Osteopontin,asbestos exposure and pleural plaques: a cross-sectional study

Background  

Osteopontin (OPN) is a plasma protein/cytokine produced in excess in several malignancies. In a recent study OPN was reported as being related to the duration of asbestos exposure and presence of benign asbestos-related diseases; however, it was unclear whether this protein was an indicator of exposure or effect.     

An operated case of lung cancer with pleural plaques: its asbestos bodies, fiber analysis and asbestos exposure

This case was a 79-year-old man with pleural plaques, which had been pointed out in the left lung field on chest X-ray six years ago. A new shadow in the right chest appeared in 1999 and was closely examined. Cytological class IV carcinoma was detected in his lung tissue obtained by broncho-fiberscope. Lobectomy of the right upper lobe was performed, and calcified pleural plaques were found on the chest wall. The clinical diagnosis was poorly differentiated squamous cell carcinoma, T1N0M0. In World War II when he was 26 years old, he had worked as a boiler man on a battle cruiser for one year. The amount of asbestos bodies (AB) was 3,348 per gram dry lung tissue. The cores of AB and asbestos fibers were examined and showed that amosite was the most prevalent and crocidolite, tremolite and chrysotile were present in that order. After leaving the navy, he had worked as a farmer throughout his life, suggesting that he had never contacted asbestos occupationally after being a boiler man. It is strongly suggested that he had been exposed to asbestos during his work as a boiler man and that produced pleural plaques and lung cancer 50 years' later.     

Diachronic study of pleural plaques in rural population with environmental exposure to asbestos

BACKGROUND: The progress of pleural plaques in persons exposed to environmental asbestos in Almopia, Greece were studied prospectively. METHODS: During a 15-year period, 198 individuals, in whom pleural plaques had been observed during the period 1988-1990 were followed. Respiratory function was initially evaluated in 23. All were inhabitants of seven villages of Northern Greece, where rocks with high concentration in asbestos fibers were used for whitewashing until 1935. RESULTS: Out of this population, 126 survived and underwent chest X-ray in 2003 while respiratory function was retested in 18. New radiological findings were compared to previous ones using digital technology. Furthermore, the cause of death of the remaining 72 was recorded. Deterioration of X-ray findings was observed in all survivors. Not only did the surface area of previous plaques increase (8.66 +/- 12.6 cm2, mean value +/- SD) but new ones also appeared. Total lung capacity decreased from 95.6 +/- 14.8 in 1998 to 76.5 +/- 9.3% predicted in 2003. It was found that out of 72 deaths, 11 people died of malignant lung neoplasm, and 4 of mesothelioma. CONCLUSIONS: Radiological appearance of pleural plaques and respiratory function of people previously exposed to asbestos environmental pollution worsens over the years. Prevalence of mesothelioma was found to be higher than expected.     

Malignant pleural mesothelioma in parts of Japan in relationship to asbestos exposure

Malignant pleural mesothelioma is induced by asbestos exposure. Many reports have described this situation in America and European countries, but a few have been published in Japan. In this study malignant pleural mesothelioma cases in hospitals located in an area facing the Seto Inland Sea were evaluated. A total of 106 patients were examined with 100 patients having had occupational exposure to asbestos and 6 patients without such histories of asbestos exposure. Ninety seven were male and 9 were female. Ages ranged from 41 to 87 yr with mean of 64.8+/-5.3 yr. Thirty seven cases showed epithelial type of tumor, 25 biphasic type and 15 showed sarcomatous. The remaining 23 cases had insufficient evidence for typing the tumor. The mean survival rate for all cases was 9.2+/-11.6 months. Fifty-one patients had occupational histories of shipyard work, 16 patients worked in asbestos cement piping, and the remainder were employed in miscellaneous jobs related asbestos exposure. The duration of asbestos exposure ranged up to 20 yr or longer with the mean of 17.2+/-8.9 yr and the average latent period for the occurrence of malignant pleural mesothelioma was more than 31 yr with the mean of 37.0+/-13.3 yr. Quantification of asbestos bodies in the lungs indicated a high concentration in most patients and the major types of asbestos fibers were crocidolite and amosite. Six cases appeared after exposure to chrysotile. These results indicated that ninety four percent of malignant pleural mesothelioma appeared due to the exposure to asbestos including crocidolite and amosite. The remainder may be blamed on exposure to chrysotile.     

The prevalence of pleural plaques and/or pulmonary changes among construction workers in Okayama, Japan

BACKGROUND: Since asbestos has been widely used in Japanese building materials since 1960s, a large number of Japanese construction workers may be exposed to asbestos occupationally. METHODS: Among 2951 construction workers in Okayama, Japan, the prevalence of asbestos-induced pleural or pulmonary changes was examined by screening chest x-rays; these findings were confirmed by computed tomography (CT) scanning of the chest. RESULTS: Among 2951 construction workers, 168 (5.7%) were found to have significant findings for pleural plaque or pulmonary changes on chest x-ray. Seventy-four had both pleural plaque and asbestosis, 85 pleural plaques alone, and 9 asbestosis alone. In 11 subjects, pleural plaques were suggested by chest x-ray, but neither pleural plaque nor asbestosis was demonstrated by chest CT. Honeycombing as one of the characteristic findings of asbestosis was found in 29 subjects. Others showed subpleural spots or curvilinear shadow, which suggested the early stage of asbestosis. The occupations of these workers were carpenters (64), plasterers (27), and concrete board cutters (14). About 30% of the workers with these findings were aware that they were handling asbestos in activities such as installation of asbestos boards, and/or asbestos spraying. CONCLUSIONS: As the incidence of malignant mesothelioma and primary lung cancer associated with asbestos exposure are high, screening by chest CT is necessary for detecting asbestos-induced pulmonary and/or pleural lesions. Education for protection such as telling about the presence of asbestos in building materials is also necessary.     

Relationship between pleural plaques prevalence and extension and biomarkers of cumulative asbestos dose. A necropsy study

Background:The relationship between pleural plaques and cumulative asbestos exposure is controversial.Objectives:To evaluate the relationship between lung asbestos bodies (AB) and fibres (AF) and plaques presence and extension.Methods:In a necropsy series of shipyard workers with asbestos-related diseases, we measured counts (per g of dry lung tissue) of AB (thousands) and AF>1 μm (millions). Pleural plaques were classified into three extension grades. We fitted univariate and multivariable linear (dependent variables: AB and AF, log₁₀ transformed) and multinomial (dependent variable: plaques grade) regression models.Results:We analysed 124 subjects, 13 without plaques 20 with grade 1, 69 with grade 2, and 22 with grade 3 plaques. Geometric means (GM) of AB were 10.6, 23.3, 126, and 140 in the four groups respectively (P=0.0001). GMs for AF (mostly amphiboles) were 1.2, 1.4, 7.3, and 12.9 (P=0.0001). AB and AF were strongly correlated (r=0.81). The likelihood of no plaques and grade 1 plaques decreased with increasing AB and AF doses, with a corresponding increase of grade 2 and 3 plaques. Plaque presence and extension was also associated with histologically verified asbestosis (P<0.001).Conclusions:Our study showed a strong positive relationship between pleural plaque presence and extension and both lung asbestos burden and asbestosis.Key words: Pleural plaques, lung asbestos fibre burden     

Incidence of pleural mesothelioma in New Caledonia: a 10-year survey (1978-1987)

All cases of primary pleural cancers that were reported during a 10-y period (i.e., 1978-1987) in New Caledonia were recorded and compared with five cancer registers. There was an excess of primary pleural cancers in the area of New Caledonia, and it was particularly evident among the Melanesian ethnic group. Neither geographical nor occupational factors accounted for these results, but an environmental factor could not be excluded.     

Malignant pleural cancers mortality and compensated cases for asbestos related diseases in Lazio municipalities (1980-2001)

BACKGROUND: Occupational exposure to asbestos has been widely reported in the Region, but a high risk for non-occupational and environmental contaminations have also been documented. OBJECTIVES: To describe the geographical distribution ofpleural cancer deaths and compensated asbestosis cases from 1980 to 2001 in the Lazio Region. METHODS: For each municipality Standardized Mortality Ratios (SMRs) for pleural cancer and Standardized Incidence Ratios (SIRs) for asbestosis were estimated. Expected cases were estimated from age and gender specific rates in Lazio. SatScan software was used to identify clusters and to verf;j their statistical significance. RESULTS: 789 deaths from pleural cancer (495 males and 294 females) occurred in Lazio from 1980 to 2001. The standardized mortality rate per 100.000 inhabitants is 0,74 (0,95 for males and 0,54 for females). The main excess mortality from pleural cancer occurred in the municipalities of Civitavecchia (SMR: 269,9; 95% CI: 164,9 - 416,8), Colleferro (SMR: 304,9; 95% CI: 139,4-578,8) and Rocca Priora (SMR: 379,2; 95% CI: 103,3-970,9). Significant SIRs for compensated asbestosis cases were found in the industrial areas of the Naples-Rome highway and in the shipyard area of Civitavecchia. Nofemale compensated cases were found. The most important clusters were identified in the municipality of Civitavecchia for pleural cancer (p-value = 0,117) and in the Colleferro industrial area for compensated asbestosis cases (p-value = 0,001). CONCLUSIONS: Epidemiological surveillance of incident cases of malignant mesothelioma in the Lazio Region and the investigation of modalities of asbestos exposure are urgently needed for prevention of occupational diseases.     

Course and distribution of mortality of pleural mesothelioma in The Netherlands, 1970-1987

In this article the sex- and age-specific trends and geographical distribution of asbestos related pleural mesothelioma mortality in the Netherlands between 1970 and 1987 are investigated. For men total mortality increased from 10.8 per million during 1970-1978 to 20.9 per million during 1979-1987. The highest mortality occurred with 147.7 per million in 1987 in the age group between 65 and 74 years. Mortality rates for the age group between 55 and 64 years amounted to 96.5 per million in 1987. The geographical distribution over the country showed a strong concentration of male mesothelioma cases in the regions with many harbours, shipyards and heavy industries round Amsterdam, IJmuiden, Rotterdam, Dordrecht and Walcheren. Using linear regression techniques, it was calculated that several thousands new mesothelioma cases will occur in the Netherlands during the next two decades. A significant decrease in mesothelioma mortality can not be expected before 2010.     

Asbestos exposure,pleural plaques and the risk of lung cancer

Summary Studies which have evaluated the relationship between pleural plaques and smoking have found a higher prevalence of smokers among persons with pleural plaques. Pleural plaques are a relatively frequent finding among persons with occupational exposure to asbestos. Some studies, but not others, have shown that persons with pleural plaques have a higher risk of lung cancer. None of these studies controlled for the effects of smoking, and since smoking is more prevalent among persons with pleural plaques, it is unlikely that the increased risk of lung cancer to persons with pleural plaques, found in some studies, is due to the pleural plaques.     

HIV infection in Ukraine (1987-96)

In Ukraine, the number of reported HIV infections increased extremely rapidly during the second half of the 1990s, from less than 50 per year until 1994 to more than 12,000 in 1996. The increase was initially observed and was particularly striking in the regions along the Black Sea. The majority of reported HIV infections were diagnosed in injecting drug users. The extend of HIV spread through sexual transmission is more difficult to assess because of the strong social stigma attached to homosexuality and the lack of information on sexual behaviour in general. The reported number of syphilis cases have also dramatically increased, from 3,000 cases in 1990 to nearly 80,000 cases in 1996. In this paper, we describe the surveillance systems for, and epidemiologic data on HIV infections, AIDS, and other STD in Ukraine from 1987 to 1996. We review the contributions of different vulnerable groups and we also discuss the factors influencing the past spread and the potential for future spread of HIV infection and make recommendations for surveillance, research and prevention.     

Dynamics of the lung function in asbestos pleural disease

As a rule, asbestosis is a disease of workers who are occupationally exposed to inhalation of asbestos dust, leaving permanent alterations on the lung parenchyma or pleura. In our ten-year study, we investigated 318 workers with pleural asbestosis from whom we took medical history which included occupational exposure to asbestos, radiological examinations and lung function, which is mandatory for the diagnosis and the follow up of the disease. We analysed functional parameters such as forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1) and intermediate forced expiratory flow at 25% to 75% (FEF25%-75%). In addition, we investigated the predicted values of functional parameters according to smoking and non-smoking habits. We found a significant reduction in vital capacity, particularly in smokers after 25 years of exposure to asbestos. During the first 15 years, values of vital capacity on the group basis remained inside the 80% of the normal values and were not significant for assessing the dynamics of the lung function. To better assess the effects of occupational asbestos exposure, it is necessary to interpret lung function data not only on the group basis, but also for each subject individually.