[Systemic sclerosis and occupational exposures: About a case in a driller-powderman]. / Sclérodermie systémique et expositions professionnelles: à propos d'un cas chez un foreur-artificier.

INTRODUCTION: Erasmus' syndrome is the association between systemic sclerosis and silica exposure. CASE REPORT: We report a case of this syndrome in a driller-powderman exposed to silica and nitro compounds contained in explosives. CONCLUSION: Physiopathology and etiologies of systemic sclerosis are still not well known. However, nitric oxide, a product of nitro compounds metabolism, is involved in the physiopathology of the disease: it seems thus licit to wonder about the consequences of an uncontrolled occupational exposure to nitric oxide on the vascular function, already damaged by systemic sclerosis. To a wider extent, our report highlights the importance of a comprehensive and detailed collection of occupational exposures for patients diagnosed with systemic sclerosis.

[Compensation for occupational diseases after tomodensitometry screening for benign pleuro-pulmonary disease in a multiregional post-occupational medical surveillance program of asbestos-exposed retired workers]. / Déclaration et reconnaissance en maladie professionnelle après dépistage tomodensitométrique de maladies pleuropulmonaires bénignes dans le programme multirégional de surveillance postprofessionnelle de personnes exposées à l'amiante.

BACKGROUND: Underreporting of occupational diseases related to asbestos exposure remains a matter of concern in France. The aim of this study was to evaluate the number of claims for compensation for asbestos-related non-malignant pulmonary or pleural occupational disease in subjects having undergone a chest CT-scan in a multiregional screening programme. METHODS: Among the 5444 voluntary retired asbestos-exposed subjects recruited in four regions between 2003 and 2005 who had undergone a chest CT-scan, the number of claims for compensation for an asbestos-related pulmonary or pleural benign disease was analysed in 2006 and 2010. RESULTS: Following CT-scan screening, 17.2% of participants were acknowledged as presenting with an asbestos-related non-malignant occupational disease, essentially pleural plaques, by the French National Health Insurance fund. Underreporting decreased as duration of follow-up after CT-scan increased. Nevertheless, 4 years after CT-scan, underreporting was still as high as 36% for subjects identified as presenting with pleural plaques. Mean duration between the date of CT-scan and the date of recognition as occupational disease was 7.4 months, shorter in cases where screening was coordinated by specialized centres. CONCLUSION: A plan of action for an easier claiming process for compensation of asbestos-related diseases is desired. This could probably be obtained through improved sensitization of physicians engaged in the follow-up of asbestos-exposed subjects, and by standardization of the interpretation and reporting of asbestos-related abnormalities observed on chest CT-scans.

[What tools should be used for follow-up post occupational exposure? What should be the frequency?]. / Quels outils doivent être utilisés pour le suivi post-professionnel ? Quel est le rythme de ce suivi ?

As long as the value of screening for cancers related to asbestos is not proven in the population at risk, the medical benefits of follow-up post-professional exposure remain uncertain and the only justification is to answer the questions of anxious retired workers concerning the consequences of their past-exposure and to provide compensation for any abnormalities that are demonstrated. In this country, to answer the questions posed in the title of this contribution in the case of pathologies related to asbestos, it is necessary, after verifying the fact and the level of exposure, to identify the pleural or pulmonary fibrosis and, above all, the pleural plaques, which constitute the essential lesions currently screened for. Thoracic CT scanning without contrast is the examination of choice to achieve this objective. There are, however, two significant problems. On one hand there is a high incidence of pulmonary micronodules, the necessary surveillance of which requires subsequent scans, leading to increased irradiation and anxiety. On the other hand the diagnostic uncertainty concerning discrete lesions is a source of confusion for the persons followed-up. There are, at present, neither scientific criteria to determine the optimum frequency of examination nor any arguments for replacing the pragmatic proposals of the consensus conference of 1999. It is important, therefore, to provide a medical assessment appropriate to the symptoms and anxiety expressed by a person previously exposed to asbestos. Overall it is necessary to question the benefit to the exposed person, in terms of quality of life, of a regular search for lesions that would usually be asymptomatic if not identified. Would it not be more judicious and more equitable to compensate persons whose past-exposure is sufficient to increase significantly their risk of cancer independently of the presence of benign abnormalities.

Pulmonary nodules detected by thoracic computed tomography scan after exposure to asbestos: diagnostic significance.

OBJECTIVE: To analyse the relationship between pulmonary nodules detected by radiologists using computed tomography and cumulative exposure to asbestos or asbestos-related pleuro-pulmonary diseases in 5662 asbestos-exposed subjects, and the relationship between pulmonary nodules and thoracic cancer, to determine whether a specific surveillance strategy based on cumulative asbestos exposure should be adopted. DESIGN: Standardised incidence and mortality ratios (SIR) for lung cancer and pleural mesothelioma were calculated in patients with and without mention of pulmonary nodules and compared using comparative morbidity figures. RESULTS: A significant excess incidence of primary lung cancer and pleural mesothelioma was observed among subjects presenting with pulmonary nodule(s) (SIR respectively 1.95, 95%CI 1.22-2.95, and 11.88, 95%CI 3.20-30.41). However, there was no significant relationship between pulmonary nodules mentioned by radiologists and cumulative asbestos exposure or between pulmonary nodules and the presence of asbestos-related benign diseases. CONCLUSIONS: This study confirms the expected excess prevalence of lung cancer in subjects presenting with pulmonary nodules according to the radiologist's report, and shows the absence of relationship between the presence of nodules and level of cumulative asbestos exposure. Our study therefore offers no argument in favour of specific surveillance modalities based on estimated cumulative asbestos exposure.

Asbestos-related cancer risk in patients with asbestosis or pleural plaques.

INTRODUCTION: The relationships between benign asbestos-related diseases (asbestosis and pleural plaques) and thoracic cancers are still debated. The aim of this paper was to review the epidemiological data relevant to this issue. CURRENT KNOWLEDGE: Published studies show a significant relationship between occupational exposure to asbestos and lung cancer risk, even in the absence of abnormalities consistent with asbestosis on the postero-anterior chest x-ray. For a given cumulative asbestos exposure, the presence of radiographic evidence of asbestosis is associated with an increased risk of lung cancer. Among asbestos-exposed individuals, those having radiographic evidence of pleural plaques are at increased risk for lung cancer and pleural mesothelioma, compared to the general population. However, there is no evidence that pleural plaque confers an increased risk of lung cancer or pleural mesothelioma within a population of individuals having the same cumulative asbestos exposure. PERSPECTIVES: The studies identified for this review relied only on chest radiograph data. Studies involving accurate evaluations of asbestos exposure and computed tomography of the chest are needed. CONCLUSION: Currently available data indicate that patient follow-up modalities should be dictated solely by the estimated cumulative asbestos exposure and not by the existence of pleural plaques.

Occupational asbestos exposure and digestive cancers - a cohort study.

BACKGROUND: Although the role of asbestos in the genesis of mesothelioma and primary bronchopulmonary cancers has been established, results from studies focusing on the relationship between occupational exposure to asbestos and digestive cancer remain contradictory. AIM: To determine whether occupational asbestos exposure increases the incidence of digestive cancers. METHODS: Our study was a retrospective morbidity study based on 2024 subjects occupationally exposed to asbestos. The incidence of digestive cancer was calculated from 1st January 1978 to 31st December 2004 and compared with levels among the local general population using Standardized Incidence Ratios. Asbestos exposure was assessed using the company's job exposure matrix. RESULTS: Eighty-five cases of digestive cancer were observed within our cohort, for an expected number of 66.90 (SIR = 1.27 [1.01; 1.57]). A significantly elevated incidence, particularly notable among women, was observed for peritoneal mesothelioma, independently of exposure levels. A significantly elevated incidence was also noted among men for cancer of small intestine and oesophagus, for cumulative exposure indexes for asbestos above 80 fibres/mL x years. A significantly elevated incidence of cancer of the small intestine was also observed among men having been exposed to asbestos for periods in excess of 25 years and for mean exposure levels in excess of 4 fibres/mL. CONCLUSIONS: This study suggests the existence of a relationship between exposure to asbestos and cancer of the small intestine and of the oesophagus in men.

[Asbestos-related cancer risk in the presence of asbestosis or pleural plaques]. / Risque de cancer lié à l'amiante en présence d'asbestose ou de plaques pleurales.

INTRODUCTION: The relationships between benign asbestos-related diseases (asbestosis and pleural plaques) and thoracic cancers are still debated. The aim of this paper is to analyse epidemiological data which investigate this topic. STATE OF THE ART: Published studies show that there is a significant relationship between occupational exposure to asbestos and lung cancer risk, even in the absence of abnormalities consistent with asbestos exposure on postero-anterior chest x-ray. In subjects with occupational exposure to asbestos, an increased risk of lung cancer and pleural mesothelioma is observed in subjects with pleural plaques on chest x-ray, in comparison with the general population. In exposed subjects with similar cumulative exposure to asbestos, it is not demonstrated that pleural plaques are associated with an increased risk of lung cancer or pleural mesothelioma. PERSPECTIVES: All the analysed studies are only based on radiographic data. Their results must be confirmed by additional studies including a rigorous evaluation of the cumulative exposure to asbestos and chest CT-scans. CONCLUSION: In the present state of knowledge, isolated pleural plaques do not justify specific medical surveillance, as compared to that required by the mere estimated cumulative exposure to asbestos.

Performance of chest radiograph and CT scan for lung cancer screening in asbestos-exposed workers.

OBJECTIVES: The aim was to compare, in a cohort of asbestos-exposed workers, the sensitivity and the specificity of low-radiation helical chest CT scan with chest radiograph for the biennial screening of bronchopulmonary cancer, according to the size of detected nodules. MATERIAL AND METHODS: The screening procedure consisted of biennial chest radiograph and monodetector chest CT scan, given to 972 individuals who had been highly exposed to asbestos. A total of 2555 screening procedures were performed. The study focuses on the 1230 screening procedures for which a 2-year follow-up period was available. RESULTS: Twenty-four cases of bronchopulmonary cancer were diagnosed. CT scan detected 20 cancers, 12 of which had not been detected by chest radiograph. Sensitivity of chest radiograph and CT scan were, respectively, 33% and 83%, lesions measuring over 2 mm in diameter being considered as suspect. The specificity of chest radiograph and CT scan were, respectively, 95% and 78%. Calculation of the differential false positive/true positive (FP/TP) ratio and the receiver operating characteristic curve, performed for both chest radiograph and CT scan, facilitated the determination of the best possible compromise between specificity and sensitivity, according to the diameter threshold applied for considering a nodule as suspect. CONCLUSIONS: Although this study confirms the superior sensitivity of chest CT scan compared with conventional chest radiograph, the associated loss in specificity leads to a recommended diameter of 5 mm as the threshold for considering non-calcified lesions as "suspect", for the surveillance of asbestos-exposed individuals.

Pleural plaques and asbestosis: dose- and time-response relationships based on HRCT data.

Most studies on asbestos-related diseases are based on chest radiographs, and dose-response relationships are still controversial. The aim of this study was to describe the most relevant parameters of asbestos exposure linked to pleural plaques and asbestosis diagnosed by high-resolution computed tomography (HRCT). A large screening programme including systematic HRCT examinations was organised from 2003 to 2005 in France for formerly asbestos-exposed workers. The time since first exposure (TSFE), level, duration and cumulative exposure to asbestos were used in adjusted unconditional logistic regression to model the relationships of the two diseases. Analysis of a population of 5,545 subjects demonstrated that TSFE (p<0.0001) and cumulative exposure (p = 0.02) (or level, depending on the models used), were independently associated with the frequency of pleural plaques. Only cumulative exposure (p<0.0001) or level of exposure (p = 0.02) were significantly associated with asbestosis. All trend tests were significant for these parameters. To date and to our knowledge, this study is the largest programme based on HRCT for the screening of asbestos-exposed subjects. Both time-response and dose-response relationships were demonstrated for pleural plaques, while only dose-response relationships were demonstrated for asbestosis. These parameters must be included in the definition of high-risk populations for HRCT-based screening programmes.

Computed tomography findings in urban transportation workers with low cumulative asbestos exposure.

OBJECTIVE: To assess the frequency of computed tomography (CT) scan pleural and interstitial changes in a population of urban transportation workers with low cumulative exposure to asbestos, and to measure inter-reader agreement. DESIGN: A total of 269 male volunteers (mean age 54.0 +/- 2.3 years, mean estimated cumulative exposure index 1.7 +/- 2.3 fibres/ml-years), underwent a CT scan which was read independently by three experienced readers, with further consensus reading in case of pleural or parenchymal abnormalities. Inter-reader agreement was assessed by means of Kappa statistic. RESULTS: On consensus reading, four subjects had interstitial opacities, three had diffuse pleural thickening and 26 (9.7%) had pleural plaques that were unilateral in 65% of cases and < or =2 mm thick in 54% of cases. No correlation was observed between pleural plaques and latency, duration of exposure or cumulative exposure. The inter-reader agreement for the detection of pleural abnormalities was fair. CONCLUSION: In this relatively young population with low cumulative exposure to asbestos, the prevalence of pleural abnormalities was low. These abnormalities were very limited in thickness and extent, leading to marked inter-reader variability and making it difficult to assess their relationship to asbestos exposure.

[Computed tomographic atlas of benign asbestos related pathology]. / Atlas iconographique tomodensitométrique des pathologies bénignes de l'amiante.

The demonstration by computed tomography of abnormalities related to asbestos is essential for the recognition of industrial disease, the compensation of which has considerable economic consequences. The use of computed tomography, the most reliable technique for the detection of pleuro-parenchymatous abnormalities related to asbestos exposure, has increased considerably in France since the publication of the results of a consensus conference in Paris in 1999. Since that time, developments in CT technology have noticeably modified the protocols of investigation and increased the sensitivity of the detection of pleural and interstitial parenchymatous abnormalities and of nodules. The technical recommendations and those for the interpretation of pleural and parenchymatous abnormalities need to be well known. They are presented in the form of an atlas that gives detailed criteria for asbestosis, pleural plaques and pleural fibrosis. The diagnosis of pleural plaques depends on the combination of clear limits at the pleural and pulmonary interface, typical topography and multiple, bilateral localization. In the context of asbestos exposure the plaques are characteristic of this exposure, unlike diffuse pleural thickening, crow's feet images, parenchymatous bands and entrapped atalectasis. The writing of the radiological report would be most appropriate on this basis.

[Computed tomographic atlas of benign asbestos related pathology]. / Atlas iconographique tomodensitométrique des pathologies bénignes de l'amiante.

The demonstration by computed tomography of abnormalities related to asbestos is essential for the recognition of industrial disease, the compensation of which has considerable economic consequences. The use of compute tomography, the most reliable technique for the detection of pleuro-parenchymatous abnormalities related to asbestos exposure, has increased considerably in France since the publication of the results of a consensus conference in Paris in 1999. Since that time, developments in technology have noticeably modified the protocols of investigation and increased the sensitivity of the detection of pleural and interstitial parenchymatous abnormalities and of nodules. The technical recommendations and those for the interpretation of pleural and parenchymatous abnormalities need to be well known. They are presented in the form of an atlas that gives detailed criteria for asbestosis, pleural plaques and pleural fibrosis. The diagnosis of pleural plaques depends on the combination of clear limits at the pleural and pulmonary interface, typical topography and multiple, bilateral localization. In the context of asbestos exposure the plaques are characteristic of this exposure, unlike diffuse pleural thickening, crow's feet images, parenchymatous bands and entrapped atalectasis. The writing of the radiological report would be most appropriate on this basis.

[Compensation of malignant mesothelioma as an occupational disease in Lower Normandy, from 1995 to 2002]. / L'indemnisation du mésothéliome malin professionnel en Basse-Normandie entre 1995 et 2002.

BACKGROUND: Despite the close relation between occupational exposure to asbestos and malignant mesothelioma, the compensation of this disease is still far from being the rule. The objective of this study is to assess the compensation process of all the cases of occupational mesothelioma recorded by the regional mesothelioma registry between September 1995 and August 2002, and to make suggestions for improvement of the compensation of future cases. METHODS: Lifetime exposure to asbestos was assessed for each of the 141 mesothelioma cases observed in Lower Normandy during this time period, and 105 cases could be related to a possible, probable, or very probable occupational exposure to this mineral. Data about notification and compensation of these occupational diseases were gathered with the help of all health insurance organisms concerned. RESULTS: Except for five cases in which insurance conditions did not allow any compensation, compensation of occupational mesothelioma occurred in 85% of the cases. This high rate was probably the result of the existence of an early asbestos industry in this region, and of the particular awareness of the Norman population about asbestos-related diseases, as well as of the epidemiological follow-up of mesothelioma in Lower Normandy. When notified for compensation, all cases but one were actually compensated, and the lag-time between notification and compensation proved to decrease since 1995, with an average delay reaching 91,1 days in 2002. Patients who did not report their disease were older than those who did, and the lack of knowledge of medical practitioners about compensation procedures seems to be an important matter in this issue. CONCLUSION: In order to improve the rate of compensation of occupational malignant mesothelioma cases, information about the usual occupational origin of the disease should be delivered systematically to the general practitioner of each patient. This could be done by pathologists, when they diagnose malignant mesothelioma, and/or by medical examiners when sickness benefits are sought, or even by the epidemiological center of death causes (INSERM, CépiDc), for the beneficiaries of patients who died from malignant mesothelioma.

[Benign asbestos-related pleuropulmonary diseases]. / Affections pleuropulmonaires bénignes liées à l'amiante.

Among the non malignant diseases related to asbestos exposure, pleural plaques are the most frequent. Pleural effusion and diffuse pleural thickening, as well as asbestosis, are uncommon nowadays in asbestos-exposed screened populations. Despite the absence of any useful treatment, accurate diagnoses of these diseases are needed for two reasons: on the one hand in order to save patients from anxiety related to diagnostic and prognostic discrepancies, and on the other hand in order to ensure a proper attribution of the high social and financial compensations which are provided in France for asbestos affected patients. CT scan of the thorax is the most sensitive and specific tool for a precise diagnosis of these lesions, but it often displays minute abnormalities which may give rise to major diagnostic discordances, owing to the absence of any tomodensitometric reference in populations proved to be free from any asbestos exposure. There is a need to seek for a suitable standardization of imaging technique and interpretation, for a consensus in the characterization of CTscan abnormalities that warrant compensation, and for a careful medico-psychologic assistance for patients affected by asbestos-related benign diseases.

Incidence of digestive cancers and occupational exposure to asbestos.

While the role of exposure to asbestos in the development of several cancers such as mesotheliomas and bronchopulmonary cancers is now well established, the possible relationship between digestive cancers, other than peritoneal mesotheliomas, and occupational exposure to asbestos is still controversial. The great majority of the studies are based on mortality data. The aim of the study was to analyse the relationship between digestive cancer incidence and occupational exposure to asbestos in a population of subjects for whom precise occupational exposure data and precise incidence data were available. The population consisted of salaried and retired workers from a company using asbestos to manufacture fireproof textiles and friction materials. There were 1454 men (79.9%) and 366 women (20.1%). A cumulative exposure index and a mean exposure concentration in fibres/ml for each subject were calculated with the aid of an in-house job-exposure matrix. The number of cases of digestive cancer observed was compared with the expected and Standardized Incidence Ratio (SIR) was estimated. Precise occupational exposure data allowed us to study the dose-response relationship between asbestos exposure and risk of digestive cancer using Cox model. Fifty-six digestive cancers occurred in the study population over the 18-year follow-up period for 48.4 expected (SIR = 1.16 [0.87-1.50]). Comparing with incidence in the county, SIR was not significant for any of the digestive localization, but for peritoneum. However, even after taking into account the potential confounders via the Cox model, there was a significant dose-response relationship between the occurrence of digestive cancers and the mean exposure concentration, even after exclusion of peritoneum cancers. Our study provides initial evidence suggesting a relationship between occupational exposure to asbestos and the risk of digestive cancer: first, it is a study of incidence although the risk evidenced is not significant; secondly, a dose-effect relationship is demonstrated in the whole population. However, these preliminary results require confirmation by more powerful studies focusing on larger series.

Asbestos bodies in the sputum of asbestos workers: correlation with occupational exposure.

A cross-sectional medical survey including collection of three consecutive sputum samples was carried out among 270 retired workers of a textile and friction materials factory, in order to investigate the relationship between asbestos body identification and asbestos exposure. The individual cumulative asbestos exposure, determined by means of a plant-specific job-exposure matrix based on asbestos air measurements in the workshops, proved to be heavy with a mean cumulative exposure of 217 fibres x mL(-1) x yr. Macrophages and asbestos bodies were identified in sputum samples by light microscopy. The lung origin of the sputum, suggested by the presence of macrophages and/or asbestos bodies, was confirmed in 82.6% of subjects, and 53% of these samples were positive for asbestos bodies. The prevalence of asbestos bodies was not related to sex, smoking status or latency. Conversely, multivariate analysis showed a positive relationship with cumulative exposure, duration and intensity of exposure to asbestos, as well as age and time since retirement. These findings suggest that sputum analysis for asbestos bodies may remain a relevant and noninvasive marker of heavy occupational exposure to asbestos, even years after retirement. Owing to the new perspectives in lung cancer screening, it might contribute to the identification of high-risk subjects.

[Malignant mesothelioma in Basse-Normandie, a French population study. Descriptive analysis, prognostic factors and survival]. / Mésothéliomes malins en Basse-Normandie: analyse descriptive, facteurs pronostiques et survie. Une étude de population.

BACKGROUND: Malignant mesothelioma is a pleural and/or peritoneal tumor closely related to asbestos exposure, and its incidence should continue to increase during the first two decades of the 21(rst)century. The main prognostic factors described for this tumor are older age, sex, tumor stage and histological type. The aim of this study was to assess the incidence of pleural and peritoneal malignant mesothelioma in the County of Basse-Normandie (France), as well as their epidemiological characteristics, and the prognostic factors related to survival duration. METHODS: Cases were identified through repeated inquiries among all chest physicians and pathologists of the County of Basse-Normandie. A special care was taken in the validation of the diagnosis of each case. Incidence of mesothelioma was determined according to sex and age (5 years categories). Qualitative and quantitative variables were compared with the use of chi-square or Student's t tests respectively. Survival rate was calculated by Kaplan-Meier method, and prognostic factors were studied by means of Cox model. RESULTS: Study population consisted in all 80 malignant mesothelioma cases diagnosed in Basse-Normandie between the 1(rst) of September 1995 and the 31(rst) of August 1999. Annual incidence rates of pleural mesothelioma were 1.1/100 000 in men and 0.23/100 000 in women; annual incidence rates for peritoneal mesothelioma were 0.21/100 000 in men and 0.13/100 000 in women. Asbestos exposure was present in 63 cases (78.8%). The study of geographic distribution of mesothelioma cases revealed the influence of the main asbestos industrial settings, as well as the numerous scattered cases related to other occupational exposure. Mean survival duration was 9 months for pleural mesothelioma and 5 months for peritoneal mesothelioma. After adjustment on age, death risk was higher in asbestos-exposed than in non asbestos-exposed cases. CONCLUSION: This study confirms that malignant mesothelioma is closely related to asbestos exposure, but not only in main asbestos industrial settings. It suggests that asbestos exposure may take place among prognostic factors of this tumor.

[Nonmalignant asbestos-related diseases]. / Les pathologies asbestosiques non tumorales.

Non malignant asbestos diseases are dominated numerically by pleural plaques. This form of circumscribed fibrosis of the parietal pleural is generally asymptomatic and its potential for evolution is weak. More rarely diffuse pleural fibrosis results from disease of the visceral pleura with a secondary fusion of the two pleural layers. Usually it follows a pleural effusion which resolves spontaneously. Its functional effects are sometimes important. The generalised practice of computerized tomographic scanning as a work up for asbestos related disease has revealed the frequent association of this diffuse pleural fibrosis with a particular form of peripheral pulmonary collapse called round atelectasis. Asbestosis or pulmonary fibrosis induced by the inhalation of asbestos has become rarer due to the improvement in working conditions in the asbestos industry. It develops following heavy exposure. The frequency of bronchopulmonary cancer is increased when asbestosis exists although it is not currently possible to say if the two disorders are independent and each is only conditioned by exposure to asbestos or if the two diseases are inextricably linked by the same physiopathological process.