affected.

Serum protein identification and quantification of the corona of 5, 15 and 80 nm gold nanoparticles

When nanoparticles (NP) enter the body they come into contact with body fluids containing proteins which can adsorb to their surface. These proteins may influence the NP interactions with the biological vicinity, eventually determining their biological fate inside the body. Adsorption of the most abundantly binding proteins was studied after an in vitro 24 hr incubation of monodisperse, negatively charged 5, 15 and 80 nm gold spheres (AuNP) in mouse serum by a two-step analysis: proteomic protein identification and quantitative protein biochemistry. The adsorbed proteins were separated from non-adsorbed proteins by centrifugation and gel electrophoresis and identified using a MALDI-TOF-MS-Proteomics-Analyzer. Quantitative analysis of proteins in gel bands by protein densitometry, required the focus on predominantly binding serum proteins. Numerous proteins adsorbed to the AuNP depending on their size, e.g., apolipoproteins or complement C3. The qualitative and quantitative amount of adsorbed proteins differed between 5, 15 and 80 nm AuNP. Band intensities of adsorbed proteins decreased with increasing AuNP sizes based not only on their mass but also on their surface area. Summarizing, the AuNP surface is covered with serum proteins containing transport and immune related proteins among others. Hence, protein binding depends on the size, surface area and curvature of the AuNP.

Concentrations of asbestos fibers and metals in drinking water caused by natural crocidolite asbestos in the soil from a rural area

Asbestos fibers and metals in drinking water are of significant importance to the field of asbestos toxicology. However, little is known about asbestos fibers and metals in drinking water caused by naturally occurring asbestos. Therefore, concentrations of asbestos fibers and metals in well and surface waters from asbestos and control areas were measured by scanning electron microscopy (SEM), inductively coupled plasma (ICP) optical emission spectrometer, and ICP-mass spectrometry in this study. The results indicated that the mean concentration of asbestos fibers was 42.34 millions of fibers per liter by SEM, which was much higher than the permission exposure level. The main compositions of both asbestos fibers in crocidolite mineral and in drinking water were Na, Mg, Fe, and Si based on energy dispersive X-ray analysis. This revealed that the drinking water has been contaminated by asbestos fibers from crocidolite mineral in soil and rock. Except for Cr, Pb, Zn, and Mn, the mean concentrations of Ni, Na, Mg, K, Fe, Ca, and SiO2 were much higher in both surface water and well waters from the asbestos area than in well water from the control area. The results of principal component and cluster analyses indicated that the metals in surface and well waters from the asbestos area were significantly influenced by crocidolite mineral in soil and rock. In the asbestos area, the mean concentrations of asbestos fibers and Ni, Na, Mg, K, Fe, Ca, and SiO2 were higher in surface and well waters, indicating that asbestos fibers and the metals were significantly influenced by crocidolite in soil and rock.

Impacts of land use on spatial distribution of mortality rates of cancers caused by naturally occurring asbestos

This study investigated the spatial distributions of mortality rates of six cancers: mesothelioma, lung cancer, intestinal cancer, nasopharyngeal and laryngeal cancer, liver cancer, and stomach cancer in Dayao using Geographic Information Systems. Relationships between the mortality rates of the six cancers and land use patterns were investigated by Pearson Correlation Coefficients. The results indicated that the mortality rates of nasopharyngeal and laryngeal cancer, lung cancer, intestinal cancer, and mesothelioma were significantly associated with outcropped asbestos. Both the proportions of farmland and urban area were positively related to the mortality rates of nasopharyngeal and laryngeal cancer, lung cancer, intestinal cancer, and mesothelioma, and significant negative correlations were found between the proportion of forestland and nasopharyngeal and laryngeal cancer and intestinal cancer. It can be concluded that naturally occurring asbestos may significantly elevate the mortality rates of nasopharyngeal and laryngeal cancer, intestinal cancer, lung cancer, and mesothelioma. Moreover, higher proportions of farmland, urban area, and lower proportions of forested land may elevate the mortality rate of the four cancers.

Therapeutic antitumor efficacy of anti-epidermal growth factor receptor antibody, cetuximab, against malignant pleural mesothelioma

Epidermal growth factor receptor (EGFR) is commonly overexpressed in malignant pleural mesothelioma (MPM). Cetuximab is a chimeric mouse-human antibody targeted against EGFR and induces potent antibody-dependent cellular cytotoxicity (ADCC). The action of cetuximab against MPM cells has not been well studied. Therefore, in this study, we investigated the antitumor activity of cetuximab against MPM cell lines, particularly with respect to ADCC activity in vitro and in vivo. EGFR expression of MPM cells was measured by a quantitative flow cytometric analysis and immunohistochemistry. The effect of cetuximab on growth inhibition was assessed using a modified MTT assay. The ADCC activity was measured by a 4-h ⁵¹Cr release assay using fresh or IL-2-activated peripheral blood mononuclear cells. In vivo antitumor activity of cetuximab was evaluated using an orthotopic implantation mouse model. Cetuximab-mediated ADCC activity against MPM cells was observed at low concentration (0.25 mg/ml) and was enhanced by IL-2, whereas no direct effect on growth inhibition was detected. A logarithmic correlation was observed between the number of EGFRs on MPM cells and ADCC activity. Low EGFR expression on the MPM cells, which was weakly detectable by immunohistochemistry, was sufficient for maximum ADCC activity. In the mouse model, cetuximab treatment with or without IL-2 significantly inhibited intrathoracic tumor growth and prolonged their survival. Our study shows that cetuximab has potent anti-MPM activity both in vitro and in vivo, mainly through the immunologic mechanism of ADCC. Cetuximab has the potential to be used as a novel therapy for MPM patients.

Incidence of the pneumoconioses in the United Kingdom general population between 1997 and 2008

BACKGROUND

The incidence of the pneumoconioses in the UK is primarily estimated using occupational-based registries and disability pension schemes. These sources indicate a downward trend in the incidence of the pneumoconioses from 1995 onwards. There are no previously published general population-based observational studies quantifying the incidence of the pneumoconioses in the UK.

OBJECTIVES

The aim of this study was to investigate the incidence of the pneumoconioses in the UK general population between 1997 and 2008 using data from the General Practice Research Database (GPRD).

METHODS

Data from the UK-based GPRD were used to estimate the incidence of pneumoconioses over a 12-year period (1997-2008). Crude incidence rates for asbestosis and non-asbestos-related pneumoconioses were stratified by gender, age group and calendar period, and rate ratios were adjusted using Poisson regression.

RESULTS

The majority of cases was diagnosed with asbestosis, and the overall, crude incidence density for this pneumoconiosis during the 12-year study period was 2.7 (95% confidence interval 2.5-2.9) per 100,000 person-years. The incidence increased progressively during the period 1997-2005 and then decreased slightly during the period 2006-2008, even after controlling for the strong effect of an ageing UK population. The non-asbestos-related pneumoconioses, in contrast to asbestosis, showed a progressive reduction in incidence from 2003 onwards.

CONCLUSIONS

This study demonstrates that the pneumoconioses remain an important public health issue and, furthermore, documents an overall increase in asbestosis incidence in the UK between 1997 and 2008.

Intratumoral Wnt2B expression affects tumor proliferation and survival in malignant pleural mesothelioma patients

Malignant pleural mesothelioma (MPM) is an aggressive thoracic tumor with a poor prognosis. We performed a comprehensive clinical study on the intratumoral expression of Wnt1, Wnt2B and Wnt5A in MPM. One hundred and seven MPM patients were investigated. Immunohistochemistry was performed to evaluate the intratumoral expression of Wnt1, Wnt2B, Wnt5A, survivin and c-Myc, and the Ki-67 proliferation index. The apoptotic index was evaluated by the TUNEL method. Among the 107 MPMs, 23 MPMs (21.5%) were Wnt1-high tumors, 72 MPMs (67.3%) were Wnt2B-high tumors and 54 MPMs (50.5%) were Wnt5A-high tumors. There was no correlation among the levels of Wnt expression. The percentage of Wnt2B-positive tumors was significantly higher compared to that of the other Wnts (p<0.0001). Furthermore, intratumoral Wnt2B expression significantly correlated with the expression of survivin (p<0.001) and c-Myc (p<0.001). Regarding tumor biology, the Ki-67 proliferation index was significantly higher in the Wnt2B-high tumors than in the Wnt2B-low tumors (p=0.0438). In addition, the overall survival was significantly lower in patients with Wnt2B-high tumors than in those with Wnt2B-low tumors (p=0.0238). A Cox multivariate analysis also demonstrated the Wnt2B status to be a significant prognostic factor in MPM patients (p=0.0042). Intratumoral Wnt2B expression was associated with the expression of survivin and c-Myc, tumor proliferation and patient survival in MPM. Wnt2B is a potential molecular target for the treatment of Wnt2B-overexpressing MPMs.

An electronic nose distinguishes exhaled breath of patients with Malignant Pleural Mesothelioma from controls

BACKGROUND

Malignant Pleural Mesothelioma (MPM) is a tumour of the surface cells of the pleura that is highly aggressive and mainly caused by asbestos exposure. Electronic noses capture the spectrum of exhaled volatile organic compounds (VOCs) providing a composite biomarker profile (breathprint).

OBJECTIVE

We tested the hypothesis that an electronic nose can discriminate exhaled air of patients with MPM from subjects with a similar long-term professional exposure to asbestos without MPM and from healthy controls.

METHODS

13 patients with a histology confirmed diagnosis of MPM (age 60.9±12.2 year), 13 subjects with certified, long-term professional asbestos exposure (age 67.2±9.8), and 13 healthy subjects without asbestos exposure (age 52.2±16.2) participated in a cross-sectional study. Exhaled breath was collected by a previously described method and sampled by an electronic nose (Cyranose 320). Breathprints were analyzed by canonical discriminant analysis on principal component reduction. Cross-validated accuracy (CVA) was calculated.

RESULTS

Breathprints from patients with MPM were separated from subjects with asbestos exposure (CVA: 80.8%, sensitivity 92.3%, specificity 85.7%). MPM was also distinguished from healthy controls (CVA: 84.6%). Repeated measurements confirmed these results.

CONCLUSIONS

Molecular pattern recognition of exhaled breath can correctly distinguish patients with MPM from subjects with similar occupational asbestos exposure without MPM and from healthy controls. This suggests that breathprints obtained by electronic nose have diagnostic potential for MPM.

Reductive alteration of the regulatory function of the CD4(+)CD25(+) T cell fraction in silicosis patients

Causal links have been documented between silica and rheumatoid arthritis, lupus erythematosus, systemic sclerosis and glomerulonephritis. Two different effects of silica have been suggested, an enhanced inflammatory response in the pulmonary region (e.g. activation of alveolar macrophages) and dysregulation of autoimmunity. Based on our previous reports showing in vitro activation of peripheral T cells by silica and reduced regulatory function of the peripheral CD4(+)CD25(+) fraction in which FoxP(3)+ regulatory T cells (Treg) are located, reconstitution of the CD4(+)CD25(+) fraction in silicosis patients (SILs) was investigated. Since T cells in peripheral CD4(+)CD25(+) and CD4(+)CD25(-) (effector T cells; Teff) fractions from SILs showed higher expression of pd-1 (a marker gene for T cell activation) in comparison to that of healthy donors (HDs), chronic T cell activation was considered to have occurred in SILs. In this study, a higher expression of the CD95/Fas molecule in Treg was recorded from silicosis patients (SILs) compared to healthy donors (HDs), and excess loss of FoxP3(+) Treg in freshly isolated peripheral blood mononuclear cells (PBMCs) from SILs relative to HDs was demonstrated when these cells were cultured with silica ex vivo, whereas CD25(+) cells were not reduced due to contamination of activated Teff in the CD4(+)CD25(+) fraction. The activation of both Teff and Treg results in reconstitution of the peripheral CD4(+)CD25(+) fraction, loss of Treg and contamination of activated Teff, resulting in reduction of the number and function of Treg. These results contribute to our understanding of the development of autoimmune diseases found in SILs.

Interaction of gold nanoparticles with common human blood proteins

In order to better understand the physical basis of the biological activity of nanoparticles (NPs) in nanomedicine applications and under conditions of environmental exposure, we performed an array of photophysical measurements to quantify the interaction of model gold NPs having a wide range of NP diameters with common blood proteins. In particular, absorbance, fluorescence quenching, circular dichroism, dynamic light scattering, and electron microscopy measurements were performed on surface-functionalized water-soluble gold NPs having a diameter range from 5 to 100 nm in the presence of common human blood proteins: albumin, fibrinogen, gamma-globulin, histone, and insulin. We find that the gold NPs strongly associate with these essential blood proteins where the binding constant, K, as well as the degree of cooperativity of particle--protein binding (Hill constant, n), depends on particle size and the native protein structure. We also find tentative evidence that the model proteins undergo conformational change upon association with the NPs and that the thickness of the adsorbed protein layer (bare NP diameter <50 nm) progressively increases with NP size, effects that have potential general importance for understanding NP aggregation in biological media and the interaction of NP with biological materials broadly.

Environmental asbestos-related pleural plaque in southeast of Turkey

It is known that many malignant and benign pleural diseases occur due to environmental exposure to mineral fibers. Calcified pleural plaque (CPP) is an important sign of asbestos exposure on chest radiographic examination. To study the possible change in the prevalence of CPP and diffuse pleural thickening 3 decades after cessation of asbestos exposure. CPP were detected in 29.9% of the villagers; 4.7% had diffuse pleural thickening and 0.7% had asbestosis. The significant variable for CPP and diffuse pleural thickening was age. The youngest villager with CPP was 33 years of age and the prevalence of CPP increased with an increase in age. The reason for our cases with CPP being of advanced age is the discontinuation of asbestos exposure. This finding enables us to suggest that environmental asbestos-related disease will gradually decrease in future decades.

Up-regulation of Bcl-xl by hepatocyte growth factor in human mesothelioma cells involves ETS transcription factors

Bcl-xl and the hepatocyte growth factor (HGF) receptor c-Met are both highly expressed in mesotheliomas, where they protect cells from apoptosis and can confer resistance to conventional therapeutic agents. In our current study, we investigate a model for the transcriptional control of Bcl-xl that involves ETS transcription factors and the HGF/Met axis. In addition, the effects of activated c-Met on the phosphorylation of the ETS family transcriptional factors were examined. The transient expression of ETS-2 and PU.1 cDNAs in mesothelioma cell lines resulted in an increase in the promoter activity of Bcl-xl and consequently in its mRNA and protein expression levels, whereas the transcriptional repressor Tel suppressed Bcl-xl transcription. The activation of the HGF/Met axis led to rapid phosphorylation of ETS family transcription factors in mesothelioma cells through the mitogen-activated protein kinase pathway and via nuclear accumulation of ETS-2 and PU.1. A chromatin immunoprecipitation assay further demonstrated that the activation of c-Met enhanced the binding of ETS transcriptional factors to the Bcl-x promoter. Finally, we determined the Bcl-xl and phosphorylated c-Met expression levels in mesothelioma patient samples; these data suggest a strong correlation between Bcl-xl and phosphorylated c-Met levels. Taken together, these findings support a role for c-Met as an inhibitor of apoptosis and an activator of Bcl-xl.

Hospitalization in Winnipeg, Canada due to occupational disease: a pilot study

BACKGROUND

The objectives of this study were to identify the extent of occupational exposures to hazardous substances amongst male medical inpatients and to determine the extent to which these exposures may have contributed to the development of medical conditions.

METHODS

A random sample of 297 male who were admitted from outside the hospital to the medical wards to a large tertiary care hospital, were between age 18-75 and could communicate in English completed an occupational history questionnaire. This information was merged with an inpatient database which contained patient demographics, admission diagnoses, and co-morbidity data. A specialist in occupational medicine and internal medicine determined whether the medical conditions the participants had were related to their exposures.

RESULTS

One individual had a condition causing admission that was related to his work and 12 others (4%) had a condition that was possibly related to their work which had caused symptoms. One additional individual was found to have asymptomatic asbestos related pleural fibrosis. Fourteen of 37 possible harmful occupational exposures were reported by more than 10% of the study participants. On average each participant reported 5.5 exposures.

CONCLUSIONS

Occupational exposures to male medical inpatients are common. For 4.4% (13/297) of male admissions to the general medical wards from the emergency room occupational factors may have played a role in the development of medical conditions which led to admission or to major co-morbidities. Detailed occupational histories will likely lead to more suspected cases of work related medical admissions.

Biomarkers for malignant pleural mesothelioma: current status

Malignant pleural mesothelioma (MPM) is an aggressive tumor with poor prognosis, whose main etiology is exposure to asbestos fibers. The incidence of MPM is anticipated to increase worldwide during the first half of this century. For various reasons, MPM is difficult to diagnose and is notoriously refractory to most treatments. However, recently two active chemotherapy regimens have been demonstrated to significantly increase survival in patients with MPM, and several therapeutic agents and strategies are currently under evaluation.Researchers have actively sought MPM biomarkers for more than 20 years. Biomarkers would be helpful in managing three clinical aspects of MPM: early diagnosis, prognosis, and treatment outcome prediction. The aims of the present review are to summarize the published and recently presented data on MPM biomarkers and to identify the prospects for future translational research projects.Among the 'classical' diagnostic biomarkers measured in biological fluids, such as cytokeratins and cell surface antigens, none discriminate patients with MPM from those with other malignancies and nonmalignant diseases. Osteopontin, soluble mesothelin, and megakaryocyte potentiating factor (MPF) appear to be the most promising of the recent biomarkers, but are still subject to some limitations. Osteopontin lacks specificity for mesothelioma, while both soluble mesothelin and MPF lack sensitivity for detecting non-epithelial subtypes. Panels consisting of a small set of biomarkers do not improve the diagnostic yield, and results from molecular profiling are too preliminary to be brought into daily clinical practice. While a large number of biomarkers have been assessed in biological fluids and tumor tissue for their prognostic value, none have had a widespread impact on clinical practice. In contrast, data concerning predictive biomarkers are very limited, even though they are most interesting from the perspective of clinicians.Additional prospective studies, in large and independent samples of patients, with rigorous statistical methodology and standardized laboratory techniques are now warranted to validate and define the precise value of diagnostic and prognostic MPM biomarkers. Future research efforts should focus on biomarkers predictive of the efficacy and toxicity of standard chemotherapy. Translational research should be systematically incorporated into the design of clinical trials assessing new targeted agents in MPM.

Adrenal failure caused by a retroperitoneal malignant mesothelioma

A 62-year-old man presented with clinical signs of acute abdominal pain and adrenal insufficiency. Computerized tomographic scans revealed bilateral adrenal tumors and the left adrenal tumor was surgically resected. The patient was found to have retroperitoneal mesothelioma presenting as bilateral metastatic adrenal tumors, which were well controlled by systemic chemotherapy with CDDP and 5-FU. This case appears to be the first reported case in the literature of adrenal failure due to bilateral adrenal infiltration caused by retroperitoneal malignant mesothelioma.